What is the risk of bacterial meningitis in infants who present to the emergency department with fever and pyuria?

OBJECTIVE: To determine the rate of bacterial meningitis among febrile infants in the emergency department (ED) who have pyuria detected in an initial catheterized urine specimen.

METHODS: This retrospective chart review, conducted at the Hospital for Sick Children, Toronto, Ont., involved all children aged 0 to 3 months who presented to the ED with fever and pyuria (>/=10 white blood cells/mm(3)) over a 3-year period. Cerebrospinal fluid (CSF) was evaluated using standard methods, and the rate of meningitis in children with pyuria was determined.

RESULTS: The study sample included 211 infants with fever and pyuria -- 79 of these under 1 month of age. Eighty-one percent (171/211) had positive urine cultures, and 143 underwent lumbar puncture to rule out meningitis. Of these, 140 CSF samples were culture negative and 3 grew coagulase negative Staphylococcus -- 2 because of contamination and 1 because of a ventriculo-peritoneal shunt infection. Both children with CSF contamination grew Escherichia coli in the urine. The rate of bacterial meningitis in the study sample was 0% (95% confidence interval, 0%-2.6%).

CONCLUSIONS: In this study of febrile children under 90 days of age with fever and pyuria, the incidence of concurrent meningitis was 0%. This suggests that recommendations for mandatory lumbar puncture in such children should be reconsidered. However, until larger prospective studies define a patient subset that does not require CSF analysis, it is prudent to rule out meningitis, administer parenteral antibiotics for urinary tract infection, and admit for close observation.