12 Asymptomatic Double Small Bowel Intussusception in a Patient With Ulcerative Colitis Flare: A Rare and Incidental Finding

Introduction: Ulcerative colitis (UC) is a chronic inflammatory disease of the colon and rectum with a relapsing–remitting course marked by bloody diarrhea, abdominal cramping, and urgency. Prevalence is highest in Europe (505 per 100,000), followed by Canada (248 per 100,000) and the USA (214 per 100,000). Intussusception—the telescoping of one bowel segment into another—is exceptionally uncommon in adults and rarely reported in UC (9 cases in the literature). Adult cases overall are estimated at 500–800 annually. In inflammatory bowel disease, intussusception is observed more often in Crohn’s disease than UC, typically when a structural lead point or postoperative change exists. In UC, proposed mechanisms include mucosal edema–related dysmotility and giant pseudopolyps acting as lead points. Case: A 52-year-old man with alcohol use disorder and iron deficiency anemia presented with one month of bloody diarrhea, tenesmus, and 20-lb weight loss. Colonoscopy showed diffuse ulceration and friability consistent with severe ulcerative pancolitis (Mayo 3), and biopsy demonstrated active chronic colitis. He improved on intravenous steroids and was discharged on an oral taper. Prior records documented colitis in 2017 with skip lesions and rectal involvement; a 2018 colonoscopy was quiescent with mild architectural distortion, leaving the IBD subtype uncertain. A sibling history of Crohn’s disease was present. Five days post-discharge, he re-presented with odynophagia and retrosternal chest pain. CTA of the chest, abdomen, and pelvis—performed to assess pulmonary embolism and bleeding—revealed mild distal esophageal wall thickening and incidental, short-segment small-bowel intussusceptions in the right and left lower quadrants without obstruction or adjacent inflammation. He remained asymptomatic with a benign abdominal exam and improving hematochezia on prednisone. Surgery was deferred; he received therapy for esophagitis and was discharged with outpatient follow-up. Discussion: This case highlights a phenotype of transient, multifocal enteroenteric intussusception emerging during active colitis yet discovered incidentally and without obstructive physiology. Imaging literature recognizes that short-segment intussusceptions lacking upstream dilatation, bowel-wall compromise, or inflammatory stranding are often self-limited and can be safely observed in adults. Our patient’s duality of intussusceptions argues for a systemic, inflammation-driven motility disturbance rather than a single fixed lead point. UC flare–related edema and inflammatory mediators may disrupt neuromuscular coupling and peristaltic timing, predisposing to telescoping events that recede as inflammation is treated. This interpretation reconciles the rarity of UC-associated intussusception with its occurrence in reported cases where inflammatory polyposis or giant pseudopolyps provide a mechanical nidus, and it also explains why UC trails Crohn’s disease, in which transmural inflammation and mass-forming lesions more readily create durable lead points. Clinically, management should begin with confirming the transient imaging pattern and correlating it with bedside exam; in this context, observation with steroid therapy is appropriate, with escalation only if symptoms persist, obstruction evolves, or imaging suggests a mass. Should the clinical picture change, MR/CT enterography and targeted endoscopy are warranted to interrogate subtle lead points and mimics that may masquerade as IBD-related intussusception. Conclusions: Asymptomatic, short-segment double small-bowel intussusception can arise during a UC flare as an imaging marker of inflammation-altered motility. When unobstructed and clinically silent, observation is reasonable.