Molecular screening of multidrug-resistance tuberculosis by a designated public health laboratory in Taiwan

H.-C Lin,H.-A Lin,R Jou,T.-S Chiueh,C.-L Perng,F.-G Lin,C.-J Chiang,Y.-W Lai

doi:10.1007/s10096-017-3082-9

Abstract

This manuscript describes our experience in early identifying MDR-TB cases in high-risk populations by setting up a single-referral molecular diagnosis laboratory in Taiwan. Taiwan Centers for Disease Control designated a single-referral laboratory to provide the GenoType MTBDRplus test for screening high-risk MDR-TB populations nationwide in 2012–2015. A total of 5,838 sputum specimens from 3,308 patients were tested within 3 days turnaround time. Compared with the conventional culture and drug susceptibility testing, the overall performance of the GenoType MTBDRplus test for detecting TB infection showed accuracy of 70.7%, sensitivity of 85.9%, specificity of 65.7%, positive predictive value of 45.5%, and negative predictive value of 93.3%. And the accuracy of detecting rifampin (RIF) resistance, isoniazid (INH) resistance, and MDR-TB (resistant to at least RIF and INH) were 96.5%, 95.2%, and 97.7%, respectively. MDR-TB contacts presented a higher rate of mutated codons 513–519, GenoType MTBDRplus banding pattern: rpoB WT3(−), and rpoB WT4(−) than the treatment failure group. The MDR-TB contact group also had a higher rate of inhA C15T mutation, banding pattern: inhA WT1(−), and inhA MUT1(+) than the recurrent group. Resistance profiles of MDR-TB isolates also varied geographically. The referral molecular diagnosis system contributed to rapid detection and initiation of appropriate therapy.

Highlights

Tuberculosis (TB) is a major health challenge in Taiwan, where it is endemic [1]
A hospital-based study which evaluated 1961 Taiwanese TB patients between 2003 and 2007 showed that 11.7% of the patients were resistant to INH, 2.8% were resistant to RIF, 2.5% were resistant to EMB, and 11.1% were resistant to streptomycin (SM)
Other studies from Taiwan have shown that 10.1% of the M. tuberculosis strains were resistant to INH, 6.2% were resistant to RIF, 2.1% were resistant to EMB, and 9.8% were resistant to SM

Summary

Introduction

The resurgence of TB in recent years has been shown to correlate with an increase in M. tuberculosis isolates which are resistant to one or more of the first-line treatment drugs [2]. A hospital-based study which evaluated 1961 Taiwanese TB patients between 2003 and 2007 showed that 11.7% of the patients were resistant to INH, 2.8% were resistant to RIF, 2.5% were resistant to EMB, and 11.1% were resistant to streptomycin (SM). Other studies from Taiwan have shown that 10.1% of the M. tuberculosis strains were resistant to INH, 6.2% were resistant to RIF, 2.1% were resistant to EMB, and 9.8% were resistant to SM. 18.1% of these strains were resistant to any of the first-line drugs, and 4% were MDR [4,5,6]. The rates of MDR-TB among new cases and previously treated cases in Taiwan were 1.1% and 6–7% respectively [7]

Objectives

Methods

Results

Discussion

Conclusion