Prevalence of Chlamydia trachomatis Genotypes in Men Who Have Sex with Men and Men Who Have Sex with Women Using Multilocus VNTR Analysis-ompA Typing in Guangzhou, China.

Xiaolin Qin,Yinyuan Lan,Xuqi Ren,Jinmei Huang,Sanmei Tang,Yaohua Xue,Bin Yang,Shujie Huang,Jiangli Ou,Weiying Zeng,Heping Zheng,Xingzhong Wu,Yung-Fu Chang

doi:10.1371/journal.pone.0159658

Abstract

BackgroundChlamydia trachomatis is one of the most prevalent bacterial sexually transmitted infection in China. Although C. trachomatis genotypes can be discriminated by outer membrane protein gene (ompA) sequencing, currently available methods have limited resolutions. This study used a high-resolution genotyping method, namely, multilocus variable number tandem-repeat analysis with ompA sequencing (MLVA)-ompA, to investigate the local epidemiology of C. trachomatis infections among men who have sex with men (MSM) and men who have sex with women (MSW) attending a sexually transmitted diseases (STD) clinic in Guangzhou, China.MethodsRectal specimens from MSM and urethral specimens from MSW were collected between January 2013 and July 2014 at the Guangdong Provincial Center STD clinic. The specimens were sent to the laboratory for analyses. All specimens that were tested positive for C. trachomatis by the commercial nucleic acid amplification tests were genotyped by MLVA-ompA.ResultsFifty-one rectal specimens from MSM and 96 urethral specimens from MSW were identified with C. trachomatis. One hundred and forty-four of the 147 specimens were fully genotyped by MLVA-ompA. Rectal specimens from MSM were divided into four ompA genotypes and urethral specimens from MSW into nine genotypes. No mixed infections were found among all specimens. The most frequent genotypes were D, G, J, E and F. All specimens were further divided into 46 types after ompA genotyping was combined with MLVA. Genotypes D-8.7.1 and G-3.4a.3 were the most frequent among MSM, whereas genotypes D-3.4a.4, E-8.5.1, F-8.5.1, and J-3.4a.2 were the most frequent subtypes among MSW. The discriminatory index D was 0.90 for MLVA, 0.85 for ompA, and 0.95 for MLVA-ompA.ConclusionsThe most prevalent MLVA-ompA genotypes were significantly different between MSM and MSW from Guangzhou, China. Moreover, MLVA-ompA represented a more favorable degree of discrimination than ompA and could be a reliable complement for ompA for the routine subtypes of C. trachomatis.

Highlights

Chlamydia trachomatis is one of the most common bacterial sexually transmitted infections (STIs) in China [1,2,3]
Fifty-one rectal specimens from men who have sex with men (MSM) and 96 urethral specimens from men who have sex with women (MSW) were identified with C. trachomatis
The most prevalent MLVA-ompA genotypes were significantly different between MSM and MSW from Guangzhou, China

Summary

Introduction

Chlamydia trachomatis is one of the most common bacterial sexually transmitted infections (STIs) in China [1,2,3]. Data from 15 sexually transmitted disease (STD) surveillance points in China show that the number of reported cases of C. trachomatis has been increasing annually. In Guangdong Province, the incidence of reported cases of C. trachomatis infections increased from 0.5 per population of 100,000 in 2006 to 49.95 per population of 100,000 in 2013 [6, 7]. Chlamydia trachomatis is one of the most prevalent bacterial sexually transmitted infection in China. This study used a high-resolution genotyping method, namely, multilocus variable number tandem-repeat analysis with ompA sequencing (MLVA)-ompA, to investigate the local epidemiology of C. trachomatis infections among men who have sex with men (MSM) and men who have sex with women (MSW) attending a sexually transmitted diseases (STD) clinic in Guangzhou, China

Objectives

Methods

Conclusion