A case of chorea with cognitive impairment associated with polycythemia vera

Polycythemia vera (PV) is a clonal myeloproliferative disorder that is often associated with neurological symptoms. Rare manifestations of PV may include movement disorders (mainly chorea) and cognitive impairment (CI), which are fully or partially reversible with appropriate treatment. We present a case of chorea with CI in a 69-year-old man with a confirmed с1849G>T (V617F) mutation in the JAK2 gene with no vascular pathology on neuroimaging. In this patient, there is a clear correlation between the regression of the movement disorders with therapeutic phlebotomy and the start of treatment with hydroxyurea, which allows the conclusion that chorea has the secondary form. The cognitive symptoms remained at the same level after the start of treatment and during the one-year follow-up and did not develop further. In view of the patient's age, a concomitant neurodegenerative disease cannot be ruled out. In elderly patients with new-onset chorea and CI, it is therefore important to consider PV as a possible cause of these disorders, as early diagnosis of this condition allows timely initiation of effective treatment and prevention of the development of complications.