Detection of Virulence Markers in Uropathogenic Escherichia coli, their Serotypes and Antibiotic Sensitivity Patterns

Escherichia coli remains the predominant uropathogen (70-90%) isolated from acute community acquired uncomplicated infections. E. coli present in the gastrointestinal tract, as commensals provide the pool for initiation of urinary tract infection. Subsets of fecal E. coli with specific virulence factors that can colonize the periurethral area, enter the urinary tract and cause disease are known as uropathogenic E. coli (UPEC). The most important amongst the virulence markers, are adhesins like type 1 fimbriae, P fimbriae. Other factors associated with UPEC include production of Hemolysin and cell surface hydrophobicity. 210 isolates of E. coli from urinary tract infection were screened for virulence markers Hemolysin, Surface Hydrophobicity and Mannose resistant & Mannose sensitive Haemagglutination. Monovalent E. coli antisera belonging to serogroups 01, 06, 08, 015, 018, 020, 025 (Denka Seikien, Tokyo, Japan) were used for serotyping. All the isolates were also studied for an antibiotic susceptibility pattern using Kirby Bauer disk diffusion method. Among 210 isolates, 35.71% were Hemolytic, 29.04% were Hydrophobic, 28% showed Mannose-resistant Haemagglutination and 11% showed Mannose-sensitive Haemagglutination. Multiple (all) virulence factors tested were observed in 29 (24.78%) of isolates. It was observed that 26.8% (15/56) isolates belonged to the serogroup O6, followed by O8 (23.2%). Isolated E. coli was found to be most sensitive to Nitrofurantoin (85.71%), followed by Gentamicin (78.09%) and least sensitive to Ampicillin. The present study showed the expression of virulence factors and multiple drug resistance in E. coli isolated from urinary tract infection. K ey wo rd s