Background: Information about the natural history of nontuberculous mycobacterial pulmonary disease (NTM-PD) is limited. The purpose of this study was to evaluate the long-term natural history of non-cavitary nodular bronchiectatic NTM-PD and the factors associated with treatment initiation and the frequency of spontaneous sputum culture conversion after diagnosis of NTM-PD. Methods: We evaluated 1,021 patients with newly diagnosed non-cavitary nodular bronchiectatic NTM-PD caused by Mycobacterium avium complex or M. abscessus between 2003 and 2013. Results: Of 1,021 patients, 562 (55%) initiated antibiotic treatment and 459 (45%) did not. Young age (adjusted hazard ratio [aHR] = 0.99; 95% confidence interval [CI] = 0.98–0.99), low body mass index (aHR = 0.96; 95% CI = 0.93–0.99), previous history of tuberculosis (aHR = 1.23; 95% CI = 1.01–1.50), respiratory complaints such as cough (aHR = 1.36; 95% CI = 1.05–1.75) and sputum production (aHR = 1.47; 95% CI = 1.13–1.91), and high number of involved lobes on high-resolution computed tomography (aHR = 1.22; 95% CI = 1.14–1.31) were associated with treatment initiation. Of 459 patients who did not initiate treatment, 157 (34%) showed spontaneous sputum culture conversion. None of the clinical factors was associated with spontaneous conversion. After spontaneous culture conversion, 26 of 157 (17%) showed redeveloped NTM-PD caused by a species different from the original species. Conclusions: The natural history of non-cavitary nodular bronchiectatic NTM-PD is variable. After diagnosis, the decision to initiate antibiotic therapy should be individualized based on consideration of the risk factors for disease progression. However, for patients who do not start antibiotic therapy, continuous and lifetime follow-up is recommended to manage underlying bronchiectasis and the possibility of late progression of NTM-PD.
Bibliographical noteFunding Information:
This research was supported by the National Research Foundation of Korea (NRF) founded by the Korea government (MSIT) ( NRF-2018R1A2A1A05018309 ). The sponsor had no role in the design of the study, the collection and analysis of the data, or the preparation of the manuscript.
Dr. Charles L. Daley has received grants from Insmed, Inc. and served on Advisory Boards for Insmed Inc., Johnson and Johnson, Spero, and Horizon, not associated with the submitted work. Dr. Won-Jung Koh has received a consultation fee from Insmed Inc. for the Insmed Advisory Board Meeting, not associated with the submitted work. Otherwise, we have no conflicts of interest to declare.This research was supported by the National Research Foundation of Korea (NRF) founded by the Korea government (MSIT) (NRF-2018R1A2A1A05018309). The sponsor had no role in the design of the study, the collection and analysis of the data, or the preparation of the manuscript.
© 2019 Elsevier Ltd
All Science Journal Classification (ASJC) codes
- Pulmonary and Respiratory Medicine