Molecular characterization of macrolide resistant Streptococcus pyogenes isolates from pharyngitis patients in Serbia
Molecular characterization of macrolide resistant Streptococcus pyogenes isolates from pharyngitis patients in Serbia
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DOI：
10.1016/j.meegid.2015.05.011
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发表时间：
2015-07-01
影响因子：
3.2
通讯作者：
Mijac, Vera
中科院分区：
文献类型：
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作者：
Opavski, Natasa;Gajic, Ina;Mijac, Vera
2004-2009年间，塞尔维亚报告A组化脓性链球菌(GAS)对大环内酯类抗生素的耐药性稳步上升(9.9%)。然而，目前还没有关于咽大环内酯类耐药气体(MRGAS)分离株的分子流行病学数据。因此，这项第一项全国性研究的目的是检查塞尔维亚GAS中大环内酯类药物耐药性的流行情况，并确定它们的耐药性表型、基因类型和克隆关系。在2008至2009年间，全国共收集了3893株来自门诊胃气感染患者的无重复的化脓性咽链球菌分离株。在收集的486株对大环内酯类抗生素耐药的咽部分离株中，有103株进一步鉴定。采用双纸片扩散法检测大环内酯类抗生素耐药表型，用聚合酶链式反应检测大环内酯类抗生素耐药基因。通过emm分型、多位点序列分型(MLST)、多位点可变串联重复序列分析(MLVA)、噬菌体图谱(PP)和毒力因子图谱(VFP)确定菌株的亲缘关系。总体而言，塞尔维亚分离的气体对大环内酯类抗生素的耐药率为12.5%。M型最常见(71.8%)，其次为IMLS(18.4%)和CMLS(9.7%)。Emm75/MEFA/ST49、emm12/MEFA/ST36和emm77/Erma/Teto/ST63三个克隆复合体占供试菌株的90%以上。虽然MLVA、PP和VFP分别区分了10、20和12种不同的模式，但聚类分析显示，属于同一EMM/ST型的菌株之间的差异很小。我们的数据显示，三种主要的国际广泛传播的大环内酯类耐药性占主导地位。塞尔维亚MRGAS人群中的克隆和高度遗传同质性。今后有必要继续监测塞尔维亚MRGAS的大环内酯类耐药性和克隆构成，以确定MRGAS克隆的稳定性并指导治疗策略。(C)2015爱思唯尔B.V.保留所有权利。
A steady increase in macrolide resistance in Streptococcus pyogenes, group A streptococci (GAS) was reported in Serbia during 2004-2009 (9.9%). However, there are no data on the molecular epidemiology of pharyngeal macrolide resistance GAS (MRGAS) isolates. Therefore, the aims of this first nationwide study were to examine the prevalence of macrolide resistance in Serbian GAS and to determine their resistance phenotypes, genotypes and clonal relationships. Overall 3893 non-duplicate pharyngeal S. pyogenes isolates from outpatients with GAS infection were collected throughout country during 2008 and 2009. Among 486 macrolide resistant pharyngeal isolates collected, 103 were further characterized. Macrolide resistance phenotypes and genotypes were determined by double-disk diffusion test and PCR, respectively. Strain relatedness was determined by emm typing, multilocus sequence typing (MLST), multilocus variable tandem repeat analysis (MLVA), phage profiling (PP) and virulence factor profiling (VFP). Overall, macrolide resistance among GAS isolates in Serbia was 12.5%. M phenotype was the most common (71.8%), followed by iMLS (18.4%) and cMLS (9.7%). Three clonal complexes - emm75/mefA/ST49, emm12/mefA/ST36 and emm77/ermA/tetO/ST63 comprised over 90% of the tested strains. Although MLVA, PP and VFP distinguished 10, 20 and 12 different patterns, respectively, cluster analysis disclosed only small differences between strains which belonged to the same emm/ST type. Our data indicate dominance of three major internationally widely disseminated macrolide resistant. clones and a high genetic homogeneity among the Serbian MRGAS population. Continued surveillance of macrolide resistance and clonal composition in MRGAS in Serbia in future is necessary to determine stability of MRGAS clones and to guide therapy strategies. (C) 2015 Elsevier B.V. All rights reserved.