Aromatic L-amino acid decarboxylase deficiency: clinical features, treatment, and prognosis.
BACKGROUND
Deficiency of aromatic L-amino acid decarboxylase (AADC) is associated with severe developmental delay, oculogyric crises (OGC), and autonomic dysfunction. Treatment with dopamine agonists and MAO inhibitors is beneficial, yet long-term prognosis is unclear.


OBJECTIVE
To delineate the clinical and molecular spectrum of AADC deficiency, its management, and long-term follow-up.


RESULTS
The authors present six patients with AADC deficiency and review seven cases from the literature. All patients showed reduced catecholamine metabolites and elevation of 3-O-methyldopa in CSF. Residual plasma AADC activity ranged from undetectable to 8% of normal. Mutational spectrum was heterogeneous. All patients presented with hypotonia, hypokinesia, OGC, and signs of autonomic dysfunction since early life. Diurnal fluctuation or improvement of symptoms after sleep were noted in half of the patients. Treatment response was variable. Two groups of patients were detected: Group I (five males) responded to treatment and made developmental progress. Group II (one male, five females) responded poorly to treatment, and often developed drug-induced dyskinesias.


CONCLUSIONS
The molecular and clinical spectrum of AADC deficiency is heterogeneous. Two groups, one with predominant male sex and favorable response to treatment, and the other with predominant female sex and poor response to treatment, can be discerned.
Pons
R
R
Department of Neurology, College of Physicians and Surgeons of Columbia University, New York, NY, USA.
Ford
B
B
Chiriboga
C A
CA
Clayton
P T
PT
Hinton
V
V
Hyland
K
K
Sharma
R
R
De Vivo
D C
DC
D000293:Adolescent; D000592:Amino Acid Metabolism, Inborn Errors / Q000175:diagnosis* / Q000188:drug therapy* / Q000235:genetics; D001142:Aromatic-L-Amino-Acid Decarboxylases / Q000097:blood / Q000172:deficiency* / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D018491:Dopamine Agonists / Q000627:therapeutic use; D005260:Female; D006719:Homovanillic Acid / Q000134:cerebrospinal fluid; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000134:cerebrospinal fluid; D007223:Infant; D008297:Male; D008996:Monoamine Oxidase Inhibitors / Q000627:therapeutic use; D011379:Prognosis; D012737:Sex Factors; D016896:Treatment Outcome; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000134:cerebrospinal fluid; D025101:Vitamin B 6 / Q000627:therapeutic use
D018491:Dopamine Agonists; D008996:Monoamine Oxidase Inhibitors; D014443:Tyrosine; D006897:Hydroxyindoleacetic Acid; D025101:Vitamin B 6; D001142:Aromatic-L-Amino-Acid Decarboxylases; C008404:3-methoxytyrosine; D006719:Homovanillic Acid