The condition in which excess of blood platelets called thrombocytes are produced, is called thrombocythemia. Three types of blood cells are available namely red blood cells, white blood cells and platelets. These platelets are called thrombocytes and are responsible for clotting of blood during accident or injury. When the number of platelets is high blood begins to clot easily which can obstruct the blood vessels sometimes causing stroke or myocardial infarction. Essential thrombocythemia is common in old age and is more prevalent in women than men.
Symptoms :
Some people may not have any symptoms during thrombocythemia and they need not have to take any treatment. Some of the symptoms of this disorder is formation of blood clots in hands, feet and extremities of the body. Other common signs are headache, fatigue, chest pain, drowsiness, vision problems, confusion or fainting, tingling sensation in hands and feet, burning pain in the regions of blood clot and enlarged spleen or liver.
Bleeding can occur in nose or mouth and sometimes even on the stool. In severe cases of blood clot it can cause transient ischemic attack causing stroke. In that case, there can be symptoms like numbness on face, arms, legs, double vision or partial loss of vision and difficultly in speech.
Causes :
The major cause for thrombocythemia is over production of thrombocytes. Bone marrow produces all the three types of blood cells which then travel through the blood vessels. Normal range of platelet count is 150,000-450,000 in one microliter of blood. But a person having this disorder will have too much of platelets in the blood which would eventually lead to abnormal bleeding or clotting.
It is believed to be caused by gene mutation. Nearly half the people with this problem will have Janus Kinase 2 gene which is defective.