Evolution of antimicrobial resistance in departments with high risk of cross infections in Tunisia

Abstract

Background Antimicrobial resistance is actually a real and ever-changing public health problem. The microbiology laboratory plays a key role to achieve collaboration with clinical services and the prevention and control of infection team. Objective Describe the bacterial ecology of departments with high risk of Health care associated infections and analyze the evolution of antimicrobial resistance. Methods A descriptive and retrospective study was carried out in the university hospital Sahloul. It concerned all strains isolated in departments with high risk of Health care associated infections. The study period was spread over 7 years from January 1st, 2010 to December 31th, 2016. Results A total of 6108 non-redundant bacterial strains were isolated. Isolated pathogens were mainly from the urology departement (n-2651, 43.4%).The most frequent isolated pathogens were Escherichia coli (n = 1329, 21,8%), K. pneumoniae (n = 992, 16,2%), and Acinetobacter baumannii (n = 763, 12,5%). Concerning these main isolated species, significant statistical differences were noticed in bacterial resistance evolution over the years. With E. coli, the evolution was essentially represented by an increase of amoxicillin, amoxicillin clavulanic, cefotaxime, gentamicin, and fluoroquinolones resistance. With K. pneumoniae, cefotaxime resistance was stable, however resistance to imipenem and gentamicin was increasing. There was also a significant increase in fluoroquinolone and aminoside resistance. With S. Aureus, an increase in methicillin resistance was detected from 11.1% in 2010 to 20% in 2016. Conclusions Antibacterial Drug Resistance is a dynamic and rapidly evolving phenomenon in our hospital. The most common MDR bacteria studied were enterobacteriaceae producing carbapenemase. The emergence of glycopeptid resistance in enterococci must be controlled in order to prevent its spread to the community and the transfer of staphylococcus resistance genes. Key messages Antibacterial Drug Resistance is a dynamic and rapidly evolving phenomenon in our hospital. The most common multi drug resistant bacteria studied were enterobacteriaceae producing carbapenemase.