Drug resistance characteristics of Mycobacterium tuberculosis isolates obtained between 2018 and 2020 in Sichuan, China.

Ruifeng Zhou,Dongmei Wang,Tianli Zheng,Dongxia Luo,Ma Zhu,Jia Luo,Mingyuan Tang,Xiaofang Pei,Guo Wei,Qingfeng Li,Yuanhong Xu,Xing Zhao,Haojiang Zuo,Chongliang Zeng,Mi Zhou

doi:10.1017/s0950268822000127

Abstract

We investigated the drug resistance of Mycobacterium tuberculosis isolates from patients with tuberculosis (TB) and HIV, and those diagnosed with only TB in Sichuan, China. TB isolates were obtained from January 2018 to December 2020 and subjected to drug susceptibility testing (DST) to 11 anti-TB drugs and to GeneXpert MTB/RIF testing. The overall proportion of drug-resistant TB (DR-TB) isolates was 32.1% (n = 10 946). HIV testing was not universally available for outpatient TB cases, only 29.5% (3227/10 946) cases had HIV testing results. The observed proportion of multidrug-resistant TB (MDR-TB) isolates was almost double than that of the national level, with approximately 1.5% and 0.1% of the isolates being extensively drug resistant and universally drug resistant, respectively. The proportions of resistant isolates were generally higher in 2018 and 2019 than in 2020. Furthermore, the sensitivities of GeneXpert during 2018-2020 demonstrated a downward trend (80.9, 95% confidence intervals (CI) 76.8-85.0; 80.2, 95% CI 76.4-84.1 and 75.4, 95% CI 70.7-80.2, respectively). Approximately 69.0% (7557/10 946) of the TB cases with DST results were subjected to GeneXpert detection. Overall, the DR-TB status and the use of GeneXpert in Sichuan have improved, but DR-TB challenges remain. HIV testing for all TB cases is recommended.

Highlights

Drug-resistant tuberculosis (DR-TB) remains a global issue and serious public health challenge
According to the requirements of the local health department, all TB strains isolated from TB patients in the core area of Sichuan should be sent to this hospital for drug susceptibility testing (DST), or patients should be directly transferred to this hospital for treatment and DST
6,749 isolates were from the outpatient department, 3,197 isolates were from the inpatient department, 945 isolates were from 20 health facilities (16 isolates from district/county Centres for Disease Control and Prevention (CDC), 3 isolates from hospitals, and 1 isolate from a third-party medical testing centre), and 55 isolates were of unknown origin. 120 of these isolates were obtained from patients confirmed with HIV coinfections by laboratory tests

Summary

Introduction

Drug-resistant tuberculosis (DR-TB) remains a global issue and serious public health challenge. In 2019, the incidence of rifampicin-resistant TB was approximately 500,000 worldwide, with 78% of these cases being multidrug-resistant TB (MDR-TB) [1]. Sichuan is one of the most important provinces in Southwest China[6] It comprises 21 regions and 183 counties, with a total area of 486,000 square kilometres. Sichuan has a high incidence of TB of approximately 100 cases per 100,000 people [7], with the second highest TB caseload among the provinces in China [8, 9]. The extensively drug-resistant (XDR)-TB notification rate significantly increased from 2010 to 2017 in Southwest China [10]. 9% of incident TB cases worldwide are among patients with HIV infection [11]. Its detection rate and performance characteristics need to be updated

Methods

Results

Discussion

Conclusion