title: Epidemiological study of erythromycin-resistant Streptococcus pyogenes from Korea and Japan by emm genotyping and multilocus sequence typing.
abstract: BACKGROUND
  We determined the epidemiological characteristics of erythromycin (EM)-resistant Streptococcus pyogenes (group A streptococci, GAS) strains isolated from Korea and Japan, using emm genotyping and multilocus sequence typing (MLST).
  
  
  METHODS
  Clinical isolates of GAS had been collected from 1992 to 2012 in Korea and from 2004 to 2009 in Japan. EM resistance was determined by the microdilution method, and resistance genotypes were assessed by PCR. The emm genotyping and MLST were performed by DNA sequencing.
  
  
  RESULTS
  The emm genotypes and sequence types (STs) were concordant in 143 (85.1%) of 168 EM-resistant GAS strains from Korea. ST36/emm12 (35.1%), ST52/emm28 (22.6%), and ST49/emm75 (16.1%) were the most common types. Most of the ST36 (93.9%) and ST52 (95.8%) strains harbored erm(B), whereas strains ST49, ST42, and ST15 contained mef(A). The concordance between emm genotypes and STs was 41 (93.2%) among 44 EM-resistant GAS strains from Japan. ST36/emm12 (34.1%), ST49/emm75 (18.2%), and ST28/emm1 (15.9%) were the major types. ST36 isolates harbored either erm(B) (56.3%) or mef(A) (37.5%), whereas isolates ST28, ST49, and ST38 carried only mef(A). The proportion of erm(B) and mef(A) was 66.1% and 33.3% in Korea and 22.7% and 68.2% in Japan, respectively.
  
  
  CONCLUSIONS
  The common STs in Korea and Japan were ST36 and ST49, whereas ST52 was present only in Korea and ST28 only in Japan. Genotype erm(B) was predominant in Korea, whereas mef(A) was frequent in Japan. There were differences between Korea and Japan regarding the frequencies of emm genotypes, STs, and EM resistance genes among the EM-resistant GAS.
authors.affiliation: Laboratory of Infectious Diseases, Kitasato Institute for Life Sciences & Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Laboratory of Infectious Diseases, Kitasato Institute for Life Sciences & Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Arai
authors.affiliation: Department of Laboratory Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Department of Laboratory Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Eun Ha
authors.initials: EH
authors.lastname: Koh
authors.affiliation: Laboratory of Infectious Diseases, Kitasato Institute for Life Sciences & Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.
authors.forename: Haruno
authors.initials: H
authors.lastname: Yoshida
authors.affiliation: Department of Microbiology and Infectious Diseases, Nara Medical University, Nara, Japan.
authors.forename: Hisakazu
authors.initials: H
authors.lastname: Yano
authors.affiliation: Department of Infection Control and Laboratory Diagnostics, Tohoku University Graduate School of Medicine, Miyagi, Japan.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kaku
authors.affiliation: Department of Laboratory Medicine, Gyeongsang National University School of Medicine, Jinju, Korea. sjkim8239@hanmail.net.
authors.forename: Sunjoo
authors.initials: S
authors.lastname: Kim
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001426:Bacterial Proteins / Q000235:genetics*; D015373:Bacterial Typing Techniques; D024881:Drug Resistance, Bacterial; D016021:Epidemiologic Studies; D004917:Erythromycin / Q000494:pharmacology* / Q000627:therapeutic use; D005838:Genotype; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D056910:Republic of Korea / Q000453:epidemiology; D013290:Streptococcal Infections / Q000188:drug therapy / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004917:Erythromycin
keywords: Erythromycin; Genotypes; Resistance; Sequence types; Streptococcus pyogenes