Decreased ventricular fluid norepinephrine metabolite in childhood-onset dystonia.

3-methoxy-4-hydroxyphenylglycol (MHPG), the primary brain metabolite of norepinephrine (NE), was measured in ventricular fluid from 51 patients with dystonia, other movement disorders, or hydrocephalus. The dystonic patients were divided into three categories: childhood-onset form with early limb dystonia and rapid progression to generalized symptoms, more localized and benign adult-onset dystonia, and symptomatic dystonia. Patients with the childhood form had significantly lower ventricular fluid MHPG levels (8.7 +/- 0.6 ng per milliliter) than other dystonic patients (11.4 +/- 1 ng per milliliter), age-matched controls with neurologic disease (11.7 +/- 1.1 ng per milliliter), or other movement disorders (11.8 +/- 0.7 ng per milliliter). Decreased ventricular fluid MHPG levels suggest a possible abnormality of brain NE function in childhood dystonia.