Urachal Cyst Causing Small Bowel Obstruction in an Adult with a Virgin Abdomen.

Introduction. A patent urachus is a rare congenital or acquired pathology, which can lead to complications later in life. We describe a case of urachal cystitis as the etiology of small bowel obstruction in an adult without prior intra-abdominal surgery. Case Report. A 64-year-old male presented to the acute care surgery team with a 5-day history of right lower quadrant abdominal pain, distention, nausea, and vomiting. He had a two-month history of urinary retention and his past medical history was significant for benign prostate hyperplasia. On exam, he had evidence of small bowel obstruction. Computed tomography revealed high-grade small bowel obstruction secondary to presumed ruptured appendicitis. In the operating room, an infected urachal cyst was identified with adhesions to the proximal ileum. After lysis of adhesions and resection of the cyst, the patient was subsequently discharged without further issues. Conclusion. Although rare, urachal pathology should be considered in the differential diagnosis when evaluating a patient with small bowel obstruction without prior intraabdominal surgery, hernia, or malignancy.