What Are the Signs and Symptoms of Thrombocythemia and Thrombocytosis?

Most people who have thrombocythemia or thrombocytosis have no signs or symptoms. These conditions often are discovered only after routine blood tests.

People who have primary thrombocythemia are more likely than those who have secondary thrombocytosis to have serious signs and symptoms.

Primary Thrombocythemia

Often, people who have symptoms of primary thrombocythemia only have a mild form of the condition. The most common symptoms are linked to blood clots and bleeding. They are weakness, bleeding, headache, and numbness of the hands and feet.

Blood Clots

In primary thrombocythemia, blood clots most often develop in the brain, hands, and feet. But they can happen anywhere in the body, including in the heart and intestines.

Blood clots in the brain cause symptoms in 25 percent of people who have this condition. Common symptoms are chronic (ongoing) headache and dizziness. In extreme cases, stroke may occur.

Blood clots in the tiny blood vessels of the hands and feet leave them numb and red. This may lead to an intense burning and throbbing pain felt mainly on the palms of the hands and the soles of the feet.

Other signs and symptoms of blood clots may include:

• Changes in speech or awareness, ranging from confusion to passing out
• Seizures
• Upper body discomfort in one or both arms, the back, neck, jaw, or stomach
• Shortness of breath and nausea (feeling sick to your stomach)

Blood clots in the placenta cause fetal death or miscarriage in half of pregnant women who have primary thrombocythemia.

Blood clots aren't only linked to having thrombocythemia or thrombocytosis, but to other factors as well. Age (being older than 60), prior blood clots, diabetes, high blood pressure, and smoking also increase your risk for blood clots.

Bleeding

Bleeding most often occurs in people who have platelet counts higher than 1 million platelets per microliter of blood. Signs of bleeding include nosebleeds, bruising, bleeding from the mouth or gums, or blood in the stools.

Although bleeding usually is linked to having a low platelet count, it also can occur in people who have high platelet counts. Blood clots that develop in thrombocythemia or thrombocytosis may use up your body's platelets. This means that not enough platelets are left in your bloodstream to seal off any cuts and breaks in the blood vessels.

Another cause of bleeding in patients who have very high platelets counts is a condition called von Willebrand Disease. This condition affects the blood clotting process.

In rare cases of primary thrombocythemia (less than 2 percent), the faulty bone marrow cells will cause a form of leukemia (lu-KE-me-ah). Leukemia is a cancer of the blood cells.

Secondary Thrombocytosis

People who have secondary thrombocytosis have a lower risk for bleeding and blood clots. This is because their platelets are generally normal (unlike in primary thrombocythemia) and their platelet counts aren't as high.

However, people who have this condition are at higher risk for blood clots and bleeding if they're on bed rest or have a severe disease of the arteries.