Polycythemia Vera

Polycythemia vera (PV) is a rare blood disorder. It happens when your bone marrow makes too many red blood cells, so your blood is thick and can’t flow like it should. Early on, slow-flowing blood may cause symptoms like blurred or double vision and frequent headaches. Later, you may have itchy skin, nose bleeds and ringing in your ears.

This disease can lead to serious illnesses like blood clots, heart attacks and strokes. Over time, polycythemia vera may turn into myelofibrosis or acute myeloid leukemia. There are treatments that can help ease symptoms and reduce your risk of a serious illness. Other names for polycythemia vera include primary polycythemia, polycythemia rubra vera, erythema and Osler-Vaquez disease.

Is polycythemia vera cancer?

PV is a form of myeloproliferative neoplasm (MPN). MPNs are blood cancers that cause your bone marrow to make too many blood cells.

Symptoms of polycythemia vera

This disease develops very slowly. Most people are in their 60s before they have symptoms. Early symptoms may be common ones, like frequent headaches or feeling more tired than usual. Later, you may have more unusual symptoms, including:

• Blurred vision
• Dizziness
• Excessive bleeding or bruising
• Itchy skin, especially after a warm bath or shower
• Feeling full after eating small amounts of food
• Joint pain
• Redness and burning or tingling sensation in your hands and feet
• Ringing in your ears
• Shortness of breath when you lie down
• Swollen spots on your arms and legs

Polycythemia vera causes

A genetic mutation (change) that happens during your lifetime causes polycythemia vera. The change involves the JAK2 gene. This gene drives red blood stem cell production in your bone marrow. In polycythemia vera, the changed gene in a single red blood stem cell causes it to make many abnormal cells. Eventually, the abnormal cells crowd out normal cells. 

Complications

Polycythemia vera increases your risk of heart issues and more serious blood cancers. Scar tissue in your bone marrow may keep it from making any new blood cells. Healthcare providers may call this PV’s “spent phase” or secondary myelofibrosis. You may develop blood disorders like anemia (low red blood cell levels), thrombocytopenia (low platelet levels) or leukopenia (low white blood cell levels). Other possible complications include:

• Budd Chiari syndrome
• Gout
• Kidney stones
• Peptic ulcers

How doctors diagnose PV

A healthcare provider will do a physical exam. They’ll ask about your symptoms. They may do tests like:

• Complete blood count: This test shows the number of red blood cells in your body, the percentage of red blood cells in your blood and your hemoglobin levels. Hemoglobin is a protein that carries oxygen throughout your body and removes carbon dioxide.
• Erythropoietin blood test: Erythropoietin is a hormone that your kidneys make to boost red blood cell production. Subnormal erythropoietin levels are a sign of polycythemia vera. If the erythropoietin levels are abnormally elevated, it usually points to a secondary polycythemia.
• Bone marrow biopsy: Healthcare providers check bone marrow for high levels of red blood cells and cells that make blood platelets.
• Mutation testing: This test checks for the genetic change that causes PV.

How is polycythemia vera treated?

Treatments focus on managing the disease’s symptoms. Treatments could include:

• Medications: Hydroxyurea (Droxia®) and similar medications manage red blood cell production. Very low doses of selective serotonin reuptake inhibitors (SSRIs) can ease itching. Taking aspirin can reduce the risk of blood clots, strokes and heart attacks. 
• Therapeutic phlebotomy: This is withdrawing blood to reduce the number of red blood cells and ease PV symptoms. The hematocrit level — the percentage of red blood cells in your blood — needs to remain below 45 percent to reduce the risk of complications.
• Interferons: These are injections that can help decrease blood counts and improve symptoms of PV.
• Ruxlotinib or Jakafi: This is a JAK inhibitor that decreases red blood cell production by inhibiting the JAK-STAT pathway that’s activated in PV. This is used when hydroxyurea and/or IFN are not working or not tolerated.
• Stem cell transplant: This may be an option if you have severe PV, or if PV progresses into secondary myelofibrosis or acute myeloid leukemia. 

When should I seek care?

You should contact your healthcare provider if you have symptoms of PV, including:

• Blurred vision
• Frequent headaches
• Itching that gets worse after a warm bath or shower

What’s the life expectancy for someone with polycythemia vera?

A recent study estimated people live about 20 years after a polycythemia vera diagnosis. Life expectancy depends on factors like whether you’re at risk of heart disease or a more serious blood cancer. In general, managing polycythemia vera to reduce red blood cells may help you live longer with the disease. But you’re unique, and so is your experience with this disease. Ask your healthcare provider to explain how this disease may affect how long you may live.

Is there anything I can do to feel better?

There are things you can do to reduce your risk of blood clots and other complications:

• Stay active: Even moderate activity can help keep your blood moving. Regular activity may also help you manage stress that having a chronic disease can cause.
• Stop smoking: Smoking narrows your blood vessels, making it even more difficult for thick red blood cells to move through your blood vessels.
• Avoid high altitudes: PV may lower your oxygen levels. Spending time in high altitudes can lower oxygen levels even more.
• Manage your weight: Eating well and staying active will help you to stay at a weight that’s healthy for you. Managing your weight reduces your heart disease risk.
• Monitor your blood pressure: High blood pressure increases your risk of heart disease. Monitoring your blood pressure helps you manage that risk.