P3758 - Multi-Disciplinary Approach to Ischemic Colitis Due to Arteriovenous Malformations in the Inferior Mesenteric Artery

Byung K.. Lee, MD¹, Maunoo Lee, MD¹, Brian K. Cox, MD², Andrew Su, MD^3
1Naval Medical Center San Diego, San Diego, CA; ²Pacific Rim Pathology, San Diego, CA; ³Sharp Healthcare, San Diego, CA

Introduction: We present an unusual case of ischemic colitis secondary to inferior mesenteric artery arteriovenous malformations (AVMs).

Case Description/Methods: A 60-year-old female with history of hypertension, unspecified seizure disorder, and anxiety disorder presented initially for screening colonoscopy following a positive Fecal Immunochemical Test but also in the setting of 3 months of defecatory left lower quadrant abdominal pain and hematochezia. Colonoscopy showed non-specific hypervascularity and patchy mild erythema from the rectum to mid-transverse colon with targeted sigmoid colonic biopsies suggestive of possible ischemic injury. C-reactive protein elevated to 10.6 mg/L but infectious stool tests were unremarkable. Computed tomography angiography did not reveal any occlusive mesenteric disease. Despite 10 days of empiric Ciprofloxacin and Metronidazole, abdominal pain and hematochezia worsened with subsequent interval sigmoidoscopy revealing linear ulceration in the sigmoid with biopsy displaying active inflammation concerning for ischemic versus vasculitic injury versus early Crohn’s disease. Short course of budesonide and mesalamine were given but without any relief. Due to persistent symptoms, visceral angiogram with Interventional Radiology (IR) was performed which revealed extensive AVMs along the branches of the inferior mesenteric artery (IMA) [Image 1]. IR performed pre-operative embolization and coiling of the input from the IMA AVM followed by robotic sigmoid colectomy with end colostomy with Colorectal Surgery. Surgical pathology was consistent with acute on chronic ischemic changes. Patient recovered well from her surgery with no further recurrent symptoms and subsequent colonoscopy at 6 months was normal.

Discussion: The incidence of inferior mesenteric artery AVMs are extremely rare with fewer than 25 cases reported in literature so far and among those, only 12 cases were associated with ischemic colitis. In addition, treatment of the condition varied among cases to only embolization versus surgery versus combined embolization and surgery. This case in discussion highlights the step-wise progression of the disease, ability to masquerade as a chronic colitis, and also presents the unique intervention of pre-operative embolization and coiling of the IMA prior to surgical resection. This case emphasizes the importance of considering mesenteric arteriovenous malformations as part of the differential diagnosis for ischemic colitis.



Disclosures:


Byung K.. Lee, MD¹, Maunoo Lee, MD¹, Brian K. Cox, MD², Andrew Su, MD³. P3758 - Multi-Disciplinary Approach to Ischemic Colitis Due to Arteriovenous Malformations in the Inferior Mesenteric Artery, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.