Molecular characterization of Enterobacteriaceae producing β-lactamase and methicillin-resistant staphylococci isolated from the hospital environment and catheters in two public hospitals in Benin

Abstract

Background: Antimicrobial resistance is a real public health problem. All over the world, it has a considerable impact in hospitals. The present study aims to analyze the presence of resistance genes and bacterial ecology in two hospitals in Benin. Methods: To do this, 146 environmental and catheter samples were collected at the University Hospital Center of Abomey-Calavi / So-Ava and at the Beninese Army Hospital. These samples were inoculated on Mannitol Salt and Eosin Methylene Blue agars. The colonies obtained were identified and their sensitivity to antibiotics was tested, using the usual bacteriological techniques. Four resistance genes encoding the production of extended spectrum beta-lactamases (blaCTX-M1, blaCTX-M2, blaCTX-M9, blaCTX-M15) have been searched in the genome of enterobacteriaceae strains. At the level of staphylococci, the gene coding for methicillin resistance (mecA) was sought.Results: At the end of this study, 69 strains of enterobacteria and 60 of staphylococci were identified. A predominance of Staphylococcus aureus (25.6%) followed by Enterobacter cloacae (21.0%) and coagulase negative staphylococci (21.0%) was noted. These bacterial strains showed to be multidrug-resistant, particularly to beta-lactams, fluoroquinolones, aminoglycosides and macrolides. Beta-lactamases were identified in the genome of bacterial strains with a predominance of blaCTX-M15 (42.8%). The frequency of the mecA gene in staphylococci was 50%.Conclusions: These results show the magnitude of the antimicrobial resistance situation in hospitals. They can be used to support advocacy for urgent action at the national level, especially with regard to the management and efficient use of antimicrobials in Benin.