Two haemodialysis patients with unclear abdominal symptoms of similar origin.

Ischaemic colitis (IC) is a dangerous condition usually caused by atherosclerosis and low blood flow states w1x. Haemodialysis (HD) patients are at increased risk of IC because they have accelerated rates of arterial vascular disease w2x and because hypotension is common during dialysis with large amounts of fluid removal. Thus, IC in the HD patient is usually attributed to atherosclerotic origin. However, there are many other conditions that can contribute to IC including arterial occlusion, thrombosis, factors that increase blood viscosity, constipation causing increased intraluminal pressure w3,4x, digoxin which acts as a splanchnic vasoconstrictor, impaired baroreflex sensitivity in chronic renal failure, and, rarely, neoplasm w5,6x or amyloidosis w7–10x. We report two cases of IC in HD patients of nonatherosclerotic aetiology. The first case is a unique presentation of IC in a HD patient in association with previously undiagnosed non-Hodgkins lymphoma encroaching on mesenteric vessels. The second case is a HD patient with amyloidosis who presented with and subsequently died from IC and was found to have extensive amyloid involvement of the colon evident on post-mortem examination. Cases