S2533 An Unusual Finding Lurking in the Colon

Introduction: Deep Invasive gastrointestinal endometriosis (DIGIE) is rare. Out of all endometriosis cases, 7-12% of cases can have gastrointestinal involvement, ranging from single lesions, to multiple lesions, to full colonic stenosis. Symptoms can include dyspareunia, dysmenorrhea, infertility, dysphasia, diarrhea, constipation, bloating, and rectal bleeding. Here we present a patient who was incidentally found to have endometrioma. Case Description/Methods: A 24-year-old female with a past medical history significant for polycystic ovarian syndrome, HIV and endometriosis, presented to the hospital with chief complaints of fever, dysuria, hematochezia, and lower abdominal pain which had been ongoing for 3-4 days. On admission, the patient was noted to be hemodynamically stable. Abnormal laboratory results included hematocrit 32.6% (reference range 36-46%), hemoglobin 10.2 g/dL (reference range 12-16 g/dL), mean corpuscular volume 72.4 fL (reference range 80-100 fL), ferritin 15.8 ng/mL (reference range 6.3-137 ng/mL), total iron binding capacity 306 mcg/dL (reference range 265-497 mcg/dL), and iron 19 mcg/dL (reference range 37-170 mcg/dL). The following day, she underwent a colonoscopy which showed isolated diverticulosis involving the sigmoid colon. There was an active oozing diverticulum that was successfully treated with endoscopic clip placement. At the rectosigmoid junction, there was a 3 cm submucosal lesion bulging into the lumen. This appeared to have a smooth surface and was without ulceration. Biopsies were taken and the pathology showed submucosal granulation tissue with chronic inflammatory reaction and iron deposition. CD10 specific immunostains were positive, suggesting the diagnosis of an endometrioma (Figure). Discussion: This case highlights an incidental finding of DIGIE. It is important to think about colonic involvement in patients with endometriosis who have GI complaints. Rarely, these lesions can cause obstruction and may require surgery. There are currently no formal guidelines or recommendations, with most of these patients being managed on a personalized basis. Management for these patients includes symptomatic therapies, progresterones, colonic shaving, disc excision, and laparoscopic resection. As for our patient, she pursued conservative symptomatic management with close outpatient Gynecology follow up.Figure 1.: A 3 cm submucosal lesion bulging into the lumen at the rectosigmoid junction.