Otitis media and mastoiditis due to Mycobacterium fortuitum: case report, review of four cases, and a cautionary note.

Mycobacterium fortuitum is a rarely reported cause of otitis media and mastoiditis. We report such a case recently seen at our institution and review the four previously published cases of this disease entity. Amikacin is recommended in the current medical literature as empirical treatment of disease due to M. fortuitum, but the isolate from our patient showed high-level resistance to amikacin, which is rare in clinical isolates of this species; this resistance was probably related to prior treatment with topical aminoglycosides. Our patient's infection responded to a 12-month course of therapy with clarithromycin and trimethoprim-sulfamethoxazole.