Mesenteric ischaemia in haemodialysis patients: a case/control study.

BACKGROUND: Mesenteric ischaemia is not uncommon in dialysis patients and seems to have been increasing in the last decade. However, the risk factors for mesenteric ischaemia are unclear and prognosis of patients after this type of ischaemic accident is not well defined. METHODS: From January 1988 to June 1999, 15 haemodialysis patients (0.3% per patient-year) from a single institution presented with mesenteric ischaemia and the clinical, biological and radiological aspects of the ischaemia were described. To identify risk factors for mesenteric ischaemia, each ischaemic patient (case) was matched with two other haemodialysis patients not having ischaemia (controls). Survival curves were then established for the two groups. RESULTS: A marked hypotensive episode was present in seven out of 15 case patients (47%) during dialysis sessions that preceded mesenteric ischaemia. Abdominal pain, guarding, fever and hyperleucocytosis were all present in 13 out of 15 patients (87%). An abdominal computerized tomography scan with opaque enema enabled a rapid diagnosis for six patients. The caecum was the most frequently (47%) affected segment. Twelve patients were surgically treated and the remaining three were given medical support. The two groups (case and control) were not different in cardiovascular risk factors, comorbidity, administered drugs or main haemodialysis characteristics. The median survival of the case group was 600 days, whereas 80% of the control group survived beyond this period (P=0.0132). Eleven case patients survived >3 months after mesenteric ischaemia and had a median survival of 1500 days, which was identical to their matched control patients. CONCLUSIONS: Mesenteric ischaemia should be systematically suspected in patients experiencing abdominal pain during or after dialysis sessions. Prompt diagnosis and treatment usually allow for a favourable prognosis.