OBJECTIVE:To evaluate whether a dietary protein restriction is useful for slowing the progression of chronic renal failure (CRF) in diabetic and nondiabetic patients and to analyze the possible risk of malnutrition after such a dietary regimen.DESIGN:Prospective, randomized case-control clinical trial.SETTING:Nephrology outpatients.PATIENTS AND OTHER PARTICIPANTS:A total of 169 patients, 89 affected with CRF and chronic hypertension and 80 affected with overt diabetic nephropathy (24 suffering from type 1 and 56 from type 2 diabetes) and chronic hypertension.INTERVENTION:Diabetic patients and nondiabetic patients were randomly divided into 2 groups: 40 diabetic patients received a low-protein diet (0.8 g/kg/day) and 40 were maintained on a free protein diet; similarly, 44 nondiabetic patients received a low-protein diet (0.6 g/kg/day) and 45 were maintained on a free protein diet. The investigation lasted 1 year.MAIN OUTCOME MEASURE:Renal function and nutritional status.RESULTS:At the end of the study, there were no statistically significant differences in renal function between treated and nontreated diabetic patients, whereas treated nondiabetic patients showed a lower decrease in renal function compared with the nontreated group. In both diabetic and nondiabetic patients, the mean body weight and obesity index decreased significantly in treated patients compared with nontreated ones. Serum albumin and prealbumin were stable in all patients during the whole study time, and there were no other signs of malnutrition.CONCLUSION:An adequate dietary protein restriction is accepted by patients, and it is well tolerated during a 12-month follow-up. Without any sign of malnutrition, it is possible to get near the ideal body weight and to reduce the obesity index and the body mass index, which are both well-established risk factors for developing cardiovascular pathology. In nondiabetic patients only, we observed a significant slowing of the progression of renal damage.

A 71-year-old-woman was admitted to the S. Eugenio Hospital for a history of progressively impaired standing and gait. Anamnesis revealed systemic hypertension, gastric polyposis and juvenile pulmonary tuberculosis. Neurological examination showed a severe truncal and gait ataxia, without any sensory-motor impairment. Motor and somato-sensory evoked potentials were normal. Brain Magnetic Resonance Imaging (MRI) showed minimal signs of chronic ischemia only at a supratentorial level. Cerebral Single Photon Emission Computed Tomography, spinal MRI, total body computed tomography, Esophagogastroduodenoscopy, and finally total body Positron Emission Tomography resulted negative for neoplasms. Oncological serum markers were negative. Serum antibody against Purkinje's cells (Anti-Yo) was detected and titer was 1 : 80, while normally it should be undetectable. Other autoantibodies (Anti-Hu, Anti-Ri) were undetectable. Two sessions of plasma exchange (PE) were thus performed, leading to a rapid, marked and durable improvement of standing and gait and to a reduction of the autoantibody, which became undetectable. No serious adverse effect was noted. Although no definite therapy for autommume cerebellar ataxia has been established, PE should be considered as one of the main therapeutic choices.