Erythema induratum--a type of cutaneous tuberculosis.

We report a case of erythema induratum recently encountered in our centre. A 14-year-old male presented with history of fever, weight loss and multiple, painful, hyperpigmented patches over both legs and dorsum of foot, since six months. FNAC showed evidence of granulomatous inflammation. Biopsy of the lesion showed skin with inflammatory infiltrate in the deep dermis composed predominantly of epithelioid granulomas, Langhan's giant cells and mature lymphocytes. A strongly positive Mantoux test and elevated TB IgG and IgM antibody levels suggested tuberculosis. The patient responded well to a course of anti-tuberculous therapy with marked resolution of the lesions.