Polycythaemia Vera (PV) is a Rare Disease of the blood-building cells in the bone marrow primarily resulting in a chronic increase of red blood cells (erythrocytes), thereby decreasing the flowability of blood. Circulatory disorders such as thrombosis and embolism are possible consequences.
With proper treatment, the majority of patients with Polycythaemia Vera have a near-normal life expectancy.
The cause of Polycythaemia Vera is still unknown. The disorder is usually contracted but, in rare cases, it can be inherited. It is typically characterized by an increase in the production of red blood cells (erythrocytes). Patients with PV are often symptom-free at the time of diagnosis.
At the onset of the disorder, the signs and symptoms tend to be unspecific. A noticeable reddening of the face can give the impression that the affected person is actually very healthy. When the red blood cell count reaches a critical number, the flowability of the blood decreases leading to restricted blood circulation. This causes a blue coloration of the skin (cyanosis).
Other symptoms may include:
The most common complications are a result of the high viscosity (resistance to flow) of the blood, which can lead to blood clots (thrombosis). Clogging of both small and large blood vessels (embolism) can also occur.
Both the number of platelets and their function are responsible for the balance of the coagulation system. Hypercoagulation results in blood clotting, while lack of coagulation results in bleeding (e.g. skin, gastrointestinal tract).
Petrides PE. CMPE 2016 "Aktuelle Empfehlungen zur Diagnostik und Therapie Chronisch MyeloProliferativer Erkrankungen, 5. Auflage 80 Seiten, München 2016.