Epidemiology of resistance and phenotypic characterization of carbapenem resistance mechanisms in isolates at Sahloul University Hospital-Sousse, Tunisia.

Objective: To assess the prevalence of ESBL producing and carbapenem resistant isolated from in-come and out-come patients at Sahloul-university hospital.

Methods: A retrospective study over a 3 years period (January 2012 and December 2014) focused on 2160 strains of . Statistical analysis was carried out using SPSS program. ESBL detection was performed using a double disc diffusion method and carbapenemase detection was realized by Rosco-Disk kit.

Results: A total of 2160 strains were isolated during the period of the study, 26.2% (n=566) were ESBL-producers and 15.8% (n=342) showed resistance to carbapenem. The wards most affected by these strains were basically urology and intensive care units. Eighty four percent of studied strains (203/241) were resistant to temocillin, which correlate with the production of a class D (OXA-48-like) carbapenemase and 7% (17/241) showed sensitivity to EDTA and dipicolinic acid, which indicate the production of metallo-enzyme. The rate of resistance to colistin remains low.

Conclusion: Resistance of , including , to third generation cephalosporins (3rd GC) and carbapenem through the mechanism of ESBL and carbapenemases production is becoming increasingly worrying. This suggests a more rational use of antibiotics, as well as the rigorous application of hygiene measurement.