Significance of T-SPOT.TB and peripheral platelet count and PLR in differential diagnosis of active pulmonary tuberculosis and inactive pulmonary tuberculosis

  Objective  To investigate the significance of T cell spot test of tuberculosis infection (T-SPOT.TB) and peripheral platelet count (PLT) and platelet-lymphocyte ratio (PLR) in the differential diagnosis of active pulmonary tuberculosis (TB) and inactive pulmonary TB.

  Methods  A retrospectively analysis was conducted for 250 clinical cases of suspected pulmonary TB, including 115 active pulmonary TB cases, 63 inactive TB cases and 72 non-TB pneumonia cases, in Yichun People's Hospital from January 2019 to June 2021. The laboratory detection results, such as T lymphocyte spot test for TB, PLT, PLR, bacterial acid-antacid staining, and final diagnosis of the cases were collected for statistical analysis.

  Results  The positive rate of T-SPOT.TB in the non-TB pneumonia patients (4.17%) was significantly lower than those in the inactive pulmonary TB patients (82.54%) and active pulmonary TB patients (85.22%), the platelet count and PLR in the active pulmonary TB patients were significantly higher than those in the inactive pulmonary TB patients and the non-TB pneumonia patients. The multivariate logistic regression analysis showed that the sensitivity and specificity of T-SPOT.TB combined with PLT and PLR in the diagnosis of active pulmonary TB were 63.30%, and 86.50%.

  Conclusion  T-SPOT. TB combined with PLT and PLR is helpful in the differential diagnosis of active pulmonary TB and inactive pulmonary TB, and can provide evidence for clinical anti-TB therapy.