Case Report of Urachal Remnant Causing Extensive Fistulization between the Sigmoid Colon and Bilateral Adnexae with Cyst-Cutaneous Fistula

Abstract We present the case of a 20-year-old female with purulent umbilical drainage. Workup initially included a contrast-enhanced computed tomography scan of the abdomen and pelvis, which revealed large bilateral tubo-ovarian abscesses communicating with a tract to the umbilicus, with concern regarding involvement of the sigmoid colon. A drain was placed, and cultures from the abscess demonstrated growth of α-hemolytic streptococci and Trueperella (Arcanobacterium) bernardiae. Colonoscopy was normal. During preparation for colonoscopy, the patient noted passage of high volume of clear fluid from the umbilicus. A fistulogram through the umbilical opening revealed a complex fistulous network involving the umbilicus, bilateral adnexa and rectosigmoid, with concern for small bowel involvement. Magnetic resonance enterography was unremarkable for bowel inflammation, but the study suggested the possibility of an underlying urachal remnant. Diagnostic laparoscopy was performed, which excluded presence of any small bowel involvement, and demonstrated dense adhesions of the omentum and left adnexa to the abdominal wall. Ultimately, the patient underwent a multi-disciplinary robotic-assisted urachal remnant excision, with en-bloc left oophorectomy and sigmoidectomy. Urachal and omphalomesenteric remnants outside of the pediatric population are rare. To the best of our knowledge, this is the first report of such complication of a urachal remnant, with a complex fistula involving the rectosigmoid colon, adnexa and bladder. Here, we present the diagnostic and operative approach.