[Molecular characterization of extended-spectrum ss-lactamases-producing Escherichia coli and Klebsiella pneumoniae in hospitals of the Caribean Region, Colombia].

ESBL-producing in Enterobacteriaceae, is the main resistance mechanism to extended spectrum cephalosporin and monobactams. Seventy isolates collected of hospitals in four cities of the Colombian Caribean, were characterized to ESBL production and metalo-beta-lactamases by microbiological test. The ss-lactamases characterization were performed by IEF and RPC; genotyping by PFGE. Results evidenced the ESBL production at four cities with more frequency in Klebsiella pneumoniae isolated from UCI. The ss-lactamases present in Escherichia coli and in K. pneumoniae contributed co-resistance to different antibiotic families. Enzymes were detected with resistance to cephalosporin and carbapenems, suggesting presence of carbapenemases. Polyclonal isolates noticed, neither demonstrated presence of endemic strains nor association with epidemic outbreak. It is evident the importance to combine clinical, microbiological and molecular information to surveillance the prevalence and evolution of these enzymes in these hospitals.