Nationwide evaluation of treatment outcomes and survival of patients with non-tuberculous mycobacterial pulmonary disease

BACKGROUND Treatment outcomes and long-term survival of non-tuberculous mycobacterial pulmonary disease (NTM-PD) in a real-world setting are difficult to assess, especially for species other than Mycobacterium avium complex (MAC). METHODS This was a retrospective cohort study on all Croatian residents with respiratory NTM isolates from 2006 to 2015, with follow-up to 2020. RESULTS Therapy was started in 98/137 (71.5%) of patients, significantly more often in patients with fibrocavitary disease and/or sputum smear positivity. Unsuccessful treatment outcomes were recorded in 39/98 (39.8%) patients (14 deaths and 25 treatment failures). One-year and 5-year all-cause mortality were respectively 18.2% and 37.6%. Guideline-based treatment (GBT) was started in 50/98 (51%) of treated patients and followed for the recommended duration in 35.7% (35/98). This resulted in a higher chance of cure (OR 3.79, 95% CI 1.29 to 11.1; P = 0.012) than inadequately treated/untreated patients. For Mycobacterium xenopi disease, high cure rates (>80%) were achieved both with GBT and non-GBT treatment regimens. CONCLUSION Guideline-based therapy resulted in a four-time higher chance of being cured. The impact of GBT on treatment outcomes was clear for MAC disease, but no apparent effect was observed for patients with M. xenopi disease.