Ischemic colitis due to obstruction of mesenteric and splenic veins: a case report

Abstract

Ischemic injury to the bowel is a well known disease entity that has a wide spectrum of pathological and clinical findings. A sudden drop in the colonic blood supply is essential to its development. We encountered a 41-year-old male patient, who presented with abdominal pain and bloody diarrhea. A colonoscopy showed markedly edematous mucosa with tortuous dilatation of the veins and a deep ulceration at the rectosigmoid junction. On an abdominal computed tomography (CT) scan and CT angiography, the mesenteric and splenic veins were absent with numerous venous collaterals for drainage. The patient gradually responded to oral aminosalicylate therapy, and was in remission after nine months. In most cases, non-occlusive ischemic injury is caused by idiopathic form and occlusive ischemia is caused by abnormalities of arteries and acute venous thrombosis. However, chronic venous insufficiency due to obstruction of macrovascular mesenteric vein rarely causes ischemia of the bowel. This report describes the first case of ischemic colitis caused by obstruction of the mesenteric and splenic veins.

Figure 1

Colonoscopic findings. A, B: Tortuous and dilated submucosal veins in the colonic mucosa; C: Diffuse and edematous mucosa with fine granularity resembling ulcerative colitis; D: A deep ulceration at rectosigmoid junction.

Figure 2

Dynamic abdominal CT. A: The normal anatomy of the main portal vein and its tributaries including the portal vein (PV), left gastric vein (LGV), gastrocolic trunk (GCT), splenic vein (SV), SMA, SMV, and IMV are schematically illustrated; B: The normal mesenteric vein (SMV and IMV) and splenic vein are absent. Numerous collateral venous channels developed to drain venous blood from gastrointestinal tract to portal vein.

Figure 3

Abdominal CT arteriography. A: Normal shape and course of SMA, IMA, and splenic artery, tortuous and dilated distal branches of SMA and IMA around rectosigmoid colon; B: An axial and C: Coronal reformatted abdominal CT reveal the absent splenic vein, SMV, and IMV with numerous intra- and peripancreatic collaterals. Distal end portal vein is abruptly ended (black arrow) and SMA is normal (white arrow). Note prominent dilated pericolic arteries and venous collaterals, and markedly thickened sigmoid colon.