The Diagnostic Value Of T-SPOT.TB In Suspected Pulmonary Tuberculosis Patients With High Risk Factors And The Influencing Factors Of Its Diagnostic Accuracy

Objective:To investigate the influencing factors of false-positive and false-negative T-SPOT.TB for tuberculosis infection and its auxiliary diagnostic value in suspected pulmonary tuberculosis cases with high risk factors.Methods:Retrospective analysing clinical data,clinical diagnosis results and T-SPOT.TB examination results of 454 adult hospitalized patients suspected tuberculosis in our hospital from October 2017 to October 2020.Patients meeting any of the criteria [age≥65years old,diabetic patients and immunodeficiency patients(AIDS,autoimmune/rheumatic diseases,primary immunodeficiency patients or patients receiving immunosuppressive therapy)] are assigned to the high-risk group.Comparison of the auxiliary diagnostic value of T-SPOT.TB in high-risk group and non-high-risk group,and used Logistic regression method to analyze the influencing factors of false negative and false positive results.Results:The sensitivity of T-SPOT.TB in the high-risk group and the non-high-risk group of pulmonary tuberculosis was 76.34% and 90.00%,the specificity was 76.35% and82.93%,and the accuracy was 76.35% and 85.92%,respectively.There were statistically significant differences in sensitivity and accuracy between the groups(P=0.014;P=0.010),but no significant differences in specificity between the two groups(P=0.183).Logistic regression analysis show the risk factor for false-negative results of T-SPOT.TB was age ≥65 years(OR=2.624,P=0.019),and the risk factors for false-positive results of T-SPOT.TB included gender(male)(OR=3.533,P=0.001)and combined malignant tumors(OR=4.410,P<0.001).Conclusion:T-SPOT.TB has a high value in auxiliary diagnosis of tuberculosis,especially in the non-high-risk group,the auxiliary diagnostic value is higher.The false-negative and false-positive risk factors of T-SPOT.TB should be considered in clinical application of it as an adjunctive test for the diagnosis of tuberculosis patients.