Paroxysmal exercise‐induced dyskinesia without involuntary movements

A 66‐year‐old British man was referred to our department because of a 2.5 year history of bilateral paroxysmal weakness of the lower limbs. It occurred when he walked for about 10 minutes, so he would stop in place and spontaneously rest for up to 15 minutes. When carbamazepine 200 mg/day was administered, the severity and frequency of the symptoms reduced by half and resolved when the dose was increased to 300 mg/day. Even if no involuntary movement is observed, paroxysmal exercise‐induced dyskinesia should be considered in patients with paroxysmal painless gait disturbance, and a therapeutic trial of anticonvulsants may be helpful.
Paroxysmal dyskinesias are a group of movement disorders characterized by attacks of hyperkinesia, which include combinations of dystonia, choreoathetosis, and ballism with intact consciousness. There are different subtypes of paroxysmal dyskinesias that include paroxysmal exercise‐induced dyskinesia (PED), paroxysmal kinesigenic dyskinesia (PKD), paroxysmal non‐kinesigenic dyskinesia (PNKD), and paroxysmal hypnogenic dyskinesia (PHD). Even if no involuntary movement is observed, paroxysmal exercise‐induced dyskinesia should be considered in patients with paroxysmal painless gait disturbance, and a therapeutic trial of anticonvulsants may be helpful.