Diabetic nephropathy is becoming the most common primary renal disease in end stage renal disease patients. The prevalence of diabetic patients in dialysis reaches even the 30% of the dialysis population (USRDS) with an incidence rate, in some countries, up to 40%. The 5 years surviving time of diabetic patients in dialysis is about the 20% and, compared to the hypertension and glomerulonephritis complications, still remains the worst. Diabetes is often associated to several comorbid factors such as hypertension, autonomic neuropathy, vasculopathy, metabolic disorders (ketoacidosis, poor glycaemic control), and electrolyte disorders. So, the diabetic patient is fragile, with a rather poor tolerance to dialysis, lack of achievement of dry body weight and inadequate dialysis. In order to gain a more detailed insight into a possible better tolerance to dialysis, arising from the elimination of acetate in dialysate bath (Acetate Free Biofiltration) and from the use of an automatic system to control the blood volume (Blood Volume Control),the investigators would like to investigate the cardiovascular stability and the frequency of intradialytic symptoms in a prospective, randomized, cross-over study.

Acetate-Free-Biofiltration (AFB) was proved to be a technique suitable to treat critical patients, such as elders and diabetics, because of frequency reduction of hypotensive episodes and symptoms during the treatment and a better control to metabolic aspects (such as metabolic acidosis).

The Blood Volume Control (BVC) is a tool, that allows to improve the cardiovascular tolerance to the treatment, especially in hypotension-prone patients, appearing promising in the correction of the arterial hypertension induced by the hydro-saline overload.

The use of BVC in AFB has been tested to verify the behaviour of the kinetics of electrolyte (in particular of bicarbonate) and it has got good results, in terms of a further improvement in treatment tolerance, for critical patients However, this therapy (AFB+BVC) was not yet evaluated as the dialysis tolerance improvement in diabetics concern, nor the relative contribution given by each factor in achieving this result.

The study, 9 months long, is aimed to verify the treatment tolerance of insulin requiring diabetic patients, by using standard bicarbonate dialysis (BD), or Acetate Free Biofiltration (AFB) and/or a Blood Volume Control(BVC). The study is divided in three phases: the first one, three months long, is the baseline in standard bicarbonate dialysis, then all the patients are shifted to AFB with BVC, for other three months, while the last three months long phase, after a randomization, has the aim to identify the relative contribution of each factor (absence of acetate in the bath or BVC) in the treatment tolerance improvement(if any). The treatment tolerance will be evaluated considering the frequency of intradialytic hypotensive events.

Inclusion Criteria:

• End stage renal disease patients
• Patients affected by diabetic nephropathy with insulin therapy, for, at least, 6 months
• Patients with renal replacement therapy with haemodialysis three time a week, for, at least, 6 months.
• Age between 18 and 85 years

Exclusion Criteria:

• Patients affected by neoplasm and/or mental illness
• Patients with residual diuresis > 500 ml/die;
• Patients in single needle bicarbonate dialysis.