Distribution of the usp Gene in Uropathogenic Escherichia coli Isolated from Companion Animals and Correlation with Serotypes and Size-Variations of the Pathogenicity Island

Uncomplicated urinary tract infection (UTI) caused by uropathogenic Escherichia coli (UPEC) is a serious problem not only among humans but also in companion animals such as dogs and cats. The uropathogenic specific protein gene (usp) is preferentially distributed in UPEC isolates from dogs and cats compared with the distribution of usp in E. coli strains from feces of healthy dogs and cats and this pattern of distribution resembles that observed in human UPEC strains. The UPEC strains from companion animals share common O serotypes like O1, O2, O4, O6, O16, O18, O22, O25 and O75 as those reported for human UPEC. The size variation of the pathogenicity island that includes usp in UPEC from dogs and cats was almost similar to those seen in human UPEC. We propose that dogs and cats are the alternative reservoirs for UPEC strains that are associated with human UTI.