Background：Interferon-gamma release assay （IGRA） has been used in latent tuberculosis （TB） infection and TB diagnosis,but the results from different high TB-endemic countries are different.The aim of this study w...Background：Interferon-gamma release assay （IGRA） has been used in latent tuberculosis （TB） infection and TB diagnosis,but the results from different high TB-endemic countries are different.The aim of this study was to investigate the value of IGRA in the diagnosis of active pulmonary TB （PTB） in China.Methods：We conducted a large-scale retrospective multicenter investigation to further evaluate the role of IGRA in the diagnosis of active PTB in high TB-epidemic populations and the factors affecting the performance of the assay.All patients who underwent valid T-SPOT.TB assays from December 2012 to November 2015 in six large-scale specialized TB hospitals in China and met the study criteria were retrospectively evaluated.Patients were divided into three groups：Group 1,sputum culture-positive PTB patients,confirmed by positive Mycobacterium tuberculosis sputum culture;Group 2,sputum culture-negative PTB patients;and Group 3,non-TB respiratory diseases.The medical records of all patients were collected.Chi-square tests and Fisher＇s exact test were used to compare categorical data.Multivariable logistic analyses were performed to evaluate the relationship between the results of T-SPOT in TB patients and other factors.Results：A total of 3082 patients for whom complete information was available were included in the investigation,including 905 sputum culture-positive PTB cases,914 sputum cultmre-negative PTB cases,and 1263 non-TB respiratory disease cases.The positive rate of T-SPOT.TB was 93.3% in the culture-positive PTB group and 86.1% in the culture-negative PTB group.In the non-PTB group,the positive rate of T-SPOT.TB was 43.6%.The positive rate of T-SPOT.TB in the culture-positive PTB group was significantly higher than that in the culture-negative PTB group （x2 =25.118,P 〈 0.01）,which in turn was significantly higher than that in the non-TB group （x2 =566.l 16,P 〈 0.01）.The overall results were as follows：sensitivity,89.7%;specificity,56.37%;positive predictive value,74.75%;negative predictive value,79.11%;and accuracy,76.02%.Conclusions：High false-positive rates of T-SPOT.TB assays in the non-TB group limit the usefulness as a single test to diagnose active TB in China.We highly recommend that IGRAs not be used for the diagnosis of active TB in high-burden TB settings.展开更多
文摘Background：Interferon-gamma release assay （IGRA） has been used in latent tuberculosis （TB） infection and TB diagnosis,but the results from different high TB-endemic countries are different.The aim of this study was to investigate the value of IGRA in the diagnosis of active pulmonary TB （PTB） in China.Methods：We conducted a large-scale retrospective multicenter investigation to further evaluate the role of IGRA in the diagnosis of active PTB in high TB-epidemic populations and the factors affecting the performance of the assay.All patients who underwent valid T-SPOT.TB assays from December 2012 to November 2015 in six large-scale specialized TB hospitals in China and met the study criteria were retrospectively evaluated.Patients were divided into three groups：Group 1,sputum culture-positive PTB patients,confirmed by positive Mycobacterium tuberculosis sputum culture;Group 2,sputum culture-negative PTB patients;and Group 3,non-TB respiratory diseases.The medical records of all patients were collected.Chi-square tests and Fisher＇s exact test were used to compare categorical data.Multivariable logistic analyses were performed to evaluate the relationship between the results of T-SPOT in TB patients and other factors.Results：A total of 3082 patients for whom complete information was available were included in the investigation,including 905 sputum culture-positive PTB cases,914 sputum cultmre-negative PTB cases,and 1263 non-TB respiratory disease cases.The positive rate of T-SPOT.TB was 93.3% in the culture-positive PTB group and 86.1% in the culture-negative PTB group.In the non-PTB group,the positive rate of T-SPOT.TB was 43.6%.The positive rate of T-SPOT.TB in the culture-positive PTB group was significantly higher than that in the culture-negative PTB group （x2 =25.118,P 〈 0.01）,which in turn was significantly higher than that in the non-TB group （x2 =566.l 16,P 〈 0.01）.The overall results were as follows：sensitivity,89.7%;specificity,56.37%;positive predictive value,74.75%;negative predictive value,79.11%;and accuracy,76.02%.Conclusions：High false-positive rates of T-SPOT.TB assays in the non-TB group limit the usefulness as a single test to diagnose active TB in China.We highly recommend that IGRAs not be used for the diagnosis of active TB in high-burden TB settings.
