Virulence characteristics and antimicrobial susceptibility of uropathogenic Escherichia coli strains

Abstract

Eight virulence factors associated with uropathogenic Escherichia coli (UPEC) were investigated in 204 clinical isolates of E. coli recovered from urine cultures at counts ≥10(5). The bacteria were classified into two groups according to the number of leukocytes in urine samples from which they were isolated: group I ≤8 leukocytes/hpf, 104 strains; group II >8 leukocytes/hpf, 100 strains. Two multiplex PCR systems were used to detect genes encoding adhesin P (pap), adhesin S (sfa), afimbrial adhesin I (afa), siderophore aerobactin (aer), alpha-hemolysin (hly), cytotoxic necrotizing factor type 1 (cnf1), and traT associated with serum resistance. The PAI marker for the virulence island identified in strains CFT072 and CVD432, a marker of enteroaggregative E. coli, was also investigated using PCR. The susceptibility profile of E. coli strains was determined by disk diffusion method. Ninety percent UPEC showed at least one of the virulence genes, the prevalence being traT (76%), aer (41%), PAI (32%), sfa (26%), pap (25%), cnf1 (18%), afa (6%), and hly (5%). There was no significant difference in the distribution of virulence genes between groups I and II. A significantly higher degree of virulence was detected in UPEC group II. The CVD432 gene was not detected in any of the UPECs. Fifty-nine percent of the strains were resistant to at least one of the antimicrobials that we tested; the most common being resistance to ampicillin (51%) and trimethoprim-sulfamethoxazole (44%).

Antibiogram and characterization of resistance markers among Escherichia coli Isolates from urinary tract infections

“…Moreover, antimicrobial resistance to various classes of antimicrobials continues to be a major health problem in different parts of the world [17][18][19][20], including India [21][22][23][24], posing a therapeutic challenge for health authorities. Antimicrobial resistance among UPEC shows considerable variations during different time periods and in different areas.…”

Antibacterial Activity of Some Seaweed Extracts against Multidrug Resistant Urinary Tract Bacteria and Analysis of their Virulence Genes

“…UTI bacterial strains have various types of virulence factors such as adhesions, hemolysin, urease enzyme, toxins and iron uptake systems that facilitate colonization and persistence of the bacteria in the urinary tract (Oliveira et al, 2011) and support their resistance system and pathogenicity to the regularly used synthetic drugs.…”

Detection of Several Virulence Properties, Antibiotic Resistance and Phylogenetic Relationship in E. Coli Isolates Originated from Cow Mastitis

“…Following pre-denaturation at 94°C for 60 seconds, the amplifi cation conditions included 30 cycles of denaturation at 94°C for 60 seconds, primer annealing at 63°C for 30 seconds, and extension at 70°C for 90 seconds. The fi nal extension step was 5 minutes at 70°C [11].…”