Variability in the Management of Adults With Pulmonary Nontuberculous Mycobacterial Disease

Abstract

Background: The increasing global prevalence of pulmonary nontuberculous mycobacteria (NTM) disease has called attention to challenges in NTM diagnosis and management. This study was conducted to understand management and outcomes of patients with pulmonary NTM disease at diverse centers across the United States.

Methods: We conducted a 10-year (2005-2015) retrospective study at 7 Vaccine and Treatment Evaluation Units to evaluate pulmonary NTM treatment outcomes in human immunodeficiency virus-negative adults. Demographic and clinical information was abstracted through medical record review. Microbiologic and clinical cure were evaluated using previously defined criteria.

Results: Of 297 patients diagnosed with pulmonary NTM, the most frequent NTM species were Mycobacterium avium-intracellulare complex (83.2%), M. kansasii (7.7%), and M. abscessus (3.4%). Two hundred forty-five (82.5%) patients received treatment, while 45 (15.2%) were followed without treatment. Eighty-six patients had available drug susceptibility results; of these, >40% exhibited resistance to rifampin, ethambutol, or amikacin. Of the 138 patients with adequate outcome data, 78 (56.5%) experienced clinical and/or microbiologic cure. Adherence to the American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) treatment guidelines was significantly more common in patients who were cured (odds ratio, 4.5, 95% confidence interval, 2.0-10.4; P < .001). Overall mortality was 15.7%.

Conclusions: Despite ATS/IDSA Guidelines, management of pulmonary NTM disease was heterogeneous and cure rates were relatively low. Further work is required to understand which patients are suitable for monitoring without treatment and the impact of antimicrobial therapy on pulmonary NTM morbidity and mortality.

Keywords: Mycobacterium avium complex; lung; mortality; mycobacteria; treatment outcome.

Figure 1.

Schematic of total medical records reviewed and the number of patients with pulmonary NTM who were negative for HIV analyzed for different outcome measures. Abbreviations: HIV, human immunodeficiency virus; NTM, nontuberculous mycobacteria; PNTM, pulmonary nontuberculous mycobacteria.

Figure 2.

Kaplan-Meier estimate of survival of patients with pulmonary NTM. Overall survival is shown for patients with pulmonary NTM based on sex (A) and presence or absence of cavitation on imaging studies (B). Male patients compared with female patients and patients with cavitation compared with those without cavitary lesions on imaging studies had a shorter median overall survival, with P = .02 and .0017, respectively, by the log-rank test. Abbreviation: NTM, nontuberculous mycobacteria.