title: Prevalence of resistance phenotypes in Staphylococcus aureus and coagulase-negative isolates of venous ulcers of primary healthcare patients.
abstract: BACKGROUND
  In venous ulcers, the presence of Staphylococcus aureus and coagulase-negative staphylococcus resistance phenotypes can aggravate and limit the choices for treatment.
  
  
  METHODS
  Staphylococcus isolated from 69 patients (98 ulcers) between October of 2009 and October of 2010 were tested. The macrolide, lincosamide, streptogramin B (MLS B) group resistance phenotype detection was performed using the D-test. Isolates resistant to cefoxitin and/or oxacillin (disk-diffusion) were subjected to the confirmatory test to detect minimum inhibitory concentration (MIC), using oxacillin strips (E-test®).
  
  
  RESULTS
  The prevalence of S. aureus was 83%, and 15% of coagulase-negative staphylococcus (CoNS). In addition were detected 28% of methicillin-resistant Staphylococcus aureus (MRSA) and 47% of methicillin-resistant coagulase-negative staphylococcus (MRCoNS). Among the S. aureus, 69.6% were resistant to erythromycin, 69.6% to clindamycin, 69.6% to gentamicin, and 100% to ciprofloxacin. Considering the MRSA, 74% were highly resistant to oxacillin, MIC ≥ 256µg/mL, and the MLS Bc constitutive resistance predominated in 65.2%. Among the 20 isolates sensitive to clindamycin, 12 presented an inducible MLS B phenotype. Of the MRCoNS, 71.4%were resistant to erythromycin, ciprofloxacin and gentamicin. Considering the isolates positive for β-lactamases, the MIC breakpoint was between 0.5 and 2µg/mL.
  
  
  CONCLUSIONS
  The results point to a high occurrence of multi-drug resistant bacteria in venous ulcers in primary healthcare patients, thus evidencing the need for preventive measures to avoid outbreaks caused by multi-drug resistant pathogens, and the importance of healthcare professionals being able to identifying colonized versus infected venous ulcers as an essential criteria to implementing systemic antibacterial therapy.
authors.affiliation: Programa de Pós-Graduação em Ciências da Saúde, Universidade Federal de Goiás, Goiânia, GO. marlenianapower@hotmail.com
authors.forename: Marlene Andrade
authors.initials: MA
authors.lastname: Martins
authors.forename: Silvana de Lima Vieira Dos
authors.initials: Sde L
authors.lastname: Santos
authors.forename: Lara Stefânia Netto de Oliveira
authors.initials: LS
authors.lastname: Leão
authors.forename: Nayara Portilho
authors.initials: NP
authors.lastname: Araújo
authors.forename: Maria Márcia
authors.initials: MM
authors.lastname: Bachion
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003030:Coagulase / Q000378:metabolism; D003430:Cross-Sectional Studies; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D006801:Humans; D055231:Lincosamides / Q000494:pharmacology*; D018942:Macrolides / Q000494:pharmacology*; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus; D008826:Microbial Sensitivity Tests / Q000379:methods; D008875:Middle Aged; D010641:Phenotype; D015995:Prevalence; D011320:Primary Health Care; D013211:Staphylococcus aureus / Q000145:classification / Q000187:drug effects* / Q000201:enzymology; D025382:Streptogramin Group B / Q000494:pharmacology*; D014647:Varicose Ulcer / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents; D003030:Coagulase; D055231:Lincosamides; D018942:Macrolides; D025382:Streptogramin Group B