Paroxysmal dystonia as a manifestation of multiple sclerosis

Paroxysmal dystonia is a rare manifestation of multiple sclerosis (MS).

A 41-year-old man presented to our Emergency Department with sudden and repeated episodes of left upper limb flexion and lower limb extension. His medical history included an episode of left facial palsy a year earlier. Neurological examination demonstrated only brisk deep tendon reflexes on the left upper limb. Routine blood and urine analyses were normal. Computed tomography of the brain and cervical Doppler were normal. Aspirin and sodium valproate were started, without improvement. Video-EEG monitoring revealed no electrographic abnormality synchronous with these paroxysmal events, excluding epileptic nature. Cerebral magnetic resonance imaging showed multiple T2 white matter lesions at the midbrain, right diencephalon, corpus callosum, cervical, and thoracic spinal cord. The right diencephalic lesion enhanced with gadolinium. Complete basic and immunologic analysis and serological studies were normal or negative. Oligoclonal bands were positive in cerebrospinal fluid (negative in serum). Methylprednisolone (1 g/d for 5 d) was started without clinical improvement. Carbamazepine (400 mg/d) was promptly effective, and discontinued after 1 month without recurrence.

The patient met the criteria for the diagnosis of MS according to the 2010 McDonald criteria. The timely and accurate diagnosis of MS requires the recognition of its varied and atypical clinical manifestations.