Atherosclerotic complications are the leading cause of death in chronic renal failure (CRF) patients. Therefore, we wished to investigate the prevalence of carotid artery lesions (CALs) in these subjects. Two groups were evaluated by high-resolution echo Doppler: group 1 included 103 patients (68 males and 35 females) affected by nonnephrotic CRF and group 2 included 100 control subjects (60 males and 40 females). The prevalence of hypertension was 84% in both groups. The exclusion criteria included diabetes mellitus and symptoms of cerebrovascular disease. In the two groups we evaluated clinical history, physical examination, total cholesterol, triglycerides, fibrinogen, blood cell counts, blood urea nitrogen, creatinine, 24-hour proteinuria, and urine analysis. In group 1 patients the following lipid profile parameters were also evaluated: low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, lipoprotein(a), ApoAI, ApoAII, and ApoB. Group 1 had higher triglycerides and fibrinogen than group 2. A lower body mass index was found in group 1 than in group 2. The prevalence of CALs was significantly higher in the CRF patients than in the control subjects (62% v 47%; P = 0.04). The difference between the two groups was more striking among normotensive patients (62% v 19%; P = 0.03). All CRF patients affected by peripheral arterial disease and 86% of those having coronary artery disease had associated CALs. In CRF patients the severity of CALs was positively correlated to age, white blood cell count, triglycerides, and fibrinogen. Nondiabetic CRF patients have a higher prevalence of carotid artery lesions than control subjects. Several factors besides hypertension, including lipids, blood coagulation, and leukocytes, could contribute to the accelerated atherosclerosis of CRF patients.