"Nosocomial infections caused by biofilm-producing staphylococci"

Introduction: In Mexico, one of the main causal agents of nosocomial infections belong to the genus Staphylococcus, bacteria that in many cases have multiresistance to antibiotics and also produce biofilm. Objective: The purpose of the study was to determine the frequency of Staphylococcus spp isolated from various biological samples from patients hospitalized methicillin resistant by detecting the mec A gene and biofilm production by phenotypic detection Agar Congo Red. Materials and Methods: This work was carried out in the Laboratory of Microbiology and Molecular Biology of the Center for Biomedical Research of the UAC. We studied 143 strains of staphylococci donated by the Clinical Analysis Laboratory of a Hospital of the City of San Francisco de Campeche from January 2015 to December 2015. Staphylococcal strains included in this study were isolated from biological samples from patients hospitalized. To phenotypic characterization, strains were cultured on CRA plates in duplicate; while to genotypic detection of gene mecA was done by PCR reaction. Results and conclusions: Our results show that the staphylococcal strains included in this study from infectious processes hospitalized patients have a high frequency of methicillin resistance by detecting the mecA (80.4%) gene and more than half are able of expressing biofilm (55.2%). This gives them not only a resistance to beta-lactam antibiotics but also the ability to produce biofilm, increasing their chances of survival in the face of various adverse events and the use of antibiotics.