Thelansis

 Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal stem cell disorder that develops later in life and is characterized by complement-triggered hemolysis, heightened clotting tendencies, and bone marrow dysfunction, potentially stemming from an autoimmune origin. PNH patients have a heightened risk of thrombosis within their abdominal veins, a risk rarely paralleled by other conditions. The increased propensity for blood clot formation can be attributed to several factors: 1.        Altered Fibrinolysis: Abnormal post-translational modification of the GPI-linked uPAR receptor leads to reduced fibrinolysis. 2.        Platelet Activation: There is an upsurge in complement-mediated activation of CD59-negative platelets. 3.        Thrombin Generation: Platelet-derived microparticles contribute to heightened thrombin generation. 4.        Tissue Factor Inhib...

  Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal stem cell disorder characterised by complement-mediated haemolysis, hypercoagulability, and bone marrow failure, probably on an auto-immune basis. Patients with PNH are especially prone to thrombosis in abdominal veins; there are few conditions that confer a high risk. Hypercoagulability may be a consequence of: Decreased fibrinolysis due to abnormal post-translational modification of the GPI-linked uPAR receptor, increased complement-mediated activation of CD59-negative platelets, increased thrombin generation on platelet-derived microparticles, abnormalities of the GPI-linked tissue factor pathway inhibitor, abnormalities of endothelial cells secondary to the presence of a large PNH clone. The clinical symptoms of PNH result from intravascular hemolysis, unusual venous thromboses and bone marrow hypoplasia. The intravascular hemolysis is due to the activation of complement as the abnormal red blood cells lack pro...