Polycythemia vera is a blood disorder in which your bone marrow makes too many red blood cells. Polycythemia vera also may result in production of too many of the other types of blood cells — white blood cells and platelets. But it's the excess red blood cells that thicken your blood and cause most of the concerns associated with polycythemia vera.
Polycythemia vera — also called primary polycythemia — is rare and usually develops slowly. You may have it for years without noticing signs or symptoms. Often, polycythemia vera is found during a blood test done for some other reason.
Without treatment, polycythemia vera can be life-threatening. However, with proper medical care, many people experience few problems related to this disease.
In its early stages, polycythemia vera usually doesn't cause any signs or symptoms. However, as the disease progresses, you may experience:
When to see a doctor
Because polycythemia vera causes your blood to thicken and slows blood flow, it increases your risk of developing blood clots. If a blood clot occurs in your head, it can cause a stroke. Seek emergency medical care if you have any of the following signs or symptoms of a stroke:
Polycythemia vera occurs when a mutation in a bone marrow cell causes a problem with blood cell production. Normally, your body carefully regulates the number of each of the three types of blood cells you have. But in polycythemia vera, the mechanism your body uses to control the production of blood cells becomes impaired, and your bone marrow makes too many of some blood cells.
The mutation that causes polycythemia vera is thought to affect a protein switch that tells the cells to grow. Specifically, it's a mutation in the protein JAK2 (the JAK2 V617F mutation). Most people with polycythemia vera have this mutation. Doctors and researchers don't yet understand the full role of this mutation and its implications for treating the disease.
It's not clear what causes the mutation that leads to polycythemia vera. Researchers believe the mutation occurs after conception — meaning that your mother and father don't have it — so it's acquired, rather than inherited from a parent.
Factors that may increase your risk of developing polycythemia vera include:
Possible complications of polycythemia vera include:
Preparing for your appointment
Start by seeing your family doctor or a general practitioner if you have any signs or symptoms that worry you. If you've been diagnosed with polycythemia vera, you may be referred to a doctor who specializes in blood conditions (hematologist).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared. Here's some information to help you get ready, and what to expect from your doctor.
What you can do
Your time with your doctor is limited, so preparing a list of questions can help you make the most of your time together. List your questions from most important to least important in case time runs out. For polycythemia vera, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask other questions during your appointment.
What to expect from your doctor
Tests and diagnosis
Bone marrow aspiration or biopsy
If an examination of your bone marrow shows that it's producing higher than normal numbers of blood cells, it may be a sign of polycythemia vera.
Tests for the gene mutation that causes polycythemia vera
Bone marrow biopsy
In a bone marrow aspiration and biopsy, a doctor or nurse uses a thin needle to remove a small amount of liquid bone marrow, usually from a spot in the back of your hipbone called the posterior iliac ...
Treatments and drugs
Polycythemia vera is a chronic condition that can't be cured. Treatment focuses on reducing your amount of blood cells. In many cases, treatment can prevent complications from polycythemia vera and decrease or eliminate the disease's signs and symptoms.
Treatment may include:
Lifestyle and home remedies
You can take steps to help yourself feel better if you've been diagnosed with polycythemia vera. Try to:
Last Updated: 2011-04-02
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