Can diagnostic and imaging recommendations from the 2011 AAP UTI guidelines be applied to infants

Abstract

In 2011, the American Academy of Pediatrics (AAP) published guidelines regarding diagnosis and management of children 2-to-24-months-old with initial febrile urinary tract infection (fUTI). Available data were insufficient to determine whether evidence from studies of 2-to-24-month-olds applies to those <2-months-old, so they were excluded. This study aimed to 1) compare demographic, clinical, imaging and outcomes between patients <2-months-old and those 2-to-24-months-old hospitalizedwith fUTI, and 2) assess whether diagnostic and imaging recommendations of the AAP 2011 guidelines apply to those <2-months-old. A cohort study of patients ≤24-months-old hospitalized at a children's hospital with fUTI from 2016 to 2018 was conducted. Data were collected via a prospectively generated electronic medical record note template, supplemented with retrospective chart review. Primary outcomes included differences in demographics, clinical presentation, urine culture results, and imaging utilization/results by age group. Secondary outcomes included surgical procedures, UTI recurrence, and 90-day all-cause readmissions and emergency department (ED) revisits. Univariate and bivariate statistics were utilized to compare age groups. Overall, 137 patients were included (median age 70 days, 55.5% male [92.1% uncircumcised], 53.3% Hispanic/Latino, 89.8% 1st fUTI). There were no demographic differences between groups, except children <2-months-old were more frequently male (71.2 vs 43.6%, p=0.002). The Summary Table compares clinical factors and imaging utilization byage. There were no differences in urinalysis or urine culture results between groups. Patients <2-months-old had shorter fever duration, lower maximum temperature, and lower white blood cell counts. Voiding cystourethrograms (VCUGs) were recommended and obtained more frequently in patients <2-months-old, but there were no differences in renal and bladder ultrasound (RBUS) or VCUG results between age groups. There were no differences in UTI recurrence (13.6% of <2-months-old vs 14.1% of 2-to-24-months-old, p=1.00) or fUTI recurrence (13.6 vs 7.7%, p=0.40) within 1 year, 90-day readmission (6.8 vs 6.4%, p=1.00), or 90-day ED revisit (22.0 vs 20.5%, p=1.00). There were minimal differences between the <2-months-old and 2-to-24-months-old age groups in demographics, laboratory (including microbial) or imaging results, or clinical outcomes. Patients <2-months-old were more frequently male and less ill. These data support applying urinalysis and urine culture diagnostic criteria, and universal RBUS, from the AAP guidelines to patients <2-months-old. Given utilization differences, applicability of VCUG guideline recommendations requires further clarification for patients <2-months-old. Laboratory testing and RBUS recommendations from the AAP guidelines may be safely applied to infants <2-months-old. Further studies are needed to clarify optimal VCUG recommendations.