Clinical Characterization and Healthcare Burden of Difficult-to-Treat Inflammatory Bowel Disease in Latin America: a real-world registry-based study

Inflammatory Bowel Disease (IBD) is increasing across Latin America (LATAM). We aimed to determine the frequency and characteristics of difficult-to-treat IBD (DTT-IBD) in this region, using international consensus criteria. Retrospective study using data from IBD registries across eleven LATAM countries: the EPILATAM-IBD study (nine countries), the Brazilian national IBD registry, and two Argentinian single-center registries. Adults with ulcerative colitis (UC), Crohn’s disease (CD), or unclassified IBD were included. DTT-IBD was defined as meeting at least one of the following criteria: failure of ≥ 2 advanced mechanisms of action, chronic antibiotic-refractory pouchitis, CD recurrence after ≥2 resections, or complex perianal CD. Comparisons between DTT and non-DTT groups were performed using Mann-Whitney and Chi-square/Fisher exact tests (p < 0.05). Among 5,699 patients with complete data [40% CD, median disease duration 9 years (Q1-Q3: 5-15)], 747 (13%) met DTT-IBD criteria. DTT prevalence was higher among CD (30%) than among UC patients (2%). Complex perianal disease predominated in DTT-CD (91%), whereas failure of ≥ 2 advanced mechanisms of action predominated in DTT-UC (93%). Compared to non-DTT patients, those with DTT-IBD were younger at symptom onset [median age 24 (19-34) years] and IBD diagnosis [26 (21–37) years], and had longer time until diagnosis (p-value <0.001). DTT-CD was associated with penetrating behavior (39%) and ileocolonic disease (46%); DTT-UC with extensive colitis (83%). DTT-IBD affected 13% of patients treated in LATAM, with nearly one-third of individuals with CD presenting more severe phenotypic features. These findings highlight the need for comprehensive IBD care strategies in this complex patient population.