[Primary Sjögren's syndrome presenting with choreo-athetosis].

A 69-year-old man presenting with choreo-athetosis was proved to have primary Sjögren's syndrome. Choreo-athetosis suddenly appeared in the bilateral legs and the right arm; it was predominant in the right limbs. On the neurological examinations, there was no abnormal finding except for this involuntary movement. Brain MRI showed no abnormal finding. 18F-Fluorodeoxyglucose PET revealed that glucose metabolism was relatively increased in the bilateral striatum and thalamus (left side dominant). Dry eye and thirst were present for 4 years, and a diagnosis of primary Sjögren syndrome was confirmed by ophthalmological examinations, lip biopsy and sialography. Choreo-athetosis disappeared after thioridazine hydrochloride was started, while steroid was not effective.