A Comparative Study On Clinical And Hrct Signs Between Non-tuberculous Mycobacteria Lung Disease And Pulmonary Tuberculosis In Non-immunocompromised Patients

Objective: To explore clinical factors and HRCT signs which could be useful for the diagnosis and differential diagnosis of non-tuberculous mycobacteria lung disease(NTM-LD)and pulmonary tuberculosis(PTB)in non-immunocompromised patients through a retrospective analysis,thus assisting in selecting appropriate clinical treatments.Study subjects and method: The clinical and imaging data of 74 cases with NTM-LD and 108 cases with PTB in non-immunocompromised patients,who were clinically confirmed with specimen culture and strain identification from January2013 to December 2015,were retrospectively collected.Two physicians with rich diagnostic experience on chest imaging were responsible for analyzing chest CT imaging.The general data and pulmonary HRCT signs in both groups,including age,sex,distribution,density,pulmonary atelectasis,nodule,cavity,tracheal and bronchial wall thickening,bronchiectasia,“tree-in-bud”,mediastinal/hilar lymphadenectasis,pleural/pericardial effusion,pleural thickening and other related factors,were retrospectively analyzed and compared.Comparison of general clinical conditions between two groups was done with independent sample t-test and ?2 test.Each imaging sign was compared between two groups using ?2 test.Variables with statistical significance in single factor analysis should be further analyzed with logistic regression to ascertain the ones with the most value for differential diagnosis.Results: In NTM-LD group,the male and female ratio was 1:1.6,with a mean age of(58.45±11.18)years;while in PTB group,the male and female ratio was 1.8:1,with a mean age of(44.13±19.45)years.The difference in age of onset and sex ratio were both statistically significant(P<0.05).Age of onset,sex,lesion distribution,nodule size,cavity distribution,thickness of the walls and size of cavity,tracheal and bronchial wall thickening,number,extent and background of bronchiectasia,mediastinal/hilar lymphadenectasis,pleural/pericardial effusion and pleural thickening were different in the two groups(P<0.05).Bronchiectasia without pulmonary consolidation was more frequently predicting for the diagnosis of NTM(?>0),while low age of onset,large nodule,purely non-subpleural cavity and mediastinal/hilar lymphadenectasis were more frequently predicting for the diagnosis of PTB,and purely non-subpleural cavity was the most significant HRCT differential sign between the two groups(?=-12.038,OR value=0.000)and diagnostic accuracy could be increased from 59.3% to 98.4% according to the above five factors.Conclusion: NTM-PD in non-immunocompromised host more often occurs in the elderly and female patients,while PTB is more commonly seen in the young and middle-aged and male patients.The application of chest HRCT is rather helpful for the early diagnosis and differential diagnosis of the two diseases.HRCT signs of cavity distribution,background of bronchiectasia,nodule size,mediastinal/hilar lymphadenectasis and purely non-subpleural cavity were significant for differential diagnosis of the two diseases and purely non-subpleural cavity was the most important one.