2379. It’s Getting Complicated: Outcomes of Clostridiodes difficile PCR Positive/Toxin-Negative Patients

Background The addition of toxin enzyme immunoassay to molecular tests creates challenges in the diagnosis and management of Clostridiodes difficile infection (CDI). In limited samples of PCR+/ toxin- patients, CDI-attributable complications are thought to be rare, even nonexistent. We aimed to characterize outcomes of a large PCR+/ toxin− cohort within 60 days of initial testing date. Methods We conducted a retrospective cohort study on all PCR+/toxin- adult inpatients from June–December 2018. Patients were placed into 3 groups to analyze outcomes: (1) complete treatment (guideline concordant); (2) incomplete treatment; and (3) no treatment. The primary outcome in group (1) was CDI-related complication, defined as megacolon, colectomy, or ICU care. For groups (2) and (3), clinical failure was defined as a composite of: need for repeat CDI testing or subsequent treatment. Results We identified 240 individuals (Figure 1). Mean age was 60 years, and 122 (51%) were female. 173 (72%) received complete treatment (85% vancomycin monotherapy), 41 (17%) incomplete treatment, and 26 (11%) none. Baseline conditions included high severity comorbidities (Figure 2). In the complete treatment group, 10/173 (5.8%) patients met criteria for fulminant colitis. 21/173 (12%) experienced CDI-attributable complications (2 megacolon, 1 colectomy, 18 ICU care). A significantly higher proportion of these patients had leukocytosis >15,000 (57 vs. 23%; P = 0.001), creatinine >1.5 (57 vs. 27%; P = 0.005), and were receiving concomitant proton pump inhibitors (65 vs. 43%; P = 0.05) and antibiotics (65 vs 44%; P = 0.05) compared with those without CDI-related complications. In patients who received incomplete treatment, there were 10 clinical failures (7 had repeat testing; 3 were administered complete treatment) compared with 4 in the no treatment group (Figure 3). Interestingly, 4/9 (44%) patients who had incomplete or no treatment and underwent repeat testing were found to be PCR+/ toxin+. There were 4 (1.7%) deaths related to CDI in the cohort. All occurred in the complete treatment group. Conclusion CDI-attributable complications and clinical failure occur in PCR+/toxin− patients. The challenge of distinguishing colonization from disease remains. Additional studies are needed to identify predictors of disease in PCR+/ toxin− patients. Disclosures All authors: No reported disclosures.