Diagnostic Value Of Interferon Gamma Release Assays In Children With Pulmonary Tuberculosis

Objective:To explore the value of interferon gamma release assays in the diagnosis of pulmonary tuberculosis in children.Methods: The data of suspected pulmonary tuberculosis in Children's Hospital of Chongqing Medical University from January 2017 to December2017 were retrospectively collected.According to the clinical data and grouping criteria,137 of 914 cases were pulmonary tuberculosis group,the remaining 777 cases were non-tuberculosis group,and 137 cases of pulmonary tuberculosis group were further divided into two sub-groups,including 34 cases of severe tuberculosis group and 103 cases of non-severe tuberculosis group.The sensitivity,specificity and Kappa value of IGRA were evaluated and compared with tuberculin skin test(TST)to explore the diagnostic value of IGRA.Results: The sensitivity of IGRA was 92.0%(95% CI: 87.4-96.5),higher than that of TST(P < 0.05),and the specificity of IGRA was 96.5%(95% CI: 95.2-97.9).However,there was no significant difference between IGRA and TST(P > 0.05),and the Kappa value was 0.098(P < 0.05).Thesensitivity of IGRA in 0-5 years old group,5-10 years old group and over10 years old group was higher than that of TST(P < 0.05).There was no significant difference in the number of spots in pore A and pore B in pulmonary tuberculosis group(P > 0.05).The positive rates of IGRA and TST were 91.2% and 17.6% in severe tuberculosis group and 92.2% and51.5% in non-severe tuberculosis group respectively.There was a significant difference in the positive rates of TST between the two groups(P < 0.05),but there was no significant difference in the positive rates of IGRA between the two groups(P > 0.05).Conclusion: The sensitive of IGRA in diagnosis of pulmonary tuberculosis in children is 92.0%(95%CI:87.4%-96.5%),which is higher than TST.TSPOT is beneficial to the detection of pulmonary tuberculosis patients.The specificity of IGRA is 96.5%(95.2%-97.9%).It has a certain value for excluding pulmonary tuberculosis.The results of IGRA and TST are consistent,but the consistency is poor.It can not be considered that there are differences in the number of spots in pore A and pore B in different age groups of pulmonary tuberculosis.TST is prone to false negative results in severe tuberculosis cases,while IGRA results are not affected by the severity of tuberculosis.