Background. Few studies have examined the impact of rapid viral diagnostic tests on patient management.

Objective. To assess the effect of rapid diagnosis of influenza A infections on patient management.

Methods. The medical records of children with respiratory infections who were evaluated at a children's hospital between July 1, 1995, and June 30, 1997, were reviewed. Children (n= 56) evaluated in the Emergency Department (ED) who had a positive influenza A enzyme immunoassay (EIA) were compared with two control groups for the likelihood of admission, antibiotic use and duration of hospitalization and antibiotic administration.

Results. Patients discharged from the ED with a positive EIA test were less likely to receive antibiotics than those with a negative EIA test (20%vs.53%;P= 0.04). Patients admitted to the hospital with a positive EIA test were as likely to receive antibiotics as those without a rapid diagnosis, but the duration of antibiotic administration was significantly shorter in the group with a positive EIA test (3.5vs.5.4 days;P= 0.03). Patients with a positive EIA test also were more likely to receive antiviral therapy than either control group (25%vs.0 and 1.8%;P< 0.001).

Conclusions. The detection of influenza A by EIA has a positive impact on medical management by decreasing antibiotic use in pediatric patients evaluated in an ED, by decreasing the duration of antibiotic use in hospitalized patients and by encouraging antiviral therapy.