title: An abbreviated MLVA identifies Escherichia coli ST131 as the major extended-spectrum β-lactamase-producing lineage in the Copenhagen area.
abstract: Rapid bacterial typing is a valuable and necessary tool in the prevention and detection of outbreaks. The purpose of this study was to adapt a multilocus variable number of tandem repeats analysis (MLVA) for analysis on a benchtop capillary electrophoresis instrument and compare the modified assay with multilocus sequence typing (MLST) for typing cefpodoxime-resistant Escherichia coli (E. coli). Further, we identified the causative resistance mechanisms and epidemiological type of infection for isolates producing extended-spectrum β-lactamases (ESBLs). A collection of E. coli resistant to cefpodoxime was typed by MLST and a modified MLVA assay using a benchtop capillary electrophoresis instrument. Resistance mechanisms were identified by polymerase chain reaction (PCR) and sequencing. Patient history was examined to establish the epidemiological type of infection for ESBL-producing E. coli. MLVA yielded typing results homologous with MLST and it correctly identified E. coli sequence type (ST) 131 that was accounting for 45 % of all ESBL-producing isolates in the sample collection. The majority (76.7 %) of ESBL-producing isolates was healthcare-related and only 23.3 % of the ESBL-producing isolates were community-onset infections (COI), regardless of the ST. Patients with COI were significantly more often of female gender and younger age compared to healthcare-associated infections (HCAI) and hospital-onset infections (HOI). In conclusion, the modified MLVA is a useful tool for the rapid typing of E. coli and it identified ST131 as the predominating ESBL-producing lineage in Copenhagen. Healthcare-related infections were the predominant infection setting of ESBL-producing E. coli and the demographic characteristics differed between patients with COI and healthcare-related infections.
authors.affiliation: Department of Clinical Microbiology 445, Hvidovre Hospital, Kettegaard Alle 30, 2650 Hvidovre, Denmark. jesper.boye.nielsen@regionh.dk
authors.forename: J B
authors.initials: JB
authors.lastname: Nielsen
authors.forename: A
authors.initials: A
authors.lastname: Albayati
authors.forename: R L
authors.initials: RL
authors.lastname: Jørgensen
authors.forename: K H
authors.initials: KH
authors.lastname: Hansen
authors.forename: B
authors.initials: B
authors.lastname: Lundgren
authors.forename: K
authors.initials: K
authors.lastname: Schønning
mesh_terms: D000328:Adult; D000368:Aged; D004269:DNA, Bacterial / Q000235:genetics; D003718:Denmark / Q000453:epidemiology; D019075:Electrophoresis, Capillary / Q000379:methods; D004926:Escherichia coli / Q000145:classification* / Q000201:enzymology* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D018598:Minisatellite Repeats; D058889:Molecular Typing / Q000379:methods*; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D004269:DNA, Bacterial; D001618:beta-Lactamases