Abstract
BACKGROUND: Fulminant Clostridioides difficile infection (FCDI) is associated with a 30%-40% mortality rate. Guideline definitions for FCDI severity classification include ileus, megacolon, shock, or hypotension. However, no hypotension definition is provided, making application of the definition challenging. The objective of this study was to assess optimal hypotension definitions for FCDI severity criteria. METHODS: This was a multicenter cohort study involving 1172 hospitalized patients diagnosed with C difficile infection (CDI) from 2015 to 2022 (Houston cohort). Patients were assessed for a composite endpoint of colectomy or mortality within 30 days of diagnosis. The ability of the CDI severity criteria to predict the composite endpoint was assessed using 2 definitions of hypotension (systolic blood pressure [SBP] ≤90 mm Hg and mean arterial pressure [MAP] ≤65 mm Hg) through multivariable regression models. A separate CDI cohort of 494 hospitalized patients validated the results (Midwest cohort). RESULTS: The composite endpoint was similar in the Houston cohort (98 patients [8.4%]) and the Midwest cohort (26 patients [5.3%]). Using either a MAP ≤65 mm Hg or SPB ≤90 mm Hg as criteria for hypotension was the best-performing model in both the development and validation cohorts. Removal of hypotension was the worst-performing model in both cohorts. CONCLUSIONS: Inclusion of hypotension, defined as SBP ≤90 mm Hg or MAP ≤65 mm Hg, was an important component of FCDI severity criteria, significantly improving the predictive ability to identify FCDI patients at risk for poor outcomes.