Pediatric Dermatology Consult

KOH analysis of the scales from the scalp areas revealed no fungal elements. Given the observed erythema and scaling, a punch biopsy was conducted. Histopathological examination of the biopsy sample displayed interface inflammation affecting both the infundibular and lower portions of hair follicles. The presence of folliculosebaceous units transitioning from intermediate to terminal size follicles was noted. A perifollicular, peri eccrine, superficial, and deep perivascular lymphoplasmacytic infiltrate was identified, alongside increased dermal mucin, findings consistent with a diagnosis of discoid lupus erythematosus.

Subsequent laboratory investigations were largely unremarkable, except for an elevated ANA titer (1:320, with a speckled pattern). The patient was initiated on a treatment regimen comprising intralesional triamcinolone and oral hydroxychloroquine (Plaquenil).

167686_scalp1_web.jpg

Discussion

Pediatric discoid lupus erythematosus (DLE) is a rare but chronic autoimmune condition, representing one of the most prevalent forms of cutaneous lupus erythematosus. It predominantly affects adults, yet pediatric cases account for 5%-7% of DLE diagnoses, with a significant predominance in females. Pediatric scalp DLE is particularly concerning due to its potential for causing scarring and permanent hair loss, which can significantly impact the psychological wellbeing of affected children.

The pathogenesis of DLE is multifactorial, involving genetic predispositions, environmental factors like UV light exposure, and immunological mechanisms leading to skin damage.

In children, DLE typically presents as well-demarcated, erythematous plaques with scale and follicular plugging, primarily affecting the scalp. Lesions may also exhibit changes in pigmentation, atrophy, and telangiectasia. The scalp involvement often leads to scarring alopecia, which can be distressing for pediatric patients. Unlike systemic lupus erythematosus (SLE), DLE is usually limited to the skin without systemic involvement. The progression of DLE to systemic lupus erythematosus in children has been previously described to be 22.2%. In a recent report of 201 pediatric cases of DLE, 12% of the cases progressed to systemic lupus erythematosus (SLE) and 14.5% had concurrent SLE. The onset of symptoms before the age of 10 years was the only statistically significant predictor for progression to SLE. Pruritus is a common symptom and may be correlated with disease activity.

The differential diagnosis for this patient encompassed a variety of conditions, including tinea capitis, alopecia areata, trichotillomania, and lichen planopilaris, each considered based on clinical presentation but ultimately excluded through clinical, microscopic, and biopsy findings.

Matiz_Catalina_SanDiego.jpg

Conclusion

The prognosis for pediatric scalp DLE can be favorable with timely and appropriate management, underscoring the importance of early diagnosis and intervention to prevent scarring and hair loss. However, ongoing surveillance is crucial for monitoring potential progression to systemic lupus erythematosus, albeit a low-risk transformation.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

1. George PM and Tunnessen WW. Childhood discoid lupus erythematosus. Arch Dermatol. 1993;129(5):613-617.

2. Hawat T et al. Pediatric discoid lupus erythematosus: Short report. Dermatol Ther. 2022 Jan;35(1):e15170. doi: 10.1111/dth.15170.

3. Arkin LM et al. Practice-based differences in paediatric discoid lupus erythematosus. Br J Dermatol. 2019 Oct;181(4):805-810. doi: 10.1111/bjd.17780.

KOH analysis of the scales from the scalp areas revealed no fungal elements. Given the observed erythema and scaling, a punch biopsy was conducted. Histopathological examination of the biopsy sample displayed interface inflammation affecting both the infundibular and lower portions of hair follicles. The presence of folliculosebaceous units transitioning from intermediate to terminal size follicles was noted. A perifollicular, peri eccrine, superficial, and deep perivascular lymphoplasmacytic infiltrate was identified, alongside increased dermal mucin, findings consistent with a diagnosis of discoid lupus erythematosus.

Subsequent laboratory investigations were largely unremarkable, except for an elevated ANA titer (1:320, with a speckled pattern). The patient was initiated on a treatment regimen comprising intralesional triamcinolone and oral hydroxychloroquine (Plaquenil).

167686_scalp1_web.jpg

Discussion

Pediatric discoid lupus erythematosus (DLE) is a rare but chronic autoimmune condition, representing one of the most prevalent forms of cutaneous lupus erythematosus. It predominantly affects adults, yet pediatric cases account for 5%-7% of DLE diagnoses, with a significant predominance in females. Pediatric scalp DLE is particularly concerning due to its potential for causing scarring and permanent hair loss, which can significantly impact the psychological wellbeing of affected children.

The pathogenesis of DLE is multifactorial, involving genetic predispositions, environmental factors like UV light exposure, and immunological mechanisms leading to skin damage.

In children, DLE typically presents as well-demarcated, erythematous plaques with scale and follicular plugging, primarily affecting the scalp. Lesions may also exhibit changes in pigmentation, atrophy, and telangiectasia. The scalp involvement often leads to scarring alopecia, which can be distressing for pediatric patients. Unlike systemic lupus erythematosus (SLE), DLE is usually limited to the skin without systemic involvement. The progression of DLE to systemic lupus erythematosus in children has been previously described to be 22.2%. In a recent report of 201 pediatric cases of DLE, 12% of the cases progressed to systemic lupus erythematosus (SLE) and 14.5% had concurrent SLE. The onset of symptoms before the age of 10 years was the only statistically significant predictor for progression to SLE. Pruritus is a common symptom and may be correlated with disease activity.

The differential diagnosis for this patient encompassed a variety of conditions, including tinea capitis, alopecia areata, trichotillomania, and lichen planopilaris, each considered based on clinical presentation but ultimately excluded through clinical, microscopic, and biopsy findings.

Matiz_Catalina_SanDiego.jpg

Conclusion

The prognosis for pediatric scalp DLE can be favorable with timely and appropriate management, underscoring the importance of early diagnosis and intervention to prevent scarring and hair loss. However, ongoing surveillance is crucial for monitoring potential progression to systemic lupus erythematosus, albeit a low-risk transformation.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

1. George PM and Tunnessen WW. Childhood discoid lupus erythematosus. Arch Dermatol. 1993;129(5):613-617.

2. Hawat T et al. Pediatric discoid lupus erythematosus: Short report. Dermatol Ther. 2022 Jan;35(1):e15170. doi: 10.1111/dth.15170.

3. Arkin LM et al. Practice-based differences in paediatric discoid lupus erythematosus. Br J Dermatol. 2019 Oct;181(4):805-810. doi: 10.1111/bjd.17780.

KOH analysis of the scales from the scalp areas revealed no fungal elements. Given the observed erythema and scaling, a punch biopsy was conducted. Histopathological examination of the biopsy sample displayed interface inflammation affecting both the infundibular and lower portions of hair follicles. The presence of folliculosebaceous units transitioning from intermediate to terminal size follicles was noted. A perifollicular, peri eccrine, superficial, and deep perivascular lymphoplasmacytic infiltrate was identified, alongside increased dermal mucin, findings consistent with a diagnosis of discoid lupus erythematosus.

Subsequent laboratory investigations were largely unremarkable, except for an elevated ANA titer (1:320, with a speckled pattern). The patient was initiated on a treatment regimen comprising intralesional triamcinolone and oral hydroxychloroquine (Plaquenil).

167686_scalp1_web.jpg

Discussion

Pediatric discoid lupus erythematosus (DLE) is a rare but chronic autoimmune condition, representing one of the most prevalent forms of cutaneous lupus erythematosus. It predominantly affects adults, yet pediatric cases account for 5%-7% of DLE diagnoses, with a significant predominance in females. Pediatric scalp DLE is particularly concerning due to its potential for causing scarring and permanent hair loss, which can significantly impact the psychological wellbeing of affected children.

The pathogenesis of DLE is multifactorial, involving genetic predispositions, environmental factors like UV light exposure, and immunological mechanisms leading to skin damage.

In children, DLE typically presents as well-demarcated, erythematous plaques with scale and follicular plugging, primarily affecting the scalp. Lesions may also exhibit changes in pigmentation, atrophy, and telangiectasia. The scalp involvement often leads to scarring alopecia, which can be distressing for pediatric patients. Unlike systemic lupus erythematosus (SLE), DLE is usually limited to the skin without systemic involvement. The progression of DLE to systemic lupus erythematosus in children has been previously described to be 22.2%. In a recent report of 201 pediatric cases of DLE, 12% of the cases progressed to systemic lupus erythematosus (SLE) and 14.5% had concurrent SLE. The onset of symptoms before the age of 10 years was the only statistically significant predictor for progression to SLE. Pruritus is a common symptom and may be correlated with disease activity.

The differential diagnosis for this patient encompassed a variety of conditions, including tinea capitis, alopecia areata, trichotillomania, and lichen planopilaris, each considered based on clinical presentation but ultimately excluded through clinical, microscopic, and biopsy findings.

Matiz_Catalina_SanDiego.jpg

Conclusion

The prognosis for pediatric scalp DLE can be favorable with timely and appropriate management, underscoring the importance of early diagnosis and intervention to prevent scarring and hair loss. However, ongoing surveillance is crucial for monitoring potential progression to systemic lupus erythematosus, albeit a low-risk transformation.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

1. George PM and Tunnessen WW. Childhood discoid lupus erythematosus. Arch Dermatol. 1993;129(5):613-617.

2. Hawat T et al. Pediatric discoid lupus erythematosus: Short report. Dermatol Ther. 2022 Jan;35(1):e15170. doi: 10.1111/dth.15170.

3. Arkin LM et al. Practice-based differences in paediatric discoid lupus erythematosus. Br J Dermatol. 2019 Oct;181(4):805-810. doi: 10.1111/bjd.17780.

During examination, the patient was observed repetitively cracking his knuckles, making a fist with the right hand, placing the left hand on top, and rubbing the hand, a behavior he routinely did multiple times daily. The observed pattern of finger involvement on the dorsum of the right hand corresponded to areas subjected to significant pressure during the described activity. Consequently, a diagnosis of lichen simplex chronicus (LSC) secondary to mechanical rubbing, along with associated pachydermodactyly on the fingers of the right hand, was established.

166925_clenched_hands_web.jpg

Lichen simplex chronicus and pachydermodactyly are both attributed to microtrauma inflicted upon the skin. Lichen simplex chronicus often constitutes a diagnosis of exclusion and is characterized by repetitive trauma-induced keratinocyte proliferation and melanocyte activation, resulting in hyperpigmentation and skin thickening. Although typically observed in women between the fourth and fifth decades of life, LSC is rarely reported in children. In adults, LSC-related rubbing or scratching frequently arises from chronic pruritic dermatitis such as eczema or psoriasis, neurodermatitis from dysesthesia, or habitual movements, as exhibited by this young patient. While generally benign, LSC may become infected. In rare instances, malignant transformation may occur.

The association with pachydermodactyly implicates microtrauma, necessitating careful observation and questioning to elucidate the cause, as demonstrated in this case. Lesions are typically hyperpigmented, though cases of associated hypopigmentation or depigmentation have been documented. Affected areas typically fall within the patient’s hand and finger reach, with lesion improvement over several months achievable through trigger avoidance.
 

Pachydermodactyly, a rare but benign fibromatosis around the proximal interphalangeal joints, is often misdiagnosed as juvenile idiopathic arthritis, potentially leading to unnecessary treatments and patient anxiety. Microtrauma history due to digit manipulation is prevalent among affected individuals, with most also exhibiting neuropsychiatric disorders. Histological examination of pachydermodactyly reveals hypergranulosis and dermal thickening, accompanied by increased fibroblasts and collagen types I, III, and V, differing from the epidermal changes seen in LSC.

The differential diagnosis also included phytophotodermatitis, a phototoxic dermatologic reaction following exposure to ultraviolet light subsequent to contact with furocoumarin-containing plant chemicals. However, the persistence of the patient’s lesions for over a year precluded this diagnosis. Secondary hyperpigmentation was also contemplated but excluded due to the absence of preceding inflammatory dermatitis.

Matiz_Catalina_SanDiego.jpg

Treatment of LSC primarily involves identifying and addressing any underlying conditions, repairing the skin barrier, reducing inflammation, and modifying behaviors contributing to chronic microtrauma, as observed in this patient. Topical corticosteroids may aid in decreasing epidermal thickening and discoloration, though lesion resolution necessitates behavior cessation.

It’s important to identify these types of skin changes in children to avoid unnecessary medical treatments for these benign conditions.
 

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested Reading

Seier JA, Dissemond J. Lichen Simplex Chronicus Due to Mechanical Irritation. Dtsch Arztebl Int. 2022 Nov 18;119(46):802. doi: 10.3238/arztebl.m2022.0213.

Small S et al. A 12-Year-Old Boy Presenting With Unilateral Proximal Interphalangeal Joint Swelling. BMJ Case Rep. 2011 Apr 13:2011:bcr0120113719. doi: 10.1136/bcr.01.2011.3719.

Voicu C et al Lichen Simplex Chronicus as an Essential Part of the Dermatologic Masquerade. Open Access Maced J Med Sci. 2017 Jul 24;5(4):556-557. doi: 10.3889/oamjms.2017.133.

During examination, the patient was observed repetitively cracking his knuckles, making a fist with the right hand, placing the left hand on top, and rubbing the hand, a behavior he routinely did multiple times daily. The observed pattern of finger involvement on the dorsum of the right hand corresponded to areas subjected to significant pressure during the described activity. Consequently, a diagnosis of lichen simplex chronicus (LSC) secondary to mechanical rubbing, along with associated pachydermodactyly on the fingers of the right hand, was established.

166925_clenched_hands_web.jpg

Lichen simplex chronicus and pachydermodactyly are both attributed to microtrauma inflicted upon the skin. Lichen simplex chronicus often constitutes a diagnosis of exclusion and is characterized by repetitive trauma-induced keratinocyte proliferation and melanocyte activation, resulting in hyperpigmentation and skin thickening. Although typically observed in women between the fourth and fifth decades of life, LSC is rarely reported in children. In adults, LSC-related rubbing or scratching frequently arises from chronic pruritic dermatitis such as eczema or psoriasis, neurodermatitis from dysesthesia, or habitual movements, as exhibited by this young patient. While generally benign, LSC may become infected. In rare instances, malignant transformation may occur.

