title: Streptococcus pyogenes Pneumonia in Adults: Clinical Presentation and Molecular Characterization of Isolates 2006-2015.
abstract: BACKGROUND
  In the preantibiotic era Streptococcus pyogenes was a common cause of severe pneumonia but currently, except for postinfluenza complications, it is not considered a common cause of community-acquired pneumonia in adults.
  This study aimed to identify current clinical episodes of S. pyogenes pneumonia, its relationship with influenza virus circulation and the genotypes of the involved isolates during a decade in a Southern European region (Gipuzkoa, northern Spain). Molecular analysis of isolates included emm, multilocus-sequence typing, and superantigen profile determination.
  
  
  RESULTS
  Forty episodes were detected (annual incidence 1.1 x 100,000 inhabitants, range 0.29-2.29). Thirty-seven episodes were community-acquired, 21 involved an invasive infection and 10 developed STSS. The associated mortality rate was 20%, with half of the patients dying within 24 hours after admission. Influenza coinfection was confirmed in four patients and suspected in another. The 52.5% of episodes occurred outside the influenza seasonal epidemic. The 67.5% of affected persons were elderly individuals and adults with severe comorbidities, although 13 patients had no comorbidities, 2 of them had a fatal outcome. Eleven clones were identified, the most prevalent being emm1/ST28 (43.6%) causing the most severe cases.
  
  
  CONCLUSIONS
  S. pyogenes pneumonia had a continuous presence frequently unrelated to influenza infection, being rapidly fatal even in previously healthy individuals.
authors.affiliation: Biomedical Research Center Network for Respiratory Diseases (CIBERES), San Sebastián, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Tamayo
authors.affiliation: Biomedical Research Center Network for Respiratory Diseases (CIBERES), San Sebastián, Spain.|Microbiology Department, Hospital Universitario Donostia-Instituto Biodonostia, San Sebastián, Spain.
authors.forename: Milagrosa
authors.initials: M
authors.lastname: Montes
authors.affiliation: Biomedical Research Center Network for Respiratory Diseases (CIBERES), San Sebastián, Spain.|Microbiology Department, Hospital Universitario Donostia-Instituto Biodonostia, San Sebastián, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Vicente
authors.affiliation: Biomedical Research Center Network for Respiratory Diseases (CIBERES), San Sebastián, Spain.|Microbiology Department, Hospital Universitario Donostia-Instituto Biodonostia, San Sebastián, Spain.|Medicine Faculty, University of the Basque Country, UPV/EHU, San Sebastián, Spain.
authors.forename: Emilio
authors.initials: E
authors.lastname: Pérez-Trallero
mesh_terms: D000328:Adult; D000942:Antigens, Bacterial / Q000235:genetics*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D009026:Mortality; D018410:Pneumonia, Bacterial / Q000235:genetics / Q000401:mortality / Q000473:pathology / Q000503:physiopathology; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology; D013290:Streptococcal Infections / Q000235:genetics / Q000401:mortality / Q000473:pathology / Q000503:physiopathology; D013297:Streptococcus pyogenes / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; C014689:streptococcal M protein