3070 A Rare Case of 5-Fluorouracil-Induced Ulcerative Colitis

Abstract

INTRODUCTION: 5-Fluorouracil (5-FU), an antimetabolite used in the management of advanced gastrointestinal cancers, is often complicated by the development of colitis with several reported cases. However, there has been no report of new onset ulcerative colitis (UC) following 5-FU-based chemotherapy. We report a case of 5-FU-induced UC in a patient with no previous personal or family history of inflammatory bowel disease (IBD). CASE DESCRIPTION/METHODS: A 60-year-old Caucasian female presented to the emergency department with 1-month history of diarrhea, abdominal pain, nausea and vomiting. Her past medical history is notable for hypertension, gastroesophageal reflux disease and recently diagnosed stage III invasive cecal adenocarcinoma for which she had right-sided hemicolectomy 3 months prior. She also received 3 cycles of adjuvant chemotherapy (folinic acid, fluorouracil and oxaliplatin) with the last cycle being five weeks ago. She had no previous history of colitis or IBD and had been asymptomatic prior to receiving chemotherapy. She was afebrile, mildly tachycardic with moderate tenderness in bilateral lower abdominal quadrants. Apart from anemia, her labs including stool studies and dihydropyrimidine dehydrogenase test were normal. She had little response to conservative management with fluids, antidiarrheals and antibiotics. Colonoscopy showed diffuse severe mucosa inflammation and ulceration with histology suggestive of an emerging IBD and negative for CMV. Fecal calprotectin was significantly elevated. Following minimal improvement with mesalamine and confirmation of UC by serology, she was started on steroids, azathioprine and infliximab with subsequent abatement of symptoms. DISCUSSION: Colitis is a significant gastrointestinal complication of chemotherapy. The four most common chemotherapy-induced colitis subtypes in the literature are neutropenic enterocolitis, pseudomembranous colitis, ischemic colitis and anti-CTLA4 antibody enterocolitis. 5-FU is a potent cause of colitis and majority of cases resolve with cessation of chemotherapy and supportive treatment. UC may be considered as a complication of 5-FU especially in the presence of corroborative laboratory, imaging and endoscopic features as well as poor response to conventional management. In addition to withdrawal of chemotherapy, treatment should be initiated per standard management of UC. Benefits and risks of biologic therapy should be thoroughly assessed. This case illustrates the rare potential for UC following 5-FU-based chemotherapy.