thrombocytopenia throm·bo·cy·to·pe·ni·a (thrŏm'bō-sī'tə-pē'nē-ə)
An abnormal decrease in the number of platelets in the blood. Also called thrombopenia.
abnormally low number of platelets (thrombocytes) in the circulation. Thrombocytopenia may occur as a result of decreased platelet production, when the bone marrow is malfunctioning or not functioning (e.g., in leukemia, from an excess of certain drugs or radiation, in certain anemias, or from a congenital lack of megakaryocytes, cells in the bone marrow that give rise to platelets), or as a result of increased platelet destruction (e.g., from a malfunctioning spleen, congestive heart failure, blood transfusion after hemorrhage, or incompatible blood transfusion). Symptoms of thrombocytopenia include small hemorrhages into the skin, nosebleeds, and easy bruising; sometimes gastrointestinal bleeding, excess menstrual bleeding, or other hemorrhage is observed. Treatment includes rest, protection from injury, and sometimes platelet transfusion.
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