An abnormal growth and function of blood cells in the bone marrow is characterized by polycythemia vera, a type of myeloproliferative neoplasm. PV occurs when red blood cells are overproduced, causing the blood volume and viscosity to increase, which can result in blood clots, strokes, and cardiovascular problems.
Causes
Although polycythemia vera has no clear cause, it is believed to be caused by mutations in the JAK2 gene, which plays a crucial role in regulating the production of blood cells. PV is characterized by uncontrolled proliferation of blood cells in the bone marrow, particularly red blood cells. Although most cases are sporadic, some may be inherited in rare familial forms.
Symptoms
Polycythemia vera may cause the following symptoms:
-
An increase in blood volume and pressure can cause persistent headaches that feel throbbing or pressure-like.
-
A common symptom of PV is fatigue, because the body must work harder to pump thicker, more viscous blood throughout the body.
-
Reduced blood flow to the brain can cause dizziness, lightheadedness, or fainting.
-
Vision Problems: Impaired blood flow to the eyes can cause blurry vision, double vision, or changes in vision acuity.
-
Due to increased blood cell turnover, some people with PV may experience itching or burning sensations, particularly after exposure to warm water or heat.
Diagnosis
Common diagnostic tests for polycythemia vera include medical history, physical examination, and laboratory tests.
-
A complete blood count (CBC) with differential can detect abnormalities such as elevated red blood cell count, hematocrit, and hemoglobin levels.
-
Testing for JAK2 mutations: Genetic testing can be performed to identify mutations in the JAK2 gene, which are present in the majority of PV patients.
-
In order to confirm the diagnosis of PV, a bone marrow biopsy may be performed to determine the structure and cellularity of the bone marrow.
Treatment
Polycythemia vera can be treated to reduce the risk of complications, such as blood clots and cardiovascular events, as well as alleviate symptoms.
-
To reduce blood volume and viscosity, phlebotomy, or blood removal, is a standard treatment for PV.
-
The overproduction of blood cells can be suppressed with medications such as hydroxyurea, interferon-alpha, or ruxolitinib.
-
Those with PV who are at low to moderate risk of thrombotic events may benefit from low-dose aspirin therapy.
Prevention
Because polycythemia vera is a genetic disorder, it cannot be prevented. In order to prevent complications and improve outcomes, early detection through routine blood tests and monitoring of symptoms can help identify individuals with PV and initiate appropriate treatment.
