ABSTRACT
@#Abstract: Objective To investigate the diagnostic efficacy of rifampin-resistant real-time fluorescent quantitative nucleic acid amplification detection technology (GeneXpert MTB/RIF) in bronchoalveolar lavage fluid (BALF) combined with peripheral blood tuberculosis infection T cell spot test (T-SPOT) and tuberculosis antibody (TB-Ab) in smear-negative pulmonary tuberculosis. Methods The clinical data of 114 cases of clinically diagnosed smear-negative pulmonary tuberculosis, 80 cases of non-tuberculous pulmonary diseases and 22 cases of smear-positive pulmonary tuberculosis in our hospital from January 2019 to January 2021 were retrospectively analyzed. The detection results of peripheral blood T-SPOT, TB-Ab and BALF GeneXpert in the three groups were analyzed. The sensitivity, specificity, negative predictive value, positive predictive value, false negative rate, false positive rate and Youden index of the three detection methods were compared. The differences in the positive detection rate of smear-negative pulmonary tuberculosis between the separate detection and the combined detection of the three methods were compared. The receiver operating characteristic curve (ROC) was performed to calculate the area under the curve (AUC). Results The sensitivity of BALF GeneXpert and peripheral blood T-SPOT and TB-Ab was 66.91%, 80.88% and 90.44%, respectively. The specificity was 98.75%, 73.75% and 41.25%, respectively; the diagnostic coincidence rates were 78.70%, 78.24% and 72.22%, respectively, which were higher than 70.00%. In the smear-negative pulmonary tuberculosis group, the positive detection rates of these three methods in the smear-negative pulmonary tuberculosis group were 63.15%, 79.82% and 90.35%, respectively, and the differences were statistically significant compared with those in the non-tuberculosis pulmonary disease group (all P<0.01). The positive detection rate of the three combined methods in the smear-negative pulmonary tuberculosis group was 96.49 %, which was significantly higher than that of TB-GeneXpert method and T-SPOT, and the differences were statistically significant (χ2=37.283, P<0.01; χ2=13.612, P<0.01); the Youden index of combined detection was significantly higher than that of single detection, and the AUC of combined detection was 0.977, which was significantly higher than that of single detection. Conclusion BALF GeneXpert combined with peripheral blood T-SPOT and TB-Ab can significantly improve the diagnostic rate of bacterial-negative pulmonary tuberculosis, providing a strong basis for guiding clinical treatment.