Movement disorders associated with chronic GM2 gangliosidosis. Case report and review of the literature.

A 24-year-old man presented with dystonia, dementia, amyotrophy, choreoathetosis, and ataxia. Partial hexosaminidase A deficiency was documented in serum and leukocytes and confirmed by rectal biopsy with ganglion cells containing membranous cytoplasmic bodies. A brief review of the literature reveals that tremor, dystonia and choreoathetosis are common but neglected symptoms associated with chronic GM2 gangliosidosis.