“Análisis molecular del gen regulador de virulencia agr en cepas de staphylococcus aureus aisladas de superficies inertes en el área clínica y hospitalaria.”

Abstract

Inert surfaces favor the persistence of Staphylococcus aureus as reservoirs and contamination media in hospital and clinical environments. The pathogenicity of this bacterium is controlled by the accessory gene regulator (agr) system. Objective: To identify the presence of virulence genes in S. aureus isolated strains in inert surfaces and their relationship with the mecA gene (the gene responsible for resistance to methicillin MRSA). Materials and methods: The presence of toxin genes (lukS/lukF-PV) and the mecA gene (MRSA) had already been detected in 59 isolated strains of S. aureus from inert surfaces that were stored in the Laboratory of Molecular Biology and Genetics of the Catholic University of Cuenca. Multiplex PCR was used to determine the agr groups. Results: From the 59 S. aureus strains, 66.1% resulted in agrI, 8.5% in agrII, 18.6% in agrIII, and agrIV was not present in any of the strains. In this study, a statistically significant relationship was found between the presence of agrI and MRSA with p<0.049* value. Conclusions: Molecular typing of agr genes is essential for monitoring epidemic MRSA strains' emergence, spread, and persistence. Improving disinfection techniques on inert surfaces will help infection control in clinic and hospital environments to prevent the propagation of S. aureus.