Cerebrospinal Fluid Enterovirus Testing in Infants 56 Days or Younger

OBJECTIVE: To determine whether cerebrospinal fluid (CSF) enterovirus polymerase chain reaction (PCR) testing of febrile neonates is associated with a shorter hospital length of stay (LOS). DESIGN: Retrospective cohort study. SETTING: Urban tertiary care children's hospital emergency department. PARTICIPANTS: Febrile infants 56 days or younger evaluated by means of lumbar puncture. MAIN EXPOSURE: Performance of CSF enterovirus PCR testing. MAIN OUTCOME MEASURE: Hospital LOS. RESULTS: A CSF enterovirus PCR test was performed in 361 of 1231 eligible infants (29.3%); 89 of those tested (24.7%) were positive. The median LOS was 2 days. In multivariable analysis, CSF enterovirus PCR testing was associated with a 26.0% shorter LOS for infants with a positive test result (adjusted beta coefficient, -0.305; 95% confidence interval, -0.457 to -0.153; P < .001) and an 8.0% longer LOS for those with a negative test result (0.075; -0.021 to 0.171; P = .12) compared with untested infants. In stratified analysis, LOS was shorter for all infants 28 days or younger who tested positive regardless of receipt of antibiotics before lumbar puncture. For infants 29 to 56 days old, a positive test result was associated with a shorter LOS only in those not previously receiving antibiotics. The median (interquartile range) turnaround time for CSF enterovirus PCR testing was 22.2 (15.1-27.4) hours, with no effect of turnaround time on LOS. CONCLUSIONS: Among infants 56 days or younger, a positive CSF enterovirus PCR test result was associated with a shorter LOS compared with untested infants. The CSF enterovirus PCR test may improve the care of infants with fever.