Aromatic L-amino acid decarboxylase deficiency: diagnostic methodology

Clin Chem. 1992 Dec;38(12):2405-10.

Abstract

Aromatic L-amino acid decarboxylase (EC. 4.1.1.28) deficiency is a newly described inborn error of metabolism that affects serotonin and dopamine biosynthesis. The major biochemical markers for this disease are increases of L-dopa, 3-methoxytyrosine, and 5-hydroxytryptophan in urine, plasma, and cerebrospinal fluid together with decreased cerebrospinal fluid concentrations of homovanillic acid and 5-hydroxyindoleacetic acid. In addition, concentrations of vanillactic acid are increased in the urine. Specific HPLC and gas chromatography-mass spectrometry methods are described that permit the identification and measurement of these metabolites in the above body fluids. Simplified assays for human plasma L-dopa decarboxylase and liver L-dopa and 5-hydroxytryptophan decarboxylase, used to demonstrate the enzyme deficiency, are also reported.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5-Hydroxytryptophan / blood
  • 5-Hydroxytryptophan / cerebrospinal fluid
  • 5-Hydroxytryptophan / urine
  • Aromatic-L-Amino-Acid Decarboxylases / deficiency*
  • Aromatic-L-Amino-Acid Decarboxylases / metabolism
  • Child
  • Child, Preschool
  • Chromatography, High Pressure Liquid
  • Dopa Decarboxylase / blood
  • Dopa Decarboxylase / metabolism
  • Gas Chromatography-Mass Spectrometry
  • Homovanillic Acid / analogs & derivatives
  • Homovanillic Acid / cerebrospinal fluid
  • Homovanillic Acid / urine
  • Humans
  • Hydroxyindoleacetic Acid / cerebrospinal fluid
  • Infant
  • Levodopa / blood
  • Levodopa / cerebrospinal fluid
  • Levodopa / urine
  • Liver / enzymology
  • Metabolism, Inborn Errors / diagnosis*
  • Reference Values
  • Tyrosine / analogs & derivatives
  • Tyrosine / blood
  • Tyrosine / cerebrospinal fluid
  • Tyrosine / urine

Substances

  • vanillactic acid
  • Tyrosine
  • Levodopa
  • Hydroxyindoleacetic Acid
  • 5-Hydroxytryptophan
  • Dopa Decarboxylase
  • Aromatic-L-Amino-Acid Decarboxylases
  • 3-methoxytyrosine
  • Homovanillic Acid