Resistencia de Staphylococcus aureus a los antibióticos en un hospital de la orinoquia colombiana

Abstract

ObjectiveAnalyze the antimicrobial resistance patterns of Staphylococcus aureus at a hospital in Villavicencio, Colombia from 2005 to 2009. DesignRetrospective cohort study Setting: Villavicencio Departamental Hospital, a second and third level care center Targetpopulation: Patients’ microbiological records showing positive strains for S. aureus were analyzed. InterventionsNone VariableMethicillin resistance OutcomesAntimicrobial resistance ResultsNine hundred and seventy six strains of S. aureus were isolated from 29,451 microbiological screened samples, and their antimicrobial resistance pattern was analyzed by standard micro-dilution broth tests. 49.6% strains were resistant to methicillin, and their co-resistance was higher mainly to gentamycin (25%), ciprofloxacin (25.1%), clindamycin (29.4%) and erythromycin (31.0), but lower to trimethoprim/sulfamethoxazole (11.8%). Although co-resistance to vancomycin was supposed to be low, some intermediate range and resistant isolates were found, but this statement cannot be established because they were not confirmed at a referenced laboratory. Tetracycline resistance was high even for methicillin sensitive stains. No resistance to linezolid was identified. Resistance to tigecycline was not evaluated. ConclusionsS. aureus resistance to methicillin is also common at the target hospital in the Colombian Orinoco region. Co-resistance is higher particularly to gentamycin, ciprofloxacin and clindamycin in methicillin resistant strains. High sensitivity to these antimicrobials is evidenced when S. aureus is also sensitive to methicillin. Some findings related to sensitivity to ciprofloxacin and clindamycin in the presence of methicillin resistance suggest the possibility of community-associated strains in Villavicencio as well as in other Colombian cities. This possibility deserves further confirmatory research.