Background and Importance Clostridioides difficile infection (CDI) is the main cause of infectious diarrhoea in the hospital setting.

Aim and Objectives The aim of this study is to analyse the use and effectiveness of fidaxomicin in CDI.

Material and Methods An observational, descriptive and retrospective study was conducted in patients treated with fidaxomicin between April 2018-August 2023. Variables, collected through the electronic medical record, were: sex, age, patient location, immunosuppression, severity and type of episode, previous antibiotic treatment, indication, dose and duration, time to clinical cure (days between fidaxomicin started and diarrhoea resolution) and recurrence (presence of diarrhoea or positive toxin in stool within 4 weeks after treatment). Effectiveness was assessed by clinical cure rate, recurrence rate and overall cure rate (absence of stool-positive toxin and diarrhoea within 4 weeks after treatment). Outpatients were excluded from the clinical cure analysis. Continuous variables are expressed as median and interquartile range while categorical variables as frequency and percentage.

Results A total of 37 patients were included, 17 (46%) male, aged 73 [62–80] years, 25 (67.6%) were inpatients and 14 (37.8%) immunocompromised. Most of them were severe cases with high risk of recurrence (20 (54.1%)).

Most patients received fidaxomicin during the first (13 (35.1%)) or higher (16 (40,5%)) recurrence episode and only 8 (21.6%) during the first CDI episode. Previously, 28 (75,7%) patients had received oral vancomycin and 22 (59.5%) metronidazole. Vancomycin refractoriness (35 (94.6%)) was the main indication. The dose used in all cases was 200mg/12h for 10 days [10–15].

The effectiveness analysis was conducted in 35 patients (2 died during the study period) (table 1).

Conclusion and Relevance In this study, fidaxomicin has been shown to be effective in resolving CDI diarrhoea , although with a less favourable clinical cure, recurrence and overall cure rate than obtained in pivotal trials. Due to the small sample size further research is needed to support the results obtained here.

Conflict of Interest No conflict of interest.