Polycythemia vera is a proliferative disorder where the bone marrow overproduces red blood cells, white blood cells, and platelets. It is caused by a mutation in the JAK2 enzyme. Common symptoms include headache, dizziness, and an enlarged spleen due to spleen enlargement and increased blood viscosity. Treatment focuses on phlebotomy to reduce red blood cell counts and medications like hydroxyurea to suppress bone marrow production and reduce risk of blood clots. Patients also need lifestyle changes and monitoring for complications like thrombosis.

1. Polycythemia vera

2. DEFINITION:
– Polycythaemia vera, or primary polycythaemia, is a proliferative disorder
in which the bone marrow is hypercellular, and the erythrocyte, leucocyte
and platelet counts in the peripheral blood are elevated.
– However, erythrocyte elevation predominates; the haematocrit can exceed
60%. This phase can last for an extended period of 1 0 to 20 years or
longer.

3. Incidence
– The estimated incidence of polycythaemia vera is 2 per 1
00,000 people and the median age at onset is 65 years.

4. Types
– Polycythemia can be divided into two categories:
– Primary polycythemia: In primary polycythemia the increase in red blood
cells is caused by inherent problems in the process of red blood cell
production.
• Secondary polycythemia: Secondary polycythemia generally occurs as a
response to other factors or underlying conditions that promote red blood
cell production.

5. Cause
– The mutation of the enzyme JAK2
causes an erythrocyte hypersensitivity
to the effects of erythropoietin.
– Although mutation in JAK2 is found in
the majority of people with
polycythaemia vera.
– spleen resumes its embryonic function
of haematopoiesis and enlarges.
– Eventually, the bone marrow may
become fibrotic, with a resultant
inability to produce as many cells ('bu
rnt out' or spent phase).

6. Clinical manifestations
– Patients typically have a ruddy complexion and splenomegaly (enlarged spleen).
– The symptoms result from the increased blood volume (headache, dizziness,
tinnitus, fatigue, paraesthesias
– and blurred vision) or from increased blood viscosity
– angina, claudication, dyspnoea and thrombophlebitis particularly, if the patient
has atherosclerotic blood vessels.
– Elevated blood pressure
– Uric acid may be elevated, resulting in gout and renal stone formation.

7. – .
– bothersome problem is generalised pruritus, which may be caused by
histamine release due to the increased number of basophils.
– Erythromelalgia, a burning sensation in the fingers and toes

9. Assessment and diagnostic findings
– elevated erythrocyte mass (anuclear medicine procedure), a normal oxygen
saturation level and an enlarged spleen.
– elevated haematocrit; it is normal or only slightly low.
– CBC
– other haematological disorders (ET and myelofibrosis) also have this mutation
– PBS
– Bone biopsy

12. Complications
– increased risk of thromboses resulting in a brain attack or stroke or heart attack
(Ml);
– thrombotic complications are the most frequent cause of death.
– Bleeding is also a complication, platelets (often very large)
– nosebleeds,
– ulcers,
– frank GI bleeding
– haematuria
– intracranial haemorrhage.

13. Medical management
– The objective of management is to reduce the high blood cell mass.
– Phlebotomy is an important part of therapy.
– initially 500 ml once or twice weekly to reduce blood viscosity and
deplete the patient's iron stores.
– routine phlebotomy on an intermittent basis, with the target of
maintaining the haematocrit less than 45%.
– In higher-risk patients, chemotherapeutic agents (e.g. hydroxyurea)
can be used to suppress marrow function

14. – hydroxyurea (to lower incidence of thrombotic complications)
– Low-dose aspirin decreases the risk of significant throm botic
complications (DVT, pulmonary em bolism, Ml)
– Aspirin is also useful in reducing the pain associated with erythromyalgia.
– Interferon alfa-2b (l ntron-A) is the most effective treatment for managing
the pruritus.
– Allopurinol is used to prevent gouty attacks in patients with elevated uric
acid concentrations.
– Antihistamines

15. Nursing management
– Encourage patient to quit smoking,
– Maintain weight. (BMI)
– Assess for poorly controlled hypertension and diabetes
– Assess for the signs and symptoms of thrombosis.
– Advise to avoid aspirin and aspirin-containing medications, if a history of significant
bleeding is present.
– Instruct to avoid iron supplements, including those within multivitamin supplements,
– For pruritus, recommend bathing in tepid or cool water and using soap alternatives
such as Pinetarsol and oatmeal-based creams.