title: Prevalence and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus in ocular infections.
abstract: OBJECTIVE
  To study the prevalence of methicillin-resistant Staphylococcus aureus among S. aureus ocular infections in a tertiary health center in Brazil and compare antibiotic susceptibility patterns between MRSA and methicillin-susceptible S. aureus isolates.
  
  
  METHODS
  Electronic records from the ocular microbiology laboratory of the Universidade Federal de São Paulo were retrospectively reviewed. During a 10-year period (between January 2000 and December 2009) all conjunctivitis, keratitis, and endophthalmitis cases with a positive culture for S. aureus were identified. Antibiotic susceptibility was determined using the Kirby-Bauer disk diffusion method.
  
  
  RESULTS
  Five hundred sixty-six S. aureus isolates were identified; of those, 56 (9.9%) were resistant to methicillin. Throughout the 10-year period, Staphylococcus aureus showed a significant increasing trend from 7.55% to 16.18% among overall S. aurues infections (p=0.001) and from 3.7% to 13.16% in conjunctivitis (p=0.001). Conversely, we did not observe the same trend among those with keratitis (p=0.38). Staphylococcus aureus isolates showed higher resistance rates to tobramycin, gentamicin, ciprofloxacin, gatifloxacin, and moxifloxacin when compared with S. aureus isolates (p< 0.001). All cases were susceptible to vancomycin.
  
  
  CONCLUSIONS
  We observed an increasing trend in the overall prevalence of Staphylococcus aureus ocular infections and statistically significant higher resistance rates to commonly used antibiotics compared to Staphylococcus aureus. Our data supports the need for constant bacterial surveillance and should be taken into consideration before initiating empiric treatment of ocular infections.
authors: Maria Eugenia
authors: ME
authors: Vola
authors: Aline Silveira
authors: AS
authors: Moriyama
authors: Renato
authors: R
authors: Lisboa
authors: Maria Magdalena
authors: MM
authors: Vola
authors: Flávio Eduardo
authors: FE
authors: Hirai
authors: Paulo José Martins
authors: PJ
authors: Bispo
authors: Ana Luisa
authors: AL
authors: Höfling-Lima
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001938:Brazil / Q000453:epidemiology; D002648:Child; D003231:Conjunctivitis / Q000453:epidemiology; D024881:Drug Resistance, Bacterial; D009877:Endophthalmitis / Q000453:epidemiology; D015818:Eye Infections, Bacterial / Q000188:drug therapy / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007634:Keratitis / Q000453:epidemiology; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000453:epidemiology*; D062606:Tertiary Care Centers; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents