Effect of Rapid Respiratory Virus Testing on Antibiotic Prescribing Among Children Presenting to the Emergency Department With Acute Respiratory Illness: A Randomized Clinical Trial.

Importance: There is high usage of antibiotics in the emergency department (ED) for children with acute respiratory illnesses. Studies have reported decreased antibiotic use among inpatients with rapid respiratory pathogen (RRP) testing. Objective: To determine whether RRP testing leads to decreased antibiotic use and health care use among children with influenzalike illness (ILI) in an ED. Design, Setting, and Participants: A randomized clinical trial among children aged 1 month to 18 years presenting to an ED with ILI from December 1, 2018, to November 30, 2019, was conducted. Data were analyzed March 23, 2020, to April 2, 2021. All children received a nasopharyngeal swab for RRP testing and were randomized 1:1 to the intervention group or control group (results not given, routine clinical care). Results were available in 45 minutes. Intention-to-treat analyses and modified intention-to-treat (clinician knows results) analyses were conducted using multivariable Poisson regression. Interventions: Rapid respiratory pathogen test results given to clinicians. Main Outcomes and Measures: Antibiotic prescribing was the primary outcome; influenza antiviral prescribing, ED length of stay, hospital admission, and recurrent health care visits were the secondary outcomes. Results: Among 931 ED visits (intervention group, 452 children group and control group, 456 children after exclusion of those not meeting criteria or protocol violations), a total of 795 RRP test results (85%) were positive. The median age of the children was 2.1 years (interquartile range, 0.9-5.6 years); 509 (56%) were boys. Most children (478 [53%]) were Hispanic, 688 children (76%) received government insurance, and 314 (35%) had a high-risk medical condition. In the intention-to-treat intervention group, children were more likely to receive antibiotics (relative risk [RR], 1.3; 95% CI, 1.0-1.7), with no significant differences in antiviral prescribing, medical visits, and hospitalization. In inverse propensity-weighted modified intention-to-treat analyses, children with test results known were more likely to receive antivirals (RR, 2.6; 95% CI, 1.6-4.5) and be hospitalized (RR, 1.8; 95% CI, 1.4-2.5); there was no significant difference in antibiotic prescribing (RR, 1.1; 95% CI, 0.9-1.4). Conclusions and Relevance: The use of RRP testing in the ED for ILI did not decrease antibiotic prescribing in this randomized clinical trial. There is a limited role for RRP pathogen testing in children in this setting. Trial Registration: ClinicalTrials.gov Identifier: NCT03756753.