Extended-Spectrum β-Lactamase-Producing Escherichia coli and Virulence Genes in Pediatric Patients with Health-Care...

Healthcare-associated urinary tract infection (UTI) represents a significant health problem, especially in infants and young children. The most common pathogen associated with this infection is Escherichia coli (E. coli).

The present study aimed to detect the frequency of virulence genes among clinical isolates of E. coli isolated from healthcare-associated urinary tract infections in children and the correlation between these virulence genes and the presence of the bla_CTX gene.

The study included one hundred clinical isolates of E. coli isolated from healthcareassociated urinary tract infections in children in intensive care units. The isolates were subjected to antibiotics sensitivity by disc diffusion method and detection of extended-spectrum beta-lactamase by double disc diffusion method. In addition, multiplex polymerase chain reaction (PCR) was used to detect some virulence genes, and PCR was used to detect the bla_CTX-M gene.

E. coli producing ESBL by double discs method was identified in 74 isolates. bla_CTX-M gene detection by PCR was identified among 38 isolates representing 51.4% of ESBL-producing E. coli. There was a significant association between ESBL and bla_CTX-M Gene, P = 0.0001. The frequency of the studied virulence genes by multiplex PCR in the isolated E. coli was 66% for the Fim gene, 75% for the Aer gene, 68% for the FliC gene, 53% for each of IucD gene and Usp gene, 40% for pap gene, 35% for each of AFA and ironN genes and 17% for sfa gene. None of the isolated E. coli had the Cdt gene. There was a significant association between the presence of the FimH gene (P = 0.0001), Pap gene (P = 0.05), sfa (P = 0.026), Afa gene (P = 0.018), and aer gene (P = 0.035) and the presence of the bla_CTX-M gene in the isolated E. coli.

The present study highlights the presence of virulence genes and bla_CTX-M gene in uropathogenic E. coli isolated from pediatric patients with healthcare-associated urinary tract infections. There was an association between the bla_CTX-M gene and virulence genes FimH, pap, sfa, Afa, and aer. Various distributions of the studied genes with a high frequency of fimbria are flic genes. Moreover, the ESBL had high frequency in E. coli with the presence of bla_CTX-M in about one-third of the isolates.