Diagnostic value of T-SPOT.TB in patients with fever / 中华传染病杂志

ABSTRACT

Objective To investigate the diagnostic value of T-SPOT.TB in patients with fever.Methods T-SPOT.TB was carried out in 456 febrile patients who had no determined reason for fever or who could not be excluded from infection with Mycobacterium tuberculosis.These patients were followed up for their final clinical diagnosis and the diagnostic value of T-SPOT.TB was evaluated using the receiver operating characteristic (ROC) curve.Results In the present study,85 patients were clinically diagnosed with tuberculosis (TB) (including 34 cases of pulmonary TB,24 cases of TB infection defined as T-SPOT.TB positive without TB lesion,but effective with anti-TB treatment,10 cases of tuberculous pleurisy and 17 cases of other extrapulmonary TB) and 371 patients had no definite evidence of Mycobacterium tuberculosis infection (including 42 cases of suspected TB and 329 cases of other diseases).T-SPOT.TB had a high sensitivity of 84.3％ in TB patients and a high negative predictive value of 94.2 ％,but the specificity was 68.1％ and the positive predictive value was 41.4 ％.The Kappa value was 0.380 and the area under ROC curve was 0.762 (95％CI0.707-0.817).T-SPOT.TB had a higher sensitivity in extrapulmonary TB than in pulmonary TB (88.2 ％ vs 78.1 ％),with the negative predictive values of 95.3 ％ and 92.6 ％,Kappa values of 0.438 and 0.299,and the areas under ROC of 0.791 (95 ％ CI0.724-0.857) and 0.719 (95％CI0.623-0.815),respectively.Ninety-nine cases were T-SPOT.TB positive out of 329 patients diagnosed with other diseases.Conclusions T-SPOT.TB test can be used as a method for TB diagnosis in patients without obvious TB lesions.Due to its relatively high negative predictive value,T-SPOT.TB can be used to rule out infection with Mycobacterium tuberculosis.