An electronic medical record-based decision support matrix implemented as a stewardship intervention reduced the frequency of Clostridioides difficile testing and the number of patients potentially overtreated with antibiotics, and improved the fidelity of the tests, researchers reported.
“An estimated 4% [to] 15% of hospitalized patients are colonized with C. difficile, which increases to [approximately] 50% for patients admitted from long-term care,” Michele S. Fleming, MSN, RN, CIC an infection preventionist for the Virginia Commonwealth University Health System’s Healthcare Infection Prevention Program, and colleagues wrote. “Overdiagnosis of [C. difficile infection] increases with more sensitive testing strategies, such as nucleic acid amplification testing.”
Fleming and colleagues conducted a retrospective study at an academic medical center. They reviewed EMRs for testing fidelity, which was confirmed if patients had clinically significant diarrhea, no laxative use within 24 hours, and confirmation of additional symptoms or risk factors, such as a temperature higher than 100.4°F, abdominal pain or tenderness within 48 hours, a white blood cell count of more than 15,000/mm3 or less than 4,000/mm3 within 48 hours, antibiotic use or a discharge from any health care facility within 30 days of testing. They included any C. difficile PCR tests completed between January and June of 2017 and January and June of 2018 in the study.
The EMR decision support matrix, developed to assist clinicians with the appropriate ordering C. difficile tests, was implemented on March 28, 2018.
Between January and June 2017, 1,797 tests were performed, of which 247 were positive for C. difficile, according to Fleming and colleagues. Comparatively, 1,327 tests were performed between January and June of 2018, of which 224 were positive for C. difficile.
Fleming and colleagues reported that 61% of the positive cases in 2017 did not meet testing criteria, compared with 35% of positive cases in 2018. Additionally, 82% of the patients in 2017 and 91% of patients in 2018 who did not meet testing criteria were treated with CDI-targeted antibiotics.
The researchers then looked at the rate of tests performed between April and June of 2017, and April and June of 2018 — after the EMR decision support matrix was implemented. They found that of the 874 tests performed in 2017, 35% met testing criteria compared with 51% of the 639 tests performed in 2018.
“Thus, there was a 27% reduction in total C. difficile testing and a statistically significant improvement in test fidelity after the intervention,” Fleming and colleagues wrote.
Moreover, when the researchers compared the second quarters of 2017 and 2018, they observed a statistically significant reduction in the National Healthcare Safety Network C. difficile hospital-onset event incidence rate after the EMR intervention began (P < .03).
“Our experience highlights the impact of testing volume as a driver of C. difficile rate,” Fleming and colleagues said. “Additional studies are needed to optimize C. difficile testing strategies and to minimize the potential harms of C. difficile underdiagnosis.” – by Marley Ghizzone
Disclosures: The authors report no relevant financial disclosures.