Answer to last month's Clinical Quiz

Question:
This 18 years old student presented with recurrent, intensely pruritic round patches of weeping skin lesions, that had been present for three years. The distribution was extensive over the trunk and limbs. The lesions only partially responded to a potent topical steroid and they kept on recurring. He had a past history of atopic dermatitis in childhood.

Answer:
B. Discoid (nummular) eczema

Discoid (nummular) eczema usually presents as acute or subacute dermatitis with multiple pruritic coin-shaped lesions. In the acute phase, excoriations, vesicles, exudation and crusts are common. Local experience shows that it is more common in adolescents and young patients. Both limbs and trunk can be involved, but lower limbs are most commonly affected. The individual lesion can be very resistant to treatment, and the disease usually keeps on recurring for years. In chronic case, it may be misdiagnosed as psoriasis or tinea corporis. Treatments consist of potent topical steroids, oral antihistamines and diluted potassium permanganate (1:8000) soak for the acute phase. Topical or systemic antibiotics should be given if there are signs suggestive of secondary bacterial infection. In severe cases, a short course of low dose systemic steroid is often helpful, at least temporarily. Phototherapy may be tried in refractory patients.