Final answer:
TTP is caused by the formation of clots in small vessels, leading to low platelet counts. It can be triggered by damage to the endothelial cells or conditions that increase the likelihood of clotting, and is related to an imbalance in platelet production possibly due to overactivity of thrombopoietin.
Step-by-step explanation:
What Causes Thrombotic Thrombocytopenic Purpura (TTP)?
Thrombotic thrombocytopenic purpura (TTP) is a rare blood disorder that is characterized by the formation of blood clots (thrombi) in small blood vessels throughout the body. These clots can lead to a low platelet count—a condition known as thrombocytopenia—because platelets are used up in forming the clots, and thereby can cause serious health issues, including damage to the body’s organs. Thrombosis has several potential causes such as damage to endothelial cells lining the blood vessels, which can activate clotting mechanisms.
Conditions that may increase the likelihood of thrombosis include venous stasis, often experienced during long airplane flights, autoimmune diseases like lupus, reactions to heparin, and others. Likewise, an imbalance in the production of blood cells related to thrombocytosis—where too many platelets are produced—can increase the risk of abnormal clot formation. Thrombopoietin, a hormone produced by the liver and kidneys, regulates the development of megakaryocytes into platelets; overactivity in this area can lead to an excessive number of platelets and, potentially, to conditions like TTP.