Abstract Background Campylobacter species (spp) infection has been linked to the development of inflammatory bowel disease (IBD), but its impact on the clinical course of patients with established IBD remains unclear. We aimed to assess the incidence and clinical consequences of Campylobacter spp. infection in patients with IBD. Methods We conducted a retrospective, propensity score-matched cohort study at a tertiary referral center in Spain. We identified all positive stool tests between 2010 and 2024. Patients aged ≥14 years old with Campylobacter infection were matched in a 1:2 ratio with uninfected controls using propensity score matching adjusted for age, sex, disease extent, and year of diagnosis. Results Among 2,662 positive Campylobacter spp. stool cultures, 42 (1.57%) occurred in patients with IBD (20 Crohn’s disease CD, 22 ulcerative colitis UC). The incidence of Campylobacter infection was higher in patients with IBD compared to non-IBD population (1.656% vs. 0.576%; RR 2.87; 95% CI: 2.13–3.87; p 0.0001). Infected patients had an increased risk of flare (71.3% vs. 28.7%; p = 0.007), hospital admission (78.6% vs. 21.4%; p 0.001), and treatment intensification (75% vs. 25%; p = 0.013) within the first year after infection. In the multivariate analysis, Campylobacter infection was independently associated with worse disease outcomes, with significantly accelerated time to treatment escalation (HR 4.41, 95% CI 1.05–18.46; p = 0.043) and hospitalization (HR 11.20, 95% CI 1.81–69.37; p = 0.009). Conclusion Campylobacter spp. infection risk is increased in patients with IBD and it is associated with worse prognosis, increasing the risk of flare, hospitalization, and therapeutic intensification need during the first 12 months. These findings highlight the need for close follow-up and tailored management strategies after infection Conflict of interest: Ms. Alanon, Paloma: No conflict of interest Orti Cuerva, Marina: No conflict of interest Muñoz-Peña, Marta: No conflict of interest Causse, Manuel: No conflict of interest Benítez Cantero, José Manuel: JMB has served as a speaker, consultant and advisory member or has received grants or honoraria for scientific activities and presentations from Dr. Falk Pharma, Faes Farma, Ferring, Shire Pharmaceuticals, Chiesi, Tillotts Pharma, MSD, Abbvie, Takeda, Janssen. Marin Pedrosa, Sandra: NO Soto Escribano, Pilar: No conflict of interest Iglesias Flores, Eva: has served as a speaker, consultant and advisory member for or has received research funding from AbbVie, Janssen, Takeda, Gillead, Celgene, Pfizer, Lilly, Ferring, Faes Farma, Dr. Falk Pharma, Chiesi, and Adacyte, Gros, Beatriz: Beatriz Gros has served as a speaker for Abbvie, Johnson and Johnson, Takeda, Roche, Gilead, Pfizer and Galapagos and has served as an advisor for Roche, Gilead, Abbvie, Galapagos and Takeda
Alañón et al. (Thu,) studied this question.