Intestinal Ultrasound Guided Management in Inflammatory Bowel Disease

This is a single-center randomized controlled trial conducted at the IBD Clinic, Faculty of Medicine Siriraj Hospital, Mahidol University.

Adult patients with inflammatory bowel disease (Crohn's disease or ulcerative colitis) who are undergoing endoscopy for assessment of disease severity are randomized 1:1, using computer-generated block-of-four randomization, to either standard of care plus intestinal ultrasound (IUS) or standard of care alone. Participants are followed for 48 weeks.

Follow-up visits are scheduled every 2 months for participants with active disease (Mayo endoscopic score of 2 or higher, or SES-CD of 3 or higher) and every 4 months for participants in remission.

In the IUS arm, intestinal ultrasound is performed at every visit by physicians certified by the International Bowel Ultrasound Group (IBUS). The physician performing the ultrasound is blinded to the blood and stool test results obtained on the same day. Measured parameters include bowel wall thickness (BWT), color Doppler signal, and mesenteric fat hypertrophy.

Standard of care in both arms includes clinical disease activity scores (partial Mayo/PRO-2 for ulcerative colitis, or Harvey-Bradshaw Index/PRO-2 for Crohn's disease), complete blood count, C-reactive protein, fecal calprotectin, and colonoscopy as clinically indicated.

The primary outcome is the proportion of participants with a change in treatment during the 48-week follow-up period.

Inclusion criteria

• Diagnosis of inflammatory bowel disease for more than 2 months
• Age 18 years or older
• Undergoing endoscopy at enrollment for assessment of disease severity

Exclusion criteria

• Pregnancy
• Unstable underlying medical conditions
• Inflammatory bowel disease limited to the distal rectum (within 10 cm of the anal verge) or perianal disease only
• Biologic failure