An abbreviated MLVA identifies Escherichia coli ST131 as the major extended-spectrum [beta]-lactamase-producing lineage in the Copenhagen area

• Published in: European journal of clinical microbiology & infectious diseases 2013-03, Vol.32 (3), p.431
• Main Authors: Nielsen, J B, Albayati, A, Jørgensen, R L, Hansen, K H, Lundgren, B, Schønning, K
• Format: Article
• Language: English
• Subjects: Capillary electrophoresis; Cloning; E coli; Electrophoresis; Epidemiology; Health care; Health surveillance; Infections; Patient assessment; Polymerase chain reaction
• ISSN: 0934-9723; 1435-4373
• DOI: 10.1007/s10096-012-1764-x

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 [beta]-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.[PUBLICATION ABSTRACT]