Background.Enterovirus (EV) infections can be rapidly detected by PCR. However, several studies suggest that results must be available early in the management of the patient to impact significantly on patient care. We evaluated this hypothesis directly during an outbreak of EV aseptic meningitis.Methods.From June through November, 1998, EV PCR was performed 5 days a week on cerebrospinal fluid specimens from pediatric patients evaluated for meningitis. We compared antibiotic use, length of stay and hospital charges in a group of patients with EV meningitis whose positive EV PCR results were available within 24 h of specimen collection, to a group of similar patients whose results were available >24 h after collection.Results.Cerebrospinal fluid specimens were submitted for EV PCR from 113 patients with suspected EV meningitis, and 50 of 113 (44%) were positive. Of these 50 EV-PCR-positive patients, 17 of 50 (34%) had EV PCR results available in ≤24 h and 33 of 50 (66%) had results available in >24 h. Patients with EV-positive results reported ≤24 h after specimen collection had 20 h less of antibiotic use (P= 0.006) and $2798 less in hospital charges (P= 0.001) than patients with positive results available in >24 h. Hospitalized patients who received positive results rapidly did not have significantly less antibiotic therapy or shorter length of stay, but hospital charges were reduced by $2331 (P= 0.009).Conclusion.Rapid reporting of PCR results can have a significant impact on several outcome measures for patients with EV meningitis.