Alterations in plasma amino acid levels in children with asthma: a preliminary investigation.

Concentrations of plasma amino acids and cortisol were measured in 27 children with status asthmaticus, moderate, or mild asthma and in 7 controls without lung disease. Individuals with conditions potentially altering amino acid levels were excluded. Measurements were made at 8 A.M. and 4 P.M. on the same day. Of the 24 amino acids analyzed, threonine, serine, citrulline, tyrosine, proline, alanine, cystine, isoleucine, ornithine, lysine, and arginine were decreased at 8 A.M. or 4 P.M. and plasma cortisol was elevated at 4 P.M. in patients with status asthmaticus when compared with the other groups (p less than 0.05). Normal diurnal variations of amino acids and cortisol were preserved in all groups. Sequential daily determinations in eight patients with status asthmaticus showed progressive increases in total and many individual amino acids as symptoms subsided. These studies demonstrate a decrease of certain gluconeogenic amino acids in the plasma in status asthmaticus. This diminution could reflect the need for maintenance of normal glucose concentrations in status asthmaticus. The decrease in gluconeogenic amino acid levels may play a role in the severity of asthma.