title: Molecular Characterization of Invasive Streptococcus dysgalactiae subsp. equisimilis, Japan.
abstract: We collected β-hemolytic streptococci (1,611 isolates) from patients with invasive streptococcal infections in Japan during April 2010-March 2013. Streptococcus dysgalactiae subsp. equisimilis (SDSE) was most common (n = 693); 99% of patients with SDSE infections were elderly (mean age 75 years, SD ±15 years). We aimed to clarify molecular and epidemiologic characteristics of SDSE isolates and features of patient infections. Bacteremia with no identified focus of origin and cellulitis were the most prevalent manifestations; otherwise, clinical manifestations resembled those of S. pyogenes infections. Clinical manifestations also differed by patient's age. SDSE isolates were classified into 34 emm types; stG6792 was most prevalent (27.1%), followed by stG485 and stG245. Mortality rates did not differ according to emm types. Multilocus sequence typing identified 46 sequence types and 12 novel types. Types possessing macrolide- and quinolone-resistance genes were 18.4% and 2.6%, respectively; none showed β-lactam resistance. Among aging populations, invasive SDSE infections are an increasing risk.
authors.forename: Takeaki
authors.initials: T
authors.lastname: Wajima
authors.forename: Miyuki
authors.initials: M
authors.lastname: Morozumi
authors.forename: Shigeo
authors.initials: S
authors.lastname: Hanada
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Sunaoshi
authors.forename: Naoko
authors.initials: N
authors.lastname: Chiba
authors.forename: Satoshi
authors.initials: S
authors.lastname: Iwata
authors.forename: Kimiko
authors.initials: K
authors.lastname: Ubukata
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000942:Antigens, Bacterial / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D013290:Streptococcal Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D013291:Streptococcus / Q000145:classification* / Q000187:drug effects / Q000235:genetics*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; C014689:streptococcal M protein
keywords: Japan; Streptococcus dysgalactiae subsp. equisimilis; bacteria; emm type; multilocus sequence typing; streptococci