Type of metabolic disorder: cerebral organic aciduria
Deficiency: glutaryl-CoA dehydrogenase
Gene: GCDH
Chromosome: 19p13.2
Affected: catabolism of L-lysine, L-hydroxylysine and L-tryptophan
Accumulations: glutaric acid, 3-hydroxyglutaric acid, glutaconic acid and glutaryl carnitine
Inheritance: autosomal recessive
Clinical features:
(1) repeated episodes of acute encephalopathy during childhood triggered by infection or surgery
(2) febrile reaction to vaccination
(3) dystonic movement disorder secondary to striatal injury during encephalopathic episodes
(4) variable delayed motor development
Patients may be subclassified based on urinary excretion of the metabolites:
(1) low excreters: associated with some residual enzyme activity (associated with missense mutations)
(2) high excreters: little residual enzyme activity
Diagnosis is based on identifying disease-causing mutations or low GCDH enzyme activity.