The association with pachydermodactyly implicates microtrauma, necessitating careful observation and questioning to elucidate the cause, as demonstrated in this case. Lesions are typically hyperpigmented, though cases of associated hypopigmentation or depigmentation have been documented. Affected areas typically fall within the patient’s hand and finger reach, with lesion improvement over several months achievable through trigger avoidance.
 

Pachydermodactyly, a rare but benign fibromatosis around the proximal interphalangeal joints, is often misdiagnosed as juvenile idiopathic arthritis, potentially leading to unnecessary treatments and patient anxiety. Microtrauma history due to digit manipulation is prevalent among affected individuals, with most also exhibiting neuropsychiatric disorders. Histological examination of pachydermodactyly reveals hypergranulosis and dermal thickening, accompanied by increased fibroblasts and collagen types I, III, and V, differing from the epidermal changes seen in LSC.

The differential diagnosis also included phytophotodermatitis, a phototoxic dermatologic reaction following exposure to ultraviolet light subsequent to contact with furocoumarin-containing plant chemicals. However, the persistence of the patient’s lesions for over a year precluded this diagnosis. Secondary hyperpigmentation was also contemplated but excluded due to the absence of preceding inflammatory dermatitis.

Matiz_Catalina_SanDiego.jpg

Treatment of LSC primarily involves identifying and addressing any underlying conditions, repairing the skin barrier, reducing inflammation, and modifying behaviors contributing to chronic microtrauma, as observed in this patient. Topical corticosteroids may aid in decreasing epidermal thickening and discoloration, though lesion resolution necessitates behavior cessation.

It’s important to identify these types of skin changes in children to avoid unnecessary medical treatments for these benign conditions.
 

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested Reading

Seier JA, Dissemond J. Lichen Simplex Chronicus Due to Mechanical Irritation. Dtsch Arztebl Int. 2022 Nov 18;119(46):802. doi: 10.3238/arztebl.m2022.0213.

Small S et al. A 12-Year-Old Boy Presenting With Unilateral Proximal Interphalangeal Joint Swelling. BMJ Case Rep. 2011 Apr 13:2011:bcr0120113719. doi: 10.1136/bcr.01.2011.3719.

Voicu C et al Lichen Simplex Chronicus as an Essential Part of the Dermatologic Masquerade. Open Access Maced J Med Sci. 2017 Jul 24;5(4):556-557. doi: 10.3889/oamjms.2017.133.

During examination, the patient was observed repetitively cracking his knuckles, making a fist with the right hand, placing the left hand on top, and rubbing the hand, a behavior he routinely did multiple times daily. The observed pattern of finger involvement on the dorsum of the right hand corresponded to areas subjected to significant pressure during the described activity. Consequently, a diagnosis of lichen simplex chronicus (LSC) secondary to mechanical rubbing, along with associated pachydermodactyly on the fingers of the right hand, was established.

166925_clenched_hands_web.jpg

Lichen simplex chronicus and pachydermodactyly are both attributed to microtrauma inflicted upon the skin. Lichen simplex chronicus often constitutes a diagnosis of exclusion and is characterized by repetitive trauma-induced keratinocyte proliferation and melanocyte activation, resulting in hyperpigmentation and skin thickening. Although typically observed in women between the fourth and fifth decades of life, LSC is rarely reported in children. In adults, LSC-related rubbing or scratching frequently arises from chronic pruritic dermatitis such as eczema or psoriasis, neurodermatitis from dysesthesia, or habitual movements, as exhibited by this young patient. While generally benign, LSC may become infected. In rare instances, malignant transformation may occur.

The association with pachydermodactyly implicates microtrauma, necessitating careful observation and questioning to elucidate the cause, as demonstrated in this case. Lesions are typically hyperpigmented, though cases of associated hypopigmentation or depigmentation have been documented. Affected areas typically fall within the patient’s hand and finger reach, with lesion improvement over several months achievable through trigger avoidance.
 

Pachydermodactyly, a rare but benign fibromatosis around the proximal interphalangeal joints, is often misdiagnosed as juvenile idiopathic arthritis, potentially leading to unnecessary treatments and patient anxiety. Microtrauma history due to digit manipulation is prevalent among affected individuals, with most also exhibiting neuropsychiatric disorders. Histological examination of pachydermodactyly reveals hypergranulosis and dermal thickening, accompanied by increased fibroblasts and collagen types I, III, and V, differing from the epidermal changes seen in LSC.

The differential diagnosis also included phytophotodermatitis, a phototoxic dermatologic reaction following exposure to ultraviolet light subsequent to contact with furocoumarin-containing plant chemicals. However, the persistence of the patient’s lesions for over a year precluded this diagnosis. Secondary hyperpigmentation was also contemplated but excluded due to the absence of preceding inflammatory dermatitis.

Matiz_Catalina_SanDiego.jpg

Treatment of LSC primarily involves identifying and addressing any underlying conditions, repairing the skin barrier, reducing inflammation, and modifying behaviors contributing to chronic microtrauma, as observed in this patient. Topical corticosteroids may aid in decreasing epidermal thickening and discoloration, though lesion resolution necessitates behavior cessation.

It’s important to identify these types of skin changes in children to avoid unnecessary medical treatments for these benign conditions.
 

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested Reading

Seier JA, Dissemond J. Lichen Simplex Chronicus Due to Mechanical Irritation. Dtsch Arztebl Int. 2022 Nov 18;119(46):802. doi: 10.3238/arztebl.m2022.0213.

Small S et al. A 12-Year-Old Boy Presenting With Unilateral Proximal Interphalangeal Joint Swelling. BMJ Case Rep. 2011 Apr 13:2011:bcr0120113719. doi: 10.1136/bcr.01.2011.3719.

Voicu C et al Lichen Simplex Chronicus as an Essential Part of the Dermatologic Masquerade. Open Access Maced J Med Sci. 2017 Jul 24;5(4):556-557. doi: 10.3889/oamjms.2017.133.

Diagnosis: Infection-induced psoriasis (guttate-type, induced by streptococcal intertrigo)

Psoriasis is a chronic inflammatory disorder characterized by well-defined, scaly, erythematous plaques. Guttate psoriasis is a distinct variant of psoriasis that is more common in children and adolescents. Guttate psoriasis usually presents with multiple, scattered, small, drop-like (“guttate”), scaly, erythematous papules and plaques. Guttate psoriasis may be triggered by infections, most commonly recent streptococcal infections.

166505_baby_2_web.jpg

The pathophysiology of psoriasis involves an interplay between genetic and environmental factors. Guttate psoriasis is a chronic T-cell–mediated inflammatory disease in which there is an altered balance between T-helper-1 (TH1) and TH2 cells, transcription factor genes, and their products. HLA B-13, B-17, and Cw6 are human leukocyte antigen alleles implicated in genetic susceptibility. It is hypothesized that streptococcal infection precipitates guttate psoriasis by streptococcal superantigen–driven activation of cutaneous lymphocyte-associated antigen (CLA)–positive lymphocytes. It has been shown that streptococcal exotoxins and streptococcal M proteins act as superantigens.

Diagnosis is often made clinically based on characteristic physical findings and a possible preceding history of streptococcal infection. In patients with streptococcal infection, culture from an appropriate site and measurement of serum antistreptococcal antibody titers (for example, anti-DNase, antihyaluronidase and antistreptolysin-O) can help. A skin biopsy is usually not necessary but may be considered.

This patient presented with intertrigo of the neck and axillae at the time of presentation with the papulosquamous rash. Culture of the intertrigo yielded 4+ Group A beta streptococcus.
 

Treatment

Although there is currently no cure for guttate psoriasis, various treatment options can relieve symptoms and clear skin lesions, and infection-triggered lesions may remit, usually within several months. However, guttate psoriasis may persist and progress to chronic plaque psoriasis. Many treatment options are based mainly on clinical trials targeted for plaque psoriasis treatment.

Lee_Danny_SANDIEGO_web.jpg

For mild psoriasis, topical corticosteroids are first-line treatment. Other topical steroids include vitamin D analogs (calcipotriene), topical retinoids (tazarotene), topical calcineurin inhibitors (tacrolimus and pimecrolimus), and newer non-steroidal anti-inflammatory agents (roflumilast or tapinarof), neither approved yet in this young age group. In more severe cases, phototherapy with UVB light, traditional systemic immunosuppressive agents (methotrexate, cyclosporine) or targeted biologic therapies may be considered.
 

Differential Diagnosis

The differential diagnosis may include generalized intertrigo, pityriasis rubra pilaris, tinea corporis, atopic dermatitis, and staphylococcal scalded skin syndrome. Guttate psoriasis can be distinguished by history and physical exam. Further studies such as potassium hydroxide (KOH) scrapings may be helpful in ruling out the other disorders.

Le_Samuel_SANDIEGO_web.jpg

Intertrigo is an inflammatory condition of the flexural surfaces irritated by warm temperatures, friction, moisture, and poor ventilation that is commonly associated with Candida infection and/or streptococcal infection. Candidal intertrigo can present with erythematous patches or plaques in an intertriginous area that may develop erosions, macerations, fissures, crust, and weeping. Satellite papules and pustules are pathognomonic for Candida species. Streptococcal intertrigo usually presents with bright red color and may be painful or pruritic. Perianal streptococcal infection is reported as a trigger of guttate psoriasis in pediatric patients.

Pityriasis rubra pilaris is a rare inflammatory papulosquamous disorder with an unknown etiology. Red-orange papules and plaques, hyperkeratotic follicular papules, and palmoplantar hyperkeratosis are primary features. Diagnosis is based on clinical and histopathology. Pityriasis rubra pilaris is self-limited and asymptomatic in many cases. Treatment may not be required, but combination therapy with topical agents includes emollients, keratolytic agents (for example, urea, salicylic acid, alpha-hydroxy acids), topical corticosteroids, tazarotene, and topical calcineurin inhibitors. Systemic agents include oral retinoids and methotrexate.

Eichenfield_Lawrence_CA_web.jpg

Atopic dermatitis is a chronic inflammatory skin disease that involves genetic and environmental factors, leading to abnormalities in the epidermis and the immune system presenting with its typical morphology and distribution. The morphology of eczematous lesions is distinct from papulosquamous lesions of psoriasis.

Staphylococcal scalded skin syndrome is a toxin-mediated skin disorder which presents with denuded, peeling skin due to epidermolytic exotoxin producing Staphylococcus species. Fever, erythematous rash, malaise, skin pain, and irritability presents initially. Progressive desquamation with accentuation in folds is typical, with progression usually within 1-2 days. Systemic antibiotics covering Staphylococcus should be administered early. Emollients and nonadherent dressings should be applied to affected areas to promote healing. Supportive care includes dehydration management, temperature regulation, and nutrition. Skin desquamation usually occurs within 5 days with resolution within 2 weeks.

This infant displayed streptococcal intertrigo which triggered an early presentation of guttate psoriasis. The patient was managed with completion of a course of oral cephalexin, midstrength topical corticosteroids to the truncal lesions, and mild topical corticosteroids to the face and diaper area with good clinical response.
 

Danny Lee and Samuel Le serve as research fellows in the Pediatric Dermatology Division of the Department of Dermatology at the University of California San Diego and Rady Children’s Hospital, San Diego. Dr. Eichenfield is Distinguished Professor of Dermatology and Pediatrics and Vice-Chair of the Department of Dermatology at the University of California San Diego and Rady Children’s Hospital, San Diego. The authors have no relevant financial disclosures.

Suggested Reading

Leung AK et al. Childhood guttate psoriasis: An updated review. Drugs Context. 2023 Oct 23:12:2023-8-2. doi: 10.7573/dic.2023-8-2.

Galili E et al. New-onset guttate psoriasis: A long-term follow-up study. Dermatology. 2023;239(2):188-194. doi: 10.1159/000527737.

Duffin KC et al. Advances and controversies in our understanding of guttate and plaque psoriasis. J Rheumatol. 2023 Nov;50(Suppl 2):4-7. doi: 10.3899/jrheum.2023-0500.

Saleh D, Tanner LS. Guttate Psoriasis. [Updated 2023 Jul 31]. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; 2023 Jan-. Available from: www.ncbi.nlm.nih.gov/books/NBK482498/

Dupire G et al. Antistreptococcal interventions for guttate and chronic plaque psoriasis. Cochrane Database Syst Rev. 2019 Mar 5;3(3):CD011571. doi: 10.1002/14651858.CD011571.pub2.

Diagnosis: Infection-induced psoriasis (guttate-type, induced by streptococcal intertrigo)

Psoriasis is a chronic inflammatory disorder characterized by well-defined, scaly, erythematous plaques. Guttate psoriasis is a distinct variant of psoriasis that is more common in children and adolescents. Guttate psoriasis usually presents with multiple, scattered, small, drop-like (“guttate”), scaly, erythematous papules and plaques. Guttate psoriasis may be triggered by infections, most commonly recent streptococcal infections.

166505_baby_2_web.jpg

The pathophysiology of psoriasis involves an interplay between genetic and environmental factors. Guttate psoriasis is a chronic T-cell–mediated inflammatory disease in which there is an altered balance between T-helper-1 (TH1) and TH2 cells, transcription factor genes, and their products. HLA B-13, B-17, and Cw6 are human leukocyte antigen alleles implicated in genetic susceptibility. It is hypothesized that streptococcal infection precipitates guttate psoriasis by streptococcal superantigen–driven activation of cutaneous lymphocyte-associated antigen (CLA)–positive lymphocytes. It has been shown that streptococcal exotoxins and streptococcal M proteins act as superantigens.

Diagnosis is often made clinically based on characteristic physical findings and a possible preceding history of streptococcal infection. In patients with streptococcal infection, culture from an appropriate site and measurement of serum antistreptococcal antibody titers (for example, anti-DNase, antihyaluronidase and antistreptolysin-O) can help. A skin biopsy is usually not necessary but may be considered.

This patient presented with intertrigo of the neck and axillae at the time of presentation with the papulosquamous rash. Culture of the intertrigo yielded 4+ Group A beta streptococcus.
 

Treatment

Although there is currently no cure for guttate psoriasis, various treatment options can relieve symptoms and clear skin lesions, and infection-triggered lesions may remit, usually within several months. However, guttate psoriasis may persist and progress to chronic plaque psoriasis. Many treatment options are based mainly on clinical trials targeted for plaque psoriasis treatment.

