Multi-Locus Variable Number of Tandem Repeat Analysis for Rapid and Accurate Typing of Virulent Multidrug Resistant Escherichia coli Clones

One hundred E. coli isolates from Norway(n = 37), Sweden (n = 24), UK(n = 20) and Spain (n = 19), producingCTX-M-type - (n = 84), or SHV-12(n = 4) extended spectrum β-lactamases, or the plasmidmediated AmpC, CMY-2 (n = 12), were typed using multi-locussequence typing (MLST) and multi-locus variable number of tandem repeat analysis(MLVA). Isolates clustered into 33 Sequence Types (STs) and 14 Sequence TypeComplexes (STCs), and 58 MLVA-Types (MTs) and 25 different MLVA-Type Complexes(MTCs). A strong agreement between the MLST profile and MLVA typing results wasobserved, in which all ST131-isolates (n = 39) and most ofthe STC-648 (n = 10), STC-38 (n = 9),STC-10 (n = 9), STC-405 (n = 8) andSTC-23 (n = 6) isolates were clustered distinctly intoMTC-29, -36, -20, -14, -10 and -39, respectively. MLVA is a rapid and accuratetool for genotyping isolates of globally disseminated virulent multidrugresistant E. coli lineages, including ST131.