Polycythemia vera

Definition

Polycythemia vera is an abnormal increase in blood cells (primarily red blood cells) resulting from excess production by the bone marrow.

Causes, incidence, and risk factors

Polycythemia vera is an acquired disorder of the bone marrow that causes the overproduction of all three blood cell lines: white blood cells, red blood cells, and platelets.

It is a rare disease that occurs more frequently in men than women, and rarely in patients under 40 years old. It is not known what causes polycythemia vera.

The disease usually develops slowly, and most patients do not experience any problems related to the disease after being diagnosed. However, the abnormal bone marrow cells may begin to grow uncontrollably in some patients leading to acute myelogenous leukemia.

Patients with polycythemia vera also have an increased tendency to form blood clots that can result in strokes or heart attacks. Some patients may experience abnormal bleeding because their platelets are abnormal.

Symptoms

• Headache
• Dizziness
• Itchiness, especially following a warm bath
• Fullness in the left upper abdomen
• Red coloration, especially of the face
• Shortness of breath
• Breathing difficulty when lying down
• Symptoms of phlebitis

Note: Symptoms are due to increased blood viscosity (thickness) and clotting.

Additional symptoms that may be associated with this disease:

• Vision abnormalities
• Skin spots, red
• Bluish skin discoloration
• Fatigue

Signs and tests

• A CBC with differential
• Hematocrit, elevated
• White blood count, elevated
• Platelet count, elevated
• Bone marrow biopsy
• Vitamin B-12 level
• Chemistry panel
• Blood volume, increased

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

• Lactate dehydrogenase
• Urinalysis
• Serum uric acid
• TIBC
• RBC count
• Platelet aggregation test
• Leukocyte alkaline phosphatase
• Hemoglobin
• ESR
• Erythropoietin

Treatment

The objective of treatment is to reduce the high blood viscosity (thickness of the blood) due to the increased red blood cell mass and to prevent hemorrhage and thrombosis.

Phlebotomy is one method used to reduce the high blood viscosity. In phlebotomy, 1 unit (pint) of blood is removed weekly until the hematocrit is less than 45, then phlebotomy is continued as necessary.

Occasionally, chemotherapy may be given to suppress the bone marrow. Other agents such as interferon may be given to lower blood counts. Anegrelide may be given to lower platelet counts.

The use of anti-platelet therapy (such as aspirin) is controversial because it may cause stomach bleeding.

Allopurinol is given for hyperuricemia (gout).

Expectations (prognosis)

Polycythemia vera usually develops slowly, and most patients treated appropriately do not experience any problems related to the disease. However, the abnormal bone marrow cells may begin to grow uncontrollably leading to acute myelogenous leukemia. This occurs in a minority of cases.

Patients with polycythemia vera also have an increased tendency to form blood clots that can result in strokes or heart attacks. Some patients may experience abnormal bleeding because their platelets are abnormal.

Complications

• Thrombosis (a cause of stroke or heart attack)
• Peptic ulcer disease
• Gastric bleeding
• Gout
• Leukemia
• Heart failure
• Myelofibrosis

Calling your health care provider

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

Illustrations

Waldenstroms

Page Content:

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 ; polycythemia rubra vera; disorder myeloproliferative; chronic disorder myeloproliferative; condition disease disorder myeloproliferative; bone disorder marrow myeloproliferative; oslers disease