Study examines aspects of first urinary tract infection

A prospective study described the uropathogen frequencies and antimicrobial resistance rates of first UTI in 209 children (median age, 10 months) who were diagnosed at the ED of a Belgian hospital. The children were followed for 1 year.

Escherichia coli was by far the most common pathogen, accounting for 91% of UTIs. Fifty-eight percent of the E coli isolated were resistant to ampicillin, as were 36% to trimethoprim/sulfamethoxazole.

Other causative pathogens were Klebsiella pneumoniae, Proteus mirabilis, Enterobacter spp, and Streptococcus faecalis. Nitrofurantoin, temocillin, and amikacin were the most active agents against E coli, followed by cephalosporins of second and third generation, gentamicin, ciprofloxacin, and amoxicillin/clavulanic acid. Amikacin and temocillin also were the most active agents against K pneumoniae and P mirabilis.

Commentary

In this study, 25% of patients had urinary reflux on voiding cystourethrogram (VCUG), but 85% of the reflux was considered low grade (grades 1 to 3) and probably not worthy of prophylaxis or other interventions. In the 8 children with grade 4 or 5 reflux, 7 (88%) had an abnormal renal ultrasound. The overall sensitivity of ultrasound in detecting renal abnormalities, including high-grade but excluding low-grade reflux, was 97%. The number of patients with high-grade reflux in this study is small, so this article may not stand on its own, but along with other studies published and ongoing, it may allow us to move away from VCUG in routine evaluation of febrile UTIs. -Michael Burke, MD