Utility of Real-Time Quantitative Polymerase Chain Reaction in Detecting Mycobacterium tuberculosis.

Zhongquan Lv,Mingxin Zhang,Xinxin Lu,Hui Zhang

doi:10.1155/2017/1058579

Abstract

This study aimed to assess the value of real-time quantitative polymerase chain reaction (RT-qPCR) for the detection of Mycobacterium tuberculosis (MTB). Samples from 192 patients with suspected MTB were examined by RT-qPCR and an improved Löwenstein–Jensen (L-J) culture method. To evaluate the diagnostic usefulness of RT-qPCR in detecting MTB, a receiver operating characteristic (ROC) curve for RT-qPCR was generated, and the area under the curve (AUC) as well as a cutoff value was calculated. Using the L-J culture method as the gold standard, accuracy of the RT-qPCR method for detecting MTB was 92.7%, with sensitivity and specificity of 62.5% and 97.02%, respectively. In comparison with the improved L-J culture method, the AUC of RT-qPCR ROC curve was 0.957, which was statistically significant (p < 0.001). The Youden Index reached the maximum value (0.88) for gene copy number of 794.5 IU/mL, which was used as the cutoff value. RT-qPCR detection of MTB yielded results consistent with those of the improved L-J culture method, with high accuracy. RT-qPCR may be used as an auxiliary method for etiological diagnosis of tuberculosis.

Highlights

Tuberculosis is an infectious disease which is seriously harmful to human health and is one of the major public health concerns worldwide
Detection of Mycobacterium tuberculosis (MTB) was performed in 192 samples using both real-time quantitative polymerase chain reaction (RT-qPCR) and the improved L-J culture method
Among the 192 samples, 15 cases were positive for MTB based on results in both methods; 5 cases were positive based on the improved L-J culture method but negative based on RT-qPCR results; 9 cases were negative based on the improved L-J culture method but positive based on RT-qPCR results, and 163 cases were negative based on both methods (Table 1)

Summary

Introduction

Tuberculosis is an infectious disease which is seriously harmful to human health and is one of the major public health concerns worldwide. According to the report of World Health Organization (WHO) in 2013, nearly 8.6 million of new cases of tuberculosis were reported in the world in 2012, with an incidence rate of about 122/100,000 and 1.3 million total deaths [1]. China is one of the 22 countries with a high burden of tuberculosis, accounting for 15% of the total global burden [2]. Tuberculosis prevalence in China is second only to that of India. Annual incidence of tuberculosis in China is estimated at 0.9–1.1 million, accounting for 12% of global incidence [1]. China is one of the 27 countries with high prevalence of multidrug resistant tuberculosis. 50% of global drug resistant tuberculosis cases are found in China and India [3]

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