An Atypical Cause of an Already Rare Condition - Isolated Rectal Ischemic Proctitis

Clinical experience and traditional teaching suggest that ischemia of the rectum is an extremely rare phenomenon due to a dual blood supply. Several cases have been reported in the literature but are generally associated with severe aortic trauma or systemic hypotension with poor prognosis and primarily supportive medical treatment often requiring proctectomy or colectomy. We report an atypical cause of rectal ischemia in an otherwise healthy patient with severe symptoms at presentation but a relatively benign course to date. A 48 year old female presented with acute, constant rectal pain and pressure, tenesmus and either small volume bowel movements with scant bright red blood or urgency with inability to pass stool. CT imaging revealed abnormal rectal circumferential mucosal thickening. Flexible sigmoidoscopy showed severe proctitis extending from the anal verge to 12 cm with an abrupt transition to normal mucosa. She was treated empirically for suspected ulcerative proctitis with 5-ASA enemas and then corticosteroid enemas with no improvement. The initial biopsies showed moderate ischemic-type changes including crypt withering and mucin depletion with no signs of viral cytopathy, dysplasia, thrombosis, vasculitis, amyloidosis or granulomata. Repeat endoscopic assessment revealed worsening inflammation with an ongoing ischemic appearance. Repeat biopsies were reviewed with a specialist gastrointestinal pathologist who confirmed severe ischemia. CT- and MR-angiograms showed grossly abnormal vasculature of the rectum with distal inferior mesenteric artery hypertrophy, superior rectal artery and vein hypertrophy, and features suggestive of a high-flow arterial malformation in the right sigmorectal region (see image). Vascular surgery and interventional radiology consultation was sought; it was felt that the malformation was causing a steal phenomenon leading to the local ischemia. She was offered further investigation and attempt at therapeutic ablation via catheter angiogram but the patient felt that the risk of rectal injury and need for abdominal perineal resection was too great to proceed. Thus, she was treated supportively with sucralfate enemas and reported steady symptomatic improvement. Repeat sigmoidoscopy prior to discharge showed persistent rectal inflammation with ulceration but slight improvement compared to previous. She was discharged home and reported continued improvement to near baseline and is currently awaiting endoscopic reassessment.1602_A Figure 1. MR-angiogram showing patients inferior mesenteric artery arteriovenous malformation1602_B Figure 2. Endoscopic image of patients ischemic proctitis

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.