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

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 orderingEBP >3 days was established with the option to override the restriction. The presentstudy 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 fromNovember 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 patientswithout 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. difficilereceived treatment and their C. difficilepositive test resulted >1 day before the EBP was run. There were no differencesin yield in patients >65 years of age with significantcomorbidities or associated with neutropenia, leukocytosis, human immunodeficiencyvirus 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 havenot been tested for more common causes of hospital-acquired diarrhea.