[Polycythemia vera as a cause for progressive cognitive impairment].

History: A 82-years old woman was admitted with a progressive cognitive decline for further investigations and treatment.

Findings And Diagnosis: In the computed tomography of the brain findings of subcortical artherosclerotic encephalopathy (SAE) were present. Laboratory findings revealed elevated hemoglobin-levels (19.9 g/dl). In further investigations we found a mutation in JAK-2 as diagnostic sign for polycythemia vera (Pv). After specific treatment of the Pv cognition improved significantly.

Discussion: In this case report we were able to relate the progressive cognitive impairment in the context of newly diagnosed Pv in conjunction with pre-existing SAE. After Pv-directed therapy cognition improved. This case report underlines the importance of a good diagnostic work-up of patients with cognitive impairment to rule out secondary and possible treatable causes.