title: Genotyping of skin and soft tissue infection (SSTI)-associated methicillin-resistant Staphylococcus aureus (MRSA) strains among outpatients in a teaching hospital in Japan: application of a phage-open reading frame typing (POT) kit.
abstract: We aimed to elucidate the current epidemiological features of outpatient skin and soft tissue infection (SSTI)-associated methicillin-resistant Staphylococcus aureus (MRSA) in Japan. Altogether, we evaluated the performance of a phage-open reading frame typing (POT) kit for genotyping these MRSA strains. We collected 57 MRSA strains from all outpatients with SSTIs attending a teaching hospital in Japan. Drug susceptibility measurement and genotyping including SCCmec typing, spa typing, multilocus sequence typing, pulsed-field gel electrophoresis, and commercial POT-kit were performed. The majority of strains (39 strains, 68 %) had the SCCmec-II element. Seventeen strains (30 %) with SCCmec-IV accounted for the second largest population. Strains with SCCmec-IV and SCCmec-V appeared multiclonal, and a predominance of Panton-Valentine leukocidin (PVL) gene-negative CC8/spa-CC008 strains, as well as the first isolate of an ST93 strain in Japan, was observed among them. Only one USA300 strain was identified. Strains with SCCmec-IV and SCCmec-V were significantly susceptible to antimicrobials. The PVL gene was found in 5 SCCmec-IV strains and 1 SCCmec-V strain. The POT-kit successfully predicted the SCCmec type in 54 strains (95 %), and typing by POT1 scores was highly concordant with SCCmec typing and spa typing. Moreover, three PVL-positive strains fell into a particular POT type (POT scores, 106-77-113). Simpson's index of the POT-kit was 0.977. In conclusion, the present study clarified the multiclonal nature of outpatient SSTI-associated MRSA in a teaching hospital in Japan. These data also underscore the utility of the POT-kit for non-outbreak surveillance through its simple platform consisting of two multiplex PCRs without sequencing.
authors.affiliation: Department of Microbiology and Infectious Diseases, Toho University School of Medicine, 5-21-16 Omori-nishi, Ota-ku, Tokyo 143-8540, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Maeda
authors.forename: Tomoo
authors.initials: T
authors.lastname: Saga
authors.forename: Taito
authors.initials: T
authors.lastname: Miyazaki
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kouyama
authors.forename: Sohei
authors.initials: S
authors.lastname: Harada
authors.forename: Morihiro
authors.initials: M
authors.lastname: Iwata
authors.forename: Sadako
authors.initials: S
authors.lastname: Yoshizawa
authors.forename: Soichiro
authors.initials: S
authors.lastname: Kimura
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Ishii
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Urita
authors.forename: Motonobu
authors.initials: M
authors.lastname: Sugimoto
authors.forename: Keizo
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tateda
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D001435:Bacteriophages; D004269:DNA, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D060005:Genotyping Techniques / Q000379:methods; D006784:Hospitals, Teaching; D006801:Humans; D007564:Japan; D016106:Methicillin Resistance / Q000235:genetics; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing / Q000379:methods; D021141:Nucleic Acid Amplification Techniques; D016366:Open Reading Frames; D010045:Outpatients; D018461:Soft Tissue Infections / Q000382:microbiology*; D013207:Staphylococcal Skin Infections / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial