Nontuberculous mycobacteria in patients with bronchiectasis: data from the German Bronchiectasis Registry PROGNOSIS

Background: The relevance of nontuberculous mycobacteria (NTM) among subjects with bronchiectasis in Germany is unknown. In this regard, the German Bronchiectasis Registry PROGNOSIS is an excellent opportunity to provide further insights. Methods: We analyzed the first consecutively recruited and validated 1000 baseline datasets of PROGNOSIS and compared subjects with a history of NTM and/or a positive respiratory culture at baseline (NTM group) to subjects without such history and no isolation (non-NTM group). Differences between groups were assessed by univariate analysis. Results: Overall, only 56% received AFB cultures at baseline. Among 49 subjects with a positive culture MAC (76%), M. kansasii (14%) and M. gordonae (12%) were the most frequent NTM species. Using the above definition we identified 73 NTM patients (7.3%). Those were older (mean age 63 vs. 59 years; P=0.041), more often female (69 vs. 59%, P=0.11) and had a lower median BMI (23.1 vs. 24.2 kg/m²; P=0.046). Upper airway involvement, PCD as an etiology and ICS use was less frequent (18 vs. 34%, P=0.004; 3 vs. 9%, P=0.055; and 3 vs. 19%, P Conclusion: Patients with bronchiectasis and NTM exhibit distinct clinical features. Comparing our findings to those of the US Bronchiectasis Research Registry we found similarities and differences, which warrant further investigation by multivariate analysis.