Emerging Multidrug-Resistant Hybrid Pathotype Shiga Toxin–Producing Escherichia coli O80 and Related Strains of Clonal Complex 165, Europe

Abstract

Enterohemorrhagic Escherichia coli serogroup O80, involved in hemolytic uremic syndrome associated with extraintestinal infections, has emerged in France. We obtained circularized sequences of the O80 strain RDEx444, responsible for hemolytic uremic syndrome with bacteremia, and noncircularized sequences of 35 O80 E. coli isolated from humans and animals in Europe with or without Shiga toxin genes. RDEx444 harbored a mosaic plasmid, pR444_A, combining extraintestinal virulence determinants and a multidrug resistance–encoding island. All strains belonged to clonal complex 165, which is distantly related to other major enterohemorrhagic E. coli lineages. All stx-positive strains contained eae-ξ, ehxA, and genes characteristic of pR444_A. Among stx-negative strains, 1 produced extended-spectrum β-lactamase, 1 harbored the colistin-resistance gene mcr1, and 2 possessed genes characteristic of enteropathogenic and pyelonephritis E. coli. Because O80–clonal complex 165 strains can integrate intestinal and extraintestinal virulence factors in combination with diverse drug-resistance genes, they constitute dangerous and versatile multidrug-resistant pathogens.

Keywords

• Escherichia coli
• Shiga toxin-producing E. coli
• STEC
• enterohemorrhagic E. coli
• hybrid pathotype
• extra-intestinal virulence