Hospital epidemiology and antibiotic resistance in clinical isolates of Enterobacter cloacae

In thIe latter years Enterobacter cloacae has been counted as a very important occasional pathogen, above all in causing hospital infections.The micro-organism’s interesting increases because of its high resistance in vitro to many antimicrobial agents. For this reason it would be possible to find out others resistance mutant phenotypes. The results (2000-2001 and the first six months of 2002), carried out 341 isolated samples from hospital patients, show that the percentage of these E. cloacae is little more than 1%, increasing prevalence of patients belonging to General Surgery and Intensive Care Unit. The susceptible tests suggest (without important differences during the whole year) that most of the clinical isolates have moderate or high level resistance to various antimicrobial agents (penicillins, cephalosporins, aminoglycosides, quinolones, monobactam) and almost all were susceptible to amikacin, carbapenems (imipenem) and trimethoprim/sulfmamethoxazolo. Always regarding the resistance of these pathogens, it was possible to find out some phenotypes, and one of these, among 172 isolates belonging to Intensive Care Unit, was a particular multiresistance phenotype. The VITEK ESßL detection test and the conventional double disk synergy test for detection of ESßL find out some phenotypes showing expression of stably derepressed beta-lactamase.