Antibiotic susceptibility patterns of isolates from children with urinary tract infection in Isfahan, Iran: Impact on empirical treatment

•E. coli was the most common cause of UTI among 364 isolates.•More than 50% of isolates were resistant to cotrimoxazole and cefalexin.•Only 53% of pathogens were susceptible to cefotaxime.•Susceptibility to nitrofurantoin, ciprofloxacin and imipenem was >70%.•Resistance to imipenem, cefotaxime and cefalexin was higher in recurrent UTI cases. The aim of this study was to identify the antibiotic susceptibility of bacteria causing urinary tract infections (UTIs) in children in Isfahan, Iran. Retrospective and prospective analyses were conducted on isolates from children with UTIs in a referral teaching hospital of Isfahan during 2013–2015. Findings were compared between first episode versus recurrent, nosocomial versus community-acquired, previous antibiotic use versus no previous antibiotic use, and febrile versus afebrile cases. Among 364 patients, 68.1% had no previous UTI, 19.7% has received antibiotics prior to infection and 96.2% were infected outside the hospital. Escherichia coli was the leading cause of UTI (68.1%), followed by Enterobacter (9.3%), Klebsiella (8.8%) and other bacteria (13.7%). Most isolates were relatively highly susceptible to imipenem (79.2%), ciprofloxacin (78.0%) and nitrofurantoin (70.8%), whereas sensitivity to cefotaxime (53%), cefalexin (39.8%) and trimethoprim/sulfamethoxazole (SXT) (26.1%) was low. Resistance to imipenem, cefotaxime and cefalexin was more prevalent in recurrent cases as well as in patients consuming antibiotics prior to UTI. Resistance of nosocomial cases to nitrofurantoin and cefotaxime was higher. In addition, afebrile patients had isolates that were more resistant to imipenem, ciprofloxacin and cefotaxime. Significant cross-resistance was found between most of the studied antibiotics. Urinary pathogens showed low susceptibility to cefalexin, SXT and cefotaxime and high susceptibility to imipenem, ciprofloxacin and nitrofurantoin. Therefore, use of imipenem and ciprofloxacin should be considered in hospitalised children with severe or complicated disease. In addition, nitrofurantoin is a good option in afebrile cases and for UTI chemoprophylaxis in this area.