Abstract: Objective To discuss the application value of the "Trinity Method", which combines spiral computed tomography (CT) plain scan, T cell spot detection of tuberculosis infection (T-SPOT.TB) and rifampicin resistance real-time fluorescence quantitative nucleic acid amplification (GeneXpert MTB/RIF), in the diagnosis of atypical renal tuberculosis.  
Methods In total, 75 patients with atypical renal tuberculosis diagnosed by Mycobacterium tuberculosis culture or postoperative pathological diagnosis and treated in the Department of Urology, Hebei Chest Hospital were enrolled as the tuberculosis group, and another 75 patients with non-tuberculous nephropathy were enrolled as the control group. The sensitivity, specificity, accuracy and area under curve (AUC) of different detection methods in the diagnosis of atypical renal tuberculosis were compared, with the final clinical diagnosis as the gold standard. 
Results ① The sensitivity of CT, T-SPOT.TB, CT combined with T-SPOT.TB, and GeneXpert MTB/RIF was higher than that of Mycobacterium tuberculosis culture (84.00%, 100.00%, 84.00%, 62.67%, 9.33%, respectively). The sensitivity of CT combined with T-SPOT.TB was lower than that of T-SPOT.TB (84.00%, 100.00%), but there was no significant difference compared with CT (84.00%, 84.00%). ②The specificity of CT and T-SPOT.TB was lower than that of Mycobacterium tuberculosis culture (85.33%, 74.67%, 100.00%). There was no significant difference in the specificity of CT combined with T-SPOT.TB, GeneXpert MTB/RIF and Mycobacterium tuberculosis culture (97.33%, 100.00%, 100.00%). The specificity of CT combined with T-SPOT.TB was higher than that of each indicator alone (97.33%, 85.33%, 74.67%).③The accuracy of CT, T-SPOT.TB, CT combined with T-SPOT.TB and GeneXpert MTB/RIF was higher than that of Mycobacterium tuberculosis culture (84.67%, 87.33%, 90.67%, 81.33%, 54.67%, respectively). The accuracy of CT combined with T-SPOT.TB was higher than that of each indicator alone (90.67%, 84.67%, 87.33%). ④The AUC of CT, T-SPOT.TB, CT combined with T-SPOT.TB, GeneXpert MTB/RIF was higher than that of Mycobacterium tuberculosis culture (AUC=0.847, 0.873, 0.907, 0.813, 0.547). The AUC of CT combined with T-SPOT.TB was higher than that of each indicator alone (AUC=0.907, 0.847, 0.873). 
Conclusion Spiral CT plain scan combined with T-SPOT TB and GeneXpert MTB/RIF can improve the clinical detection rate and pathogenic diagnostic efficacy of atypical renal tuberculosis. It is recommended to use the "Trinity Method" in clinical diagnosis of atypical renal tuberculosis. 

Key words: tuberculosis, renal, tomography, spiral computed, Mycobacterium tuberculosis