Clinical and demographic factors associated with urinary tract infection in young febrile infants.

OBJECTIVE: Previous research has identified clinical predictors for urinary tract infection (UTI) to guide urine screening in febrile children <24 months of age. These studies have been limited to single centers, and few have focused on young infants who may be most at risk for complications if a UTI is missed. The objective of this study was to identify clinical and demographic factors associated with UTI in febrile infants who are < or =60 days of age using a prospective multicenter cohort.

METHODS: We conducted a multicenter, prospective, cross-sectional study during consecutive bronchiolitis seasons. All febrile (> or =38 degrees C) infants who were < or =60 days of age and seen at any of 8 pediatric emergency departments from October through March 1999-2001 were eligible. Clinical appearance was evaluated using the Yale Observation Scale. UTI was defined as growth of a known bacterial pathogen from a catheterized specimen at a level of (1) > or =50000 cfu/mL or (2) > or =10000 cfu/mL in association with a positive dipstick test or urinalysis. We used bivariate tests and multiple logistic regression to identify demographic and clinical factors that were associated with the likelihood of UTI.

RESULTS: A total of 1025 (67%) of 1513 eligible patients were enrolled; 9.0% of enrolled infants received a diagnosis of UTI. Uncircumcised male infants had a higher rate of UTI (21.3%) compared with female (5.0%) and circumcised male (2.3%) infants. Infants with maximum recorded temperature of > or =39 degrees C had a higher rate of UTI (16.3%) than other infants (7.2%). After multivariable adjustment, UTI was associated with being uncircumcised (odds ratio: 10.4; bias-corrected 95% confidence interval: 4.7-31.4) and maximum temperature (odds ratio: 2.4 per degrees C; 95% confidence interval: 1.5-3.6). Factors that were reported previously to be associated with risk for UTI in infants and toddlers, such as white race and ill appearance, were not significantly associated with risk for UTI in this cohort of young infants.

CONCLUSIONS: Being uncircumcised and height of fever were associated with UTI in febrile infants who were < or =60 days of age. Uncircumcised male infants were at particularly high risk and may warrant a different approach to screening and management.