[Diagnosis and treatment of atypical mycobacterial infections of the respiratory tract].

INTRODUCTION: Non tuberculous mycobacteria (NTM), unlike tuberculous mycobacteria, are not strictly human pathogens. The diagnosis of infection and the choice of treatment remain difficult.

BACKGROUND: Evidence of a NTM in a pulmonary sample is not synonymous with infection. The diagnosis depends on the association of clinical, radiological and microbiological factors. If a NTM is isolated from a respiratory sample, the probability of infection depends on the species. The main NTMs responsible for pulmonary infection in France are Mycobacterium avium intracellulare, Mycobacterium xenopi, Mycobacterium kansasi and Mycobacterium abscessus. Their management is difficult and poorly understood. Treatment is well established for M. avium intracellulare and M. kansasii, with combinations of clarithromycin-rifampicin-ethambutol and isoniazid-rifampicin-ethambutol respectively. For M. xenopi, the optimal treatment is not known and a combination of clarithromycin-rifampicin-ethambutol, with moxifloxacin as an alternative, is currently recommended. In general, treatment is prolonged and often associated with problems of tolerance.

VIEWPOINT AND CONCLUSION: The management of NTM infection, taking into account of the increase in patients "at risk", is an important issue. Further studies are needed to improve the criteria for infection and to find the optimal therapeutic combinations.