Antimicrobial resistance patterns of urinary tract pathogens and rationale for empirical therapy in Turkish children for the years 2000–2006

In patients with suspected urinary tract infection (UTI), antibiotic treatment is usually started empirically, before urine culture results are available. Unfortunately, antibiotic resistance has become an increasingly pressing clinical issue in many countries. The objective of this study was to assess the changing susceptibility of urinary pathogens to commonly used antimicrobials in a six-year period to evaluate the options for empirical antibiotic therapy in children with community acquired UTI.

A retrospective analysis of data from all pediatric urine samples processed at Fatih University Medical School microbiology laboratory was undertaken for a period of six years (January 2000–December 2006).

A total of 767 urinary pathogens were isolated from 767 episodes of UTI in 698 patients. The most common causative agent was Escherichia coli (E. coli) followed by Klebsiella spp. and others. In 2000 almost 60% of the E. coli isolates were susceptible to ampicillin (AMP), more than 40% to Co-trimoxazole (SXT), more than 80% to gentamicin (GN), more than 90% to cefuroxime (CXM) and amikacin (AN), and more than 60% to piperacillin (PIP). By 2006 more than 70% were resistant to AMP and more than 50% were resistant to PIP. In 2000 CIP (2.7% resistant isolates) and CXM (3.4% resistant isolates) were the most active agents against Klebsiella spp.; and none of the isolates was found to be resistant to imipenem (IMP). In 2006 GN (2.7% resistant isolates), CIP (3.5% resistant isolates), CXM (2.7% resistant isolates), and AN (8.9% resistant isolates) were the most active agents against these species and still no resistance to IMP was found. For E. Coli the increase in resistance to AMP, CTX, IMP, and PIP was statistically significant (P < 0.05). For Klebsiella spp. the increase in resistance to AMP and CXM was statistically significant (P < 0.05).

Empirical antibiotic selection should be based on knowledge of the local prevalence of bacterial organisms and antibiotic sensitivities, because resistance patterns may vary in different regions.