Chorea can result from many causes, and the diagnostic workup can be challenging. Although often accompanied by other extrapyramidal symptoms, hydrocephalus has not been mentioned as a possible cause of chorea to date. Here we report an unusual case of chorea secondary to normal pressure hydrocephalus, which clearly improved after shunt placement. Hydrocephalus may cause extrapyramidal symptoms, which are most likely a result of pressure on tracts of the nigrostriatal pathway or the cortico-striato-pallido-thalamo-cortical circuit. Apparently, hydrocephalus induced pressure may occasionally also compromise the caudate nucleus which lies immediately adjacent to the enlarged ventricles, resulting in chorea. We suggest that clinicians should be more alert to hydrocephalus as a rare but reversible cause of chorea.

Normal pressure hydrocephalus (NPH) typically presents with the triad of cognitive deterioration, abnormal gait and urinary incontinence. Additional akinetic or tremulous movements may result from both idiopathic and secondary NPH. In contrast, hyperkinetic movements other than tremor have not been reported to result from hydrocephalus. When present, such hyperkinetic movements in NPH were exclusively observed secondary to causes not related to the hydrocephalus.1 Indeed, secondary chorea has been described to result from a variety of causes, but not from hydrocephalus.2

Here we report a case of NPH induced chorea, which completely resolved after shunt placement. We will briefly discuss the pathophysiological mechanisms underlying movement disorders …