title: Oxacillin resistance and antimicrobial susceptibility profile of Staphylococcus saprophyticus and other staphylococci isolated from patients with urinary tract infection.
abstract: BACKGROUND
  Staphylococcus saprophyticus is the second most frequent community-acquired causative agent of urinary tract infection (UTI). The objective of this study was to evaluate the susceptibility profile and resistance detection in Staphylococcus species. isolated from patients with UTI.
  
  
  METHODS
  The isolates were investigated using the disk diffusion method, Vitek I system, E-test®, and detection of the mecA gene.
  
  
  RESULTS
  Most isolates (76.2%) were resistant to oxacillin by the disk diffusion method, followed by those resistant to penicillin (72.2%). The oxacillin disk diffusion method, E-test, and Vitek I method showed higher sensitivity (94.4%) and lower specificity (28.9, 26.5, and 24.0%, respectively) than the cefoxitin disk diffusion test (sensitivity: 83.5%, specificity: 85.5%) for the detection of oxacillin resistance.
  
  
  CONCLUSIONS
  The large number of oxacillin-resistant isolates indicates that the breakpoint value recommended by the Clinical and Laboratory Standards Institute may overestimate oxacillin resistance in S. saprophyticus. Thus, changes in these guidelines are necessary for the correct detection of this resistance.
authors.affiliation: Department of Microbiology and Immunology, Botucatu Biosciences Institute, Universidade Estadual Paulista, Botucatu, SP 18618-970, Brazil.
authors.forename: Adriano M
authors.initials: AM
authors.lastname: Ferreira
authors.forename: Mariana F
authors.initials: MF
authors.lastname: Bonesso
authors.forename: Alessandro L
authors.initials: AL
authors.lastname: Mondelli
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Camargo
authors.forename: Maria de Lourdes R S
authors.initials: Mde L
authors.lastname: Cunha
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D052978:Disk Diffusion Antimicrobial Tests / Q000379:methods; D024881:Drug Resistance, Bacterial; D006801:Humans; D010068:Oxacillin / Q000494:pharmacology*; D017410:Practice Guidelines as Topic; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology; D013210:Staphylococcus / Q000187:drug effects* / Q000302:isolation & purification; D057790:Staphylococcus saprophyticus / Q000187:drug effects* / Q000302:isolation & purification; D014552:Urinary Tract Infections / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D010068:Oxacillin