Abstract
Objective: The aim of this study was to distinguish and compare the chest imaging features of non-tuberculous mycobacteria lung disease (NTM-LD) and pulmonary tuberculosis (PTB) in patients with sputum AFB-smear positive as an earlier differential diagnosis between these two is very important in clinical practice.
Methods: A total of 4167 previously untreated cases with AFB smear-positive sputum were collected from Jan 2011 to Jan 2014, in our hospital, Among them, 124 cases were identified with NTM-LD after specimen culture and strain identification. A cohort of 210 patients with PTB was randomly selected from the remaining 4043 cases with PTB as comparator. The clinical and chest computed tomography (CT) imaging data were compared.
Results: The most prevalent pathogens in patients with NTM-LD were Mycobacterium abscessus(42%, 52/124). Univariate analysis showed patients with NTM-LD more frequently had bronchiectasis (85.5% vs. 45.7%, p<0.001), thin-walled cavity(D ≥3cm)(16.9% vs. 7.6%, p=0.011)compared to PTB patients. The right middle lobe (23.9% vs. 16.3%, p<0.001) and left lingual segment bronchiectasis (19.9% vs 8.2%, p<0.001) were more prominent in NTM-LD. Multivariate analysis showed, bronchiectasis (OR=8.521, 95%CI: 4.209-17.250, p <0.001)and thin-walled cavity (D ≥3cm)(OR=3.561, 95%CI:1.394-9.097, p=0.008, )were also the independent predictors for the diagnosis of NTM-LD.
Conclusions: Bronchiectasis and thin-walled cavity (D ≥3cm)are the frequently the chest CT features in patients with NTM-LD, which might be helpful for an early diagnosis in patients with AFB-smear positive.
- Copyright ©ERS 2015
