Advanced phenotypes and favorable 1-year outcomes with accelerated step-up strategy in newly diagnosed inflammatory bowel disease in a tuberculosis-endemic, resource-constrained setting

Background: The incidence of inflammatory bowel disease (IBD) is rising across Southeast Asia, yet real-world data on clinical phenotypes, treatment strategies, and outcomes in tuberculosis (TB)-endemic, resource-constrained settings remain scarce. Objectives: To characterize disease phenotypes, treatment utilization, and 1-year outcomes in a Vietnamese inception cohort of newly diagnosed IBD patients in a tuberculosis-endemic, resource-constrained setting. Design: Single-center, hybrid retrospective–prospective inception cohort study. Methods: Consecutive adults diagnosed with Crohn’s disease (CD) or ulcerative colitis (UC) at a tertiary referral center in Ho Chi Minh City, Vietnam, between June 2019 and June 2024. A Baseline Cohort ( N = 126) was analyzed for phenotypic characterization. Patients completing ⩾12 months of follow-up comprised the Outcome Cohort ( N = 66) for assessment of treatment patterns and clinical, biochemical, and endoscopic outcomes. Treatment followed an accelerated step-up strategy with originator anti-tumor necrosis factor (TNF) agents (infliximab/adalimumab) after mandatory TB screening. Results: Among 126 patients (80 CD, 46 UC), CD was characterized by substantial diagnostic delay (median 12 months), with 57.6% presenting stricturing or penetrating behavior and 25.0% having undergone intestinal resection before IBD confirmation. Extensive colitis (E3) predominated among UC patients (63.0%), and 78.3% had moderate-to-severe disease. Anti-TNF utilization increased from 13.6% within the first 2 months after diagnosis to 45.5% at 1 year. In the Outcome Cohort ( N = 66), steroid-free clinical remission was achieved in 63.6%, and mucosal healing was documented in 62.3% of endoscopically evaluated patients. Serious infections occurred in 9.1%, with TB reactivation in 4.5%. Conclusion: IBD in Vietnam presents with diagnostic delays, complicated phenotypes, and high surgical rates at initial presentation. Despite these challenges, an accelerated step-up strategy with early anti-TNF escalation was associated with favorable 1-year steroid-free remission and mucosal healing rates. These findings suggest that treat-to-target care with early biologic escalation may be feasible in selected patients in TB-endemic, resource-constrained settings, provided that structured TB monitoring is implemented.