Polycythemia vera (PV) is a rare blood disorder in which your bone marrow produces too many red blood cells. A mutation in the gene JAK2V617F causes about 95 percent of polycythemia vera cases. However, the disorder is not inherited. Researchers don’t yet know why some people develop this mutation in the JAK gene. Although polycythemia cannot be cured, it should be treated in order to avoid potential consequences such as vision problems or even death. Many people who have the right medical care for their PV can go on to lead full and active lives.
While polycythemia vera (also called primary polycythemia), is the most common form of this disorder, it is not the only type. The three major types of polycythemia are:
Polycythemia vera - “True” polycythemia, usually resulting from a mutation of the JAK gene
Secondary polycythemia - A type of disorder that derives from an underlying cause, such as severe heart disease or a lung disorder
Relative polycythemia - A form of the disease caused by severe dehydration due to vomiting, low fluid intake or the use of diuretic medications.
The primary goal of initial treatment is to reduce overall blood volume so that circulation improves. Over the long term, PV needs to be managed in order to maintain normal red blood cell volumes. Common treatments include:
Phlebotomy - In this procedure, a phlebotomist (a technician specially trained in drawing blood) removes blood from a vein in your arm. This procedure reduces the number of red cells in your bloodstream and allows blood to circulate more freely throughout your system. Typically, you will have blood removed weekly. You will undergo this process until the number of red blood cells in your body approaches a normal level.
Medications - For longer-term management, your doctor may recommend certain drugs to inhibit the production of red cells by your bone marrow. The two most common medications for this purpose are hydroxyurea (a common chemotherapy agent) and interferon-alpha (a substance that stimulates your immune system to prevent overactive bone marrow cells from producing so many red cells). If you can’t tolerate hydroxyurea, or if it is ineffective at treating your PV, your doctor may suggest a medication called ruxolitinib. This drug stops defective JAK genes from stimulating the production of an overabundance of red blood cells.
Radiation therapy - Sometimes doctors recommend irradiating the bone marrow in order to suppress red blood cell production. This procedure exposes your body to a dose of radiation in a similar fashion to getting an X-ray taken. The radiation damages some of your bone marrow cells so they cannot make red cells anymore. This should help keep your red cell count in the normal range.
Symptom management - To treat the pain caused by polycythemia vera, you may be told to take aspirin (which will also help thin your blood).
Lifestyle changes - Additionally, you may need to make lifestyle changes in order to relieve itchy skin, a side effect of PV. Small modifications can provide relief. Try taking cool baths instead of hot ones, adding starch or oatmeal to your bath water to soothe the skin or patting yourself dry with a towel instead of rubbing.
Treatment for underlying causes - If you have secondary or relative polycythemia, your doctor will want to treat the underlying cause of the condition. For instance, secondary polycythemia caused by a lung disorder might be treated with supplemental oxygen therapy. Addressing the oxygenation issue might make the polycythemia go away. Since relative polycythemia is caused by dehydration, providing intravenous (IV) fluids might cure it.
Researchers continue to look into new ways to treat polycythemia vera, including methods for blocking the expression of the JAK gene mutation. New treatments on the horizon also include:
Antidepressants for itching - Some clinical trials showed low doses of selective serotonin uptake inhibitors (SSRIs) reduced itching in people with polycythemia.
Leukemia medication - In clinical trials, the leukemia medication imatinib mesylate reduced the size of the spleen and also reduced the need for phlebotomy in some patients with polycythemia vera.
Although polycythemia vera is a chronic, incurable disease, it is important to note that you can expect to live an active lifestyle by following your treatment plan and obtaining ongoing medical care. You should take all medications as recommended and follow up with your doctor regularly to avoid complications.