A new study describes the outcome of a new approach to testing for Clostridioides difficile, guided by the principles of diagnostic stewardship and how it highlights the benefits of a clearly defined, evidence-based test-ordering process.
Published in the American Journal of Infection Control (AJIC), the study describes how revised rules for when C. difficile tests could be ordered at Memorial Healthcare System in Hollywood, Florida, helped to reduce inappropriate testing by 20%, which in turn can help rein in the overtreatment of patients.
C. difficile is a common and potentially dangerous gastrointestinal pathogen, often linked to healthcare-associated infections and the overuse of antibiotics. While early diagnosis can be helpful in ensuring that patients receive the right treatment, inappropriate testing may identify patients who are harmlessly colonised with the bacteria rather than suffering from an acute infection. Guidelines from infectious disease organizations recommend targeted testing for patients demonstrating clear symptoms associated with C. difficile, rather than broader testing for all patients with gastrointestinal symptoms, to avoid unnecessary treatment.
In this study, clinicians from Memorial Healthcare System developed and implemented new guidelines to help reduce inappropriate testing for C. difficile and monitored results across the patient population for nine months to evaluate the approach. Those results were compared to testing performed in the year preceding the new ordering guidelines. The study reports results from 224 adult patients, 118 tested based on the new method and 106 from before the guidelines were implemented.
The new ordering approach involved two sets of rules: one for patients admitted within the last 72 hours, for whom C. difficile testing could be ordered without restriction for any patient who recently had at least three loose or unformed stools, and the other for patients who had been in the hospital for four days or more. For the latter group, C. difficile testing could not be ordered for patients who had been given laxatives within 48 hours, who had been treated for C. difficile 14 to 24 days prior, or who had tested positive for C. difficile within 14 days. Patients who had been tested for C. difficile in the past four days, even if they received a negative result, were also not eligible for a new test. For high-risk patients, such as those who were immunocompromised or had recently undergone gastrointestinal surgery, C. difficile tests could be given even if other eligibility guidelines were not met. The new system was integrated with the hospital’s electronic health records to ensure consistency and documentation, and educational resources were distributed to staff members.
Clinicians found a 20.1% reduction in C. difficile test orders deemed inappropriate under the new system compared to the year prior to implementation, from 31.1% of tests before the new guidelines to just 11% with them. Testing was defined as inappropriate when patients did not have enough incidence of diarrhoea reported or when there was recent laxative use without other signs of infection.
“The goal of diagnostic stewardship is to use the right test for the right patient at the right time, and that means we must use tests appropriately and judiciously to ensure they provide results that can help guide patient care,” said Rachel Guran MPH BSN RN CIC FAPIC, Director of Epidemiology and Infection Prevention at Memorial Healthcare System and an author of the study. “We are very pleased that our new guidelines for C. difficile testing led to a clear decrease in inappropriate test ordering, which has benefits for reducing unnecessary treatment and associated healthcare costs.”
- Eckardt P, Guran R, Jalal AT, et al. Impact of an electronic smart order-set for diagnostic stewardship of Clostridiodes difficile infection (CDI) in a community healthcare system in South Florida. Am J Infect Control. 2024 May 7:S0196-6553(24)00341-9. doi:10.1016/j.ajic.2024.04.181. Online ahead of print.