Extrapulmonary NTM infections are caused by a number of different NTM species. To diagnose an NTM infection from an extrapulmonary site, you would usually isolate it from an area showing signs of inflammation using a sterile biopsy procedure. Tissue or fluid aspirate are preferred, as a wound swab often does not yield enough sample for an accurate culture. As with pulmonary NTM infection, an acid-fast bacilli (AFB) smear and culture would be the diagnostic culture used.
In addition to post-surgical outbreaks, many of which have occurred in recent years due to contaminated heater-cooler units or to medical tourism, there have been other reported infections and outbreaks of infection from places such as nail salons, eye surgery centers, and dental clinics. (In nail salon outbreaks where patients had received pedicures, a higher number of those infected had shaved their legs within 48 hours of getting a pedicure.)
As with pulmonary NTM infections, treatment with multiple antibiotics is needed for an extended period of time. Though some patients who get extrapulmonary NTM infections are immunocompromised, not all of them are, and it may be a matter of direct exposure. In all cases, tissue debridement and/or removal of any implanted prosthetic or device, is necessary.