[Resistance to cefepime in Enterobacter cloacae isolates from hospitals in Bogotá, Colombia].
OBJECTIVE
The aim of this research was to detect the presence of genes encoding beta-lactamases which can confer cefepime resistance on Enterobacter cloacae isolates, meaning that this antibiotic may be considered an important therapeutic alternative.


METHODS
28 E. cloacae isolates collected from 4 hospitals in Bogotá during 2003 were analysed. Extended spectrum beta-lactamases and cephalosporinase production were phenotypically determined. The presence of extended spectrum beta-lactamase genes was determined by PCR amplification. Mating assays were done to determine the possible transfer of bla-genes encoding cefotaximases.


RESULTS
Microbiological tests detected 57% of extended-spectrum beta-lactamase-producing isolates. blaTEM, blasHv and blacTX-M genes were detected by PCR in 82% of the isolates. 7 out of 9 isolates carrying group 1 blacTX-M genes were in the resistant or intermediate range for cefepime. These isolates produced cefotaxime-resistant transconjugants.


CONCLUSIONS
A relationship was found between resistance to cefepime and the presence of cefotaximases in E. cloacae. blacTx-M genes were present in 32% of the isolates, indicating an significant spread in the hospitals being studied. The facility of these genes' transfer between other species and Enterobacteria genera becomes an important reason for detecting them and controlling their spread in hospital settings. These results suggest a cautious use of cefepime for treating infection caused by E. cloacae strains which might produce CTX-M enzymes.
González-Mejía
Elsa B
EB
Instituto de Biotecnología, Universidad Nacional de Colombia. ebgonzalezm@unal.edu.co
Valenzuela
Emilia M
EM
Mantilla-Anaya
José R
JR
Leal-Castro
Aura L
AL
Saavedra-Trujillo
Carlos H
CH
Eslava-Schmalbach
Javier
J
Sierra-Rodriguez
Pedro
P
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000077723:Cefepime; D002511:Cephalosporins / Q000494:pharmacology*; D003105:Colombia; D003428:Cross Infection / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D016972:Enterobacter cloacae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D005798:Genes, Bacterial; D006801:Humans; D008828:Microbiological Techniques; D016133:Polymerase Chain Reaction; D001618:beta-Lactamases / Q000235:genetics
D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D000077723:Cefepime; C071167:beta-lactamase CTX-2; D001618:beta-Lactamases