Abstract:

Objective To evaluate the diagnostic values of different detection methods for pulmonary tuberculosis (PTB).Methods From January to December of 2017, a total of 149 patients with PTB who were admitted to the Qingyuan Center for Chronic Disease Control, Guangdong Province were selected in the PTB group, and 96 patients with other pulmonary disease were selected in the non-PTB group. The clinical data of all study subjects were collected. The T-SPOT.TB, tuberculin skin test (TST), sputum smear microscopy, sputum culture, and GeneXpert MTB/RIF were performed. The diagnostic efficacies of these methods were evaluated comprehensively.Results 65.8% (98/149) of the patients in the PTB group had a disease course of ≥30 days, which was higher than 52.1% (50/96) of the patients in the non-PTB group. The difference was statistically significant (χ²=4.57, P=0.032). Among the tested methods, sputum etiological examinations had the best specificity. The specificities of sputum smear microscopy, sputum culture, and GeneXpert MTB/RIF were 100.0% (96/96), 100.0% (96/96), and 96.9% (93/96), respectively. As to the comparison in the sensitivity, T-SPOT.TB had the highest sensitivity of 86.6% (129/149). The rank of Youden index of each detection method, from high to low, was TST+T-SPOT.TB (0.58), GeneXpert MTB/RIF (0.54), T-SPOT.TB (0.48), sputum culture (0.38), TST (0.27), and smear smear microscopy (0.24).ConclusionThe sputum etiological examinations are still the gold standard for the diagnosis of PTB. The combination of multiple test methods can help the clinical diagnosis of smear-negative PTB.

Key words: Tuberculosis, pulmonary, Diagnosis, differential, Laboratory techniques and procedures, Evaluation studies