Thrombocytosis is a blood disorder, in which the body produces a surplus of platelets (thrombocytes). Platelets are blood cells that stick together, helping blood clot. The cause of essential thrombocytosis is unknown. Secondary thrombocytosis may have many causes, including acute hemorrhage, anemia, arthritis, classify term="cancer" project="woh" type="bookxref">cancer, and certain medications. Surgery, particularly removal of the spleen (splenectomy), may also be a causative factor.

Two of every three patients who have thrombocytosis do not have any symptoms of the disease at the time of diagnosis. Younger patients may remain symptom-free for years. Enlargement of the spleen is detected in 60% of patients with thrombocytosis. The liver may also be enlarged. As many as half of all patients experience bleeding from the skin, gums, or nose, and 20-50% have some blockage of veins or arteries.

Other symptoms of thrombocytosis include:

• Bloody stools
• Bruising
• Dizziness
• Headache
• Hemorrhage
• Prolonged...