This 52-year-old woman presented with a 2½-year history of a pruritic rash on her face and extremities. She had been told it was atopic dermatitis, and she had been treated with topical triamcinolone cream. She denied any history of exposure.
Answer: Atopic dermatitisSee the full case at Consultant360
A biopsy confirmed the diagnosis of atopic dermatitis, also called eczema. The circular lesions were nummular eczema, which has the appearance of a dermatophyte infection (tinea or ringworm). She was placed on a nonsteroidal agent (pimecrolimus) so as to avoid corticosteroid-induced dermal atrophy.
No specific triggers could be identified for this patient’s atopic dermatitis, other than her being perimenopausal.
It would be unusual for contact dermatitis to persist as long as this patient’s case and for the lesions to be that localized. Lupus erythematosus is a reasonable consideration and would require a biopsy. Dermatophyte infection typically would not be that widespread in an otherwise healthy person. Granuloma annulare is not pruritic and lacks scale.
David L. Kaplan, MD, is a clinical assistant professor of dermatology at the University of Missouri–Kansas City School of Medicine in Kansas City, Missouri, and at the University of Kansas School of Medicine in Kansas City, Kansas. He practices adult and pediatric dermatology in Overland Park, Kansas.