[Cutaneous tuberculosis. Report of one case].

Tuberculosis is uncommonly located in the skin, corresponding to 1 to 2% of extrapulmonary forms. We report a 61-year-old woman, referred due to a two months history of erythematous plaques covered with honey-colored crusts in the left preauricular region and below the chin. The lesions were previously treated as pyoderma with poor response. She was otherwise healthy, without any other symptom. Skin biopsy showed exudative tuberculoid granulomas with caseation necrosis. Koch culture was positive for Mycobacterium tuberculosis. Complementary studies ruled out other foci. Lupus vulgaris was diagnosed and antituberculous therapy started, achieving regression of cutaneous lesions.