Diagnostic value of urinary routine, renal function, tuberculosis antibody test, and t-cell spot tests for tuberculosis infection in urinary tuberculosis

Abstract

Background To examine the clinical utility of urinary routine and renal function、Tuberculosis antibody test (TB-DOT) or T-cell spot tests for TB infection(T-SPOT.TB) in blood, either separately or in combination, for the diagnosis of urinary tuberculosis (UTB). Methods Retrospective analysis of urinary routine, renal function, TB-DOT, and T-SPOT.TB - alone and/or in combination - for the diagnosis of UTB in 95 suspected patients from January 2020 to December 2022 in our institution. Results Patients in the UTB group had statistically different white blood cells (WBC), red blood cells (RBC), creatinine (Crea), TB-DOT, and T-SPOT.TB levels or positivity rates compared to those in the non-UTB group (P < 0.05). For individual assays, T-SPOT.TB had the highest specificity and PPV (100.0%, 100.0%); WBC had the highest AUC (0.847) and was significantly higher than Urea (P < 0.05); TB-DOT and RBC had relatively good sensitivity (85.7%, 88.9%). In addition, WBC correlated with both TB-DOT (r = 0.251, P > 0.05) and T-SPOT.TB (r = 0.270, P < 0.05). In the parallel combined WBC, Crea, TB-DOT, and T-SPOT.TB assay, the sensitivity of WBC + TB-DOT + T-SPOT.TB (93.1%) was superior to WBC + TB-DOT (90.3%) and the NPV (87.5%) was higher than WBC + T-SPOT.TB (81.0%), both of which were superior to WBC + Crea + TB-DOT + T-SPOT.TB (35.1%, 40.0%), and its AUC (0.930) were the largest. Conclusion In the early identification of UTB, the sensitivity of T-SPOT.TB or TB-DOT tests are higher than that urine routine and renal function tests. The parallel combination of WBC, TB-DOT, and T-SPOT.TB has better diagnostic efficacy for UTB, which is beneficial for rapid clinical diagnosis of UTB.