Bullous erythema nodosum leprosum: a case report from Nepal.

A patient with lepromatous leprosy, while on WHO multidrug therapy (MDT) for multibacillary disease, was diagnosed as having dapsone syndrome with recurrent episodes of bullous lesions on the lower extremities for 4-5 years. The lesions were associated with high-grade fever. Examination revealed multiple hypopigmented macules on the limbs. Multiple atrophic scars were also found on the buttocks and lower limbs. Bilateral ulnar, radial cutaneous and lateral popliteal nerves were thickened. On day 10 of WHO-MB-MDT he developed a flaccid bulla on the lower leg. Skin slit smear showed a bacterial index (BI) of 3+ and the histopathology was consistent with type II reaction. High dose corticosteroid therapy was started but he continued to have new lesions, and was therefore referred to a centre where thalidomide was available. Clinical response was good and he remained symptom-free after gradual reduction in dosage. ENL should be differentiated from bullous drug reactions, pemphigus vulgaris, bullous pemphigoid and other blistering diseases.