Feasibility and Performance of Loop-Mediated Isothermal Amplification Assay in the Diagnosis of Pulmonary Tuberculosis in Decentralized Settings in Eastern China.

Zhongdong Wang,Zhisheng Ren,Huaqiang Zhang,Bai Xue,Haiyan Sun,Jie Lu

doi:10.1155/2019/6845756

Abstract

Early diagnosis is essential for the control and prevention of tuberculosis (TB). The objective of this study was to investigate the feasibility and performance of loop-mediated isothermal amplification (LAMP) in the diagnosis of pulmonary TB in county-level microscopy centers in Qingdao, Eastern China. A total of 523 presumptive TB patients were consecutively recruited between July 2017 and April 2018, and 22 patients were excluded from the analysis. Of 102 culture-positive cases, TB-LAMP identified 91 cases, demonstrating a sensitivity of 89.2%. In comparison, the sensitivity of routine smear microscopy was 69.6% (71/102), which was significantly lower than that of TB-LAMP (P=0.001). In addition, TB-LAMP sensitivities in smear-positive and smear-negative samples were 98.6% and 67.7%, respectively. In conclusion, our data demonstrate that TB-LAMP outperforms conventional smear microscopy in TB diagnosis, which could be used as an alternative method for smear microscopy in resource-limited settings in China.

Highlights

Tuberculosis (TB), caused by Mycobacterium tuberculosis complex (MTBC), remains the major public health concern worldwide [1]
71 of 102 culture-positive samples were detected by the routine smear microscopy, demonstrating a sensitivity of 69.6% (92/102, 95% CI: 60.7%∼ 78.5%), which was significantly lower than that of TBLAMP (P=0.001)
Our findings are in agreement with earlier reports on TB-loop-mediated isothermal amplification (LAMP) evaluations which showed that TB-LAMP could identify most smearpositive TB cases and approximately 67% of smear-negative TB cases [6, 8]

Summary

Introduction

Tuberculosis (TB), caused by Mycobacterium tuberculosis complex (MTBC), remains the major public health concern worldwide [1]. Diagnosis and immediate initiation of treatment are essential component of the WHO’s END Tuberculosis Strategy [2]. Sputum microscopy is the primary method for diagnosing pulmonary tuberculosis in lowincome and middle-income countries [3]. It is rapid, of low cost, and specific in areas where there is a high burden of TB, whereas a major shortcoming of conventional microscopy is its low relatively sensitivity, especially for individuals coinfected with HIV [4]. Mycobacterial culture always requires long incubation time despite yielding satisfactory sensitivity [4]. There is an urgent need for accurate and timely diagnosis that limits morbidity, reduces costs, and improves patients’ outcome

Objectives

Results

Conclusion