Comparison of fidaxomicin, metronidazole and vancomycin for initial episode and recurrence of Clostridioides difficile infection - An observational cohort study.

Objectives The main aim of this study was to compare the clinical outcomes of patients attended in our area with Clostridioides difficile infection (CDI) (sustained cure, recurrence or death) in relation to treatment to normal or hypervirulent C. difficile as a risk factor and to describe the resistance profile to metronidazole and vancomycin antibiotics in our hospital over a one-year period. Methods A retrospective, cross-sectional and observational study was conducted between June 2022 and June 2023 to compare the clinical cure and/or recurrence of CDI in adult patients treated in a Spanish secondary Hospital depending on the prescribed antibiotic treatment. In addition, we performed an antimicrobial susceptibility study to vancomycin and metronidazole in all C. difficile isolated in bacterial culture. Results Out of 194 selected patients the treatments were as follow: 43.81% vancomycin, 21.65% metronidazole, 8.25% a combination of both, 6.70% fidaxomicin and 19.59% were untreated. Vancomycin and fidaxomicin patients had higher odds ratio of prolonged hospitalization (p=0.041 and p=0.040, respectively). Fidaxomicin had increased odds of suffering another episode of C. difficile (p=0.009) and it was inferior to metronidazole for recurrent CDI (rCDI) (p=0.035).Resistance profile for C. difficile was 4.07% for vancomycin and 3.49% for metronidazole. Hypervirulent C. difficile was identified in 17 (8.76%) patients with 29.41% of mortality (5/17; p>0.05). Conclusion Fidaxomicin treated patients had statistically increased odds of rCDI. Compared to other treatments, fidaxomicin was inferior to metronidazole for rCDI in our cohort;Hypervirulent C. difficile was not associated with death.Vancomycin resistance of C. difficile statistically decreased, whereas metronidazole resistance did not vary during the studied period.