Neuroaxonal dystrophy. Juvenile form.
Incidence
A few cases have been reported.
Clinical Characteristics
The symptoms are usually severe polymyoclonus and cerebellar ataxia. Dysarthria is also present. Deep tendon reflexes are absent in lower limbs, which are hypotonic, without evidence of pyramidal signs. Patients may have generalized seizures, and polymyoclonus are increased in severity. Often, these polymyoclonus may be activated by minimal voluntary movements but not by sound or visual stimulation. Slow decline in intellectual function may occur. EEG shows paroxysms of irregular delta activity. Pathologically there is typical spheroids of multiple membranous lamellae in central nervous system. Patient may have generalized extrapyramidal rigidity, choreoathetosis and tremor. Dystonic movements may be present. Abnormal optokinetic nystagmus. CT scan is normal.
Precipitants
no
Provocation Tests
no. Often, these polymyoclonus may be activated by minimal voluntary movements.
Diagnostic Procedures
Pathologically there is typical spheroids of multiple membranous lamellae in central nervous system.