Antibiotic resistance pattern of Escherichia coli isolated from patients with urinary tract infection in Sarab, Iran

Urinary tract infection (UTI) is one of the most prevalent infectious diseases and Escherichia coli is its common cause. Therapy for these infections is usually begun before results of microbiological tests are known. The rationale for this approach is based on the highly predictable spectrum of etiologic agents causing UTI and their antimicrobialresistance patterns. Escherichia coli remains the predominant uropathogenic (80%) isolated in acute community-acquired uncomplicated infections. Recent advances in molecular biology may facilitate the identification of new etiologic agents for UTI. The need for accurate and updated population surveillance data is apparent, particularly in light of concerns regarding antimicrobial resistance. This information will directly affect the selection of empiric therapy for UTI.The aim of this study was to assess the resistance patterns of E. coli in urinary tract infections and to determine the susceptibility of E. coli to commonly used antimicrobials and also to evaluate the options for empirical treatment of UTI. Our study was carried out in the Imam Khomeini Teaching Hospital of Sarab Medical Sciences Faculty. Sample collection was done between March 2017 and November 2017; antimicrobial susceptibility tests were done by disk diffusion method. The diagnosis of UTI WAS based on a quantitative urine culture yielding greater than 100,000 colony-forming units per milliliter (105 CFU/ml) of urine. Results were analyzed after using ten commonly used antibiotics for susceptibility test according to CLSI protocol. E. coli grew in 115 (115/141) urine samples. Imipenem, ofloxacin, ciprofloxacin were the most effective antibiotics (89.3%, 88.1%, and 84.8% respectively). Maximum resistance was detected for cotrimoxazole, cefixime, cefotaxime,and ceftriaxone. Knowledge of local susceptibility patterns is important for the selection of appropriate empirical therapy for UTI. In conclusion, data from local laboratories exaggerate the fluoroquinolone resistance problems among E. coli urine isolates from general practice. Imipenem, ofloxacin,and ciprofloxacin should be used in empirical therapy of UTI. For optimal interpretation of cumulative susceptibility data in the primary healthcare setting, it is necessary to take into account the type of UTI (uncomplicated vs. complicated), as well as the sex and age of each patient.

کلیدواژه ها:

Urinary tract infection ، Escherichia coli ، Antibiotic susceptibility ، Disk diffusion