Oxacillin- and Quinolone-Resistant Staphylococcus aureus in Sao Paulo, Brazil: A Multicenter Molecular Epidemiology Study

Abstract
To investigate the possibility of interhospital spread of multiresistant Staphylococcus aureus in Sao Paulo, Brazil. We evaluated 13 nosocomial S aureus strains selected because of resistance to oxacillin and ciprofloxacin. The strains were collected between March 1991 and September 1991 from four different hospitals in Sao Paulo. Two were teaching hospitals, and two were private hospitals. Each strain was isolated from a different patient. All patients were hospitalized when the strains were isolated. The strains were typed by restriction endonuclease analyses of plasmid DNA (REAP) using EcoRI, HindIII, RsaI, and AluI and by extended antibiogram profile (34 drugs). All strains had identical plasmid and antibiogram profile. They demonstrated the same plasmid pattern as previously described in one of the hospitals studied. Our results suggest the dissemination of a unique oxacillin- and quinolone-resistant strain of S aureus in several hospitals of Sao Paulo, Brazil.