Polycythemia vera presenting with left hemichoreiform movements

A 65-year-old man developed abruptly choreiform movements involving the left face, arm and leg one day prior to admission. Physical examination revealed red face and palms, hyperemic conjunctivae and atrial fibrillations. Blood pressure was 168/90. Spleen was not palpable. Hemichoreiform movements of the left face and limbs were observed. There was no other neurological abnormalities. Laboratory studies showed RBC 880x104, Hb 22.4g/dl, Hct 63%, WBC 8,100, platelets 22.9x104, ESR 0mm/hr, RBC oxygen saturation 97%, serum iron 67 μg/dl, LDH 593 units, uric acid 14mg/dl, and erythropoietine (HI method) 19mIU/ml (normal 28-88). Bone marrow showed myeloid nucleated cell count 38.6x104. ECG showed atrial fibrillations. Chest X-ray and scintigrams of liver and spleen were normal. CSF was normal. Brain CT scan on admission disclosed a low density area in right caudate nucleus. The choreiform movements were rapidly mitigated by venesection and by oral administration of haloperidol(3mg daily). There weeks after discontinuing haloperidol, the hemichorea returned. The routine hematology showed RBC 870x104, Hb 19.8g/dl, Hct 62%, WBC 10,200, and plateret 37.4x104. Another venesection reduced the chorea. Pipobroman was administered to control the polycythemia vera. He has been free of choreic movements thereafter. Choreiform movement is rarely observed in polycythemia vera. The pathogenesis is still unknown. The venous congestion, however, may play a role in this case because the choreic movements disappeared by venesection. (author)