Polycythemia vera

Polycythemia vera is a disorder of the bone marrow. It mainly causes too many red blood cells to be produced. The numbers of white blood cells and platelets may also be higher than normal.

This is a rare disorder that occurs more often in men than in women. It is not usually seen in people under age 40. The problem is often linked to a gene defect called JAK2V617F. The cause of this gene defect is unknown.

Symptoms may include any of the following:

• Trouble breathing when lying down
• Dizziness
• Excess bleeding
• Full feeling in the left upper abdomen (due to enlarged spleen)
• Headache
• Itchiness, especially after a warm bath
• Red skin coloring, especially of the face
• Shortness of breath
• Symptoms of blood clots in veins near the skin surface (phlebitis)

Other symptoms that may occur with this disease:

• Bluish skin color
• Fatigue
• Red skin spots
• Vision problems

The health care provider will perform a physical exam. You may also have the following tests:

• Bone marrow biopsy
• Complete blood count with differential
• Comprehensive metabolic panel
• Erythropoietin level
• Genetic test for the JAK2V617F mutation
• Oxygen saturation of the blood
• Red blood cell mass
• Vitamin B12 level

This disease may also affect the results of the following tests:

• ESR
• Lactate dehydrogenase (LDH)
• Leukocyte alkaline phosphatase
• Platelet aggregation test
• Serum uric acid

The goal of treatment is to reduce the thickness of the blood and prevent bleeding and clotting problems.

A method called phlebotomy is used to decrease blood thickness. One unit of blood (about 1 pint) is removed each week until the number of red blood cells drops. The treatment is continued as needed.

Medicines that may be used include:

• Hydroxyurea to reduce the number of red blood cells made by the bone marrow. This drug may be used when the numbers of other blood cell types are also high.
• Interferon to lower blood counts.
• Anagrelide to lower platelet counts
• Ruxolitinib (Jakafi) to reduce the number of red blood cells and reduce an enlarged spleen. This drug is prescribed when hydroxyurea and other treatments have failed.

Taking aspirin to reduce the risk of blood clots may be an option for some people. But, aspirin increase the risk of stomach bleeding.

Ultraviolet-B light therapy can reduce the severe itching some people experience.

The disease usually develops slowly. Most people do not have symptoms related to the disease at the time of diagnosis. The condition is often diagnosed before severe symptoms occur.

Complications may include:

• Acute myelogenous leukemia (AML)
• Bleeding from the stomach or other parts of the intestinal tract
• Gout
• Heart failure
• Myelofibrosis
• Thrombosis (blood clotting, which can cause a stroke, heart attack, or other body damage)

Call your health care provider if symptoms of polycythemia vera develop.

Primary polycythemia; Polycythemia rubra vera; Myeloproliferative disorder; Erythremia; Splenomegalic polycythemia; Vaquez's disease; Osler's disease; Polycythemia with chronic cyanosis - Myelopathic polycythemia; Erythrocytosis megalosplenica; Cryptogenic polycythemia

Kremyanskaya M, Najfeld V, Mascarenhas J, Hoffman R. The polycythemias. In: Hoffman R, Benz EJ Jr, Silberstein LE, Heslop HE, Weitz JI, Anastasi J, eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 67.

National Cancer Institute: PDQ Chronic Myeloproliferative Neoplasms Treatment: Polycythemia Vera. Bethesda, MD: National Cancer Institute. Date last modified December 3, 2014. Available at: www.cancer.gov/cancertopics/pdq/treatment/myeloproliferative/HealthProfessional/page3. Accessed March 3, 2015.

Tefferi A. Polycythemia vera, essential thrombocythemia, and primary myelofibrosis. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 166.

Updated by: Rita Nanda, MD, Assistant Professor of Medicine, Section of Hematology/Oncology, University of Chicago Medicine, Chicago, IL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.