Comparison of the Common Adhesin Coding Operons Distribution in Uropathogenic and Phylogenetic Group B2 and A Escherichia coli Isolates

Prevalence of some virulence factors and genotyping of hospital-acquired uropathogenic Escherichia coli isolates recovered from cancer patients

OBJECTIVES

This study aimed to determine the prevalence of virulence factors among uropathogenic Escherichia coli (UPEC) isolates from cancer patients and to investigate their genetic diversity using ERIC-PCR.

METHODS

A total of 42 E. coli were recovered from urine samples from cancer patients admitted to Assiut University Hospital. PCR was used to detect the presence of three virulence genes (papC, iutA and cnf1). Genetic diversity of the isolates was determined using the ERIC-PCR fingerprinting method, and amplified products were separated by agarose gel electrophoresis. Gel electrophoresis banding patterns were used for dendrogram generation using NTSYSpc software.

RESULTS

Among the 42 UPEC isolates, papC was the most common virulence gene (55% of isolates), followed by iutA (38%) and cnf1 (2%). ERIC-PCR successfully produced multiple amplicons (range 2-11 bands) in each strain, with molecular weights ranging from 285 to 3000 bp. Some UPEC isolates had identical ERIC-PCR profiles (identical banding patterns), whilst 22 UPEC isolates had different ERIC-PCR profiles. The phylogenetic dendrogram of ERIC-PCR showed that the 42 isolates can be differentiated into three major clusters (I, II and III), with cluster I representing 76% of isolates, cluster II representing 19% and cluster III representing 5%.

CONCLUSIONS

The results of this study suggest that both papC and iutA genes may have an important role in the pathogenesis of overt urinary tract infection. Dendrogram analysis of the ERIC-PCR profiles revealed that all UPEC isolates were assigned into three main clusters, indicating the spread of distinct clonal groups that are responsible for hospital-acquired infections.