blood disorders
Overview of Platelet Disorders
Introduction
Platelets (sometimes called thrombocytes) are cell fragments produced in the bone marrow that circulate in the bloodstream and help How Blood Clots . Thrombopoietin, primarily produced in the liver, stimulates the bone marrow to make large cells (megakaryocytes), which in turn make platelets from material inside their cell body (cytoplasm). Platelets that are not used in clots circulate for 7 to 10 days and are then destroyed. About one third are always stored in the spleen. The platelet count (number of platelets circulating in the bloodstream) is usually about 140,000 to 440,000 platelets per microliter (140 to 440 × 109per liter). The platelet count can vary according to the menstrual cycle. It can decrease near the end of pregnancy (gestational thrombocytopenia) and increase in response to inflammation (secondary, or reactive, thrombocytosis). Neither of these conditions is serious, and most affected people have no problems resulting from either one. Platelet disorders include An abnormal increase in platelets ( Essential Thrombocythemia and A decrease in platelets ( Overview of Thrombocytopenia ) Platelet Dysfunction None Any of these disorders can cause problems with blood clotting. Essential Thrombocythemia , Secondary Thrombocythemia , Overview of Thrombocytopenia , Platelet Dysfunction , 