Accuracy and impact of a point-of-care rapid influenza test in young children with respiratory illnesses

Objective: To determine whether a point-of-care rapid influenza test impacts the diagnostic evaluation and treatment of children with acute respiratory illnesses. Design: Randomized controlled trial. Setting: Pediatric emergency department and acute care clinic of a children's hospital. Participants: Children aged younger than 5 years with fever or acute respiratory symptoms during 2 influenza seasons ( 2002 through 2004). Interventions: Surveillance days were randomized to performance or no performance of a point-of-care rapid influenza test. All children had a nasal and throat swab obtained for laboratory tests. The rapid test group had another nasal swab obtained for the QuickVue Influenza Test (Quidel Corp, San Diego, Calif), which was performed by nurses; results were shared immediately with treating physicians. Main Outcome Measures: Rapid test results were compared with results of the viral culture or 2 polymerase chain reaction assays for influenza. Diagnostic test ordering and antibiotic prescribing were compared for the groups. Results: Of 468 enrolled children, 306 were from the emergency department and 162 from the clinic. Overall, 88 children (19%) had influenza infection. Of 205 children in the rapid test group, 51 (25%) had influenza infection. The rapid influenza test was 82% sensitive and 99% specific. In the emergency department, fewer children in the rapid test group had diagnostic tests ordered than in the no rapid test group (39% vs 51%, P=.03). There was no difference in test ordering in the clinic or in antibiotic prescribing in either setting. The use of antivirals was low. Conclusions: Point-of-care rapid influenza tests were sensitive and specific and were associated with less diagnostic testing in the emergency department.