Department of Internal Medicine, Tampere University Hospital, P.O. Box 2000, 33521, Tampere, Finland.
Eur J Clin Microbiol Infect Dis. 2012 May;31(5):859-65. doi: 10.1007/s10096-011-1385-9. Epub 2011 Aug 30.
The aim of this study was to investigate the emm types and superantigen profiles of bacteraemic group A streptococcal (GAS; Streptococcus pyogenes) isolates and to detect possible associations between the molecular characteristics of isolates and the clinical presentations of disease. In this population-based study, 87 bacteraemic GAS isolates from adult patients in Pirkanmaa Health District (HD), Finland, during the period 1995-2004 were emm typed and genotyped for superantigen (SAg) profiles. The epidemiological and clinical data of the patients were analysed with the microbiological characterisation data. Among the 87 isolates, 18 different emm types were found. emm1, emm28 and emm81 were the three most common types, covering 52% of isolates. The prevalence of specific emm types showed high variability during the 10-year study period. We could not find any association between the emm type and clinical features of bacteraemic infection, such as underlying diseases, disease manifestations or case fatality. Of nine superantigen genes examined, speA and speC were identified in 20 and 30% of the strains, respectively. No association was found between disease manifestation and the presence of single superantigen genes. The 26-valent GAS vaccine would have covered only 62% of isolates causing invasive disease in Pirkanmaa HD during the study period.
本研究旨在调查血流感染 A 组链球菌（GAS；酿脓链球菌）分离株的 emm 型和超抗原谱，并检测分离株的分子特征与疾病临床表现之间可能存在的关联。在这项基于人群的研究中，对芬兰皮尔卡区卫生区（HD）1995-2004 年期间 87 例成人血流感染 GAS 分离株进行 emm 型分型和超抗原（SAg）谱基因分型。对患者的流行病学和临床数据与微生物学特征数据进行了分析。在 87 株分离株中，发现了 18 种不同的 emm 型。emm1、emm28 和 emm81 是三种最常见的类型，占分离株的 52%。在 10 年的研究期间，特定 emm 型的流行率表现出高度的可变性。我们没有发现 emm 型与血流感染的临床特征之间存在任何关联，如基础疾病、疾病表现或病死率。在检查的 9 个超抗原基因中，speA 和 speC 分别在 20%和 30%的菌株中被鉴定出来。在疾病表现与单个超抗原基因的存在之间未发现关联。在研究期间，皮尔卡区卫生区引起侵袭性疾病的分离株中，26 价 GAS 疫苗仅能覆盖 62%。
