Abstract

Resistance rate of uropathogenic Escherichia coli against different antimicrobial agents is currently a matter of concern. The antimicrobial susceptibility patterns of 100 uropathogenicE. coli isolated from Saudi Arabia was conducted by broth microdilution method. The resistance genes for chloramphenicol, tetracycline, sulphamethoxazole and streptomycinwere checked by polymerase chain reaction (PCR). The overall resistance for sulphamethoxazole and streptomycin was 100%. However, the resistance rates for ampicillin, tetracycline, chloramphenicol, trimethoprim, sulphamethoxazole/trimethoprim, amoxicillin/clavulanate, gentamicin, amikacin, ciprofloxacin, cefotaxime, ceftazidime, aztreonam, cefepime and nitrofurantoin were 90, 85, 83, 70, 62, 60, 42, 29, 24, 22, 21, 20, 17 and 5% respectively. All isolates were sensitive to imipenem, tigecycline and cefoxitin. The prevalence of the antibiotic resistance genes for strA + strB, tet(B), catI, sul2, aadA, sul1, cmlA, tet(D) and sul3 were 100, 94.5, 89.5, 86.36, 77.3, 68.18, 45, 13.6 and 5.5% respectively. The catI, tet(B), and sul2 genes were the most prevalent resistance genes. The prevalence of class 1 integrase was 95.45%. The present study gives baseline data on molecular basis of antimicrobial resistance in uropathogenic E. coli from Riyadh. In the majority of cases, resistance to a given antimicrobial was caused by more than single gene.

Keywords: Escherichia coli, urinary tract infections, antimicrobial resistances, Saudi Arabia.