Abstract:

Objective To discuss the difference in CT manifestations of Mycobacteria intracellulare lung di-sease and pulmonary tuberculosis both with cavitation.Methods Twenty-six cases of Mycobacteria intracellulare lung disease(Observation group) and 40 cases of pulmonary tuberculosis (Control group) accompanied by a cavitation of above 10 mm were studied. Forty patients with pulmonary tuberculosis included in the study were chosen randomly from 862 cases of secondary pulmonary tuberculosis, which were diagnosed with clinical examinations and lab tests in the Chongqing Public Health Medical Center from June 2016 to March 2018. The cases all had complete clinical and imaging data before treatment, and did not receive anti-NTM and tuberculosis treatments. Cases combined with pneumoconiosis, diabetes, HIV or other infections were excluded. Statistical analysis was conducted on CT findings of the two groups, including classification and distribution of bronchiectasis, cavitation morphology and neighboring pleural thickening, lung volume reduction,emphysema and mediastinal lymph node enlargement.Results In the observation group, bronchiectasis (92.3%, 24/26) including varicose bronchiectasis and cystic bronchiectasis (88.5%, 23/26), calcification of lung lesions (57.7%, 15/26), lung volume reduction (69.2%, 18/26), emphysema (57.7%, 15/26), thin-walled cavities (73.1%, 19/26), and pleural thickening adjacent to the cavities (80.8%, 21/26) were all more than those in the control group (60.0% (24/40), 35.0% (14/40), 15.0% (6/40), 15.0% (6/40), 10.0% (4/40), 25.0% (10/40) and 37.5% (15/40)), which were statistically significant (χ ²=8.29, 18.28, 13.24, 20.03, 17.48, 14.79 and 11.90 respectively, P<0.05); in the observation group, large nodules (diameter ≥10 mm) 19.2% (5/26), infiltrates around the nodules (34.6%, 9/26), single cavities (7.7%, 2/26), thick-walled cavities (26.9%, 7/26), mediastinal lymph node enlargement (23.1%, 6/26) and pericardial effusion (7.7%, 2/26) were all significantly lower than those in the control group (57.5% (23/40), 72.5% (29/40), 37.5% (15/40), 75.0% (30/40), 47.5% (19/40), and 30.0% (12/40)) (χ ²=9.45,9.26,7.32,14.79,3.99 and 4.69 respectively, P<0.05). In the observation group, the incidences of 0-lobe and 1-2-lobe bronchiectasis 11.5% (3/26) and 19.2% (5/26) respectively were lower than those in the control group 40.0% (16/40) and 50.0% (20/40) respectively, the differences were statistically significant (χ ²=6.23 and 6.34, P<0.05); the incidence of 3-4-lobe and ≥5-lobe bronchiectasis 30.8% (8/26) and 38.5% (10/26) respectively were higher than those in the control group (5.0% (2/40) and 5.0% (2/40) respectively), the differences were statistically significant (continuity correction χ ²=6.26 and 9.72, respectively, P<0.05); In the observation group, the incidence of 3-4-lobe bronchiectasis which were varicose and cystic types 26.9% (7/26) was higher than those in the control group 5.0% (2/40) (continuity correction, χ ²=4.70, P<0.05). Conclusion The thin-walled cavities, lung volume reduction, emphysema, extensive varicose bronchiectasis and cystic bronchiectasis of Mycobacteria intracellulare lung disease with cavitation are all more than pulmonary tuberculosis, large nodules (diameter ≥10 mm), infiltrates around the nodules, single cavities, thick-walled cavities, mediastinal lymph node enlargement and pericardial effusion are all significantly lower than pulmonary tuberculosis in the CT manifestations, which is helpful for differentiation between the two groups.

Key words: Mycobacterium infections, atypical, Tuberculosis, pulmonary, Tomography, X-ray, Diagnostic imaging, Comparative study computed