Evaluación de métodos fenotípicos para la detección de Staphylococcus aureus resistente a meticilina

Translated title of the contribution: Phenotypic methods for detection of methicillin-resistant Staphylococcus aureus

Gertrudis Horna, Lizeth Astocondor, Jan Jacobs, Coralith García

Research output: Contribution to journalArticle

1 Scopus citations


Background. Cefoxitin is a potent inducer of the mecA gene. It is currently as a screening recommended method for presumptive identification of isolates of methicillin resistant Staphylococcus aureus (MRSA). The aim of the study was to compare the sensitivity and specificity of the cefoxitin disc diffusion (30μg) to oxacillin agar screening from detection of the mecA gene by PCR. Methods. Three hundred thirty-one strains of S. aureus isolated from blood cultures of patients from hospitals in Lima were used in the study. The following tests were performed: oxacillin screening agar (plates were inoculated with 4% NaCl and 6 mg/L of oxacillin), cefoxitin disc diffusion test (30 ug) and PCR to amplify the mecA gene. Results. The mecA gene was detected in 165 out of 331 S. aureus isolates. Thus, the frequency of detection of MRSA was 50%. The evaluation of the cefoxitin disc diffusion test showed a 96.3% and 90.9% of sensitivity and specificity, respectively. Conclusion. Cefoxitin disc diffusion test correlated well with detection of the mecA gene by PCR. Therefore, this test can be an alternative to PCR for detection of MRSA in limited resources settings.

Original languageSpanish
Pages (from-to)98-100
Number of pages3
JournalRevista Espanola de Quimioterapia
Issue number2
StatePublished - Sep 1 2015
Externally publishedYes



  • Cefoxitin
  • Heteroresistance
  • MecA gene
  • Methicillin-resistant Staphylococcus aureus

ASJC Scopus subject areas

  • Pharmacology
  • Microbiology (medical)
  • Medicine(all)

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