title: Streptococcus pyogenes bacteraemia, emm types and superantigen profiles.
abstract: 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.
authors.affiliation: Department of Internal Medicine, Tampere University Hospital, P.O. Box 2000, 33521, Tampere, Finland. sari.rantala@uta.fi
authors.forename: S
authors.initials: S
authors.lastname: Rantala
authors.forename: S
authors.initials: S
authors.lastname: Vähäkuopus
authors.forename: T
authors.initials: T
authors.lastname: Siljander
authors.forename: J
authors.initials: J
authors.lastname: Vuopio
authors.forename: H
authors.initials: H
authors.lastname: Huhtala
authors.forename: R
authors.initials: R
authors.lastname: Vuento
authors.forename: J
authors.initials: J
authors.lastname: Syrjänen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000235:genetics*; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality / Q000473:pathology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D015995:Prevalence; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality / Q000473:pathology; D022541:Streptococcal Vaccines / Q000276:immunology; D013297:Streptococcus pyogenes / Q000145:classification* / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D018089:Superantigens / Q000235:genetics*; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; D022541:Streptococcal Vaccines; D018089:Superantigens; C014689:streptococcal M protein