Lee_Danny_SANDIEGO_web.jpg

For mild psoriasis, topical corticosteroids are first-line treatment. Other topical steroids include vitamin D analogs (calcipotriene), topical retinoids (tazarotene), topical calcineurin inhibitors (tacrolimus and pimecrolimus), and newer non-steroidal anti-inflammatory agents (roflumilast or tapinarof), neither approved yet in this young age group. In more severe cases, phototherapy with UVB light, traditional systemic immunosuppressive agents (methotrexate, cyclosporine) or targeted biologic therapies may be considered.
 

Differential Diagnosis

The differential diagnosis may include generalized intertrigo, pityriasis rubra pilaris, tinea corporis, atopic dermatitis, and staphylococcal scalded skin syndrome. Guttate psoriasis can be distinguished by history and physical exam. Further studies such as potassium hydroxide (KOH) scrapings may be helpful in ruling out the other disorders.

Le_Samuel_SANDIEGO_web.jpg

Intertrigo is an inflammatory condition of the flexural surfaces irritated by warm temperatures, friction, moisture, and poor ventilation that is commonly associated with Candida infection and/or streptococcal infection. Candidal intertrigo can present with erythematous patches or plaques in an intertriginous area that may develop erosions, macerations, fissures, crust, and weeping. Satellite papules and pustules are pathognomonic for Candida species. Streptococcal intertrigo usually presents with bright red color and may be painful or pruritic. Perianal streptococcal infection is reported as a trigger of guttate psoriasis in pediatric patients.

Pityriasis rubra pilaris is a rare inflammatory papulosquamous disorder with an unknown etiology. Red-orange papules and plaques, hyperkeratotic follicular papules, and palmoplantar hyperkeratosis are primary features. Diagnosis is based on clinical and histopathology. Pityriasis rubra pilaris is self-limited and asymptomatic in many cases. Treatment may not be required, but combination therapy with topical agents includes emollients, keratolytic agents (for example, urea, salicylic acid, alpha-hydroxy acids), topical corticosteroids, tazarotene, and topical calcineurin inhibitors. Systemic agents include oral retinoids and methotrexate.

Eichenfield_Lawrence_CA_web.jpg

Atopic dermatitis is a chronic inflammatory skin disease that involves genetic and environmental factors, leading to abnormalities in the epidermis and the immune system presenting with its typical morphology and distribution. The morphology of eczematous lesions is distinct from papulosquamous lesions of psoriasis.

Staphylococcal scalded skin syndrome is a toxin-mediated skin disorder which presents with denuded, peeling skin due to epidermolytic exotoxin producing Staphylococcus species. Fever, erythematous rash, malaise, skin pain, and irritability presents initially. Progressive desquamation with accentuation in folds is typical, with progression usually within 1-2 days. Systemic antibiotics covering Staphylococcus should be administered early. Emollients and nonadherent dressings should be applied to affected areas to promote healing. Supportive care includes dehydration management, temperature regulation, and nutrition. Skin desquamation usually occurs within 5 days with resolution within 2 weeks.

This infant displayed streptococcal intertrigo which triggered an early presentation of guttate psoriasis. The patient was managed with completion of a course of oral cephalexin, midstrength topical corticosteroids to the truncal lesions, and mild topical corticosteroids to the face and diaper area with good clinical response.
 

Danny Lee and Samuel Le serve as research fellows in the Pediatric Dermatology Division of the Department of Dermatology at the University of California San Diego and Rady Children’s Hospital, San Diego. Dr. Eichenfield is Distinguished Professor of Dermatology and Pediatrics and Vice-Chair of the Department of Dermatology at the University of California San Diego and Rady Children’s Hospital, San Diego. The authors have no relevant financial disclosures.

Suggested Reading

Leung AK et al. Childhood guttate psoriasis: An updated review. Drugs Context. 2023 Oct 23:12:2023-8-2. doi: 10.7573/dic.2023-8-2.

Galili E et al. New-onset guttate psoriasis: A long-term follow-up study. Dermatology. 2023;239(2):188-194. doi: 10.1159/000527737.

Duffin KC et al. Advances and controversies in our understanding of guttate and plaque psoriasis. J Rheumatol. 2023 Nov;50(Suppl 2):4-7. doi: 10.3899/jrheum.2023-0500.

Saleh D, Tanner LS. Guttate Psoriasis. [Updated 2023 Jul 31]. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; 2023 Jan-. Available from: www.ncbi.nlm.nih.gov/books/NBK482498/

Dupire G et al. Antistreptococcal interventions for guttate and chronic plaque psoriasis. Cochrane Database Syst Rev. 2019 Mar 5;3(3):CD011571. doi: 10.1002/14651858.CD011571.pub2.

Diagnosis: Infection-induced psoriasis (guttate-type, induced by streptococcal intertrigo)

Psoriasis is a chronic inflammatory disorder characterized by well-defined, scaly, erythematous plaques. Guttate psoriasis is a distinct variant of psoriasis that is more common in children and adolescents. Guttate psoriasis usually presents with multiple, scattered, small, drop-like (“guttate”), scaly, erythematous papules and plaques. Guttate psoriasis may be triggered by infections, most commonly recent streptococcal infections.

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The pathophysiology of psoriasis involves an interplay between genetic and environmental factors. Guttate psoriasis is a chronic T-cell–mediated inflammatory disease in which there is an altered balance between T-helper-1 (TH1) and TH2 cells, transcription factor genes, and their products. HLA B-13, B-17, and Cw6 are human leukocyte antigen alleles implicated in genetic susceptibility. It is hypothesized that streptococcal infection precipitates guttate psoriasis by streptococcal superantigen–driven activation of cutaneous lymphocyte-associated antigen (CLA)–positive lymphocytes. It has been shown that streptococcal exotoxins and streptococcal M proteins act as superantigens.

Diagnosis is often made clinically based on characteristic physical findings and a possible preceding history of streptococcal infection. In patients with streptococcal infection, culture from an appropriate site and measurement of serum antistreptococcal antibody titers (for example, anti-DNase, antihyaluronidase and antistreptolysin-O) can help. A skin biopsy is usually not necessary but may be considered.

This patient presented with intertrigo of the neck and axillae at the time of presentation with the papulosquamous rash. Culture of the intertrigo yielded 4+ Group A beta streptococcus.
 

Treatment

Although there is currently no cure for guttate psoriasis, various treatment options can relieve symptoms and clear skin lesions, and infection-triggered lesions may remit, usually within several months. However, guttate psoriasis may persist and progress to chronic plaque psoriasis. Many treatment options are based mainly on clinical trials targeted for plaque psoriasis treatment.

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For mild psoriasis, topical corticosteroids are first-line treatment. Other topical steroids include vitamin D analogs (calcipotriene), topical retinoids (tazarotene), topical calcineurin inhibitors (tacrolimus and pimecrolimus), and newer non-steroidal anti-inflammatory agents (roflumilast or tapinarof), neither approved yet in this young age group. In more severe cases, phototherapy with UVB light, traditional systemic immunosuppressive agents (methotrexate, cyclosporine) or targeted biologic therapies may be considered.
 

Differential Diagnosis

The differential diagnosis may include generalized intertrigo, pityriasis rubra pilaris, tinea corporis, atopic dermatitis, and staphylococcal scalded skin syndrome. Guttate psoriasis can be distinguished by history and physical exam. Further studies such as potassium hydroxide (KOH) scrapings may be helpful in ruling out the other disorders.

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Intertrigo is an inflammatory condition of the flexural surfaces irritated by warm temperatures, friction, moisture, and poor ventilation that is commonly associated with Candida infection and/or streptococcal infection. Candidal intertrigo can present with erythematous patches or plaques in an intertriginous area that may develop erosions, macerations, fissures, crust, and weeping. Satellite papules and pustules are pathognomonic for Candida species. Streptococcal intertrigo usually presents with bright red color and may be painful or pruritic. Perianal streptococcal infection is reported as a trigger of guttate psoriasis in pediatric patients.

Pityriasis rubra pilaris is a rare inflammatory papulosquamous disorder with an unknown etiology. Red-orange papules and plaques, hyperkeratotic follicular papules, and palmoplantar hyperkeratosis are primary features. Diagnosis is based on clinical and histopathology. Pityriasis rubra pilaris is self-limited and asymptomatic in many cases. Treatment may not be required, but combination therapy with topical agents includes emollients, keratolytic agents (for example, urea, salicylic acid, alpha-hydroxy acids), topical corticosteroids, tazarotene, and topical calcineurin inhibitors. Systemic agents include oral retinoids and methotrexate.

Eichenfield_Lawrence_CA_web.jpg

Atopic dermatitis is a chronic inflammatory skin disease that involves genetic and environmental factors, leading to abnormalities in the epidermis and the immune system presenting with its typical morphology and distribution. The morphology of eczematous lesions is distinct from papulosquamous lesions of psoriasis.

Staphylococcal scalded skin syndrome is a toxin-mediated skin disorder which presents with denuded, peeling skin due to epidermolytic exotoxin producing Staphylococcus species. Fever, erythematous rash, malaise, skin pain, and irritability presents initially. Progressive desquamation with accentuation in folds is typical, with progression usually within 1-2 days. Systemic antibiotics covering Staphylococcus should be administered early. Emollients and nonadherent dressings should be applied to affected areas to promote healing. Supportive care includes dehydration management, temperature regulation, and nutrition. Skin desquamation usually occurs within 5 days with resolution within 2 weeks.

This infant displayed streptococcal intertrigo which triggered an early presentation of guttate psoriasis. The patient was managed with completion of a course of oral cephalexin, midstrength topical corticosteroids to the truncal lesions, and mild topical corticosteroids to the face and diaper area with good clinical response.
 

Danny Lee and Samuel Le serve as research fellows in the Pediatric Dermatology Division of the Department of Dermatology at the University of California San Diego and Rady Children’s Hospital, San Diego. Dr. Eichenfield is Distinguished Professor of Dermatology and Pediatrics and Vice-Chair of the Department of Dermatology at the University of California San Diego and Rady Children’s Hospital, San Diego. The authors have no relevant financial disclosures.

Suggested Reading

Leung AK et al. Childhood guttate psoriasis: An updated review. Drugs Context. 2023 Oct 23:12:2023-8-2. doi: 10.7573/dic.2023-8-2.

Galili E et al. New-onset guttate psoriasis: A long-term follow-up study. Dermatology. 2023;239(2):188-194. doi: 10.1159/000527737.

Duffin KC et al. Advances and controversies in our understanding of guttate and plaque psoriasis. J Rheumatol. 2023 Nov;50(Suppl 2):4-7. doi: 10.3899/jrheum.2023-0500.

Saleh D, Tanner LS. Guttate Psoriasis. [Updated 2023 Jul 31]. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; 2023 Jan-. Available from: www.ncbi.nlm.nih.gov/books/NBK482498/

Dupire G et al. Antistreptococcal interventions for guttate and chronic plaque psoriasis. Cochrane Database Syst Rev. 2019 Mar 5;3(3):CD011571. doi: 10.1002/14651858.CD011571.pub2.

Following the initial presentation, the lesion was initially considered an acquired port wine stain and the child was referred for laser treatment. Upon reassessment during laser treatment a few months later, the lesion had progressed to hyper- and hypopigmented plaques with associated tissue sclerosis and bone atrophy on the mid forehead, nose, and scalp. Patches of alopecia and atrophy were observed on the frontal scalp. The diagnosis was revised to linear morphea en coup de sabre and the child was referred to pediatric rheumatology and commenced treatment with methotrexate and oral corticosteroids.

Matiz_Catalina_SanDiego.jpg

Linear morphea, a rare connective tissue disorder, primarily affects girls in the first 2 decades of life. Lesions can initially present in many ways. Usually, they present as hypo- or hyperpigmented patches, but may also present as lichenoid uncolored or pink plaques resembling lichen striatus. There may also be erythematous patches mimicking a capillary malformation, as seen in our patient. A recent article reviewing the progression of the lesions from erythematous patches to sclerosis suggests it occurs between 3 and 7 months of age. Subsequent stages manifest as significant atrophy, hypo- and hyperpigmentation, and in severe cases, bone atrophy and deformity, often causing substantial cosmetic disfigurement and functional impairment.

Pathophysiologically, linear morphea involves a complex interplay of immunologic, vascular, and fibrotic processes. While the initial triggers remain elusive, dysregulated immune responses leading to endothelial injury, subsequent activation of fibroblasts and myofibroblasts, and excessive collagen deposition are implicated. Angiogenic disturbances exacerbate tissue ischemia, perpetuating the fibrotic cascade. Alterations in cytokine signaling pathways, particularly TGF-beta and interleukin-6, play pivotal roles in promoting fibrosis and modulating the inflammatory milieu.

Diagnosis of linear morphea en coup de sabre relies on clinical examination, imaging (ultrasonography, MRI, CT scan), and skin biopsy for histopathological analysis. Imaging helps evaluate tissue involvement, while histology reveals characteristic dermal sclerosis, collagen deposition, and inflammation. Early-stage histology may show telangiectatic changes, complicating its differentiation from capillary malformation.

Treatment aims to mitigate symptoms, halt disease progression, and improve cosmesis and functionality. This involves a multidisciplinary approach with systemic medications, phototherapy, physical therapy, and surgical interventions in severe cases. Early identification is crucial for systemic treatments such as methotrexate and systemic corticosteroids to arrest disease progression. Other adjunctive therapies include topical corticosteroids, calcineurin inhibitors, and phototherapy. Surgical procedures like tissue expansion or autologous fat grafting may address tissue atrophy and deformities.

Linear morphea en coup de sabre presents diagnostic and therapeutic challenges because of its rarity and variable clinical course. Collaborative efforts among dermatologists, rheumatologists, radiologists, and surgeons are essential for accurate diagnosis, evaluation, and tailored management. Continued research into pathogenesis and novel therapeutic agents is pivotal to enhance understanding and improve outcomes for those affected by this enigmatic dermatologic condition.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Gomez-Garcia LA et al. Pediatr Dermatol. 2022 Mar;39(2):275-80.

Ng SS, Tay YK. J Cosmet Laser Ther. 2015;17(5):277-80.

Nijhawan RI et al. J Am Acad Dermatol. 2011 Apr;64(4):779-82.

Following the initial presentation, the lesion was initially considered an acquired port wine stain and the child was referred for laser treatment. Upon reassessment during laser treatment a few months later, the lesion had progressed to hyper- and hypopigmented plaques with associated tissue sclerosis and bone atrophy on the mid forehead, nose, and scalp. Patches of alopecia and atrophy were observed on the frontal scalp. The diagnosis was revised to linear morphea en coup de sabre and the child was referred to pediatric rheumatology and commenced treatment with methotrexate and oral corticosteroids.

