[Type I glutaric aciduria: an unrecognized cause of progressive dystonia].

BACKGROUND

Glutaric acidemia type I is one of the least rare organic acidemias. The number of diagnosed causes is however still low because the presentation is variable and often confusing. The disease may sometimes have a slowly progressive course. Typically, it presents in infancy, mimicking acute encephalitis, leaving a previously healthy child severely handicapped with generalized dystonia, spastic quadriplegia or choreoathetosis. Cerebral MRI shows large CSF-containing spaces (sylvian fissures and anterior to the temporal lobes) and basal ganglia abnormal signal.

METHODS

An eight year-old boy had begun at 18 months with motor difficulties and abnormal posture of upper and lower left limbs. When examined, he had generalized dystonia more pronounced at the left side, severe dysarthria and tongue dystonia. IQ was normal. MRI showed high T2 signal in basal ganglia and enlarged CSF containing spaces. Urinary organic acids chromatography confirmed glutaric acidemia type I. Two of his sisters deceased before the age of two years with a clinical picture of fever, seizures and hypotonia. Another sister had the same symptoms at the same age. She lived until 10 year with severe quadriplegia.

CONCLUSIONS

Our observation shows variability of clinical picture and course of glutaric acidemia type I in the same kindred. We propose systematic organic acides chromatography in all children with acute or progressive dystonia with basal ganglia abnormalities on MRI. This seems an imperative attitude because appropriate diet could slow the progression of the illness.