To explore the application of Xpert MTB/RIF in rapid diagnosis of initial drug-resistant tuberculosis

Objective To study the sensitivity and reliability of rifampicin-resistant real-time fluorescence quantitative nucleic acid amplification detection technology (X pert MTB/RIF) in the rapid diagnosis of drug resistance in pulmonary tuberculosis patients, and to evaluate the role of X pert MTB/RIF in the screening of clinical trials. Methods With the method of comprehensive screening, Hebei Province Chest Hospital all early diagnosis of suspected pulmonary tuberculosis patients, a total of 356 people, taking the sputum, alveolar lavage fluid samples, sent to the hospital clinical laboratory, respectively for the colloidal gold test, sputum tuberculomyces culture+ drug susceptibility test, X-pert MTB/RIF detection.Its positive and negative crowd were detected, consistency of tuberculous culture+ drug sensitivity in testing drug resistance of rifampin and other drug resistance were compared; The sensitivity and specificity of X-pert MTB/RIF were compared using the colloidal gold test as the gold standard for bacterial species determination.The sensitivity and specificity of tuberculum culture and drug susceptibility test were compared.At the same time, X-pert MTB/RIF was used to compare sputum samples and lavage samples of patients, and to compare whether there showed any difference. Results (1)Rifampin resistant as the sensitivity of the simplified index was 100%(78/78), specificity of 99.28%(276/278), positive predictive value was 97.50%(78/80), negative predictive value was 100%(276/276). The two had good consistency (Kappa≥0.75). (2)With colloidal gold method to judge the gold standard of the mycobacterium tuberculosis, X-pert MTB/RIF detection specificity 85.71%(6/7), sensitivity was 99.71%(348/356), positive predictive value was 99.71%(348/349), negative predictive value was 85.71%(6/7). The two had good consistency (Kappa≥0.75). (3)With colloidal gold method to judge the gold standard of the mycobacterium tuberculosis, X-pert MTB/RIF detection specificity 100% (276/276), sensitivity was 97.50%(78/80), positive predictive value was 100%(78/78), negative predictive value was 99.28%(276/278). The two had good consistency (Kappa≥0.75). (4)Sputum samples and alveolar lavage samples were analyzed, and Kappa of the two groups was greater than 0.75, indicating a good consistency.(5)The detection time of X-pert MTB/RIF method was significantly shorter than that of tuberculosis culture+ drug sensitivity method (P<0.05), and the difference was statistically significant. Conclusions The X-pert MTB/RIF test, as an auxiliary means for the detection and rapid diagnosis of initial drug-resistant tuberculosis, has high sensitivity and specificity.At the same time, its detection time is short, which has obvious advantages over traditional methods. Key words: Extensively drug-resistant tuberculosis; Diagnosis; Nucleicacid amplification techniques; Rifampin