Mycobacterium gordonae infection of the hand

A 70-year-old woman was seen for two chronic nodules on the dorsum of her left hand. They had a uniquely mamillated surface, but histopathologically showed nonspecific granulomatous changes with no organisms seen. Laboratory studies disclosed the lesions were due to Mycobacterium gordonae, an organism commonly ignored as a pathogen. The histopathologic changes were reproduced by intradermal testing with tuberculin. The lesions, unaffected by ketoconazole, as well as by a variety of antibiotics, including minocycline hydrochloride, slowly involuted during a one-year period. To our knowledge, this patient is the first documented case of cutaneous infection from this organism. Mycobacterium gordonae must be added to the list of true mycobacterial pathogens.