Adult Ileocolic Intussusception Secondary to Appendiceal Mucocele: A Report of a Rare Case.

Adult intussusception is a rare and diagnostically challenging condition, often caused by an underlying pathological lead point such as neoplasms, with presentations that are typically nonspecific and intermittent, including abdominal pain, nausea, vomiting, and altered bowel habits. Among unusual causes, appendiceal mucoceles represent a rare but clinically significant entity that can precipitate intussusception, carrying a risk of serious complications like pseudomyxoma peritonei (PMP) if ruptured. We report the case of a 58-year-old male presenting with right lower quadrant pain, nausea, and intermittent bowel habit changes, in whom imaging revealed ileocolic intussusception with a cystic lesion suggestive of an appendiceal mucocele. The patient underwent laparoscopic-assisted right hemicolectomy, with en bloc resection of the intussuscepted segment and mucocele, avoiding rupture. Histopathology confirmed a low-grade appendiceal mucinous neoplasm without invasion or lymphovascular involvement. The patient recovered uneventfully, and follow-up demonstrated no recurrence or complications. This report highlights the importance of high-resolution imaging in identifying both intussusception and its lead point, the necessity of maintaining suspicion for neoplastic causes in adults, and the critical role of careful surgical management to prevent morbidity and ensure favorable outcomes.