Leukoderma punctatum following systemic PUVA therapy

A 35‐year‐old woman with vitiligo vulgaris had been treated with psoralen plus UVA (PUVA) therapy for 15 months. She was given 4,5′,8‐trimethylpsoralen (0.6 mg/kg 3 days/week) and UVA exposure (UV 7001 K Waldmann PUVA chamber). She developed repigmentation over more than 50% of the vitiliginous area over a period of 1 year. During the last 6 months, she developed three to four episodes of acute phototoxic reactions, and UVA exposure had to be interrupted. This phototoxic response was probably partly due to excessive UV radiation exposure of the lesions on exposed sites as a result of the natural bright sunshine in India. On regular monthly assessment, numerous tiny hypopigmented macules, round to oval in shape with sharp margins and measuring about 1.5 mm, were distributed over the repigmented areas ( Fig. 1). The lesions were predominantly seen over the extremities and were distributed randomly without any perifollicular or marginal predilection. Considering the typical morphology and distribution of the lesions, a clinical diagnosis of leukoderma punctatum was made and a skin biopsy was taken from one such lesion. On histopathology examination, patchy loss of melanin in the basal layer was observed without any other remarkable change in the epidermis. Figure 1 Multiple, discrete, hypopigmented, punctiform macules measuring about 1–1.5 mm over the thigh