Gastroenterology
IBD meets C diff: AGA updates guidance for a high-risk intersection
Clinical Takeaway: In IBD patients with suspected CDI, test early and treat with fidaxomicin (preferred) or vancomycin—while continuing necessary immunosuppression—and proactively prevent recurrence with microbiome-based therapies after the first relapse.
AGA’s 2026 Clinical Practice Update highlights the growing complexity and urgency of managing Clostridioides difficile infection (CDI) in patients with inflammatory bowel disease (IBD), who face markedly higher risks of severe disease, recurrence, hospitalization, and surgery. Because symptoms overlap, the authors stress that any new or worsening diarrhea in IBD warrants CDI testing, preferably using a multistep toxin-based assay to distinguish active infection from colonization.
A major shift is drug strategy. Fidaxomicin is now the preferred first-line therapy for initial CDI in IBD due to similar cure rates but lower recurrence and less microbiome disruption compared with vancomycin; vancomycin remains acceptable when access or cost is limiting. Metronidazole is no longer recommended. For recurrent disease, clinicians should escalate quickly, considering fidaxomicin regimens, vancomycin tapers, and especially microbiome restoration approaches.
Importantly, the update counters a common clinical reflex: do not stop IBD therapy during CDI. The panel emphasizes continuing immunomodulators, biologics, or small molecules, and even using corticosteroids when needed for active IBD. “Concurrent treatment of IBD is critical,” the authors note, underscoring that uncontrolled inflammation can worsen outcomes as much as infection.
Microbiome-based therapies represent one of the most notable advances. AGA now recommends offering FDA-approved microbiota products or fecal microbiota transplantation after just one recurrence to prevent further episodes—reflecting strong efficacy signals and the high recurrence burden in IBD. In contrast, probiotics are discouraged for prevention due to lack of benefit and potential risks in immunocompromised patients.
Additional practical guidance includes considering hospitalization for severe presentations, reassessing with endoscopy if symptoms persist after 48 to 72 hours, and selectively using loperamide only after clinical improvement begins. For high-risk patients with prior CDI who need systemic antibiotics, oral vancomycin prophylaxis may be considered, though evidence remains limited.
Overall, the update reinforces early diagnosis, targeted antibiotic selection, and aggressive recurrence prevention—while maintaining control of the underlying IBD.
Source: Khanna S, et al. (2026, May 15). Gastroenterology. AGA Clinical Practice Update on Management of Clostridioides difficile Infection in Inflammatory Bowel Disease: Expert Review