Thrombocytopenia is a medical condition in which the blood platelet count falls below prescribed levels. According to the Mayo Clinic, platelets are blood cells that stop blood loss by sticking together and forming a clot at the site of a ruptured blood vessel. Symptoms of thrombocytopenia include bruising that occurs easily, cuts that bleed for a long time, and unexplained bleeding from the gums or the nose, says the Mayo Clinic. There are three common causes of thrombocytopenia.
Decreased Platelet Formation
The bone marrow produces stem cells that progress to form blood platelets. As the Mayo Clinic points out, medical conditions that affect the bone marrow such as leukemia and anemia can compromise its ability to produce new blood platelets. Other factors that hinder the production of blood platelets by the bone marrow are viral infections, chemotherapy drugs and excessive consumption of alcoholic beverages.
The Body Kills Its Own Platelets
According to the National Heart Lung and Blood Institute (NHLBI), thrombocytopenia can be a problem even if the body is making enough blood platelets. The body's immune system can kill blood platelets for reasons that are not yet known. Certain medicines cause the body to attack and eliminate blood platelets. This happens most often with sulfa drugs and the seizure medications vancomycin, rifampin and phenytoin sodium. Low platelet count can also result from systemic bacterial and viral infections, says the NHLBI. People who undergo certain surgical procedures can experience thrombocytopenia because platelets die as they pass through the instruments and tubing associated with blood transfusions and bypass procedures. Finally, the NHLBI points out that a serious medical condition called disseminated intravascular clotting (DIC) leads to low platelet count because small blood clots form all over the body. DIC occurs as a rare complication of severe infections or trauma, and the numerous blood clots consume a large portion of the available platelets.
The Spleen Retains More Platelets Than It Should
Under normal circumstances, about a third of the platelets in the body are retained by the spleen, says the NHLBI. Liver diseases such as cirrhosis and cancer lead to an enlarged spleen. In this condition, the spleen will retain more platelets than it should so that there are not enough in circulation and thrombocytopenia occurs.
