Antimicrobial Susceptibility Patterns of lt;i gt;Escherichia coli lt;/i gt; Isolates from Hospitalized Patients with Different Infections in Isfahan, Iran: Impact on Empiric Antibiotic Therapy in Associated Infections

Background: Escherichia coliis an important cause of urinary tract, bloodstream, and surgical site infections.Objectives: We investigated the organism s antibiotic susceptibility in hospitalized patients under different clinical conditions. Methods: This prospective study was conducted in three referral hospitals located in Isfahan, Iran. Different clinical samples were tested using standard routine microbiological methods to identify E. coli strains and determine their antibiotic susceptibility patterns by the disk diffusion method according to CLSI recommendations. After conducting a clinical investigation, contaminated samples were excluded, and the hospital or community source and infection site were identified. Data on antibiotic susceptibility testing were extracted using WHONET software. Data analysis was then conducted using SPSS Statistics version 18.0. Results: Of 1248 E. coliisolates, 71.9% were from urine, 15.1% from blood, and 7.8% from skin and soft tissue samples. High susceptibility was observed to Imipenem (98%), Meropenem (98.0%), and Amikacin (94.6%); intermediate sensitivity to Gentamicin (68.6%) and Cefepime (51.9%); and low susceptibility to Ceftazidime (46.8%), Ceftriaxone (41.3%), Ciprofloxacin (39.5%), Cefotaxime (39.3%), and Trimethoprim-sulfamethoxazole (32.4%). Conclusions: Antibiotics, including Imipenem, Meropenem, or Amikacin, would be beneficial in the empiric therapy of severe infections where E. coliis the main cause.