Uncovering Ulcerative Colitis with Bilateral Sacroilitis in a Patient of Chronic Back Pain: A Case Report

Ulcerative Colitis (UC) is the most common type of Inflammatory Bowel Disease (IBD), characterised by persistent and progressive inflammation. Unlike Crohn’s Disease (CD), which affects the entire thickness of the intestinal wall, UC is limited to the mucosal and submucosal layers of the colon and rectum. The condition typically begins in the rectum and may gradually extend proximally to involve other segments of the colon. Sacroiliitis refers to inflammation of the sacroiliac joints at the base of the spine and often presents with lower back and buttock pain. It is more common in individuals with ulcerative colitis due to shared immune-mediated inflammatory pathways. Hereby, the authors present a case of a 35-year-old male who arrived at hospital with complaints of back pain radiating to the left lower limb for the past 5-6 days, along with 5-6 episodes of loose stools over the preceding 10 days. Magnetic Resonance Imaging (MRI) of the lumbar spine revealed diffuse bowel wall thickening as an incidental finding. Subsequently, a contrast-enhanced MRI of the abdomen was performed, which demonstrated features suggestive of ulcerative colitis with bilateral sacroiliitis. Radiologists play a crucial role in identifying early or subtle manifestations of disease, particularly in asymptomatic or occult cases, thereby facilitating timely clinical suspicion.