DermaDiagnosis
As Girl Grows, Lesions Follow Suit
A 12-year-old African-American girl had lesions on her trunk since shortly after birth. Her pediatrician was confident that she would "outgrow"...
ANSWER
The correct answer is seborrheic dermatitis (choice “d”).
Psoriasis (choice “a”) can manifest in a similar fashion but would also appear elsewhere (eg, the elbows, knees, or nails). The scaling seen with psoriasis is usually white on a salmon-colored base and much coarser.
Vitiligo (choice “b”) presents with total, porcelain-white depigmentation and is not scaly at all; this patient’s loss of pigment was only partial.
Rashes like this are often thought to be fungal, but a fungal infection (choice “c”) is rarely seen on the face and would not demonstrate this exact pattern.
DISCUSSION
Seborrheic dermatitis (SD) is an extremely common papulosquamous skin condition that manifests primarily in oil-rich areas, such as the central face, scalp (dandruff), and in and behind the ears. On white skin, it yields a pinkish-brown scaly rash, but on darker skin, SD causes partial depigmentation—sometimes to an alarming extent. The distribution in this case is typical, with nasolabial, glabellar, ear, and brow involvement.
SD might be caused by a number of factors, some related to climate or genetics. One prevailing theory is that it involves an inflammatory reaction resulting from commensal yeast organisms (Malassezia furfur) feeding on sebum. In this case, the contribution of stress was clear.
TREATMENT/PROGNOSIS
Treatment comprised daily use of ketoconazole shampoo on the scalp and face and a topical ketoconazole cream. The condition cleared within two weeks. Although the chances of a recurrence are quite high, the patient is now armed with information and products to avoid the worst effects.
