Comparison of three molecular diagnostic techniques in the detection of Mycobacterium tuberculosis in extrapulmonary tuberculosis pus samples
10.3760/cma.j.cn114452-20240607-00300
- VernacularTitle:三种分子诊断技术在常见肺外结核脓液样本中的结核分枝杆菌检测效果比较
- Author:
Zhuo WANG
1
;
Yuanwu ZOU
;
Yaping JIANG
;
Jing LI
;
Chunmei LI
;
Xiaolin WANG
Author Information
1. 陕西省结核病防治院检验科，西安 710100
- Publication Type:Journal Article
- Keywords:
Tuberculosis;
Diagnosis;
Molecular diagnostic techniques;
Skeletal tuberculosis;
Superfical tuberculous lymphadenitis;
Pus
- From:
Chinese Journal of Laboratory Medicine
2025;48(2):270-275
- CountryChina
- Language:Chinese
-
Abstract:
Objective:The performance of GeneXpert MTB/RIF (Xpert), DNA isothermal amplification fluorescence assay (DNA isothermal amplification) and RNA simultaneous amplification and testing (SAT-TB) were evaluated by detecting Mycobacterium tuberculosis in the pus samples of superficial tuberculous lymphadenitis and skeletal tuberculosis, two common extrapulmonary tuberculosis. Methods:Cross-sectional study. A total of 242 patients with suspected superficial tuberculous lymphadenitis and skeletal tuberculosis admitted to Shaanxi Provincial Tuberculosis Prevention and Control Hospital were collected from January 2022 to December 2023 and pus samples were taken from the lesions for examination. Among them, 210 patients were laboratory confirmed or clinically diagnosed with tuberculosis, 108 patients with superficial tuberculous lymphadenitis and 102 patients with skeletal tuberculosis. 32 patients without tuberculosis. Mycobacterium Tuberculosis culture, Xpert, DNA isothermal amplification, and SAT-TB detection were performed on the pus samples of all patients. The detection results were statistically analyzed using SPSS26.0 and MedCalc software. The detection effectiveness of several different detection methods for Mycobacterium tuberculosis in pus samples was compared, and P<0.05 was considered statistically significan. Results:The sensitivity of Mycobacterium Tuberculosis culture, Xpert, DNA isothermal amplification and SAT-TB in TB patients were 25.2% (53/210), 88.6% (186/210), 81.9% (172/210) and 61.0% (128/210), respectively. The area under curve (AUC) values of the four detection methods in the diagnosis of tuberculosis were 0.626, 0.943, 0.910 and 0.805, respectively. The AUC value of tuberculosis culture in the diagnosis of tuberculosis was significantly lower than that of the three molecular diagnostic techniques ( P<0.05). The AUC value of DNA isothermal amplification was significantly higher than that of SAT-TB detection method ( P<0.05). The positive tuberculosis culture was used as a reference standard where the sensitivity of Xpert, DNA isothermal amplification and SAT-TB reached 96.2%(51/53), 90.6%(48/53) and 86.8%(46/53), respectively. There was no significant difference in sensitivity among the three molecular diagnostic techniques ( P>0.05). In Xpert MTB positive patients, the positive rate of DNA isothermal amplification was 90.3% (168/186), and there was good consistency between DNA isothermal amplification and Xpert MTB detection results ( Kappa=0.765, P<0.001). Xpert detected 27 cases of rifampicin resistance, the resistance rate was 12.9% (27/210). Conclusion:GeneXpert and DNA isothermal amplification have high sensitivity and specificity in the samples of extrapulmonary tuberculosis pus, and the results of DNA isothermal amplification and GeneXpert MTB/RIF detection are highly consistent. In tuberculosis screening, DNA isothermal amplification fluorescence detection can be used for preliminary screening to reduce the detection cost.
