Utility of Immunological Tests for the Diagnosis of Active Pulmonary Tuberculosis
Abstract
Objectives. To evaluate the diagnostic capabilities of the blast transformation test, phagocityc test (cellular immunity tests) and IFN-ɣ release assay (humoral immunity test) in the diagnosis of active pulmonary tuberculosis, as compared to the bacterioscopic BAAR test.
Materials and methods. 50 patients were recruited from the Cluj-Napoca Pneumophtisiology Clinic. We ran an analytical, cross-sectional, case-control, phase II study.
Results. The phagocytic activity is higher in BK-positive and RX-positive subjects, compared to controls. The time variation of the phagocytic activity in univariate analysis, is linear - positive and statistically significant. In multivariate analysis it is statistically significant only for the BK-positive subjects. Furthermore, the logistic regression analysis showed no statistical significance for the phagocytic test in the diagnosis of active pulmonary TB. The blast transformation test demonstrated a higher response in BK positive subjects, but no statistical difference between the BK, Rx or Cx positive patients. In logistic regression analysis, the blast transformation test was not statistically significant for the diagnosis of active pulmonary TB. The statistical measures of the performance of the QTB-G test, compared to the standard test in the diagnosis of active pulonary TB, were below the threshold of statistical significance. The diagnostic power of the QTB-G test is limited for the diagnosis of active TB disease.
Conclusions. The statistical value of the new investigated tests is inferior to the bacterioscopic BAAR test and can not be recommanded for clinical use.