Impact of the COVID-19 Pandemic on Viral Respiratory Testing in Children With Abnormal Urinalysis.

OBJECTIVE: Respiratory viral panels (RVP) are common, expensive tests that often do not change treatment, especially in children with suspected urinary tract infections. In children with abnormal urinalysis (UA) results, we hypothesize that RVP overuse existed before the COVID-19 pandemic and has risen further after. METHODS: We conducted a single-center retrospective cohort study of children aged 0 to 24 months who presented to a quaternary care children's emergency department (ED) from March 2018 to May 2025 with abnormal UA results. Children with complex chronic conditions, required intensive care or respiratory support, or sepsis were excluded. The primary outcome was the proportion of children with RVP testing within periods of prepandemic (March 2018-February 2020), pandemic (March 2020-May 2023), and postpandemic (July 2023-May 2025). Secondary outcomes included ED revisits, antiviral use, and cost of testing. We assessed trends in RVP use across the periods using interrupted time series analysis. Cost was measured using Medicaid reimbursement fees. RESULTS: Our cohort included 7496 patients. The proportion of all children who received an RVP was 25.0% (95% CI, 23.1-27.0), 68.1% (95% CI, 66.5-69.7), and 66.1% (95% CI, 64.1-68.0) during prepandemic, pandemic, and postpandemic periods, respectively. There was an increase in viral testing during the pandemic compared with prepandemic period (P < .001) but without change between pandemic and postpandemic (P = .14). Viral testing was associated with no differences in ED revisits (P = .41). Only 134 patients (1.8%) received antivirals. The total cost of respiratory viral testing was $1 037 978. CONCLUSIONS: RVP testing increased during the COVID-19 pandemic in children with abnormal UA results and remained elevated postpandemic. RVP testing was costly and associated with low antiviral use. These results highlight opportunities for diagnostic stewardship.