ABSTRACT
Objective To explore the efficacy of T-cell spot test of tuberculosis infection(T-SPOT.TB)in the differential diagnosis of spinal tuberculosis(STB),and optimize diagnostic efficacy through the optimal cut-off value of receiver operating characteristic(ROC)curve.Methods Clinical data of patients with spinal infection in a hospi-tal from January 2010 to May 2019 were collected,including preoperative T-SPOT.TB test results,white blood cell count,C-reactive protein,erythrocyte sedimentation rate,procalcitonin,and tuberculosis antibodies,etal.Clinical diagnosis was conducted based on diagnostic criteria.The sensitivity and specificity of T-SPOT.TB in preoperative diagnosis of STB and other spinal infection was analyzed,and the diagnostic efficacy of the optimized T-SPOT.TB indicators was evaluated.Results A total of 132 patients were included in this study,out of whom 78 patients(59.09％)were diagnosed with STB,and 54(40.91％)were diagnosed with non-tuberculosis(non-TB)spinal in-fection.The sensitivity and specificity of T-SPOT.TB in differential diagnosis of STB were 67.68％and 66.67％,respectively.Univariate logistic regression analysis showed that compared with non-TB spinal infection,the OR va-lue of T-SPOT.TB test in diagnosing STB was 4.188(95％CI:1.847-9.974,P＜0.001).The optimized T-SPOT.TB evaluation index through ROC curve to determine the optimal cut-off values of ESAT-6,CFP-10,and CFP-10+ESAT-6 for differential diagnosis of STB and non-TB spinal infection were 12.5,19.5,and 36,respec-tively,and area under curve(AUC)values were 0.765 6,0.741 5,and 0.778 6,respectively,all with good diag-nostic efficacy.CFP-10+ESAT-6 had the highest AUC.CFP-10+ESAT-6 specific spot count had higher efficacy in the diagnosis of STB,with a diagnostic accuracy of 75.56％,higher than 67.42％of pre-optimized T-SPOT.TB.Conclusion T-SPOT.TB test has high diagnostic efficacy in differentiating STB from non-TB spinal infection.Posi-tivity in T-SPOT.TB test,especially with spot count of CFP-10+ESAT-6 over 36,indicates a higher likelihood of STB.