Methicillin-resistant Staphylococcus aureus (MRSA) isolated in clinics and hospitals in the Fukuoka city area.

Bacteriological and clinical studies were carried out on 280 strains of Staphylococcus aureus isolated in clinics and hospitals in the Fukuoka city area from September 1990 to March 1991. The percentage of methicillin-resistant S. aureus (MRSA) strains studied was 41.4% (116 of 280). Of 116 MRSA strains, 48 (41.3%) produced coagulase VII and 21 (18.1%) produced coagulase II. The mean age of the patients who harboured MRSA, 70.5 +/- 16.9 years, was significantly higher than that of patients with methicillin-sensitive S. aureus (MSSA), 44.2 +/- 29.3 years (P < 0.001). MRSA was detected more frequently than MSSA in sputum (P < 0.01), while MSSA was detected more frequently than MRSA in pus (P < 0.01). Ninety (89.1%) of 101 strains of MRSA were isolated from inpatients and 98 (71.0%) of 130 strains of MSSA were isolated from outpatients. Similar number of MRSA strains were recovered in a variety of hospitals, indicating that there was no relationship between hospital size (number of beds) and the incidence of MRSA. As for drug susceptibility, coagulase VII-producing MRSA strains were more sensitive to clidamycin (P < 0.01) and more resistant to minocycline (P < 0.01) than were other MRSA strains.