To evaluate the effect on phosphatemia in hemodialysis patients of replacing the meat or fish included in two meals a week with an amount of egg white containing the same quantity of proteins.

Hyperphosphatemia develops in the majority of patients with end-stage renal disease (ESRD). It is responsible for severe complications such as mineral bone disease, and has a role in worsening the cardiovascular mortality of dialyzed patients. Therefore, a close control of serum phosphorus remains a cornerstone in the clinical management of dialyzed patients to improve their long term prognosis. There are multiple sources of phosphorus in the diet that could be the target of such a dietary intervention but, because of important differences in bioavailability, they are not all equally relevant in influencing phosphatemia. Among them animal proteins that have a bioavailability of about 60% represent an important target for phosphate-lowering nutritional interventions. However, lowering the protein content of the diet in hemodialysis (HD) patients may be dangerous because it may increase the the risk of malnutrition hence worsening their prognosis. In the present study we intend to explore an alternative strategy to lower the intake of phosphate with animal proteins by replacing the meat or fish included in two meals a week with egg white that is reach of proteins but has virtually no phosphate.

Inclusion Criteria:

• thrice weekly 4 h standard bicarbonate HD treatment with an at least 6-month vintage
• stable dialysis dose and modality at least by 3 months
• hyperphosphataemia (serum phosphate ≥5.0 mg/dl) at least by 3 months
• stable dietary intake at least by 3 months
• stable body weight at least by 3 months
• stable biochemical markers at least by 3 months

Exclusion Criteria:

• diabetes
• liver disease
• malignancy
• previous parathyroidectomy
• psychiatric diseases
• non-collaborative patients