The clinical analysis of chronic obstructive pulmonary disease patients complicated with nontuberculous mycobacterial pulmonary disease

Abstract

Objectives: Long-term use of inhaled corticosteroids (ICS) was reported as a risk factor for patients with chronic obstructive pulmonary disease (COPD) complicated with nontuberculous mycobacterial lung disease (NTM-LD). But it was not reported often in China. Methods: We conducted a retrospective analysis of patients who were diagnosed with COPD and NTM-LD in our department from January 1(st) 2017 to December 31(th) 2018. Results: This study consisted of 10 male and 5 female patients with a mean age of (66±7) years. The detailed clinical data and radiological images were reviewed systemically. There were 4 current smokers (26.7%) and 6 past smokers (40%). All cases were current ICS users, with a mean duration of (27.3±9.7) months, ranging from 3 months to 61 months. Among them, 8 cases (53.3%) used inhaled fluticasone and 7 cases (46.7%) used inhaled budesonide. Aggravated coughing (15 cases, 100%), expectoration (15 cases, 100%) and dyspnea (10 cases, 66.7%) were the common clinical manifestations, although fever was only reported in 4 cases (26.7%). All cases showed normal white blood cell count and lymphocyte count, and some of them (7 cases, 46.7%) showed elevated erythrocyte sedimentation rate and C-reactive protein. Most of them (14 cases, 93.3%) had normal TB-SPOT results. Multiple focal bronchiectasis (9 cases, 60%) and significant emphysema (12 cases, 80%) were the common manifestations of basic high-resolution CT (HRCT) prior NTM infection. The occurrence of bronchiectasis (15 cases, 100%), "tree in bud" sign (12 cases, 80%) and tiny cavities (8 cases, 53.3%) were the common HRCT abnormalities for the NTM-LD cases. According to the 2007's NTM-LD diagnosis criteria, most of them (13 cases, 86.7%) were diagnosed with positive sputum samples at least twice, and 2 cases were diagnosed with positive CT-directed bronchial alveolar lavage fluid. NTM-PCR analysis was performed routinely for the isolated NTM samples to identify the NTM species. Mycobacterium avium complex (MAC) was the most common NTM species (8 cases, 53.3%). After treatment with proposed anti-NTM strategies, most cases improved (9 cases, 60%), and some of them (4 cases, 26.7%) were cured and a few cases (2 cases, 13.3%) relapsed. Conclusions: When COPD patients treated with ICS showed aggravated cough, expectation and/or dyspnea, and new occurrence of bronchiectasis and/or "tree in bud" sign in the recent HRCT, the differential diagnosis of NTM-LD should be considered. Respiratory samples should be arranged for NTM cultures and PCR analysis as soon as possible. Earlier antimicrobial strategies according to the identified NTM species would improve the clinical outcomes.