Characterization of methicillin-resistant Staphylococcus aureus isolated from tertiary care hospitals in Tokyo, Japan.
The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) remains problematic in both hospital and community settings. Investigations of MRSA existing in the local area are necessary to understand the detailed epidemiology of healthcare-associated MRSA (HA-MRSA). In the present study, molecular epidemiological analysis was performed on 584 MRSA isolated from four hospitals in Tokyo, Japan. In the pulsed-field gel electrophoresis (PFGE) analysis, four epidemic pulsotypes (I to IV) were found. The isolates of the epidemic pulsotype I mainly consisted of the SCCmec type II, toxic shock syndrome toxin 1 gene (tst)-negative, spa type t002, and ST764 clones. The ST764 clone, which is a novel hybrid variant of the ST5 HA-MRSA lineage with the arginine catabolic mobile element (ACME), was first found in Niigata, Japan. However, no ACME genes were detected in the isolates of the epidemic pulsotype I. In contrast, the other isolates of the epidemic pulsotypes mainly consisted of the SCCmec type II, tst-positive, spa type t002, and ST5 clones, which are the most predominant clones of HA-MRSA in Japan. Resistance rates of non-β-lactams for the isolates of the epidemic pulsotype I were higher than those of the other epidemic pulsotypes. Our data showed that the novel ACME-negative ST764 clones are being distributed throughout multiple hospitals in Tokyo. The ST764 clones in Tokyo have the potential to acquire ACME in the future, because the ACME-positive ST764 clones have already been found in both hospital and community settings in other areas of Japan.
Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
Hidemasa
H
Nakaminami
Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. Electronic address: noguchin@toyaku.ac.jp.
Norihisa
N
Noguchi
Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
Ayumu
A
Ito
Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
Masashi
M
Ikeda
Department of Respiratory Medicine, Tokyo Medical University Hachioji Medical Centre, 1163 Tatemachi, Hachioji, Tokyo 193-0998, Japan.
Kenta
K
Utsumi
Department of Surgery, Nippon Medical School Tama Nagayama Hospital, 1-7-1 Nagayama, Tama, Tokyo 206-8512, Japan.
Hiroshi
H
Maruyama
Department of Oral Surgery, Tokai University Hachioji Hospital, 1838 Ishikawa, Hachioji, Tokyo 192-0032, Japan.
Haruo
H
Sakamoto
Department of Nursing, National Hospital Organisation Disaster Medical Centre, 3256 Midori, Tachikawa, Tokyo 190-0014, Japan.
Masako
M
Senoo
Department of Neurosurgery, National Hospital Organisation Disaster Medical Centre, 3256 Midori, Tachikawa, Tokyo 190-0014, Japan.
Yoshio
Y
Takasato
Department of Internal Medicine, Akiru Municipal Medical Centre, 78-1 Hikita, Akiruno, Tokyo 197-0834, Japan.
Susumu
S
Nishinarita
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification* / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D017720:Molecular Epidemiology; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D063128:Tertiary Health Care
D000900:Anti-Bacterial Agents
Community-acquired methicillin-resistant Staphylococcus aureus; Health-care associated methicillin-resistant Staphylococcus aureus; ST5; ST764