Matiz_Catalina_SanDiego.jpg

Linear morphea, a rare connective tissue disorder, primarily affects girls in the first 2 decades of life. Lesions can initially present in many ways. Usually, they present as hypo- or hyperpigmented patches, but may also present as lichenoid uncolored or pink plaques resembling lichen striatus. There may also be erythematous patches mimicking a capillary malformation, as seen in our patient. A recent article reviewing the progression of the lesions from erythematous patches to sclerosis suggests it occurs between 3 and 7 months of age. Subsequent stages manifest as significant atrophy, hypo- and hyperpigmentation, and in severe cases, bone atrophy and deformity, often causing substantial cosmetic disfigurement and functional impairment.

Pathophysiologically, linear morphea involves a complex interplay of immunologic, vascular, and fibrotic processes. While the initial triggers remain elusive, dysregulated immune responses leading to endothelial injury, subsequent activation of fibroblasts and myofibroblasts, and excessive collagen deposition are implicated. Angiogenic disturbances exacerbate tissue ischemia, perpetuating the fibrotic cascade. Alterations in cytokine signaling pathways, particularly TGF-beta and interleukin-6, play pivotal roles in promoting fibrosis and modulating the inflammatory milieu.

Diagnosis of linear morphea en coup de sabre relies on clinical examination, imaging (ultrasonography, MRI, CT scan), and skin biopsy for histopathological analysis. Imaging helps evaluate tissue involvement, while histology reveals characteristic dermal sclerosis, collagen deposition, and inflammation. Early-stage histology may show telangiectatic changes, complicating its differentiation from capillary malformation.

Treatment aims to mitigate symptoms, halt disease progression, and improve cosmesis and functionality. This involves a multidisciplinary approach with systemic medications, phototherapy, physical therapy, and surgical interventions in severe cases. Early identification is crucial for systemic treatments such as methotrexate and systemic corticosteroids to arrest disease progression. Other adjunctive therapies include topical corticosteroids, calcineurin inhibitors, and phototherapy. Surgical procedures like tissue expansion or autologous fat grafting may address tissue atrophy and deformities.

Linear morphea en coup de sabre presents diagnostic and therapeutic challenges because of its rarity and variable clinical course. Collaborative efforts among dermatologists, rheumatologists, radiologists, and surgeons are essential for accurate diagnosis, evaluation, and tailored management. Continued research into pathogenesis and novel therapeutic agents is pivotal to enhance understanding and improve outcomes for those affected by this enigmatic dermatologic condition.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Gomez-Garcia LA et al. Pediatr Dermatol. 2022 Mar;39(2):275-80.

Ng SS, Tay YK. J Cosmet Laser Ther. 2015;17(5):277-80.

Nijhawan RI et al. J Am Acad Dermatol. 2011 Apr;64(4):779-82.

Following the initial presentation, the lesion was initially considered an acquired port wine stain and the child was referred for laser treatment. Upon reassessment during laser treatment a few months later, the lesion had progressed to hyper- and hypopigmented plaques with associated tissue sclerosis and bone atrophy on the mid forehead, nose, and scalp. Patches of alopecia and atrophy were observed on the frontal scalp. The diagnosis was revised to linear morphea en coup de sabre and the child was referred to pediatric rheumatology and commenced treatment with methotrexate and oral corticosteroids.

Matiz_Catalina_SanDiego.jpg

Linear morphea, a rare connective tissue disorder, primarily affects girls in the first 2 decades of life. Lesions can initially present in many ways. Usually, they present as hypo- or hyperpigmented patches, but may also present as lichenoid uncolored or pink plaques resembling lichen striatus. There may also be erythematous patches mimicking a capillary malformation, as seen in our patient. A recent article reviewing the progression of the lesions from erythematous patches to sclerosis suggests it occurs between 3 and 7 months of age. Subsequent stages manifest as significant atrophy, hypo- and hyperpigmentation, and in severe cases, bone atrophy and deformity, often causing substantial cosmetic disfigurement and functional impairment.

Pathophysiologically, linear morphea involves a complex interplay of immunologic, vascular, and fibrotic processes. While the initial triggers remain elusive, dysregulated immune responses leading to endothelial injury, subsequent activation of fibroblasts and myofibroblasts, and excessive collagen deposition are implicated. Angiogenic disturbances exacerbate tissue ischemia, perpetuating the fibrotic cascade. Alterations in cytokine signaling pathways, particularly TGF-beta and interleukin-6, play pivotal roles in promoting fibrosis and modulating the inflammatory milieu.

Diagnosis of linear morphea en coup de sabre relies on clinical examination, imaging (ultrasonography, MRI, CT scan), and skin biopsy for histopathological analysis. Imaging helps evaluate tissue involvement, while histology reveals characteristic dermal sclerosis, collagen deposition, and inflammation. Early-stage histology may show telangiectatic changes, complicating its differentiation from capillary malformation.

Treatment aims to mitigate symptoms, halt disease progression, and improve cosmesis and functionality. This involves a multidisciplinary approach with systemic medications, phototherapy, physical therapy, and surgical interventions in severe cases. Early identification is crucial for systemic treatments such as methotrexate and systemic corticosteroids to arrest disease progression. Other adjunctive therapies include topical corticosteroids, calcineurin inhibitors, and phototherapy. Surgical procedures like tissue expansion or autologous fat grafting may address tissue atrophy and deformities.

Linear morphea en coup de sabre presents diagnostic and therapeutic challenges because of its rarity and variable clinical course. Collaborative efforts among dermatologists, rheumatologists, radiologists, and surgeons are essential for accurate diagnosis, evaluation, and tailored management. Continued research into pathogenesis and novel therapeutic agents is pivotal to enhance understanding and improve outcomes for those affected by this enigmatic dermatologic condition.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Gomez-Garcia LA et al. Pediatr Dermatol. 2022 Mar;39(2):275-80.

Ng SS, Tay YK. J Cosmet Laser Ther. 2015;17(5):277-80.

Nijhawan RI et al. J Am Acad Dermatol. 2011 Apr;64(4):779-82.

The lesions on the heels are consistent with piezogenic pedal papules. Piezogenic pedal papules are a relatively common and underreported skin condition that can affect people of all ages, including adolescents. They seem to be more common in women and have been described in families, though a genetic link hasn’t been elucidated. PPP manifests as small, soft, compressible papules on the lateral aspects of the skin on the heels, more noticeable when the patient is standing, and can also present on the wrists and legs. While they may not be a cause for serious concern, understanding their causes, associated conditions, and management is important.

Piezogenic pedal papules are flesh-colored or slightly reddish and can range in size from a few millimeters to a centimeter or more. They are described as benign herniations of elastic tissue and subcutaneous fat through the reticular dermis. The lesions are triggered by increased pressure and compression, such as standing or the application of pressure on the heel. The exact etiology is not known. While piezogenic pedal papules are often asymptomatic, some individuals experience discomfort, itching, or mild pain, particularly when walking or applying pressure to the affected area, especially in patients with Ehlers-Danlos syndrome (EDS).

Individuals who may be at risk of developing these lesions include obese patients, individuals with pes planus, and people who have occupations that require long periods of standing. It can also be seen in athletes who participate in long-distance running or high-impact sports. Piezogenic pedal papules have been described as one of the core skin findings in patients with hypermobile Ehlers-Danlos syndrome (hEDS), which also includes skin hyperextensibility, joint hypermobility, tissue fragility with atrophic cutaneous scars, and abnormal bruising and bleeding. Our patient presented with some of these characteristics (piezogenic papules, soft elastic skin, and some joint hypermobility) but did not fulfill all the criteria for the diagnosis of hEDS or other types of EDS.

The diagnosis of hEDS is based on the 2017 diagnostic criteria checklist. To be diagnosed with hEDS, the patient may have all three parts of the diagnostic criteria. The three domains include generalized joint hypermobility (partially met by our patient), evidence of syndromic features, musculoskeletal complications, and/or family history (she had a few of these criteria, including piezogenic papules and striae), and the exclusion of alternative diagnoses (see references for the PDF checklist). As she does have some features, we diagnosed her with hypermobility spectrum disorder. There is no genetic testing available for the hypermobile spectrum disorder or the hypermobile type of EDS. Given that these patients can present with mitral valve prolapse, she was referred to a cardiac echocardiogram, which was reported as normal.

The diagnosis of PPP is made clinically, and rarely a biopsy is required. Biopsies of the lesions show hyperkeratosis, degeneration of the thin fibrous septa between fat lobules, and subsequent coalescence of fat. If the presentation is atypical, a high-frequency ultrasound can be requested to confirm the physical exam findings.

If the lesions are fixed, firm, and solitary, a diagnosis to consider is juvenile aponeurotic fibroma, which occurs more often in children and adolescents on the wrists and is less common on the ankles. If there is suspicion for this condition, a plain radiograph will show stippled calcifications.

PPP are usually asymptomatic and need no further treatment. When they are symptomatic, conservative management should be considered first, which includes behavioral modifications, weight loss, avoidance of prolonged standing, and reduced foot trauma. If these are not successful, compression socks, heel cups, and other orthotics can be recommended. Intralesional injections of betamethasone and bupivacaine have been reported as an option in patients with symptomatic PPP and a history of EDS.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested reading

Edimo CO et al. Int J Womens Dermatol. 2021 Jan. doi: 10.1016/j.ijwd.2021.01.020. Erratum in: Int J Womens Dermatol. 2021 Jul 31;7(5Part B):869-70.

Brown F, Cook C. Piezogenic Pedal Papule. 2023 Aug 16. In: StatPearls [Internet]. Treasure Island, Fla.: StatPearls Publishing, 2023. PMID: 29489228.

Levy HP. Hypermobile Ehlers-Danlos Syndrome. 2004 Oct 22 [Updated 2018 Jun 21]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993-2023. Available from: www.ncbi.nlm.nih.gov/books/NBK1279/.

The International Consortium on Ehlers-Danlos Syndrome & Related Disorders. Diagnostic Criteria for Hypermobile Ehlers-Danlos Syndrome (hEDS). www.ehlers-danlos.com/wp-content/uploads/2017/05/hEDS-Dx-Criteria-checklist-1.pdf.

The lesions on the heels are consistent with piezogenic pedal papules. Piezogenic pedal papules are a relatively common and underreported skin condition that can affect people of all ages, including adolescents. They seem to be more common in women and have been described in families, though a genetic link hasn’t been elucidated. PPP manifests as small, soft, compressible papules on the lateral aspects of the skin on the heels, more noticeable when the patient is standing, and can also present on the wrists and legs. While they may not be a cause for serious concern, understanding their causes, associated conditions, and management is important.

Piezogenic pedal papules are flesh-colored or slightly reddish and can range in size from a few millimeters to a centimeter or more. They are described as benign herniations of elastic tissue and subcutaneous fat through the reticular dermis. The lesions are triggered by increased pressure and compression, such as standing or the application of pressure on the heel. The exact etiology is not known. While piezogenic pedal papules are often asymptomatic, some individuals experience discomfort, itching, or mild pain, particularly when walking or applying pressure to the affected area, especially in patients with Ehlers-Danlos syndrome (EDS).

Individuals who may be at risk of developing these lesions include obese patients, individuals with pes planus, and people who have occupations that require long periods of standing. It can also be seen in athletes who participate in long-distance running or high-impact sports. Piezogenic pedal papules have been described as one of the core skin findings in patients with hypermobile Ehlers-Danlos syndrome (hEDS), which also includes skin hyperextensibility, joint hypermobility, tissue fragility with atrophic cutaneous scars, and abnormal bruising and bleeding. Our patient presented with some of these characteristics (piezogenic papules, soft elastic skin, and some joint hypermobility) but did not fulfill all the criteria for the diagnosis of hEDS or other types of EDS.

The diagnosis of hEDS is based on the 2017 diagnostic criteria checklist. To be diagnosed with hEDS, the patient may have all three parts of the diagnostic criteria. The three domains include generalized joint hypermobility (partially met by our patient), evidence of syndromic features, musculoskeletal complications, and/or family history (she had a few of these criteria, including piezogenic papules and striae), and the exclusion of alternative diagnoses (see references for the PDF checklist). As she does have some features, we diagnosed her with hypermobility spectrum disorder. There is no genetic testing available for the hypermobile spectrum disorder or the hypermobile type of EDS. Given that these patients can present with mitral valve prolapse, she was referred to a cardiac echocardiogram, which was reported as normal.

The diagnosis of PPP is made clinically, and rarely a biopsy is required. Biopsies of the lesions show hyperkeratosis, degeneration of the thin fibrous septa between fat lobules, and subsequent coalescence of fat. If the presentation is atypical, a high-frequency ultrasound can be requested to confirm the physical exam findings.

If the lesions are fixed, firm, and solitary, a diagnosis to consider is juvenile aponeurotic fibroma, which occurs more often in children and adolescents on the wrists and is less common on the ankles. If there is suspicion for this condition, a plain radiograph will show stippled calcifications.

PPP are usually asymptomatic and need no further treatment. When they are symptomatic, conservative management should be considered first, which includes behavioral modifications, weight loss, avoidance of prolonged standing, and reduced foot trauma. If these are not successful, compression socks, heel cups, and other orthotics can be recommended. Intralesional injections of betamethasone and bupivacaine have been reported as an option in patients with symptomatic PPP and a history of EDS.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested reading

Edimo CO et al. Int J Womens Dermatol. 2021 Jan. doi: 10.1016/j.ijwd.2021.01.020. Erratum in: Int J Womens Dermatol. 2021 Jul 31;7(5Part B):869-70.

Brown F, Cook C. Piezogenic Pedal Papule. 2023 Aug 16. In: StatPearls [Internet]. Treasure Island, Fla.: StatPearls Publishing, 2023. PMID: 29489228.

Levy HP. Hypermobile Ehlers-Danlos Syndrome. 2004 Oct 22 [Updated 2018 Jun 21]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993-2023. Available from: www.ncbi.nlm.nih.gov/books/NBK1279/.

The International Consortium on Ehlers-Danlos Syndrome & Related Disorders. Diagnostic Criteria for Hypermobile Ehlers-Danlos Syndrome (hEDS). www.ehlers-danlos.com/wp-content/uploads/2017/05/hEDS-Dx-Criteria-checklist-1.pdf.

