Colonic Endometriosis: A Case of Chronic Abdominal Pain

Purpose: A 43-year-old white female presented to clinic for further evaluation of two years of abdominal pain mostly on the left side, dull, sometimes sharp, worsening after eating, improving after bowel movements and no associated bloody stools. Patient had a history of deep venous thrombosis and pulmonary embolism three years prior treated with coumadin for one year. A few months prior to presentation patient had acute right upper quadrant pain leading to computer tomography (CT) of the abdomen demonstrating portal vein thrombosis and superior mesenteric vein (SMV) thrombosis causing treatment initiation with coumadin again. Patient underwent evaluation for thrombophilia disorders and malignancy resulting in a colonoscopy, which revealed a nonbleeding mucosal ulceration in the proximal ascending colon and initial biopsy consistent with chronic inflammation. Repeat colonoscopy one month later demonstrated a persistent ulcer in the mid-ascending colon with biopsies revealing endometriosis. Patient's gynecologic history involved two previous gestations, a caesarean section, uterine fibroids and hysterectomy many years prior. No history of endometriosis. Further evaluation at our hospital involved CT enterography demonstrating a nonocclusive thrombus in the SMV and occlusive thrombus in the right ileocolic branch. Colonoscopy showed granularity and nodularity in the ascending colon without ulceration, and biopsy revealed colonic mucosa with associated inflammation with stroma and focal glands suggestive of endometriosis. Patient underwent evaluation by vascular surgery concluding no surgery was necessary since adequate vessels were present to supply gut through collaterals. Hematology evaluation revealed a negative complete coagulation survey. Gynecology desired to pursue a trial with lupron (leuprolide) injections. Colorectal surgery recommended to continue anticoagulation longer and to monitor on hormonal suppression and if improvement plan for laparoscopic right colon resection. Colonic endometriosis is a rare entity that can present with a variety of manifestations making it difficult to diagnose. It most commonly affects pre-menopausal women in early forties around half of which demonstrate previous pelvic endometriosis. Most commonly it presents with abdominal pain and can be associated with stenosis, polyps, mural masses, and ulcers. However, intestinal endometriosis is rarely found within the superficial mucosa of the intestine, with estimates around 30% confirmed on endoscopy. Surgical resection is the gold standard for those with refractory symptoms, and is often when a tissue diagnosis becomes available. Endoscopic ultrasound with tissue sampling may provide diagnosis if routine endoscopy fails.