According to the hyperfiltration theory of renal diseases characterized by a decrease in the number of functional nephrons, increased arterial blood pressure, excessive protein intake in the diet, high levels of calcium (Ca) and phosphorus (P), secondary hyperparathyroidism, hypertriglyceridemia and/or hypercholesterolemia, proteinuria and metabolic acidosis are some factors that impair the prognosis of the disease. The amount of protein in the diet is the most important of these factors. A protein-restricted diet administered to patients with chronic renal failure results in the risk of inadequate amino acid intake. To overcome this problem, the use of dysaminated alpha-keto analogues has been considered to reduce the risk of nitrogenemia resulting from the continuous intake of essential amino acids. Currently, the necessity of essential amino acids even in adult patients with chronic renal failure is controversial; besides, trials on the use of these amino acids in pediatric patients are scarce. The aim of this study is to investigate the efficacy and applicability of conservative therapy with a protein-restricted diet supplemented with keto acids in the management of chronic renal insufficiency or failure.