Testing for Meningitis in Febrile Well-Appearing Young Infants With a Positive Urinalysis

To determine factors associated with cerebrospinal fluid (CSF) testing in febrile young infants with a positive urinalysis and assess the probability of delayed diagnosis of bacterial meningitis in infants treated for urinary tract infection (UTI) without CSF testing.

We performed a retrospective cohort study using data from the Reducing Excessive Variability in Infant Sepsis Evaluation quality improvement project. A total of 20 570 well-appearing febrile infants 7 to 60 days old presenting to 124 hospitals from 2015 to 2017 were included. A mixed-effects logistic regression was conducted to determine factors associated with CSF testing. Delayed meningitis was defined as a new diagnosis of bacterial meningitis within 7 days of discharge.

Overall, 3572 infants had a positive urinalysis; 2511 (70.3%) underwent CSF testing. There was wide variation by site, with CSF testing rates ranging from 64% to 100% for infants 7 to 30 days old and 10% to 100% for infants 31 to 60 days old. Factors associated with CSF testing included: age 7 to 30 days (adjusted odds ratio [aOR]: 4.6; 95% confidence interval [CI]: 3.8-5.5), abnormal inflammatory markers (aOR: 2.2; 95% CI: 1.8-2.5), and site volume >300 febrile infants per year (aOR: 1.8; 95% CI: 1.2-2.6). Among 505 infants treated for UTI without CSF testing, there were 0 (95% CI: 0%-0.6%) cases of delayed meningitis.

There was wide variation in CSF testing in febrile infants with a positive urinalysis. Among infants treated for UTI without CSF testing (mostly 31 to 60-day-old infants), there were no cases of delayed meningitis within 7 days of discharge, suggesting that routine CSF testing of infants 31 to 60 days old with a positive urinalysis may not be necessary.