Essential thrombocythemia

Free

E-Newsletters

Subscribe to receive the latest updates on health topics. About our newsletters

  • Housecall
  • Alzheimer's caregiving
  • Living with cancer

Tests and diagnosis

By Mayo Clinic staff

Blood tests that can help confirm a diagnosis of essential thrombocythemia include:

  • Complete blood count (CBC). This test determines the number of platelets in your blood.
  • Blood smear. A small amount of your blood is examined under a microscope to view the condition of your platelets, such as whether they're abnormally large or clumped together.
  • Genetic testing. Special tests can determine whether you have chromosomal abnormalities that can cause a high platelet count and whether you have a JAK2 gene mutation.
  • Other blood tests. Your doctor may check the level of iron in your blood or test for markers of inflammation.

If your blood count is above 450,000 platelets per microliter of blood, your doctor will look for an underlying condition. If there's no evident cause of your high platelet count, and it remains high over time, your doctor may suggest a bone marrow test. The two types of bone marrow tests provide different but complementary information about your blood cells. Often they're done together.

  • Bone marrow aspiration. Your doctor extracts a small amount of your liquid bone marrow through a needle and examines it under a microscope, looking for abnormal cells.
  • Bone marrow biopsy. Your doctor takes a sample of solid bone marrow tissue through a needle for examination under a microscope. If you have ET, your bone marrow has a higher than normal number of the large cells that make platelets (megakaryocytes).
References
  1. Thrombocythemia. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/print/sec14/ch178/ch178d.html. Accessed June 12, 2010.
  2. Tefferi A. Diagnosis and clinical manifestations of essential thrombocythemia. http://www.uptodate.com/home/index.html. Accessed June 12, 2010.
  3. What are thrombocythemia and thrombocytosis? National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/dci/Diseases/thrm/thrm_all.html. Accessed June 12, 2010.
  4. Tefferi A. Myeloproliferative disorders: Essential thrombocythemia and primary myeolfibrosis. In: Goldman L, et al, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2008. http://www.mdconsult.com/das/book/body/206064361-4/1014199238/1492/658.html#4-u1.0-B978-1-4160-2805-5..50182-8--cesec8_7943. Accessed June 12, 2010.
  5. Essential or primary thrombocythemia. The Leukemia & Lymphoma Society. http://www.leukemia-lymphoma.org/attachments/National/br_1178803674.pdf. Accessed June 12, 2010.
  6. Chronic myeloproliferative disorders treatment (PDQ): Patient version. National Cancer Institute. http://www.cancer.gov/cancertopics/pdq/treatment/myeloproliferative/patient/allpages/print. Accessed June 12, 2010.
  7. Vannucchi A, et al. Advances in understanding and management of myeoloproliferative neoplasms. CA: A Cancer Journal for Clinicians. 2009;59:171.
  8. Finazzi G, et al. Essential thrombocythemia. In: Hoffman R, et al. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Churchill Livingstone Elsevier; 2009. http://www.mdconsult.com/book/player/book.do?method=display&type=bookPage&decorator=header&eid=4-u1.0-B978-0-443-06715-0..50073-X&uniq=206064361&isbn=978-0-443-06715-0&sid=1014199238. Accessed June 17, 2010.
  9. Tefferi A. Prognosis and treatment of essential thrombocythemia. http://www.uptodate.com/home/index.html. Accessed June 12, 2010.
  10. Myeloproliferative disorders. Lab Tests Online. http://www.labtestsonline.org/understanding/conditions/myelopro_disorders-3.html#. Accessed June 17, 2010.
DS01087 July 16, 2010

© 1998-2012 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "EmbodyHealth," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research.

Print Share Reprints

Advertisement


Text Size: smaller largerlarger