Thrombocytopenia is a medical condition characterized by low numbers of blood platelets. Because platelets are responsible for blood clotting after injuries, thrombocytopenia can become serious. There are many causes of the condition; for example, medical afflictions that affect the spleen, bone marrow and immune system. But once these conditions are diagnosed, treatment can be given to improve symptoms and increase the number of platelets in the blood.
Aplastic Anemia
Aplastic anemia is a serious condition that causes the body to stop producing new blood cells, and since platelets are a type of blood cell, aplastic anemia can cause low blood platelets. This condition can be treated with drug therapy, bone marrow transplants or blood transfusions and has a much better prognosis than when it was first discovered.
Viruses
Diseases such as chickenpox and mumps cause temporary reductions in the platelet count, but platelet levels usually return to normal once a virus has run its course. The exception is human immunodeficiency virus (HIV), which cannot be eliminated and may cause repeated episodes of low blood platelets.
Myelodysplasia
Myelodysplasia, also known as myelodysplastic syndrome, is a group of medical disorders that cause the bone marrow to stop functioning normally. When that happens, bone marrow cannot produce blood cells in normal amounts. This disease is more common in adults over the age of 50. However, St. Jude Children's Research Hospital reports that approximately 100 cases of myelodysplastic syndrome are diagnosed in children each year. Bone marrow transplants can improve the survival rate for someone with the disease.
Autoimmune Diseases
Autoimmune diseases can cause low blood platelets because they cause the body's immune system to attack healthy cells. With autoimmune diseases like lupus and chronic fatigue syndrome, the immune system is unable to differentiate between healthy cells and the cells of disease, so it creates antibiodies that attack the healthy cells. Platelets are just one type of cells that may be attacked, which can lead to a reduced blood platelet count.
Thrombotic Thrombocytopenic Purpura
Thrombotic thrombocytopenic purpura is a very rare blood condition that causes blood clots to form in the body's small blood vessels. This condition can lead to low blood platelet levels because platelets are used to form these clots. This leaves a reduced number of platelets to circulate in the blood and can result in internal bleeding, prolonged bleeding from injuries and bleeding into the skin. If these clots block the blood vessels leading to the brain or kidneys, serious medical problems can occur.
Pregnancy
While the cause for thrombocytopenia during pregnancy is unknown, pregnant women who are close to childbirth are known to have reduced blood platelet levels. These levels are the result of decreased platelet production during pregnancy, not the destruction of platelets by the body. Once a baby has been delivered, platelet levels usually return to normal.
Cirrhosis
While platelet destruction and decreased platelet production are well-known causes of low blood platelets, cirrhosis of the liver can also cause this condition too. Cirrhosis of the liver can lead to an enlarged spleen, which normally holds about one-third of the body's platelets as the rest circulate in the blood and form clots when injuries or infection occur. An enlarged spleen holds on to more platelets than necessary, causing reduced numbers of platelets in the blood.
