title: The prevalence of ESBL-producing E. coli and Klebsiella strains in the Copenhagen area of Denmark.
abstract: The main purpose of the study was to investigate the frequency of ESBL-producing E. coli and Klebsiella strains in the Greater Copenhagen area. Four collections of strains were investigated: A) 380 consecutive E. coli and Klebsiella isolates primarily from urine, B) 200 gentamicin-resistant E. coli and Klebsiella isolates primarily from urine, C) 210 consecutive E. coli isolates from blood cultures, and D) 68 cefuroxime-resistant E. coli and Klebsiella isolates primarily from urine. Only one strain per patient was included. Strains with a zone diameter for cefpodoxime <or=23 mm were tested by a phenotypic confirmatory test for ESBL production and all screening test-positive strains were examined with PCR and nucleotide sequencing in order to detect the following ESBL genes: ctx-m, shv, tem and oxa. Strains resistant to cefoxitin were further examined with cefotetan+/-boronic acid in order to detect AmpC. An ESBL gene was detected in 3/3 confirmatory test-positive isolates from collection A, in 14/17 from collection B, and in 41/48 from collection D. The distribution of isolates with the ESBL and/or AmpC enzymes was as follows: CTX-M (n=41), SHV (n=14), AmpC (n=9), CTX-M and AmpC (n=2), SHV and AmpC (n=1). In conclusion, the frequency of ESBL-producing E. coli and Klebsiella isolates was low in the Copenhagen area of Denmark (0.8 %). The most common ESBL genes found in our study were ctx-m and shv genes.
authors.affiliation: Department of Clinical Microbiology, Herlev University Hospital, Herlev, Denmark. alf@ssi.dk
authors.forename: Anne
authors.initials: A
authors.lastname: Kjerulf
authors.forename: Dennis S
authors.initials: DS
authors.lastname: Hansen
authors.forename: Dorthe
authors.initials: D
authors.lastname: Sandvang
authors.forename: Frank
authors.initials: F
authors.lastname: Hansen
authors.forename: Niels
authors.initials: N
authors.lastname: Frimodt-Møller
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D003718:Denmark / Q000453:epidemiology; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D007709:Klebsiella / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D007710:Klebsiella Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D012189:Retrospective Studies; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C048795:AmpC beta-lactamases; D001618:beta-Lactamases