The diagnosis values of whole blood IFN-γrelease assay on pulmonary tuberculosis and extra-pulmonary tuberculosis / 预防医学

ABSTRACT

Objective To evaluate the diagnosis values of whole blood IFN-γ release assay on pulmonary tuberculosis ( TB)and extra-pulmonary tuberculosis. Methods One hundred and eighty five patients with tuberculosis( including 119 pulmonary TB and 66 extra-pulmonary TB),139 patients with other respiratory diseases and 100 healthy people were enrolled. Mycobacterium tuberculosis infection testing was conducted with methods of IFN -γ release assay,sputum bacterial culture and sputum smear,respectively. Results of pathogen culture and/or clinical diagnosis were used as the golden standard to evaluate the sensitivity and specificity of these three methods. Results Compared with the results of clinical diagnosis,the sensitivity and specificity of IFN-γ release assays was 93. 51% and 84. 52%,respectively. There was no significant difference in sensitivity between pulmonary diagnosis( 90. 76%) and extra - pulmonary diagnosis (98. 49%)(P>0. 05). The sensitivity of sputum smear was 11. 76% in patients with pulmonary and 3. 03% in patients with extra - pulmonary. And the sensitivity of sputum bacterial culture in these two patient groups was 24. 37% and 3. 03%,respectively. Sensitivity of the IFN-γ release assay was higher than that of sputum culture and sputum smear (P<0. 05). The results of pathogen culture showed that 33 of 424 samples were positive,in which 2 were mycobacterium abscessus positive and 31 were mycobacterium tuberculosis positive. Compared with the results of pathogen culture,the sensitivity of IFN-γrelease assay was 90. 32%(95%CI75. 10% -96. 65%). Conclusion IFN-γrelease assay is a fast,sensitive and convenient method to detect pulmonary and extra pulmonary tuberculosis. It is worthy to be applied to clinical practice.