Sigmoid colon endometriosis as an uncommon cause of large bowel obstruction: A case report

Introduction and importance

Large bowel obstruction (LBO) is most commonly caused by neoplasms, but rare etiologies like endometriosis should be considered, as bowel involvement can mimic other gastrointestinal disorders and lead to obstruction. Sigmoid endometriosis is a rare but important cause of LBO, which can lead to symptoms ranging from subtle gastrointestinal complaints to overt obstruction. Laparoscopy is the primary diagnostic tool, and surgery is often part of the treatment when obstruction occurs.

Case presentation

We report the case of a 51-year-old Arab female with a history of ulcerative colitis and chronic abdominal symptoms, who presented with progressive distension and intermittent constipation. Colonoscopy revealed a non-passable sigmoid stricture. Surgical resection was performed, and histopathology showed benign endometrial tissue in the colonic wall, confirming sigmoid endometriosis.

Clinical discussion

Endometriosis is a chronic inflammatory condition that can involve various intraperitoneal and extraperitoneal sites, with intestinal involvement reported in up to 37 % of cases—most commonly in the rectum and sigmoid colon. Gastrointestinal symptoms are often nonspecific and may mimic irritable bowel syndrome, making diagnosis challenging. Imaging modalities often lack specificity, while laparoscopy remains the gold standard. In this case, the diagnosis was only confirmed after surgical resection and histopathological analysis. Although medical therapy can be effective in symptom control, surgical excision becomes necessary when obstructive symptoms are present, as seen in our patient.

Conclusion

This case underscores sigmoid colon endometriosis as an uncommon yet significant cause of large bowel obstruction. Awareness of such rare presentations is essential for timely diagnosis and management.