A diagnostic stewardship approach to prevent unnecessary testing of an enteric bacterial molecular panel

Abstract

ABSTRACT After stool culture was replaced by an enteric bacterial panel (EBP) at the Johns Hopkins Hospital (JHH), many EBPs were ordered >3 days after admission (EBP >3 days) with low yield. To reduce unnecessary testing, a hard stop for ordering EBP >3 days was established with the option to override the restriction. The present study retrospectively evaluates the usefulness of overriding that restriction. A retrospective chart review was performed on all patients with an EBP >3 days at the JHH from November 2021 to October 2022. The override provided only one new diagnosis of Salmonella infection in a patient who developed diarrhea within 3 days of admission but was not tested by EBP until day 5. There were no positive EBPs >3 days in patients without diarrhea or who developed diarrhea >3 days after admission (diarrhea >3 days). Most patients with requests to override the restriction were also tested for Clostridioides difficile . All patients positive for C. difficile received treatment and their C. difficile positive test resulted > 1 day before the EBP was run. There were no differences in yield in patients > 65 years of age with significant comorbidities or associated with neutropenia, leukocytosis, human immunodeficiency virus status, or lactoferrin positivity. There were no positive tests in patients receiving stool softeners within the previous 48 hours of testing. Overriding the hard stop should not be approved in patients without diarrhea or with diarrhea >3 days, who received stool softeners within the previous 48 hours or have not been tested for more common causes of hospital-acquired diarrhea. IMPORTANCE Testing for enteric bacterial pathogens in patients hospitalized for more than 3 days is almost always inappropriate. Our study validates the utility of the 3-day rule and the use of clinical decision support tools to decrease unnecessary testing of enteropathogenic bacteria other than C. difficile . Overriding the restriction was very low yield. Our study highlights the importance of diagnostic stewardship and further refines the criteria for allowing providers to override the restriction while monitoring the impact of the interventions.