Introduction: Although fidaxomicin is an effective, first-line treatment for Clostridioides difficile infection (CDI), clinical trials demonstrating its efficacy have excluded patients with inflammatory bowel disease (IBD) and its effectiveness in this patient population is unclear. We aimed to assess the effectiveness of fidaxomicin in patients with IBD for the treatment of CDI.
Methods: This was a retrospective study of adult patients with IBD who were treated with fidaxomicin for CDI from 1/2017 through 12/2021 at three academic tertiary medical centers. Patient information obtained from the electronic medical record included demographics, IBD subtype and treatments, and history of CDI and treatments. CDI was defined as >3 loose bowel movements per day or change from baseline in active IBD and positive toxin enzyme immunoassay or PCR for toxigenic C. difficile. Patients were treated with fidaxomicin 200 mg twice daily for 10 days, or twice daily for 5 days followed by an extended regimen. The primary outcomes were treatment response, defined as resolution of diarrhea and/or negative CDI stool test, and time to CDI recurrence after fidaxomicin. Fisher’s exact test was used to evaluate the association between clinical factors and the primary outcomes.
Results: Thirty-eight patients met inclusion criteria. Patient characteristics and outcomes are listed in Table 1. Twenty-nine (76.3%) patients had one or more prior episodes of CDI before fidaxomicin treatment, and in 23 (60.5%) fidaxomicin was used after non-response to another first-line treatment. Resolution of CDI with fidaxomicin occurred in 60.5% (23/38) of patients, and 30.4% (7/23) developed CDI recurrence after treatment response. Nearly half (44.7%) of patients underwent fecal microbiota transplant (FMT) following treatment with fidaxomicin. Patients with extensive or pan- ulcerative colitis phenotype had less CDI recurrence compared to left-sided colitis or proctosigmoiditis (89.9% vs. 33.7%, p=0.015). Patients with FMT for CDI before fidaxomicin had no CDI recurrence after fidaxomicin versus 8 (30.8%) patients with CDI recurrence without prior FMT (p=0.039).
Discussion: In this patient cohort with IBD and CDI, approximately 60% responded to treatment with fidaxomicin, although CDI recurred in 35% of those patients. Almost one half of patients underwent FMT after receiving fidaxomicin. Larger controlled studies are needed to assess outcomes of fidaxomicin for CDI in IBD.
