ABSTRACT
A 9-year-old girl with hereditary dibasicaminoaciduria has been studied for three years. Initially, clinical features were: growth failure; anorexia and aversion to protein, spontaneous daily protein intake averaging only 10 gm; fasting and postprandial venous hyperammonemia; subnormal plasma concentrations of lysine, arginine, ornithine, and citrulline, with generalized hypermonobasicaminoacidemia; abnormally high renal clearances of lysine, arginine, and ornithine; and intestinal malabsorption of lysine and arginine. Intestinal absorption of citrulline, a precursor of arginine and ornithine, was normal. The patient was observed during four sequential 6-month periods as follows: no treatment (Period I); dietary supplement of arginine and lysine (Period II); dietary supplement of citrulline and lysine (Period III); no treatment (Period IV). During Periods II and III growth rate increased 3- to 4-fold, spontaneous protein intake increased 2- to 3-fold, and abnormalities in blood NH3 and the plasma aminogram were partially corrected. In most respects the citrulline plus lysine supplement was more beneficial than that of arginine plus lysine.
Subject(s)
Amino Acid Metabolism, Inborn Errors/drug therapy , Ammonia/blood , Arginine/therapeutic use , Citrulline/therapeutic use , Growth Disorders/drug therapy , Lysine/therapeutic use , Child , Female , HumansABSTRACT
Immature male albino rats (70-80 g), eating a diet furnishing all nutrients for optimal growth and containing 84.6 mumoles of leucine/g, gained weight at an average rate of 5.9 g/day. Removal of leucine caused an average daily weight loss of 1.3 g. Addition of leucine to the diet in graduated amounts corrected this weight loss, the improvement in body weight (BW) being proportional to the dietary content of leucine. Addition of alpha-ketoisocaproic acid in place of leucine to the leucine-free diet also prevented loss of BW. Percentage efficiency of alpha-ketoisocaproic acid as a dietary substitute for leucine was calculated as: (see article). Efficiency of such substitution varied from 27% for a diet containing 84.6 mumoles of alpha-ketoisocaproic acid/g to 20% for a diet containing 169.2 alpha-ketoisocaproic acid/g.