The lesions on the heels are consistent with piezogenic pedal papules. Piezogenic pedal papules are a relatively common and underreported skin condition that can affect people of all ages, including adolescents. They seem to be more common in women and have been described in families, though a genetic link hasn’t been elucidated. PPP manifests as small, soft, compressible papules on the lateral aspects of the skin on the heels, more noticeable when the patient is standing, and can also present on the wrists and legs. While they may not be a cause for serious concern, understanding their causes, associated conditions, and management is important.

Piezogenic pedal papules are flesh-colored or slightly reddish and can range in size from a few millimeters to a centimeter or more. They are described as benign herniations of elastic tissue and subcutaneous fat through the reticular dermis. The lesions are triggered by increased pressure and compression, such as standing or the application of pressure on the heel. The exact etiology is not known. While piezogenic pedal papules are often asymptomatic, some individuals experience discomfort, itching, or mild pain, particularly when walking or applying pressure to the affected area, especially in patients with Ehlers-Danlos syndrome (EDS).

Individuals who may be at risk of developing these lesions include obese patients, individuals with pes planus, and people who have occupations that require long periods of standing. It can also be seen in athletes who participate in long-distance running or high-impact sports. Piezogenic pedal papules have been described as one of the core skin findings in patients with hypermobile Ehlers-Danlos syndrome (hEDS), which also includes skin hyperextensibility, joint hypermobility, tissue fragility with atrophic cutaneous scars, and abnormal bruising and bleeding. Our patient presented with some of these characteristics (piezogenic papules, soft elastic skin, and some joint hypermobility) but did not fulfill all the criteria for the diagnosis of hEDS or other types of EDS.

The diagnosis of hEDS is based on the 2017 diagnostic criteria checklist. To be diagnosed with hEDS, the patient may have all three parts of the diagnostic criteria. The three domains include generalized joint hypermobility (partially met by our patient), evidence of syndromic features, musculoskeletal complications, and/or family history (she had a few of these criteria, including piezogenic papules and striae), and the exclusion of alternative diagnoses (see references for the PDF checklist). As she does have some features, we diagnosed her with hypermobility spectrum disorder. There is no genetic testing available for the hypermobile spectrum disorder or the hypermobile type of EDS. Given that these patients can present with mitral valve prolapse, she was referred to a cardiac echocardiogram, which was reported as normal.

The diagnosis of PPP is made clinically, and rarely a biopsy is required. Biopsies of the lesions show hyperkeratosis, degeneration of the thin fibrous septa between fat lobules, and subsequent coalescence of fat. If the presentation is atypical, a high-frequency ultrasound can be requested to confirm the physical exam findings.

If the lesions are fixed, firm, and solitary, a diagnosis to consider is juvenile aponeurotic fibroma, which occurs more often in children and adolescents on the wrists and is less common on the ankles. If there is suspicion for this condition, a plain radiograph will show stippled calcifications.

PPP are usually asymptomatic and need no further treatment. When they are symptomatic, conservative management should be considered first, which includes behavioral modifications, weight loss, avoidance of prolonged standing, and reduced foot trauma. If these are not successful, compression socks, heel cups, and other orthotics can be recommended. Intralesional injections of betamethasone and bupivacaine have been reported as an option in patients with symptomatic PPP and a history of EDS.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested reading

Edimo CO et al. Int J Womens Dermatol. 2021 Jan. doi: 10.1016/j.ijwd.2021.01.020. Erratum in: Int J Womens Dermatol. 2021 Jul 31;7(5Part B):869-70.

Brown F, Cook C. Piezogenic Pedal Papule. 2023 Aug 16. In: StatPearls [Internet]. Treasure Island, Fla.: StatPearls Publishing, 2023. PMID: 29489228.

Levy HP. Hypermobile Ehlers-Danlos Syndrome. 2004 Oct 22 [Updated 2018 Jun 21]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993-2023. Available from: www.ncbi.nlm.nih.gov/books/NBK1279/.

The International Consortium on Ehlers-Danlos Syndrome & Related Disorders. Diagnostic Criteria for Hypermobile Ehlers-Danlos Syndrome (hEDS). www.ehlers-danlos.com/wp-content/uploads/2017/05/hEDS-Dx-Criteria-checklist-1.pdf.

Answer: A

Pityriasis alba is a common benign skin disorder that presents as hypopigmented skin most noticeable in darker skin types. It presents as whitish or mildly erythematous patches, commonly on the face, though it can appear on the trunk and extremities as well. It is estimated that about 1% of the general population is affected and may be more common after months with more extended sun exposure.

While a specific cause has not been identified, it is thought to represent post-inflammatory hypopigmentation, and is thought by many experts to be more common in atopic individuals; it is considered a minor clinical criterion for atopic dermatitis. The name relates to its appearance at times being scaly (pityriasis) and its whitish coloration (alba) and may represent a non-specific dermatitis.

It occurs predominantly in children and adolescents, and a slight male predominance has been noted. Even though this condition is not seasonal, the lesions become more obvious in the spring and summer because of sun exposure and darkening of the surrounding normal skin.

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Eichenfield_Lawrence_CA_web.jpg

Suggested reading

1. Treat: Abdel-Wahab HM and Ragaie MH. Pityriasis alba: Toward an effective treatment. J Dermatolog Treat. 2022 Jun;33(4):2285-9. doi: 10.1080/09546634.2021.1959014. Epub 2021 Aug 1.

2. PEARLS: Givler DN et al. Pityriasis alba. 2023 Feb 19. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023.

3. Choi SH et al. Pityriasis alba in pediatric patients with skin of color. J Drugs Dermatol. 2023 Apr 1;22(4):417-8. doi: 10.36849/JDD.7221.

4. Gawai SR et al. Association of pityriasis alba with atopic dermatitis: A cross-sectional study. Indian J Dermatol. 2021 Sep-Oct;66(5):567-8. doi: 10.4103/ijd.ijd_936_20.
 

Dr. Guelfand is a visiting dermatology resident in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Vuong is a clinical fellow in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Eichenfield is vice chair of the department of dermatology and distinguished professor of dermatology and pediatrics at the University of California, San Diego, and Rady Children’s Hospital, San Diego. No author has any relevant financial disclosures.

Answer: A

Pityriasis alba is a common benign skin disorder that presents as hypopigmented skin most noticeable in darker skin types. It presents as whitish or mildly erythematous patches, commonly on the face, though it can appear on the trunk and extremities as well. It is estimated that about 1% of the general population is affected and may be more common after months with more extended sun exposure.

While a specific cause has not been identified, it is thought to represent post-inflammatory hypopigmentation, and is thought by many experts to be more common in atopic individuals; it is considered a minor clinical criterion for atopic dermatitis. The name relates to its appearance at times being scaly (pityriasis) and its whitish coloration (alba) and may represent a non-specific dermatitis.

It occurs predominantly in children and adolescents, and a slight male predominance has been noted. Even though this condition is not seasonal, the lesions become more obvious in the spring and summer because of sun exposure and darkening of the surrounding normal skin.

Guelfand_Sofia_CALIF_web.jpg

Vuong_Carrie_San Diego_web.jpg

Eichenfield_Lawrence_CA_web.jpg

Suggested reading

1. Treat: Abdel-Wahab HM and Ragaie MH. Pityriasis alba: Toward an effective treatment. J Dermatolog Treat. 2022 Jun;33(4):2285-9. doi: 10.1080/09546634.2021.1959014. Epub 2021 Aug 1.

2. PEARLS: Givler DN et al. Pityriasis alba. 2023 Feb 19. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023.

3. Choi SH et al. Pityriasis alba in pediatric patients with skin of color. J Drugs Dermatol. 2023 Apr 1;22(4):417-8. doi: 10.36849/JDD.7221.

4. Gawai SR et al. Association of pityriasis alba with atopic dermatitis: A cross-sectional study. Indian J Dermatol. 2021 Sep-Oct;66(5):567-8. doi: 10.4103/ijd.ijd_936_20.
 

Dr. Guelfand is a visiting dermatology resident in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Vuong is a clinical fellow in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Eichenfield is vice chair of the department of dermatology and distinguished professor of dermatology and pediatrics at the University of California, San Diego, and Rady Children’s Hospital, San Diego. No author has any relevant financial disclosures.

Answer: A

Pityriasis alba is a common benign skin disorder that presents as hypopigmented skin most noticeable in darker skin types. It presents as whitish or mildly erythematous patches, commonly on the face, though it can appear on the trunk and extremities as well. It is estimated that about 1% of the general population is affected and may be more common after months with more extended sun exposure.

While a specific cause has not been identified, it is thought to represent post-inflammatory hypopigmentation, and is thought by many experts to be more common in atopic individuals; it is considered a minor clinical criterion for atopic dermatitis. The name relates to its appearance at times being scaly (pityriasis) and its whitish coloration (alba) and may represent a non-specific dermatitis.

It occurs predominantly in children and adolescents, and a slight male predominance has been noted. Even though this condition is not seasonal, the lesions become more obvious in the spring and summer because of sun exposure and darkening of the surrounding normal skin.

Guelfand_Sofia_CALIF_web.jpg

Vuong_Carrie_San Diego_web.jpg

Eichenfield_Lawrence_CA_web.jpg

Suggested reading

1. Treat: Abdel-Wahab HM and Ragaie MH. Pityriasis alba: Toward an effective treatment. J Dermatolog Treat. 2022 Jun;33(4):2285-9. doi: 10.1080/09546634.2021.1959014. Epub 2021 Aug 1.

2. PEARLS: Givler DN et al. Pityriasis alba. 2023 Feb 19. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023.

3. Choi SH et al. Pityriasis alba in pediatric patients with skin of color. J Drugs Dermatol. 2023 Apr 1;22(4):417-8. doi: 10.36849/JDD.7221.

4. Gawai SR et al. Association of pityriasis alba with atopic dermatitis: A cross-sectional study. Indian J Dermatol. 2021 Sep-Oct;66(5):567-8. doi: 10.4103/ijd.ijd_936_20.
 

Dr. Guelfand is a visiting dermatology resident in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Vuong is a clinical fellow in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Eichenfield is vice chair of the department of dermatology and distinguished professor of dermatology and pediatrics at the University of California, San Diego, and Rady Children’s Hospital, San Diego. No author has any relevant financial disclosures.

At the week follow-up, the lesions were unchanged and the swelling on the left lateral eyebrow was worsening. A biopsy of the yellow lesion on the back and one of the scaly papules on the abdomen was performed. A fungal and bacterial cultures were also ordered.

He was referred to ophthalmology for evaluation of the eyelid swelling and an ultrasound was requested.

The skin biopsy showed a clonal proliferation of reniform histiocytes with eosinophils within the dermis. The cells were positive for S100, CD207 (langerin), and CD1a and negative for pancytokeratin and Melan-A, supportive of the diagnosis of Langerhans cell histiocytosis (LCH).
 

Diagnosis

The patient was admitted to the hospital, where a skeletal survey was performed, which showed an asymmetric lucency involving the left frontal calvarium extending to the superior lateral orbital rim. The brain MRI demonstrated a destructive avidly enhancing soft-tissue process which involved the superior left orbital rim likely with some degree of intracranial extension. This lesion exerts mass effect upon surrounding structures to the left ocular globe. With the skin and skeletal findings, the patient was diagnosed with LCH. His blood count was significant for thrombocytopenia. His liver and kidney function were normal. His electrolytes were also with in normal range. He was started on chemotherapy with vinblastine and systemic corticosteroids with resolution of the rash and decrease on the size of the lesion on the orbit within a few weeks.

Infantile LCH is a rare neoplastic disorder of hematopoietic myeloid precursor cells caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway, particularly BRAF-V600E mutation. White male children are mostly affected, with a peak incidence of 1-3 years of age. Nine out of 10 children with cutaneous involvement also have multisystemic disease, such as the case of our patient. LCH is classified as single or multisystem organ disease. Two-thirds of the cases present with single system involvement. Organs most commonly affected include the bone (the skull being the most commonly affected), skin, and high-risk organs like the liver, spleen, and bone marrow, and less commonly the lungs, lymph nodes, and central nervous system. Some patients can present with fever, lethargy, and weight loss. None were noted in our patient.

Skin findings of LCH can have multiple morphologies and presentations and often described as a big mimicker. In young infants like our patient, the seborrheic dermatitis–mimicking type is often seen. In other cases, the skin lesions can appear eczematous, petechial, with scabbing, crusting, or purpura. Xanthoma-like lesions, like that one our patient had in the back, have also been described. Resistant diaper dermatitis and cradle cap should prompt the clinician to think about LCH. Lesions can be so varied that can present with hypopigmentation (vitiligo like), hyperpigmentation, varicella-like papulo-pustules, and red blue nodules within others. Oral mucosa and nail involvement can also occur.

Bone involvement can present as soft-tissue mass with swelling and pain as it occur in our patient.

Endocrinopathies have been described in patients with LCH including diabetes insipidus, growth hormone deficiency, and less likely thyroid disease.
 

Multidisciplinary care

The diagnosis of LCH in infants necessitates a combination of clinical, radiological, and histopathologic findings. In infants, cutaneous involvement is a frequent initial presentation, with characteristic lesions that are often misdiagnosed as other dermatologic conditions. Timely recognition of these lesions and appropriate skin biopsies for histological examination are essential steps in achieving an accurate diagnosis.

Radiological imaging, including x-rays, CT, and MRI, plays a crucial role in assessing the extent of involvement.

The management of LCH in infants requires a well-coordinated multidisciplinary approach involving pediatric oncologists, dermatologists, radiologists, orthopedic surgeons, and other relevant specialists. Treatment strategies vary depending on the extent of disease involvement and the presence of risk factors. In localized cases, observation with close monitoring may be considered, as some cases of LCH in infants may undergo spontaneous regression. However, cases with severe symptoms, extensive organ involvement, or high-risk features may require systemic therapies.

Matiz_Catalina_SanDiego.jpg

Chemotherapy agents, including vinblastine and prednisone have been utilized in the treatment of infantile LCH with varying success. The selection of treatment regimens should be tailored to each individual case, considering disease severity, potential toxicities, and long-term effects. In cases of bone lesions causing significant deformities or functional impairment, surgical intervention may be necessary. Skin only disease can be treated with topical corticosteroids.
 

