Virulence factors and antibiotic resistance patterns of uropathogenic Escherichia coli

Urinary tract infections (UTIs) are one of the most common infections in humans and the commonest cause is uropathogenic Escherichia coli (UPEC). UPEC possess various virulence factors which enable them to survive and grow in urine and other extra-intestinal environments. Similarly, avian pathogenic E. coli (APEC) are known for their ability to cause extra-intestinal diseases in birds. Since APEC and UPEC may encounter similar challenges when establishing infection in these locations, they may share a similar content of virulence genes and capacity to cause disease. In this study, 40 UPEC isolates were obtained from patients with suspected UTIs. Multiplex polymerase chain reaction (PCR) was then used to screen the 40 UPEC isolates for 12 virulence genes usually associated with APEC isolates. The iutA (35%), fimH (32.5%), vat (17.5%), sitA (17.5%), sitD (15%), hlyF (12.5%), pstB (10%) and frz (7.5%) genes were detected. None of the isolates had the kpsM, ompT, uvrY and sopB genes. Antibiotic resistance patterns were also determined for all 40 isolates. A high resistance to ampicillin (90%) and tetracycline (75%) accompanied by a high sensitivity to gentamycin (82.5%) and nitrofurantoin (62.5%) was observed. Eleven multi-drug resistance patterns were observed in 65% (26/40) of the isolates. The studied UPEC isolates were shown to possess APEC associated virulence genes at low percentage frequencies suggesting a slight overlap in virulence genotypes. Antibiotic resistance patterns suggest surveillance programs to monitor drug resistance should be put in place. Key words: Uropathogenic Escherichia coli, virulence genes, multiplex polymerase chain reaction (PCR), antibiotic resistance, Zimbabwe.