924. Reducing Rates of Hospital Acquired Clostridium Difficile Infection by Switching to Two-Step Testing


 
 
 Clostridium difficile infection (CDI) tests have various degrees of sensitivity, making diagnosis challenging. Polymerase chain reaction (PCR) positive tests in colonized patients can impact rates of hospital-acquired CDI (HACDI). A negative toxin A/B enzyme immunoassay (EIA) as a second step can help determine colonization but is not as sensitive. We aimed to study the impact of a two-step testing strategy on rates of HACDI and CDI treatment outcomes.
 
 
 
 Two-step testing consisted of C. difficle DNA PCR, which if positive, was followed by toxin A/B EIA (Figure 1). We conducted a retrospective study in a 359-bed hospital from March 2020 to July 2021. Patients with positive PCR and negative EIA results were included and further classified based on CDI treatment status. The primary outcome was the number of HACDI cases avoided. Secondary outcomes included location at the time of testing, symptoms, leukocytosis, discharge disposition and readmission.
 
 
 
 Ninety-six patients were included. Sixty-five patients (68%) were treated while 31 (32%) were not. HACDI was avoided in 18 cases (18.8%). There were more HACDI avoided in the non-treated group compared to the treated group (32.3% vs 12.3%; p=0.026). Most non-treated patients were tested on medical-surgical units (77.4%), whereas 49.2 % of the treated patients were tested in more acute areas such as emergency or intensive care. Treated patients were more likely to have leukocytosis and/or fever (66.2%) compared to non-treated patients (29%; p= 0.0009), while there was no difference in abdominal pain, diarrhea, bloody stool, or constipation (Table 1).
 Most patients had an abdominal CT scan (70.8%). Of those that had a CT, colitis was found in 48.5%. Patients in the treated group were more likely to have had a CT completed that showed colitis vs the non-treated patients (43.1% vs 16.1%; p< 0.011).
 Finally, compared to the non-treated patients, treatment did not affect home disposition on discharge or 30-day readmission rate (80% vs 71%, P=0.436) and (25 % vs 29%, P= 0.63) respectively.
 Symptoms Associated with C. difficile infection.
 Schematic of C. difficile test interpretation.
 
 
 
 CDI two-step testing led to decreased HACDI rates without affecting discharge disposition or readmission rates in patients with PCR positive and toxin EIA negative results regardless of treatment status.
 
 
 
 All Authors: No reported disclosures.
