Screening ultrasound after a first febrile UTI is not cost-effective

Although the American Academy of Pediatrics (AAP) recommends routine screening renal bladder ultrasound (RBUS) after a first febrile urinary tract infection (UTI), a comparison of this strategy with routine RBUS after a second UTI found that the AAP approach does not meet cost-effectiveness guidelines.

Investigators developed a decision analytic model to simulate a group of 2- to 24-month-old children who were followed for 5 years after a first febrile UTI. The model predicted incidence of recurrent UTIs in the context of vesicoureteral reflux and genitourinary anomalies and whether the child was treated. It compared estimated recurrent UTI rates and quality-of-life measures among children receiving routine RBUS after a first febrile UTI (intervention group) versus those receiving routine RBUS after the second UTI (control group).

The accuracy (true positives and true negatives) of RBUS for detecting an abnormality after a first febrile UTI was 64.5%. The sensitivity and specificity of detecting any abnormality were 29.2% and 84.0%, respectively. Among patients in the intervention group, the recurrent UTI rate was 19.9% compared with 21.0% in the control group, meaning that 91 patients would need to be screened, at a cost of $11,200, to prevent 1 recurrent UTI.

In the intervention group, 20.6% of children would receive unnecessary voiding cystourethrograms (VCUGs) compared with 12.2% in the control group. The simulation also showed that compared with RBUS after a second UTI, routine RBUS after a first UTI not only raises costs but results in a lower quality of life (Gaither TW, et al. J Pediatr. 2020;216:73-81).

Thoughts from Dr. Farber

Years ago, the standard of care (without supportive evidence) for a first febrile UTI was RBUS and voiding cystourethrogram (VCUG). If the latter was positive, prophylactic antibiotics were started, and a VCUG was obtained on siblings aged younger than 10 years. As evidence accumulated, VCUG is now rarely performed and the value of antibiotics is in doubt. Studies like this may sound the death knell for routine RBUS, at least for children with antenatal ultrasounds.