Antibiotic Resistance and Virulence Factors Properties of Escherichia coli K۱ Recto-vaginal Colonized Pregnant Women in Iran

Background and Aim : Neonatal invasive infections caused by E. coli K۱ are still major health problems and effective preventive strategies at the maternal level can be a concern. The aim of this study was to determine the prevalence of recto-vaginal colonization, related risk factors, virulence factors and antibiotic resistance properties of E. coli K۱ among pregnant women.Methods : In this cross-sectional study vaginal and rectal swabs were collected among ۴۰۰ pregnant women. The identification of E. coli isolates was performed by microbiological tests. A PCR assay was used to identify the E. coli K۱ strains. The antimicrobial susceptibility patterns were determined by the Kirby-Bauer disk diffusion. Two duplex PCR assays were developed separately to detect virulence determinants (fimH, hlyF, ibeA and iucC) in the E. coli strains. Results : The vaginal and rectal maternal E. coli K۱ colonization rates were reported ۳.۷% and ۱۹.۲۵%, respectively. There is no significant association between demographic-obstetric factors and vaginal E. coli colonization. The most effective antibiotics against E. coli K۱ strains were Imipenem, Gentamycin, Ciprofloxacin and Ceftazidime. In our study the E. coli K۱ strains were significantly more likely to possess the fimH (۹۰.۹ vs. ۶۰.۷%) and iucC (۹۰.۹ vs. ۵۳.۶%) than E. coli Non-K۱ strains.Conclusion : This study demonstrates that E. coli K۱ seems to be more virulent than Non-K۱ strains. Our findings highlight the importance of screening pregnant women for vaginal colonization by E. coli K۱ and the appropriate antibiotic prophylaxis for the prevention of early onset E. coli -neonatal infection and co-morbidity.

Keywords:

Escherichia coli K۱ , Pregnant women , Antibiotic resistance , Risk factors , Polymerase chain reaction , Virulence factors.