Prognosis

Survival rates in patients with single-organ involvement without risk-organ involvement is close to 100% and with risk-organ involvement of 98% at 5 years.

Long-term follow-up is essential for infants diagnosed with LCH, as recurrence and late effects can occur even after successful treatment. Continued monitoring allows for the timely detection of relapses or the development of secondary complications.

Infants thought to have common skin conditions like eczema, seborrheic dermatitis, or diaper dermatitis not responding to treatment should be referred to pediatric dermatology for evaluation to rule out the possibility of LCH.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1035-44.

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1047-56.

Leung AKC et al. World J Pediatr. 2019 Dec;15(6):536-45.

At the week follow-up, the lesions were unchanged and the swelling on the left lateral eyebrow was worsening. A biopsy of the yellow lesion on the back and one of the scaly papules on the abdomen was performed. A fungal and bacterial cultures were also ordered.

He was referred to ophthalmology for evaluation of the eyelid swelling and an ultrasound was requested.

The skin biopsy showed a clonal proliferation of reniform histiocytes with eosinophils within the dermis. The cells were positive for S100, CD207 (langerin), and CD1a and negative for pancytokeratin and Melan-A, supportive of the diagnosis of Langerhans cell histiocytosis (LCH).
 

Diagnosis

The patient was admitted to the hospital, where a skeletal survey was performed, which showed an asymmetric lucency involving the left frontal calvarium extending to the superior lateral orbital rim. The brain MRI demonstrated a destructive avidly enhancing soft-tissue process which involved the superior left orbital rim likely with some degree of intracranial extension. This lesion exerts mass effect upon surrounding structures to the left ocular globe. With the skin and skeletal findings, the patient was diagnosed with LCH. His blood count was significant for thrombocytopenia. His liver and kidney function were normal. His electrolytes were also with in normal range. He was started on chemotherapy with vinblastine and systemic corticosteroids with resolution of the rash and decrease on the size of the lesion on the orbit within a few weeks.

Infantile LCH is a rare neoplastic disorder of hematopoietic myeloid precursor cells caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway, particularly BRAF-V600E mutation. White male children are mostly affected, with a peak incidence of 1-3 years of age. Nine out of 10 children with cutaneous involvement also have multisystemic disease, such as the case of our patient. LCH is classified as single or multisystem organ disease. Two-thirds of the cases present with single system involvement. Organs most commonly affected include the bone (the skull being the most commonly affected), skin, and high-risk organs like the liver, spleen, and bone marrow, and less commonly the lungs, lymph nodes, and central nervous system. Some patients can present with fever, lethargy, and weight loss. None were noted in our patient.

Skin findings of LCH can have multiple morphologies and presentations and often described as a big mimicker. In young infants like our patient, the seborrheic dermatitis–mimicking type is often seen. In other cases, the skin lesions can appear eczematous, petechial, with scabbing, crusting, or purpura. Xanthoma-like lesions, like that one our patient had in the back, have also been described. Resistant diaper dermatitis and cradle cap should prompt the clinician to think about LCH. Lesions can be so varied that can present with hypopigmentation (vitiligo like), hyperpigmentation, varicella-like papulo-pustules, and red blue nodules within others. Oral mucosa and nail involvement can also occur.

Bone involvement can present as soft-tissue mass with swelling and pain as it occur in our patient.

Endocrinopathies have been described in patients with LCH including diabetes insipidus, growth hormone deficiency, and less likely thyroid disease.
 

Multidisciplinary care

The diagnosis of LCH in infants necessitates a combination of clinical, radiological, and histopathologic findings. In infants, cutaneous involvement is a frequent initial presentation, with characteristic lesions that are often misdiagnosed as other dermatologic conditions. Timely recognition of these lesions and appropriate skin biopsies for histological examination are essential steps in achieving an accurate diagnosis.

Radiological imaging, including x-rays, CT, and MRI, plays a crucial role in assessing the extent of involvement.

The management of LCH in infants requires a well-coordinated multidisciplinary approach involving pediatric oncologists, dermatologists, radiologists, orthopedic surgeons, and other relevant specialists. Treatment strategies vary depending on the extent of disease involvement and the presence of risk factors. In localized cases, observation with close monitoring may be considered, as some cases of LCH in infants may undergo spontaneous regression. However, cases with severe symptoms, extensive organ involvement, or high-risk features may require systemic therapies.

Matiz_Catalina_SanDiego.jpg

Chemotherapy agents, including vinblastine and prednisone have been utilized in the treatment of infantile LCH with varying success. The selection of treatment regimens should be tailored to each individual case, considering disease severity, potential toxicities, and long-term effects. In cases of bone lesions causing significant deformities or functional impairment, surgical intervention may be necessary. Skin only disease can be treated with topical corticosteroids.
 

Prognosis

Survival rates in patients with single-organ involvement without risk-organ involvement is close to 100% and with risk-organ involvement of 98% at 5 years.

Long-term follow-up is essential for infants diagnosed with LCH, as recurrence and late effects can occur even after successful treatment. Continued monitoring allows for the timely detection of relapses or the development of secondary complications.

Infants thought to have common skin conditions like eczema, seborrheic dermatitis, or diaper dermatitis not responding to treatment should be referred to pediatric dermatology for evaluation to rule out the possibility of LCH.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1035-44.

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1047-56.

Leung AKC et al. World J Pediatr. 2019 Dec;15(6):536-45.

At the week follow-up, the lesions were unchanged and the swelling on the left lateral eyebrow was worsening. A biopsy of the yellow lesion on the back and one of the scaly papules on the abdomen was performed. A fungal and bacterial cultures were also ordered.

He was referred to ophthalmology for evaluation of the eyelid swelling and an ultrasound was requested.

The skin biopsy showed a clonal proliferation of reniform histiocytes with eosinophils within the dermis. The cells were positive for S100, CD207 (langerin), and CD1a and negative for pancytokeratin and Melan-A, supportive of the diagnosis of Langerhans cell histiocytosis (LCH).
 

Diagnosis

The patient was admitted to the hospital, where a skeletal survey was performed, which showed an asymmetric lucency involving the left frontal calvarium extending to the superior lateral orbital rim. The brain MRI demonstrated a destructive avidly enhancing soft-tissue process which involved the superior left orbital rim likely with some degree of intracranial extension. This lesion exerts mass effect upon surrounding structures to the left ocular globe. With the skin and skeletal findings, the patient was diagnosed with LCH. His blood count was significant for thrombocytopenia. His liver and kidney function were normal. His electrolytes were also with in normal range. He was started on chemotherapy with vinblastine and systemic corticosteroids with resolution of the rash and decrease on the size of the lesion on the orbit within a few weeks.

Infantile LCH is a rare neoplastic disorder of hematopoietic myeloid precursor cells caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway, particularly BRAF-V600E mutation. White male children are mostly affected, with a peak incidence of 1-3 years of age. Nine out of 10 children with cutaneous involvement also have multisystemic disease, such as the case of our patient. LCH is classified as single or multisystem organ disease. Two-thirds of the cases present with single system involvement. Organs most commonly affected include the bone (the skull being the most commonly affected), skin, and high-risk organs like the liver, spleen, and bone marrow, and less commonly the lungs, lymph nodes, and central nervous system. Some patients can present with fever, lethargy, and weight loss. None were noted in our patient.

Skin findings of LCH can have multiple morphologies and presentations and often described as a big mimicker. In young infants like our patient, the seborrheic dermatitis–mimicking type is often seen. In other cases, the skin lesions can appear eczematous, petechial, with scabbing, crusting, or purpura. Xanthoma-like lesions, like that one our patient had in the back, have also been described. Resistant diaper dermatitis and cradle cap should prompt the clinician to think about LCH. Lesions can be so varied that can present with hypopigmentation (vitiligo like), hyperpigmentation, varicella-like papulo-pustules, and red blue nodules within others. Oral mucosa and nail involvement can also occur.

Bone involvement can present as soft-tissue mass with swelling and pain as it occur in our patient.

Endocrinopathies have been described in patients with LCH including diabetes insipidus, growth hormone deficiency, and less likely thyroid disease.
 

Multidisciplinary care

The diagnosis of LCH in infants necessitates a combination of clinical, radiological, and histopathologic findings. In infants, cutaneous involvement is a frequent initial presentation, with characteristic lesions that are often misdiagnosed as other dermatologic conditions. Timely recognition of these lesions and appropriate skin biopsies for histological examination are essential steps in achieving an accurate diagnosis.

Radiological imaging, including x-rays, CT, and MRI, plays a crucial role in assessing the extent of involvement.

The management of LCH in infants requires a well-coordinated multidisciplinary approach involving pediatric oncologists, dermatologists, radiologists, orthopedic surgeons, and other relevant specialists. Treatment strategies vary depending on the extent of disease involvement and the presence of risk factors. In localized cases, observation with close monitoring may be considered, as some cases of LCH in infants may undergo spontaneous regression. However, cases with severe symptoms, extensive organ involvement, or high-risk features may require systemic therapies.

Matiz_Catalina_SanDiego.jpg

Chemotherapy agents, including vinblastine and prednisone have been utilized in the treatment of infantile LCH with varying success. The selection of treatment regimens should be tailored to each individual case, considering disease severity, potential toxicities, and long-term effects. In cases of bone lesions causing significant deformities or functional impairment, surgical intervention may be necessary. Skin only disease can be treated with topical corticosteroids.
 

Prognosis

Survival rates in patients with single-organ involvement without risk-organ involvement is close to 100% and with risk-organ involvement of 98% at 5 years.

Long-term follow-up is essential for infants diagnosed with LCH, as recurrence and late effects can occur even after successful treatment. Continued monitoring allows for the timely detection of relapses or the development of secondary complications.

Infants thought to have common skin conditions like eczema, seborrheic dermatitis, or diaper dermatitis not responding to treatment should be referred to pediatric dermatology for evaluation to rule out the possibility of LCH.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1035-44.

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1047-56.

Leung AKC et al. World J Pediatr. 2019 Dec;15(6):536-45.

Given the characteristic clinical presentation, the most likely diagnosis is pilomatrixoma.

Pilomatrixomas are benign adnexal tumors that arise from immature matrix cells of the hair follicles located on dermal or subcutaneous tissue.

The cause of pilomatrixoma remains unclear. Recent studies have suggested that the development of pilomatrixoma are related to mutations in the Wnt signaling pathway, where beta-catenin gene (CTNNB1) mutation is the most frequently reported.^1-4

Pilomatrixomas are more common in children and often present before 10 years of age.^1,2,5 They commonly appear in head and neck, as well as upper extremities, trunk, and lower extremities.^2,6

The clinical manifestations of pilomatrixomas are diverse and according to their appearance five classic clinical types are described: mass, pigmented, mixed, ulcerated, and keloid-like.^2,3 The mass type is the predominant form, where it generally presents as a hard and freely mobile nodule covered by skin that may present a firm calcified protruding nodule. Other less common types include: lymphangiectasic, anetodermic, perforating, and bullous.^2,6,7

Eichenfield_Lawrence_CA_web.jpg

Pilomatrixomas are mostly solitary, whereas multiple forms are reported to be associated with familial inheritance or syndromic conditions, such as myotonic dystrophy, Gardner syndrome, Turner’s syndrome, and Rubinstein-Taybi syndrome.^2-4 However, children and adolescents occasionally present with multiple pilomatricomas with no associated syndrome.

On physical exam a helpful features for the diagnosis is the “teeter-totter sign,” which can be illustrated by pressing on one edge of the lesion that will cause the opposite edge to protrude from the skin. Another helpful tool is to use a light to transilluminate and the calcification produces a bluish opaque hue,⁸ as light cannot transmit through the calcification, often differentiating it from epidermal inclusion cysts or other noncalcified lesions.
 

What is the differential diagnosis?

Because of the diverse clinical presentations, pilomatrixomas are frequently misdiagnosed. The percentage of correct preoperative diagnosis reported is low, varying from 16% to 43% in different series.^1,9-11 They most frequently are misdiagnosed as other types of cysts such as epidermal, dermoid, or sebaceous.^2,3,5,12,13 Rapidly growing pilomatrixomas can be also be misdiagnosed as malignant soft-tissue tumors, cutaneous lymphoma, or sarcomas.^5,13

AlNabti_Alreem_CALIF_web.jpg

When presenting with a classic history and physical features, diagnosis is clinical, and no further studies are recommended.¹⁴ To improve diagnostic accuracy when encountering unusual subtypes, imaging is recommended, including ultrasound. Ultrasound adds a high positive predictive value (95.56%).² Generally, on ultrasound a pilomatrixoma is described as an oval, well-defined, heterogeneous, hyperechoic subcutaneous mass with or without posterior shadowing.² The definitive diagnosis is, however, made by histopathologic examination.

Pilomatrixomas do not spontaneously regress, therefore complete surgical resection is the standard treatment. During the follow-up period, very low recurrence rates have been reported, varying from 1.5% to 2% which generally occurs because of incomplete resection.^2,3

Guelfand_Sofia_CALIF_web.jpg

Plexiform neurofibromas are usually congenital tumors of peripheral nerve sheath associated with neurofibromatosis type 1, often with a “bag of worms” feel on palpation. Epidermoid cysts generally present as dermal nodules often with a visible puncture, mobile on soft and mobile on palpation. Dermatofibromas present as firm, usually hyperpigmented papule or nodules that are fixed to subcutaneous tissue, thus often “dimpling” when pitched. Dermatofibrosarcoma protuberans is a rare soft-tissue sarcoma which presents as a firm, slow growing indurated plaques growing over months to years.
 

Conclusion

Pilomatrixomas are a benign adnexal tumor that sometimes can present as atypical forms such as this case. Diagnosis is usually based on clinical diagnosis, and transillumination can be a bedside clue. When the clinical diagnosis remains obscure an ultrasound can be helpful. The main aim of this case is to improve awareness of the variable presentations of pilomatrixomas and the importance of high level of suspicion supported by careful clinical evaluation.

Dr. Eichenfield is vice chair of the department of dermatology and professor of dermatology and pediatrics at the University of California, San Diego, and Rady Children’s Hospital, San Diego. Dr. Al-Nabti is a clinical fellow in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Guelfand is a visiting dermatology resident in the division of pediaric and adolescent dermatology, University of Califonia, San Diego.

