Treatment and outcomes in patients with non-TB mycobacterial pulmonary disease: a single-centre study

BACKGROUND: In Denmark, information on treatment and outcomes of non-TB mycobacterial pulmonary disease (NTM-PD) are limited. We aimed to evaluate treatment and clinical outcomes in patients with pulmonary NTM isolates.

METHODS: We conducted a retrospective cohort study of all patients with pulmonary NTM isolates, except Mycobacterium gordonae alone, from 2016 to 2021 in the Central Region of Denmark. Clinical data were manually extracted from hospital records. Treatment outcomes (NTM-NET definitions) were assessed in treated patients, while culture conversion and mortality were evaluated in all patients.

RESULTS: Among 164 patients (median age 70 years; 48.1% male), 54.3% received antibiotic therapy, and 30% of patients meeting diagnostic criteria were not treated. Most treated patients (87.6%) were prescribed an ethambutol-macrolide-rifamycin regimen; few received intravenous (n = 1) or second-line drugs (n = 14), despite high rates of cavitary disease (>50%). Only 53.9% achieved a favourable outcome. Culture conversion within 12 months of the first positive NTM culture was associated with lower all-cause mortality (P < 0.001). All-cause mortality was 11% at 1 year and 25% at 3 years.

CONCLUSION: To improve outcomes for NTM-PD patients, improved microbiological monitoring, guideline adherence, individualised therapy for high-risk patients, consideration of prolonged or intensified therapy, and better treatment regimens are needed.