Resistance against broad-spectrum beta-lactams among uropathogens in children.

The aim of this study was to investigate the prevalence trends and risk factors for urinary tract infection (UTI) caused by Enterobacteriaceae resistant to broad-spectrum beta-lactams in children. All Enterobacteriaceae uropathogens from children <15 years during the 11-year period 1997-2007 were included, and risk factors were evaluated. Of 523 Enterobacteriaceae isolated from 473 children, 30 (5.73%) were phenotypically resistant to broad-spectrum beta-lactams (18 Escherichia coli, ten Klebsiella spp, one Enterobacter spp, and one Citrobacter spp). The prevalence of resistance increased during the study period (p = 0.031). Resistance to cefoxitin was common (26/30), pointing to AmpC enzyme expression, and 2/30 isolates were resistant to carbapenems. Resistant Enterobacteriaceae were often community acquired (22/30, 73.3%) and related to male gender (p < 0.05), urinary tract abnormalities (p < 0.05), prophylactic antibiotics (p < 0.0001), longer hospitalization (p < 0.001), and UTI recurrences (p < 0.001). Co-resistance was more likely for cotrimoxazole, gentamicin, and ciprofloxacin (p < 0.0001). In conclusion, our study points to increasing prevalence of Enterobacteriaceae uropathogens resistant to broad-spectrum beta-lactams in the community setting, which limits the utility of first-line antibiotics and questions the validity of using prophylaxis after a first UTI episode.