Further observations showing the impact of the probenecid test in movement disorders.

Two patients with movement disorders are described and neurochemically studied. The first subject concerns a central anticholinergic syndrome in a 83 years old man treated with l-dopa and amantadine for red nucleus tremor. The second one is an association of parkinsonism and chorea in a 76 years old woman presenting with FAHR's syndrome. In both cases, CSF HVA levels were measured before and after oral probenecid load. The observations confirm the usefulness of this neurochemical strategy in order to classify aging patients with parkinsonism into dopasensitive and doparesistant groups.