References

1. Jones CD et al. Am J Dermatopathol. 2018;40:631-41.

2. Hu JL et al. Arch Craniofac Surg. 2020;21(5):288-93.

3. Adhikari G and Jadhav GS. Cureus. 2022;14(2):22228.

4. Cóbar JP et al. J Surg Case Rep. 2023;2023(4):rjad182.

5. Schwarz Y et al. Int J Pediatr Otorhinolaryngol. 2016;85:148-53.

6. Kose D et al. J Cancer Res Ther. 2014;10(3):549-51.

7. Sabater-Abad J et al. Dermatol Online J. 2020;26(8):13030/qt4h16s45w.

8. Alkatan HM et al. Int J Surg Case Rep. 2021;84:106068.

9. Pant I et al. Indian J Dermatol. 2010;55:390-2.

10. Kaddu S et al. Am J Dermatopathol. 1996;18(4):333-8

11. Schwarz Y et al. Int J Pediatr Otorhinolaryngol. 2016;85:148-53.

12. Wang YN et al. Chin Med J (Engl). 2021;134(16):2011-2.

13. Yannoutsos A et al. Am J Dermatopathol. 2018;40(9):690-3.

14. Zhao A et al. Ear Nose Throat J. 2021;1455613211044778.

Given the characteristic clinical presentation, the most likely diagnosis is pilomatrixoma.

Pilomatrixomas are benign adnexal tumors that arise from immature matrix cells of the hair follicles located on dermal or subcutaneous tissue.

The cause of pilomatrixoma remains unclear. Recent studies have suggested that the development of pilomatrixoma are related to mutations in the Wnt signaling pathway, where beta-catenin gene (CTNNB1) mutation is the most frequently reported.^1-4

Pilomatrixomas are more common in children and often present before 10 years of age.^1,2,5 They commonly appear in head and neck, as well as upper extremities, trunk, and lower extremities.^2,6

The clinical manifestations of pilomatrixomas are diverse and according to their appearance five classic clinical types are described: mass, pigmented, mixed, ulcerated, and keloid-like.^2,3 The mass type is the predominant form, where it generally presents as a hard and freely mobile nodule covered by skin that may present a firm calcified protruding nodule. Other less common types include: lymphangiectasic, anetodermic, perforating, and bullous.^2,6,7

Eichenfield_Lawrence_CA_web.jpg

Pilomatrixomas are mostly solitary, whereas multiple forms are reported to be associated with familial inheritance or syndromic conditions, such as myotonic dystrophy, Gardner syndrome, Turner’s syndrome, and Rubinstein-Taybi syndrome.^2-4 However, children and adolescents occasionally present with multiple pilomatricomas with no associated syndrome.

On physical exam a helpful features for the diagnosis is the “teeter-totter sign,” which can be illustrated by pressing on one edge of the lesion that will cause the opposite edge to protrude from the skin. Another helpful tool is to use a light to transilluminate and the calcification produces a bluish opaque hue,⁸ as light cannot transmit through the calcification, often differentiating it from epidermal inclusion cysts or other noncalcified lesions.
 

What is the differential diagnosis?

Because of the diverse clinical presentations, pilomatrixomas are frequently misdiagnosed. The percentage of correct preoperative diagnosis reported is low, varying from 16% to 43% in different series.^1,9-11 They most frequently are misdiagnosed as other types of cysts such as epidermal, dermoid, or sebaceous.^2,3,5,12,13 Rapidly growing pilomatrixomas can be also be misdiagnosed as malignant soft-tissue tumors, cutaneous lymphoma, or sarcomas.^5,13

AlNabti_Alreem_CALIF_web.jpg

When presenting with a classic history and physical features, diagnosis is clinical, and no further studies are recommended.¹⁴ To improve diagnostic accuracy when encountering unusual subtypes, imaging is recommended, including ultrasound. Ultrasound adds a high positive predictive value (95.56%).² Generally, on ultrasound a pilomatrixoma is described as an oval, well-defined, heterogeneous, hyperechoic subcutaneous mass with or without posterior shadowing.² The definitive diagnosis is, however, made by histopathologic examination.

Pilomatrixomas do not spontaneously regress, therefore complete surgical resection is the standard treatment. During the follow-up period, very low recurrence rates have been reported, varying from 1.5% to 2% which generally occurs because of incomplete resection.^2,3

Guelfand_Sofia_CALIF_web.jpg

Plexiform neurofibromas are usually congenital tumors of peripheral nerve sheath associated with neurofibromatosis type 1, often with a “bag of worms” feel on palpation. Epidermoid cysts generally present as dermal nodules often with a visible puncture, mobile on soft and mobile on palpation. Dermatofibromas present as firm, usually hyperpigmented papule or nodules that are fixed to subcutaneous tissue, thus often “dimpling” when pitched. Dermatofibrosarcoma protuberans is a rare soft-tissue sarcoma which presents as a firm, slow growing indurated plaques growing over months to years.
 

Conclusion

Pilomatrixomas are a benign adnexal tumor that sometimes can present as atypical forms such as this case. Diagnosis is usually based on clinical diagnosis, and transillumination can be a bedside clue. When the clinical diagnosis remains obscure an ultrasound can be helpful. The main aim of this case is to improve awareness of the variable presentations of pilomatrixomas and the importance of high level of suspicion supported by careful clinical evaluation.

Dr. Eichenfield is vice chair of the department of dermatology and professor of dermatology and pediatrics at the University of California, San Diego, and Rady Children’s Hospital, San Diego. Dr. Al-Nabti is a clinical fellow in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Guelfand is a visiting dermatology resident in the division of pediaric and adolescent dermatology, University of Califonia, San Diego.

References

1. Jones CD et al. Am J Dermatopathol. 2018;40:631-41.

2. Hu JL et al. Arch Craniofac Surg. 2020;21(5):288-93.

3. Adhikari G and Jadhav GS. Cureus. 2022;14(2):22228.

4. Cóbar JP et al. J Surg Case Rep. 2023;2023(4):rjad182.

5. Schwarz Y et al. Int J Pediatr Otorhinolaryngol. 2016;85:148-53.

6. Kose D et al. J Cancer Res Ther. 2014;10(3):549-51.

7. Sabater-Abad J et al. Dermatol Online J. 2020;26(8):13030/qt4h16s45w.

8. Alkatan HM et al. Int J Surg Case Rep. 2021;84:106068.

9. Pant I et al. Indian J Dermatol. 2010;55:390-2.

10. Kaddu S et al. Am J Dermatopathol. 1996;18(4):333-8

11. Schwarz Y et al. Int J Pediatr Otorhinolaryngol. 2016;85:148-53.

12. Wang YN et al. Chin Med J (Engl). 2021;134(16):2011-2.

13. Yannoutsos A et al. Am J Dermatopathol. 2018;40(9):690-3.

14. Zhao A et al. Ear Nose Throat J. 2021;1455613211044778.

Given the characteristic clinical presentation, the most likely diagnosis is pilomatrixoma.

Pilomatrixomas are benign adnexal tumors that arise from immature matrix cells of the hair follicles located on dermal or subcutaneous tissue.

The cause of pilomatrixoma remains unclear. Recent studies have suggested that the development of pilomatrixoma are related to mutations in the Wnt signaling pathway, where beta-catenin gene (CTNNB1) mutation is the most frequently reported.^1-4

Pilomatrixomas are more common in children and often present before 10 years of age.^1,2,5 They commonly appear in head and neck, as well as upper extremities, trunk, and lower extremities.^2,6

The clinical manifestations of pilomatrixomas are diverse and according to their appearance five classic clinical types are described: mass, pigmented, mixed, ulcerated, and keloid-like.^2,3 The mass type is the predominant form, where it generally presents as a hard and freely mobile nodule covered by skin that may present a firm calcified protruding nodule. Other less common types include: lymphangiectasic, anetodermic, perforating, and bullous.^2,6,7

Eichenfield_Lawrence_CA_web.jpg

Pilomatrixomas are mostly solitary, whereas multiple forms are reported to be associated with familial inheritance or syndromic conditions, such as myotonic dystrophy, Gardner syndrome, Turner’s syndrome, and Rubinstein-Taybi syndrome.^2-4 However, children and adolescents occasionally present with multiple pilomatricomas with no associated syndrome.

On physical exam a helpful features for the diagnosis is the “teeter-totter sign,” which can be illustrated by pressing on one edge of the lesion that will cause the opposite edge to protrude from the skin. Another helpful tool is to use a light to transilluminate and the calcification produces a bluish opaque hue,⁸ as light cannot transmit through the calcification, often differentiating it from epidermal inclusion cysts or other noncalcified lesions.
 

What is the differential diagnosis?

Because of the diverse clinical presentations, pilomatrixomas are frequently misdiagnosed. The percentage of correct preoperative diagnosis reported is low, varying from 16% to 43% in different series.^1,9-11 They most frequently are misdiagnosed as other types of cysts such as epidermal, dermoid, or sebaceous.^2,3,5,12,13 Rapidly growing pilomatrixomas can be also be misdiagnosed as malignant soft-tissue tumors, cutaneous lymphoma, or sarcomas.^5,13

AlNabti_Alreem_CALIF_web.jpg

When presenting with a classic history and physical features, diagnosis is clinical, and no further studies are recommended.¹⁴ To improve diagnostic accuracy when encountering unusual subtypes, imaging is recommended, including ultrasound. Ultrasound adds a high positive predictive value (95.56%).² Generally, on ultrasound a pilomatrixoma is described as an oval, well-defined, heterogeneous, hyperechoic subcutaneous mass with or without posterior shadowing.² The definitive diagnosis is, however, made by histopathologic examination.

Pilomatrixomas do not spontaneously regress, therefore complete surgical resection is the standard treatment. During the follow-up period, very low recurrence rates have been reported, varying from 1.5% to 2% which generally occurs because of incomplete resection.^2,3

Guelfand_Sofia_CALIF_web.jpg

Plexiform neurofibromas are usually congenital tumors of peripheral nerve sheath associated with neurofibromatosis type 1, often with a “bag of worms” feel on palpation. Epidermoid cysts generally present as dermal nodules often with a visible puncture, mobile on soft and mobile on palpation. Dermatofibromas present as firm, usually hyperpigmented papule or nodules that are fixed to subcutaneous tissue, thus often “dimpling” when pitched. Dermatofibrosarcoma protuberans is a rare soft-tissue sarcoma which presents as a firm, slow growing indurated plaques growing over months to years.
 

Conclusion

Pilomatrixomas are a benign adnexal tumor that sometimes can present as atypical forms such as this case. Diagnosis is usually based on clinical diagnosis, and transillumination can be a bedside clue. When the clinical diagnosis remains obscure an ultrasound can be helpful. The main aim of this case is to improve awareness of the variable presentations of pilomatrixomas and the importance of high level of suspicion supported by careful clinical evaluation.

Dr. Eichenfield is vice chair of the department of dermatology and professor of dermatology and pediatrics at the University of California, San Diego, and Rady Children’s Hospital, San Diego. Dr. Al-Nabti is a clinical fellow in the division of pediatric and adolescent dermatology, University of California, San Diego. Dr. Guelfand is a visiting dermatology resident in the division of pediaric and adolescent dermatology, University of Califonia, San Diego.

References

1. Jones CD et al. Am J Dermatopathol. 2018;40:631-41.

2. Hu JL et al. Arch Craniofac Surg. 2020;21(5):288-93.

3. Adhikari G and Jadhav GS. Cureus. 2022;14(2):22228.

4. Cóbar JP et al. J Surg Case Rep. 2023;2023(4):rjad182.

5. Schwarz Y et al. Int J Pediatr Otorhinolaryngol. 2016;85:148-53.

6. Kose D et al. J Cancer Res Ther. 2014;10(3):549-51.

7. Sabater-Abad J et al. Dermatol Online J. 2020;26(8):13030/qt4h16s45w.

8. Alkatan HM et al. Int J Surg Case Rep. 2021;84:106068.

9. Pant I et al. Indian J Dermatol. 2010;55:390-2.

10. Kaddu S et al. Am J Dermatopathol. 1996;18(4):333-8

11. Schwarz Y et al. Int J Pediatr Otorhinolaryngol. 2016;85:148-53.

12. Wang YN et al. Chin Med J (Engl). 2021;134(16):2011-2.

13. Yannoutsos A et al. Am J Dermatopathol. 2018;40(9):690-3.

14. Zhao A et al. Ear Nose Throat J. 2021;1455613211044778.

Given the presentation and the unique location of the lesions he was diagnosed with follicular keratosis of the chin (FKC).

This is a rare and poorly understood condition that can be present in older children and young teenagers. In the cases reported by Kanzaki et al.¹ were two boys who presented with the condition; it was thought to be associated with rubbing of the chin with their hands when watching TV or reading. The author described improvement with habit change. This condition is usually described in boys, and some cases presented in brothers,² suggesting a genetic predisposition. Some reports lack a history of rubbing or trauma to the area.

Histopathologic evaluation of the lesions demonstrates dilated hair follicles containing keratotic basophilic material without any signs of inflammation.

Matiz_Catalina_SanDiego.jpg

The lesions can be confused with keratosis pilaris (KP). Keratosis pilaris can be described in association with atopic dermatitis and ichthyosis, which were not present in our patient. The lesions usually present on the sides of the cheeks and lateral region of the arms and legs. Compared with follicular keratosis, KP lesions usually present with associated perifollicular erythema. Our patient did not present with lesions on the cheeks or the sides of the arms or legs. Milia can present on the chin of children, usually if there is history of rubbing or trauma, or on a scar. Milia are micro keratin cysts, usually seen in areas of the face. Lichen spinulous is described as rough small follicular papules that present in oval or circular patches that can grow up to 5 cm and spread rapidly. They usually present on the extensor surfaces of the extremities, neck, abdomen, and knees. These lesions are thought to be secondary to infections, have been associated with atopy, and have been seen in patients with atopic dermatitis. There is a probable genetic predisposition. The lesions are usually treated with gentle soaps and moisturizer containing keratolytics like urea or salicylic acid, and in some cases topical retinoids can also be tried. Follicular mucinosis can also present similarly to keratosis follicularis. The lesions present as scaly plaques or as grouped skin color papules on the face, scalp, or the neck that can also be associated with hair loss. Sometimes a biopsy needs to be done to be able to distinguish it from follicular keratosis. There is an increase of mucin around hair follicles and sebaceous glands with associated inflammation and degeneration of the follicular structures. In patients with primary follicular mucinosis the lesions can resolve spontaneously in a couple of years. Lesions can be treated with topical corticosteroids, oral antibiotics like macrolides or tetracyclines, dapsone, and phototherapy.

