Essential Thrombocythemia (ET)

Essential Thrombocythemia causes the body to produce too many blood platelets-thrombocytes.

It can cause abnormal blotting or bleeding. The bone marrow makes too many platelet-forming cells or megakaryocytes, which release platelets into your blood. Approximately 50 percent of patients with ET have the JAK2 gene mutation. Other gene mutations are linked to ET and other myeloproliferative neoplasms.

Some people with essential thrombocythemia have no symptoms. Others may experience the following:

• Formation of clots

• Headache

• Dizziness

• Chest Pain

• Weakness

• Fainting

• Temporary vision changes

• Numbness or tingling in hands and feet

• Throbbing or burning pain in hands (erythromelalgia)

• Enlarged spleen

ET may cause bleeding especially if platelet counts are extremely high or more than 1 million platelets per microliter of blood.

Bleeding may take the form of:

• Nosebleeds

• Bruising

• Bleeding in the mouth or gums

• Bloody stool

Current Treatments

  • Hydroxyurea: Works by suppressing bone marrow production including platelets.
  • Anagrelide: Works by inhibiting the maturation of platelets from megakaryocytes.
  • Interferon alfa-2B (Intron A): Works by preventing abnormal or malignant cells from increasing in numbers.
  • Ropefinterferon alfa-2b: A monopegylated interferon in clinical trials for ET.
  • Low dose aspirin: May be helpful in treating patients with symptoms of microvascular occlusion.