Clinical and biochemical features of aromatic L-amino acid decarboxylase deficiency.

Abstract

OBJECTIVE:

To describe the current treatment; clinical, biochemical, and molecular findings; and clinical follow-up of patients with aromatic l-amino acid decarboxylase (AADC) deficiency.

METHOD:

Clinical and biochemical data of 78 patients with AADC deficiency were tabulated in a database of pediatric neurotransmitter disorders (JAKE). A total of 46 patients have been previously reported; 32 patients are described for the first time.

RESULTS:

In 96% of AADC-deficient patients, symptoms (hypotonia 95%, oculogyric crises 86%, and developmental retardation 63%) became clinically evident during infancy or childhood. Laboratory diagnosis is based on typical CSF markers (low homovanillic acid, 5-hydroxyindoleacidic acid, and 3-methoxy-4-hydroxyphenolglycole, and elevated 3-O-methyl-l-dopa, l-dopa, and 5-hydroxytryptophan), absent plasma AADC activity, or elevated urinary vanillactic acid. A total of 24 mutations in the DDC gene were detected in 49 patients (8 reported for the first time: p.L38P, p.Y79C, p.A110Q, p.G123R, p.I42fs, c.876G>A, p.R412W, p.I433fs) with IVS6+ 4A>T being the most common one (allele frequency 45%).

CONCLUSION:

Based on clinical symptoms, CSF neurotransmitters profile is highly indicative for the diagnosis of aromatic l-amino acid decarboxylase deficiency. Treatment options are limited, in many cases not beneficial, and prognosis is uncertain. Only 15 patients with a relatively mild form clearly improved on a combined therapy with pyridoxine (B6)/pyridoxal phosphate, dopamine agonists, and monoamine oxidase B inhibitors.

• Authors: L Brun, L H Ngu, W T Keng, G S Ch'ng, Y S Choy, W L Hwu, W T Lee, M A A P Willemsen, M M Verbeek, T Wassenberg, L Régal, S Orcesi, D Tonduti, P Accorsi, H Testard, J E Abdenur, S Tay, G F Allen, S Heales, I Kern, M Kato, A Burlina, C Manegold, G F Hoffmann, N Blau
• Journal: Neurology (Neurology) Vol. 75 Issue 1 Pg. 64-71 (Jul 06 2010) ISSN: 1526-632X [Electronic] United States
• PMID: 20505134 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• Neurotransmitter Agents
• Aromatic-L-Amino-Acid Decarboxylases

Topics

• Adolescent
• Aromatic-L-Amino-Acid Decarboxylases (cerebrospinal fluid, deficiency)
• Biomarkers (cerebrospinal fluid)
• Child
• Child, Preschool
• Follow-Up Studies
• Humans
• Infant
• Neurotransmitter Agents (cerebrospinal fluid, deficiency)
• Young Adult