Hyperkeratotic scaly lesions.

A 4-year-old boy presented with mildly itchy hyperkeratotic scaly lesions on pressure points like knees, elbows, buttocks and ankles in a bilateral symmetrical manner for two months (Fig. 1). Parents also complained of recent onset lethargy and diarrhea for three weeks. Child and parents both were known to be HIVseropositive and were on anti-retroviral therapy. Rest of the mucocutaneous examination was unremarkable, except for oral candidiasis. Tinea incognito, atopic dermatitis and acquired zinc deficiency were considered as differential diagnoses. In atopic dermatitis, the lesions are itchy, predominantly over flexors (on extensors in infants) and are accompanied by other features e.g. hyperlinearity of palms, Dannie Morgan folds, generalized xerosis, follicular papules, and history of atopy. These findings were absent in our patient. HIV status of baby, asymptomatic psoriasiform scaly plaques over pressure/trauma prone areas, absence of features of inflammation and concurrent diarrhea were clinical clues for a diagnosis of acquired hypozincemia in a HIV patient. KOH mount from the scaly lesions were negative for fungus and histopathology revealed psoriasiform acanthosis, confluent parakeratosis and mild neutrophilic infiltration. The epidermis was notable for pallor of upper layers and few dyskeratotic keratinocytes. These findings were consistent with the diagnosis of acquired hypozincemia. Serum zinc level could not be estimated, but alkaline phosphatase level was marginally low (82 IU/L). He was treated with oral zinc at a dose of 2 mg/kg/ day and emollient (and clotrimazole mouth paint for oral candidiasis). On follow up visit after two weeks, the cutaneous lesions and diarrhea were completely improved (Fig. 1). The parents were counseled about including zinc-rich food items in diet.