Virulence Determinants among Extended-Spectrum B-Lactamases Producers of Uropathogenic Escherichia Coli Isolates in Zagagig University Hospitals, Egypt

Abstract

Background: Uropathogenic E. coli (UPEC), the major causative agent of urinary tract infections (UTI) worldwide have variant virulent mechanisms. UPEC resistance to commonly used antibiotics represents a major health problem all over the world. The empiric antibacterial therapy of the infections should be based on a local experience of the susceptibility and the resistance profile. Our objectives are to detect the presence of and possible relation between virulence genes and ESBL production in E. coli strains isolated from patients with UTI in Zagazig, Egypt. Methodology: 75 E. coli strains isolated from patients with UTI were screened for virulence genes: fimH (type 1 fimbriae), pap (pyelonephritis-associated pili), sfa/foc (S and F1C fimbriae), afa (afimbrial adhesins), hly (hemolysin), cnf1 (cytotoxic necrotizing factor), aer (aerobactin), traT (transfer gene foe serum resistance) by polymerase chain reaction (PCR) and for antimicrobial resistance by disc diffusion method according to CLSI criteria along with extended spectrum B lactamases (ESBL) detection by double disc synergy (DDS) method. Results: The fimH gene was the most common virulence gene and was detected in 85.3% of the UTI isolates. The trat gene was present in 69.3% (52/75) and the pap gene in 52% of isolates. The aer gene was detected in 40% while the sfa gene and afa gene were shown in 29.3% and 21.3% of isolates respectively. Among the genes coding for toxin, hly was found in 9.3%, while cnf was present in only 8% of isolates. Eight strains genes lacked any tested virulence markers accounting (10.7%). Out of 75 strains, 41 (54.7%) were ESBL producers. Statistically significant relationships were found between fimH, tratT and pap with ESBL production (p values of <0.05, <0.0001 & <0.0001 respectively). Conclusions : There was a significant association between some virulence determinants of UPEC and ESBL production, these determinants may contribute to a better medical intervention. Also we need the used treatment regimens to be revised to reach better therapeutic effects .