The effects on growth, body composition, and metabolism of a protein-restricted 
diet supplemented with essential aminoacids, the calcium-ketoacids of valine, 
leucine, isoleucine, and phenylalanine, and the calcium-hydroxyacid of 
methionine, were investigated in seven growth-retarded children with chronic 
renal failure. During 0.4 to 1.0 years of treatment there were significant 
increases in growth velocity and upper arm circumference SD scores, body cell 
mass (intracellular water calculated as tritium space minus corrected sodium 
bromide space) and serum transferrin. Blood urea and urea:creatinine ratio fell 
in all children. Renal function assessed from plasma creatinine and 51Cr EDTA 
clearance did not change significantly. During treatment there was an increase 
in plasma calcium, high levels necessitating brief interruption of therapy in 
two children, and a decrease in plasma phosphate. Levels of serum parathormone 
fell in all children, and were correlated inversely with plasma calcium and 
positively with plasma phosphate. Abnormalities compared to control children in 
blood aminoacid and branched-chain ketoacid levels were unaffected by treatment. 
These results suggest that a protein-restricted diet supplemented with essential 
aminoacids and calcium-keto and hydroxyacids may be useful to improve linear 
growth and nutritional status in children with chronic renal failure, and that a 
reduction in hyperparathyroidism may be partly responsible for some of the 
beneficial effects observed.