Hemichorea caused by polycythemia vera

Polycythaemia vera (PV) is a chronic myeloproliferative disorder. PV should be suspected with hemoglobin >10.2/9.9 mmol/L (m/f) and/or PV-related features (aquagenic pruritus, erythromelalgia, atypical thrombosis, splenomegaly, thrombocytosis or leukocytosis). This case report highlights the connection between PV and neurological manifestations, including rare symptoms like chorea. An 82-year-old woman presented with sudden choreiform movements, dysarthria, and behavioral changes. Investigations ruled out primary neurological disease and confirmed PV. With treatment, the neurological symptoms resolved.