Oxacillin resistance of Staphylococcus aureus isolated from the university hospital of Botucatu Medical School in Brazil.
BACKGROUND
Oxacillin is the main drug used for the treatment of Staphylococcus aureus infections. However, resistance of S. aureus to oxacillin has become a major problem over recent decades. The aim of this study was to determine oxacillin resistance in S. aureus isolates obtained from the University Hospital of the Botucatu Medical School, Universidade Estadual Paulista, Brazil.


METHODS
A total of 102 isolates collected between 2002 and 2006 were analyzed by detection of the mecA gene, cefoxitin and oxacillin disk diffusion methods, screening test on Mueller-Hinton agar and E-test.


RESULTS
Forty-six (45.1%) isolates were mecA positive. The oxacillin disk diffusion method showed 86.9% sensitivity and 91.1% specificity. The screening method and cefoxitin disk diffusion presented a similar sensitivity (91.3%) and the same specificity. The E-test showed 97.8% sensitivity and the same specificity as observed for the other methods.


CONCLUSIONS
The E-test yielded the best results compared to the other methods.
Martins
André
A
Department of Tropical Diseases and Imaging Diagnosis, Botucatu Medical School, UNESP - Univ. Estadual Paulista, São Paulo, Brazil.
Pereira
Valéria Cataneli
VC
Cunha
Maria de Lourdes R S
Mde L
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D001938:Brazil; D002440:Cefoxitin / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D006785:Hospitals, University; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D010068:Oxacillin / Q000494:pharmacology*; D046915:Penicillin-Binding Proteins; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D046915:Penicillin-Binding Proteins; C487789:mecA protein, Staphylococcus aureus; D002440:Cefoxitin; D010068:Oxacillin