Escherichia albertii, a newly emerging enteric pathogen with poorly defined properties

Escherichia albertii is a newly emerging enteric pathogen that has been associated with sporadic infections among humans and birds. Selected coliform isolates were screened for allelic variation in 2 housekeeping genes (lysP and mdh) specific for E. albertii. The 48 strains that were identified as E. albertii were tested for 15 virulence markers and biochemical and serogical properties. All E. albertii strains were non-motile, fermented D-glucose (with gas), D-mannitol, and D-mannose, but failed to ferment lactose and other sugars. Variable positive reactions were noted for other tests. Most strains were rough or failed to agglutinate with Shigella boydii 13 antisera and E. coli antisera with few exceptions. All strains were positive for the eaeA gene, and variable numbers were positive for the cdtB, phoE, ehxA, and stx2f genes. Results illustrate the variability extent within this lineage and highlight the importance of accurately distinguishing it within the genus Escherichia and including information within commercial databases to improve their identification.