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Secondary Thrombocythemia

(Reactive Thrombocytosis )


Jane Liesveld

, MD, James P. Wilmot Cancer Institute, University of Rochester Medical Center

Last full review/revision Sep 2020| Content last modified Sep 2020
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Secondary thrombocythemia is excess platelets in the bloodstream that develops as a result of another disorder and rarely leads to excessive blood clotting or bleeding.

Platelets Platelets The main components of blood include Plasma Red blood cells White blood cells Platelets read more Platelets (thrombocytes) are cell-like particles in the blood that help the body form blood clots. Platelets are normally produced in the bone marrow by cells called megakaryocytes. In thrombocythemia, the body produces too many platelets. Thrombocythemia can be

Causes of secondary thrombocythemia include

People with secondary thrombocythemia usually have no symptoms related to the high number of platelets (unlike people with primary thrombocythemia. Symptoms of the underlying condition usually dominate.

Although an increased number of platelets might be thought to cause excessive blood clotting, this rarely happens in secondary thrombocythemia unless people also have severe arterial disease or prolonged immobility. Although some people with essential thrombocythemia have an increased risk of bleeding, this is not a concern with secondary thrombocythemia.

Secondary thrombocythemia is diagnosed—and distinguished from primary thrombocythemia Essential Thrombocythemia Essential thrombocythemia is a myeloproliferative neoplasm in which excess platelets are produced, leading to abnormal blood clotting or bleeding. The hands and feet may burn, turn red, and... read more —when people with high platelet counts have a condition that readily accounts for the high number of platelets.

To identify possible causes, doctors do blood tests, sometimes including genetic testing, and occasionally a bone marrow biopsy Bone Marrow Examination Red blood cells, most white blood cells, and platelets are produced in the bone marrow, the soft fatty tissue inside bone cavities. Sometimes a sample of bone marrow must be examined to determine... read more . Other tests such as radiologic tests may be needed to ascertain the cause of the platelet elevation.

Treatment is aimed at the cause of the platelet elevation. If the treatment is successful, the platelet count will return to normal.

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Acute myeloid leukemia (AML) is a life-threatening disorder in which certain blood cells become cancerous and rapidly replace normal cells in the bone marrow. As normal blood cells are replaced by cancerous cells, people with AML become anemic from too few red blood cells. They develop infections easily because there are too few white blood cells to fight infections, and their blood does not clot well because of too few platelets. Which of the following additional symptoms of AML may be caused by having too few white blood cells?
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