Early-onset cerebellar ataxia with retained tendon reflexes.

The authors report a clinical review of 16 childhood cases with early-onset cerebellar ataxia with retained tendon reflexes. The preservation of tendon reflexes distinguishes this disorder from Friedreich's ataxia. The mean age of onset of symptoms was 7.1 years. The main presenting symptom was abnormal gait (100%). Ataxia of gait and limbs and normal or increased tendon reflexes were found in all cases. This disorder is associated with dysarthria, pyramidal signs in the limbs, and in some instances, sensory loss. Other important differences from Friedreich's ataxia are absence of optic atrophy, diabetes mellitus, cardiomyopathy and severe skeletal deformity. Sensory nerve conduction was found to be normal, excluding one case. This finding constitutes another aspect of the syndrome different from Freidreich's ataxia. CT scans were normal in 2 of the 4 cases. The remaining two cases showed cerebellar atrophy. Inheritance is probably autosomal recessive in the majority of cases.