Testing for Urinary Tract Infection in the Influenza/Respiratory Syncytial Virus–Positive Febrile Infant Aged 2 to 12 Months

Abstract

Objective Infants 12 months or younger with influenza and respiratory syncytial virus (RSV) commonly present to the emergency department (ED) with fever. Previous publications have recommended that these patients have a urinalysis and urine culture performed. We aimed to assess the prevalence of urinary tract infection (UTI) in febrile RSV/influenza positive infants aged 2 to 12 months presenting to the ED. We also examined whether the 2011 American Academy of Pediatrics (AAP) UTI clinical practice guidelines could be used to identify patients at lower risk of UTI. Methods This was a retrospective chart review examining all infants aged 2 to 12 months with a documented fever of higher than 38°C who presented to our ED from 2009 to 2013 and tested positive for influenza and/or RSV. Results One thousand seven hundred twenty-four patients were found to meet our inclusion criteria. Of these, 98 were excluded because of known urinary tract anomaly or systemic antibiotic use in the 24 hours preceding evaluation. Of those patients remaining, 10 (0.62%) of 1626 had positive urine cultures (95% confidence interval, 0.3%–1.1%), and 8 (0.49%) of 1626 (95% confidence interval, 0.2%–0.97%) had positive urine cultures with positive urinalyses as defined in the 2011 AAP UTI clinical practice guidelines. All subjects with positive urine cultures as defined by the AAP had risk factors for UTI that placed their risk for UTI above 1%. Conclusions Our population of 2- to 12-month-old febrile infants with positive influenza/RSV testing, who did not have risk factors to make their risk of UTI higher than 1%, may not have required evaluation with urinalysis or urine culture.

Association of Diagnostic Criteria With Urinary Tract Infection Prevalence in Bronchiolitis

“…1,24,29,30 All of the studies excepting 2 required fever as part of the inclusion criteria. 1,26,29,30,33 Three of the studies ex-clusively included infants younger than 90 days. 24,29,30 Overall quality scores ranged from 5 to 7 on a 7-point scale.…”

“…45 The recommended diagnostic criteria were subsequently revised in 2011 to include both an abnormal UA result and a positive urine culture for infants older than 2 months. 11 All 3 of the bronchiolitis studies 1,26,33 published after the 2011 guidelines included subanalyses comparing diagnosis based on urine culture alone with urine culture plus a positive UA result; however, the definitions that they used to define a positive urine culture and UA were disparate. 1,26,33 The revised AAP recommendations exclude infants younger than 2 months, the highest risk population for serious bacterial infections and where questions regarding the reliability of the UA still linger.…”

“…However, when a positive UA result was included as a diagnostic criterion, the prevalence of UTI was 0.8% (95% CI, 0.33-1.40; I 2 = 39%) ( Figure 3). From the 7 studies providing UA data, a sensitivity analysis removing 3 studies that defined bronchiolitis only by respiratory syncytial virus testing 26,32,33 did not substantially alter the summary statistics, producing a point estimate for UTI of 1.0% (95% CI, 0.1%-2.7%; I 2 = 61%) when a positive UA result was required. Similarly, for the studies exclusively including infants younger than 90 days, 24,29,30 the point estimate for concomitant UTI with positive UA was 0.5% (95% CI, 0.1%-1.2%; I 2 = 0%).…”

“…In total, the weighted propor- tion of E coli UTIs was 63.9% in bronchiolitis. 1,24,26,30,32,33 When applying the diagnostic criterion of a positive UA result, the weighted prevalence of E coli was 80.3%. 1,24,26,30,33…”

<p>Why Are Children With Bronchiolitis At Risk Of Urinary Tract Infections?</p>

“…Recently, McDaniel et al 17 conducted a systematic review and meta-analysis exploring the prevalence of UTI in infants and young children with bronchiolitis when positive urinalysis (UA) results being incorporated into the UTI definition. The investigators included 18 studies, [4][5][6][7]9,[11][12][13]15,16,[18][19][20][21][22][23][24][25] seven of which had UA information. 4,11,16,18,[20][21][22] The definition of positive UA varied among the studies.…”