缅甸仰光发热患者分离的沙门氏菌的抗菌药物耐药分子机制及系统发育关系。

Molecular mechanisms of antimicrobial resistance and phylogenetic relationships of Salmonella enterica isolates from febrile patients in Yangon, Myanmar.

机构信息

Department of Microbiology, University of Medicine 1, No. 245 Myoma Kyaung Street, Lanmadaw Township, Yangon, Myanmar.

Centre for International Health, University of Otago, Dunedin, New Zealand.

出版信息

Trans R Soc Trop Med Hyg. 2019 Oct 11;113(10):641-648. doi: 10.1093/trstmh/trz053.

DOI:10.1093/trstmh/trz053

PMID:31225619

Abstract

BACKGROUND

Enteric fever is common in southeast Asia. However, there is little information on the circulating Salmonella enterica strains causing enteric fever in Myanmar.

METHODS

We performed antimicrobial susceptibility testing and whole genome sequencing on S. enterica bloodstream isolates from febrile patients aged ≥12 y attending two hospitals in Yangon, Myanmar, from 5 October 2015 through 4 October 2016. We identified the serovar of S. enterica, determined antimicrobial susceptibility and the molecular mechanisms of resistance. We analysed phylogenetic relationships among Myanmar S. enterica isolates and those with isolates from neighbouring countries.

RESULTS

Of 73 S. enterica isolated, 39 (53%) were serovar Typhi and 34 (47%) were Paratyphi A. All isolates were susceptible to ampicillin, chloramphenicol and trimethoprim-sulfamethoxazole but resistant to ciprofloxacin. We identified mutations in chromosomal genes gyrA, gyrB and parC as responsible for fluoroquinolone resistance. All S. enterica Typhi isolates were of 4.3.1 subclade (formerly known as H58) and formed two closely related genotypic clusters; both clusters were most closely related to isolates from India from 2012. All S. enterica Paratyphi A were lineage C, clade C4 and were closely related.

CONCLUSION

Our study describes currently circulating S. enterica serovars in Myanmar, the genetic basis of their antimicrobial resistance and provides a genotypic framework for epidemiologic study.

摘要

背景

肠热病在东南亚很常见。然而，关于导致缅甸肠热病的沙门氏菌血清型菌株的信息却很少。

方法

我们对 2015 年 10 月 5 日至 2016 年 10 月 4 日期间，在仰光的两家医院就诊的 12 岁以上发热患者的血流感染沙门氏菌分离株进行了抗生素敏感性测试和全基因组测序。我们确定了沙门氏菌血清型，确定了抗生素敏感性和耐药的分子机制。我们分析了缅甸沙门氏菌分离株与邻国分离株的系统进化关系。

结果

在 73 株分离的沙门氏菌中，39 株（53%）为伤寒血清型，34 株（47%）为甲型副伤寒血清型。所有分离株均对氨苄西林、氯霉素和复方磺胺甲噁唑敏感，但对环丙沙星耐药。我们发现染色体基因 gyrA、gyrB 和 parC 的突变是导致氟喹诺酮耐药的原因。所有伤寒血清型沙门氏菌分离株均为 4.3.1 亚群（以前称为 H58），形成了两个密切相关的基因型簇；两个簇与 2012 年来自印度的分离株最为密切相关。所有甲型副伤寒血清型沙门氏菌均为 C 谱系、C4 分支，关系密切。