Nontuberculous mycobacterial pulmonary infection among lung transplant recipients

Objectives: Data are limited regarding the clinical significance of nontuberculous mycobacteria pulmonary infections among lung transplant recipients. We investigated the incidence and characteristics of pulmonary nontuberculous mycobacteria infection in our lung transplant patient population. Materials and Methods: We obtained data of the patients who underwent lung transplant in our center from January 1997 to March 2019. Results: Of 690 patients, nontuberculous mycobacteria were identified in 58 patients (8.4%) over a median follow-up of 3 years. Types of species were as follows: Mycobacterium simiae (n = 24), avium complex (n = 12), abscessus (n = 9), fortuitum (n = 6), chelonae (n = 2), szulgai (n = 1), kansasii (n = 1), lentiflavum (n = 1), and undefined mycobacteria (n = 2). When we compared infections in the early versus late period posttransplant (before and after 6 months), infections with Mycobacterium simiae (16 vs 8 incidents) and Mycobacterium fortuitum (5 vs 1 incident) were more often observed within the early period, whereas most Mycobacterium abscessus (7 vs 1 incident) and Mycobacterium avium complex (9 vs 3 incidents) were observed in the later period. The median forced expiratory volume in 1 second over time did not differ significantly between patients with and without nontuberculous mycobacteria infection (P = .29). Nontuberculous mycobacteria acquisition was significantly associated with decreased survival (relative risk of 2.41, 95% CI, 1.70-3.43; P < .001). Conclusions: The nontuberculous mycobacteria species isolated varied according to the time elapsed since transplant. Among lung transplant recipients, nontuberculous mycobacteria infection was associated with increased mortality but not with lung dysfunction.