How is etiology of non-TB mycobacterial infections?

NTM may be fast or slow growing (unlike TB which is slow) grows days to weeks there are almost 100 NTMs, most common ones are M.avium, M.kansaii, M.abscessus acquired by inhalation of infected aerosols, living in closed quarters, coughing and not using face masks are risk factors Advanced age, immunosupression and corticosteroids are also risk factors. Usually settle in lower airways, sometimes make inflammatory reaction with influx of lymphocytes which may cause pneumonia.