Nontuberculous mycobacteria (NTM) are a vast group of organisms that are widespread in the environment (table 1). They have been isolated from numerous environmental sources, including water and soil. NTM can cause a broad range of infections that vary depending on the particular NTM species and on the host’s immune status. In immunocompetent individuals, disease can present as pneumonia, lymphadenitis, or skin, soft tissue, and/or bone infection. Immunocompromised individuals can also present with any of these findings, but disease in such patients may also manifest as disseminated infection. Since NTM are seldom considered as a possible etiology in infections of the soft tissues and/or bones, delays in diagnosis are common.
The epidemiology, pathogenesis, clinical manifestations, and diagnosis of osteomyelitis due to NTM will be reviewed here. The treatment of osteomyelitis due to NTM is discussed separately. (See "Treatment of osteomyelitis due to nontuberculous mycobacteria in adults".)
Other manifestations of NTM infections, as well as osteomyelitis due to bacteria and Mycobacterium tuberculosis are also discussed separately. (See "Epidemiology of nontuberculous mycobacterial infections" and "Microbiology of nontuberculous mycobacteria" and "Overview of nontuberculous mycobacteria (excluding MAC) in HIV-infected patients" and "Mycobacterium avium complex (MAC) infections in HIV-infected patients" and "Rapidly growing mycobacterial infections in HIV-negative patients" and "Overview of osteomyelitis in adults" and "Pathogenesis of osteomyelitis" and "Approach to imaging modalities in the setting of suspected osteomyelitis" and "Hematogenous osteomyelitis in children: Epidemiology, pathogenesis, and microbiology" and "Hematogenous osteomyelitis in adults" and "Vertebral osteomyelitis and discitis" and "Skeletal tuberculosis".)
Osteomyelitis is a rare manifestation of nontuberculous mycobacteria (NTM) infection, which may occur in immunocompetent and immunocompromised hosts. A wide range of NTM species can cause osteomyelitis, including both the rapidly and slowly growing mycobacteria. Osteomyelitis caused by NTM species can result from environmental exposure or nosocomial exposure and has involved either penetrating injuries or postsurgical infections, such as sternal wound infections; such cases typically occur in immunocompetent hosts [1-3].
NTM infections are commonly associated with HIV infection. M. haemophilum, M. avium complex, and M. kansasii have been the most common pathogens reported in cases of HIV-associated NTM osteomyelitis, and usually occur in the setting of disseminated disease . Most cases have occurred in the setting of advanced AIDS and a CD4 count <100 cells/microL.