S3932 A Bizarre Bridge: Colosalpingeal Fistula as a Complication of Sigmoid Diverticulitis

Introduction: Fistula formation is a known complication of acute diverticulitis and can form throughout multiple adjacent organs or structures with an initial incidence of 2%-4%, rising to 20% in those with prior history of surgical treatment for diverticular disease. Colosalpingeal fistulas, forming between the intestine and fallopian tubes, are very rare with few recorded cases. Here we present a case of a postmenopausal woman who presented with diverticular disease progressing to formation of a left colosapingeal fistula. Case Description/Methods: A 60-year-old postmenopausal woman with prior medical history of Hodgkin’s lymphoma with remission and ectopic pregnancy status-post dilatation and curettage who presented to our institution with sudden-onset abdominal pain. The patient arrived tachycardic and physical exam was remarkable for diffuse tenderness to palpation. WBC on arrival was 21,400/μL. Computed tomography (CT) of the abdomen and pelvis showed marked sigmoid wall thickening consistent with diverticulitis. Intravenous antibiotics (zosyn) were started. Persistent fevers and no significant improvement in the initial leukocytosis were noted in the first days of hospitalization. A repeat CT was performed and showed an anterior contained sigmoid perforation. The patient remained clinically stable and did not require surgical intervention at the time. Another repeat CT scan was performed as a method of monitoring the perforation and development of a left colosalpingeal fistula was seen. MRI of the pelvis was then performed to confirm findings. The patient’s recurrent fevers resolved by the fifth day of admission, and it was determined that patient would require long term antibiotics. A peripheral central line was placed. The patient was discharged on a 6-week course of Invanz and then underwent colonoscopy which showed no significant findings. Sigmoidectomy with concurrent bilateral salpingoophorectomy (BSO) was performed later as part of definitive management. Discussion: Colosalpingeal fistulas are difficult to diagnose as symptoms can be nonspecific. CT scans are the gold standard for diagnosis, and management will depend on the patient’s desire to maintain fertility. Definitive management in postmenopausal women is sigmoid resection with BSO. This case highlights the importance of multispecialty management in rare complications of diverticulitis.