Mycobacterium avium complex infection mimicking Pott's disease in an immunocompetent adult

Mycobacterium avium complex (MAC) causes disseminated infection in patients with AIDS but rarely affects immunocompetent hosts. Among adults with underlying chronic lung disease, MAC causes indolent pulmonary infections, whereas cervical lymphadenitis or, rarely, disseminated disease affects otherwise healthy children [1]. Multifocal osteomyelitis due to MAC has been reported in immunocompetent children [2-4], but unifocal osteomyelitis in the absence of penetrating trauma is extremely rare. Igram et al. [5] recently described the case of a 39-year-old man with MAC-induced vertebral osteomyelitis whose illness was clinically indistinguishable from M. tuberculosis-induced Pott's disease. We report a case of MAC-induced vertebral osteomyelitis with late relapse in an immunocompetent host.