What is thrombocytopenia?

Thrombocytopenia is a condition in which the body does not have a normal number of platelets in the blood.

Blood is made up of three major cell types:

  • Red blood cells, which carry oxygen throughout the body.
  • White blood cells, which help fight infection.
  • Platelets, which stick together at the site of a cut or wound to form a clot to stop the bleeding.

People who have thrombocytopenia don’t have enough platelets to form a blood clot, and so they may bleed excessively when they are cut.

What causes thrombocytopenia?

Blood cells (including platelets) are made in the bone marrow, the spongy tissue inside of bones. Certain factors may interfere with the body’s ability to make platelets. Under other circumstances production is normal, but platelets are removed prematurely from the blood. Causes of thrombocytopenia can include:

  • A bone marrow disease or treatment for disease. For instance, diseases such as leukemia (cancer of the bone marrow and bloodstream) and lymphoma (cancer of the lymph system) can cause dysfunction of the bone marrow.
  • Aplastic anemia, a disease that prevents the bone marrow from making blood cells of all types
  • Radiation and chemotherapy treatment for cancer can damage the blood stem cells that eventually become blood cells.
  • Exposure to certain viruses, including Epstein-Barr, cytomegalovirus, hepatitis, and HIV
  • An autoimmune disease (the body’s immune system attacks the body), such as immune thrombocytopenic purpura or ITP)
  • An enlarged spleen (an organ that acts as a filter for the blood and helps the body fight infection). The enlarged spleen traps platelets and prevent them from circulating in the bloodstream.
  • Heredity (the condition is passed down from a parent)
  • Exposure to toxic chemicals
  • Taking certain medications, such as certain antibiotics, cardiovascular drugs, and seizure medications
  • Drinking too much alcohol

What are the symptoms of thrombocytopenia?

The main symptom of thrombocytopenia is bleeding, either on the surface of the skin or inside the body. (In mild cases of thrombocytopenia, there may not be any symptoms.)

Symptoms of thrombocytopenia include the following:

  • Bleeding on various parts of the skin. You may have small red or purple spots called petechiae on your lower legs, or bruising that is purple, red, or brown (known as purpura).
  • Bleeding that doesn’t stop on its own, such as a nosebleed or bleeding from your gums when you brush your teeth
  • Heavier bleeding during menstrual periods
  • Internal bleeding, such as blood in the urine or stool or bleeding from the rectum

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