Abstract
Treatment guidelines for Clostridioides difficile infection (CDI) have been published by infectious disease and gastroenterology professional societies; however, adherence in clinical practice remains poorly characterized, particularly for recurrent disease. We conducted a retrospective chart review of 100 patients with CDI (350 episodes: 115 initial, 235 recurrent) referred to a tertiary complicated CDI clinic between 2018 and 2023. Guideline adherence was assessed by comparing treatment with IDSA/SHEA and ACG recommendations, and referring diagnoses were compared with final specialist diagnoses. Guideline adherence was significantly higher in initial compared to recurrent episodes (70.4% vs. 41.3%, p < 0.0001). Among guideline non-adherent recurrent episodes, 51.3% used standard antibiotic regimens inappropriate for the recurrence tier. Specialist review reclassified 12.0% of episodes, with colonization increasing from 2.6% to 8.9%. Misdiagnosed colonization cases had a 6.2-fold higher treatment failure rate than confirmed CDI (39.3% vs. 6.3%, p < 0.0001). Guideline non-adherence showed a non-significant trend toward treatment failure (10.0% vs. 6.7%, p = 0.31). Guideline adherence for recurrent CDI is inadequate in pre-referral settings, and diagnostic misclassification is common. Early specialist involvement may improve both diagnostic accuracy and treatment appropriateness for patients with recurrent CDI.