ABSTRACT
Objective To evaluate the clinical application value of fluorescence PCR melting curve method in the drug-resistance detection of Mycobacterium tuberculosis.Methods With the Lowenstein-Jensen culture method and the absolute concentration method as the comparison,the fluorescent PCR melting curve method was used to detect the resistance to rifampin and isoniazid in 53 cases of pulmonary tuberculosis(TB)respectively.Results The single drug resistance rates and multidrug resistance (MDR) rate detected by the two methods had no significant statistical difference(P >0.05).The comparison between the two methods for detecting the same sample showed that compared with the absolute concentration method,the sensitivity and specificity of the melt-ing curve method for detecting rifampin-resistance,isoniazid-resistance were 80.0% and 81.0%,100.0% and 93.8% respectively, the accuracies were 92.2% and 86.8% respectively,the Kappa values in the consistency analysis of the two methods were 0.754 and 0.710 respectively,indicating the good consistency between them.Conclusion Compared with the traditional methods,the melting curve method has good sensitivity and good specificity with safety,high efficiency and good application value in the treat-ment of drug-resistant pulmonary TB.
ABSTRACT
Objective To establish a diagnostic model of multiple cytokines for differential diagnosis of tuberculous pleural effusion , and compare its diagnostic accuracy with tuberculosis infected T cells detection ( T-SPOT.TB ) in order to evaluate its diagnostic performance.Methods Case-control study.Totally 147 patients with pleural fluid in Tianjin Haihe Hospital were enrolled and categorized as tuberculous pleural effusion group ( n=95 ) and malignant pleural effusion group ( n=52 ) from December 2011 to June 2013.Pleural effusion cytokines including interferon-γ( IFN-γ) , C-X-C motif chemokine 10 (CXCL-10), tumor necrosis factor-α(TNF-α), vascular endothelial growth factor (VEGF), IL-2, IL-16, IL-17, IL-27 and IL-33 were tested by liquid chip technology and analyzed by Binary Logistic regression and receiver operating characteristic curve (ROC), and the pleural effusion was also detected by tuberculosis infected T cells detection ( T-SPOT.TB) as a control.Results The comparison of the AUC of cytokines is:CXCL-10>IL-27>IFN-γ>IL-33 >IL-17>IL-16>TNF-α>VEGF>IL-2; After that, CXCL-10, IFN-γ, IL-27 and IL-33 were included the Binary Logistic regression model.The regression equation is P=1/1+e-( -16.851+0.390 ×IFN-γ+0.006 ×IL-27+0.020 ×IL-33).The AUC, sensitivity and specificity of the diagnostic model were 99.5%, 96.84%, and 98.08%, respectively.Both AUC and sensitivity of the diagnostic model were superior to those of any single index.Compared with T-SPOT.TB (0.995 ±0.003), the AUC of the diagnostic model (0.921 ±0.023) was significantly greater ( Z=3.235, P 0.05).The Kappa of the two methods was 0.795, which meant fine agreement of the evaluations of the two raters.Conclusion The application of liquid array technology of high sensitivity and repeatability with high throughput provided a novel insight and method in the clinical diagnosis , treatment and prevention for tuberculous pleural effusion scientifically and accurately.