KFC can be treated with vitamin D analogues. It is usually unresponsive to corticosteroids, keratolytic lotions, and retinoids. Our patient was prescribed calcipotriene.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego

References

1. Kanzaki T et al. J Am Acad Dermatol. 1992;26(1):134-5.

2. Buechner AA et al. JAMA Dermatol. 2018 Jan 1;154(1):111-2.

Given the presentation and the unique location of the lesions he was diagnosed with follicular keratosis of the chin (FKC).

This is a rare and poorly understood condition that can be present in older children and young teenagers. In the cases reported by Kanzaki et al.¹ were two boys who presented with the condition; it was thought to be associated with rubbing of the chin with their hands when watching TV or reading. The author described improvement with habit change. This condition is usually described in boys, and some cases presented in brothers,² suggesting a genetic predisposition. Some reports lack a history of rubbing or trauma to the area.

Histopathologic evaluation of the lesions demonstrates dilated hair follicles containing keratotic basophilic material without any signs of inflammation.

Matiz_Catalina_SanDiego.jpg

The lesions can be confused with keratosis pilaris (KP). Keratosis pilaris can be described in association with atopic dermatitis and ichthyosis, which were not present in our patient. The lesions usually present on the sides of the cheeks and lateral region of the arms and legs. Compared with follicular keratosis, KP lesions usually present with associated perifollicular erythema. Our patient did not present with lesions on the cheeks or the sides of the arms or legs. Milia can present on the chin of children, usually if there is history of rubbing or trauma, or on a scar. Milia are micro keratin cysts, usually seen in areas of the face. Lichen spinulous is described as rough small follicular papules that present in oval or circular patches that can grow up to 5 cm and spread rapidly. They usually present on the extensor surfaces of the extremities, neck, abdomen, and knees. These lesions are thought to be secondary to infections, have been associated with atopy, and have been seen in patients with atopic dermatitis. There is a probable genetic predisposition. The lesions are usually treated with gentle soaps and moisturizer containing keratolytics like urea or salicylic acid, and in some cases topical retinoids can also be tried. Follicular mucinosis can also present similarly to keratosis follicularis. The lesions present as scaly plaques or as grouped skin color papules on the face, scalp, or the neck that can also be associated with hair loss. Sometimes a biopsy needs to be done to be able to distinguish it from follicular keratosis. There is an increase of mucin around hair follicles and sebaceous glands with associated inflammation and degeneration of the follicular structures. In patients with primary follicular mucinosis the lesions can resolve spontaneously in a couple of years. Lesions can be treated with topical corticosteroids, oral antibiotics like macrolides or tetracyclines, dapsone, and phototherapy.

KFC can be treated with vitamin D analogues. It is usually unresponsive to corticosteroids, keratolytic lotions, and retinoids. Our patient was prescribed calcipotriene.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego

References

1. Kanzaki T et al. J Am Acad Dermatol. 1992;26(1):134-5.

2. Buechner AA et al. JAMA Dermatol. 2018 Jan 1;154(1):111-2.

Given the presentation and the unique location of the lesions he was diagnosed with follicular keratosis of the chin (FKC).

This is a rare and poorly understood condition that can be present in older children and young teenagers. In the cases reported by Kanzaki et al.¹ were two boys who presented with the condition; it was thought to be associated with rubbing of the chin with their hands when watching TV or reading. The author described improvement with habit change. This condition is usually described in boys, and some cases presented in brothers,² suggesting a genetic predisposition. Some reports lack a history of rubbing or trauma to the area.

Histopathologic evaluation of the lesions demonstrates dilated hair follicles containing keratotic basophilic material without any signs of inflammation.

Matiz_Catalina_SanDiego.jpg

The lesions can be confused with keratosis pilaris (KP). Keratosis pilaris can be described in association with atopic dermatitis and ichthyosis, which were not present in our patient. The lesions usually present on the sides of the cheeks and lateral region of the arms and legs. Compared with follicular keratosis, KP lesions usually present with associated perifollicular erythema. Our patient did not present with lesions on the cheeks or the sides of the arms or legs. Milia can present on the chin of children, usually if there is history of rubbing or trauma, or on a scar. Milia are micro keratin cysts, usually seen in areas of the face. Lichen spinulous is described as rough small follicular papules that present in oval or circular patches that can grow up to 5 cm and spread rapidly. They usually present on the extensor surfaces of the extremities, neck, abdomen, and knees. These lesions are thought to be secondary to infections, have been associated with atopy, and have been seen in patients with atopic dermatitis. There is a probable genetic predisposition. The lesions are usually treated with gentle soaps and moisturizer containing keratolytics like urea or salicylic acid, and in some cases topical retinoids can also be tried. Follicular mucinosis can also present similarly to keratosis follicularis. The lesions present as scaly plaques or as grouped skin color papules on the face, scalp, or the neck that can also be associated with hair loss. Sometimes a biopsy needs to be done to be able to distinguish it from follicular keratosis. There is an increase of mucin around hair follicles and sebaceous glands with associated inflammation and degeneration of the follicular structures. In patients with primary follicular mucinosis the lesions can resolve spontaneously in a couple of years. Lesions can be treated with topical corticosteroids, oral antibiotics like macrolides or tetracyclines, dapsone, and phototherapy.

KFC can be treated with vitamin D analogues. It is usually unresponsive to corticosteroids, keratolytic lotions, and retinoids. Our patient was prescribed calcipotriene.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego

References

1. Kanzaki T et al. J Am Acad Dermatol. 1992;26(1):134-5.

2. Buechner AA et al. JAMA Dermatol. 2018 Jan 1;154(1):111-2.

The Diagnosis: Alopecic and Aseptic Nodule of the Scalp

Alopecic and aseptic nodule of the scalp (AANS) is an underdiagnosed condition presenting with one or few inflammatory nodules on the scalp with overlying nonscarring alopecia. The nodules can be soft, fluctuant, or firm and are characterized by negative fungal and bacterial stains as well as cultures.¹ Trichoscopic features such as black or yellow dots, fine vellus hairs, and broken hairs have been reported.^1-3 Dilated follicular openings may be seen and are termed the Eastern pancake sign, as they resemble the bubble cavities formed during the cooking of atayef.² The histologic features of AANS often are nonspecific but show a nodular or pseudocystic, lymphohistiocytic to acute inflammatory component centered in the dermis.¹ Granulomatous inflammation or isolated giant cells have been reported within the deep dermis.^1,4 In our patient, histopathology revealed admixed acute and granulomatous inflammation within the deep dermis (Figure). Treatment of AANS includes oral antibiotics such as doxycycline, intralesional corticosteroids, or excision.¹

CT111005244_AB.jpg

Although the etiology of AANS currently is unclear, a process of follicular plugging or a deep folliculitis sparing the bulge stem cells has been theorized. Young males are disproportionately affected.¹ It is uncertain how much overlap there is, if any, between AANS and pseudocyst of the scalp, the latter of which primarily is reported in the Japanese literature and demonstrates alopecic nodules between the forehead and vertex of the scalp with pseudocystic architecture and granulomatous infiltration on histopathology.^4-7

There are several clinical and histologic differences between AANS and other diagnoses in the differential. Dermoid cysts tend to present at birth, with 70% of cases presenting before the age of 6 years, and without overlying skin changes.⁸ They represent a benign entrapment of ectoderm along embryonic closure lines during development.⁹ Histologic examination typically will show a squamous-lined cyst within the dermis with associated adnexal structures.¹⁰ Cylindromas are benign neoplasms of eccrine sweat glands named after the histologic presentation of cylinder-shaped basaloid cell populations when cross-sectioned.^11,12 When cylindromas coalesce on the scalp, they form a distinctive morphology sometimes loosely resembling a turban, giving them the previously more common name turban tumors.^11,13 Cylindromas appear as slow-growing protuberant tumors that are erythematous or flesh colored. Cylindromas are 9 times more common in females.13 Pilar cysts have a stratified squamous epithelium lining with a palisaded outer layer and are derived from the outer root sheath of hair follicles.¹⁴ Clinically, pilar cysts are smooth mobile cysts that favor skin with a dense concentration of hair follicles.^14,15 On palpation, pilar cysts are firm due to their keratinous contents and typically are nontender unless inflamed.¹⁵ Lipomas are benign mesenchymal tumors with mature adipocytes that often appear as subcutaneous nodules without overlying skin changes, though they can involve deep fascia. On palpation, lipomas generally are soft, mobile, and nontender.¹⁶

The Diagnosis: Alopecic and Aseptic Nodule of the Scalp

Alopecic and aseptic nodule of the scalp (AANS) is an underdiagnosed condition presenting with one or few inflammatory nodules on the scalp with overlying nonscarring alopecia. The nodules can be soft, fluctuant, or firm and are characterized by negative fungal and bacterial stains as well as cultures.¹ Trichoscopic features such as black or yellow dots, fine vellus hairs, and broken hairs have been reported.^1-3 Dilated follicular openings may be seen and are termed the Eastern pancake sign, as they resemble the bubble cavities formed during the cooking of atayef.² The histologic features of AANS often are nonspecific but show a nodular or pseudocystic, lymphohistiocytic to acute inflammatory component centered in the dermis.¹ Granulomatous inflammation or isolated giant cells have been reported within the deep dermis.^1,4 In our patient, histopathology revealed admixed acute and granulomatous inflammation within the deep dermis (Figure). Treatment of AANS includes oral antibiotics such as doxycycline, intralesional corticosteroids, or excision.¹

CT111005244_AB.jpg

Although the etiology of AANS currently is unclear, a process of follicular plugging or a deep folliculitis sparing the bulge stem cells has been theorized. Young males are disproportionately affected.¹ It is uncertain how much overlap there is, if any, between AANS and pseudocyst of the scalp, the latter of which primarily is reported in the Japanese literature and demonstrates alopecic nodules between the forehead and vertex of the scalp with pseudocystic architecture and granulomatous infiltration on histopathology.^4-7

There are several clinical and histologic differences between AANS and other diagnoses in the differential. Dermoid cysts tend to present at birth, with 70% of cases presenting before the age of 6 years, and without overlying skin changes.⁸ They represent a benign entrapment of ectoderm along embryonic closure lines during development.⁹ Histologic examination typically will show a squamous-lined cyst within the dermis with associated adnexal structures.¹⁰ Cylindromas are benign neoplasms of eccrine sweat glands named after the histologic presentation of cylinder-shaped basaloid cell populations when cross-sectioned.^11,12 When cylindromas coalesce on the scalp, they form a distinctive morphology sometimes loosely resembling a turban, giving them the previously more common name turban tumors.^11,13 Cylindromas appear as slow-growing protuberant tumors that are erythematous or flesh colored. Cylindromas are 9 times more common in females.13 Pilar cysts have a stratified squamous epithelium lining with a palisaded outer layer and are derived from the outer root sheath of hair follicles.¹⁴ Clinically, pilar cysts are smooth mobile cysts that favor skin with a dense concentration of hair follicles.^14,15 On palpation, pilar cysts are firm due to their keratinous contents and typically are nontender unless inflamed.¹⁵ Lipomas are benign mesenchymal tumors with mature adipocytes that often appear as subcutaneous nodules without overlying skin changes, though they can involve deep fascia. On palpation, lipomas generally are soft, mobile, and nontender.¹⁶

The Diagnosis: Alopecic and Aseptic Nodule of the Scalp

Alopecic and aseptic nodule of the scalp (AANS) is an underdiagnosed condition presenting with one or few inflammatory nodules on the scalp with overlying nonscarring alopecia. The nodules can be soft, fluctuant, or firm and are characterized by negative fungal and bacterial stains as well as cultures.¹ Trichoscopic features such as black or yellow dots, fine vellus hairs, and broken hairs have been reported.^1-3 Dilated follicular openings may be seen and are termed the Eastern pancake sign, as they resemble the bubble cavities formed during the cooking of atayef.² The histologic features of AANS often are nonspecific but show a nodular or pseudocystic, lymphohistiocytic to acute inflammatory component centered in the dermis.¹ Granulomatous inflammation or isolated giant cells have been reported within the deep dermis.^1,4 In our patient, histopathology revealed admixed acute and granulomatous inflammation within the deep dermis (Figure). Treatment of AANS includes oral antibiotics such as doxycycline, intralesional corticosteroids, or excision.¹

CT111005244_AB.jpg

Although the etiology of AANS currently is unclear, a process of follicular plugging or a deep folliculitis sparing the bulge stem cells has been theorized. Young males are disproportionately affected.¹ It is uncertain how much overlap there is, if any, between AANS and pseudocyst of the scalp, the latter of which primarily is reported in the Japanese literature and demonstrates alopecic nodules between the forehead and vertex of the scalp with pseudocystic architecture and granulomatous infiltration on histopathology.^4-7

There are several clinical and histologic differences between AANS and other diagnoses in the differential. Dermoid cysts tend to present at birth, with 70% of cases presenting before the age of 6 years, and without overlying skin changes.⁸ They represent a benign entrapment of ectoderm along embryonic closure lines during development.⁹ Histologic examination typically will show a squamous-lined cyst within the dermis with associated adnexal structures.¹⁰ Cylindromas are benign neoplasms of eccrine sweat glands named after the histologic presentation of cylinder-shaped basaloid cell populations when cross-sectioned.^11,12 When cylindromas coalesce on the scalp, they form a distinctive morphology sometimes loosely resembling a turban, giving them the previously more common name turban tumors.^11,13 Cylindromas appear as slow-growing protuberant tumors that are erythematous or flesh colored. Cylindromas are 9 times more common in females.13 Pilar cysts have a stratified squamous epithelium lining with a palisaded outer layer and are derived from the outer root sheath of hair follicles.¹⁴ Clinically, pilar cysts are smooth mobile cysts that favor skin with a dense concentration of hair follicles.^14,15 On palpation, pilar cysts are firm due to their keratinous contents and typically are nontender unless inflamed.¹⁵ Lipomas are benign mesenchymal tumors with mature adipocytes that often appear as subcutaneous nodules without overlying skin changes, though they can involve deep fascia. On palpation, lipomas generally are soft, mobile, and nontender.¹⁶