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What is thrombophilia?
It is a condition characterized by the increased likelihood of developing blood clots such as in venous thromboembolism.
The origin can be due to anti thrombin deficiency, protein C deficiency or TFPI deficiency.
It’s clinical manifestations include purpura fulminans neonatalis, acute infectious purpura fulminans and idiopathic purpura fulminans.
What is hemostasis?
Hemostasis is the body’s process of stopping bleeding. It involves a series of steps, including vasoconstriction (narrowing of blood vessels), formation of a platelet plug, and blood clotting (coagulation) to seal the wound. Once the injury is healed, the clot dissolves through fibrinolysis. Hemostasis is essential for maintaining the integrity of the circulatory system and preventing excessive blood loss after injury.
What is the difference between primary and secondary hemostasis?
Primary hemostasis involves platelet activation and the formation of a temporary plug, while secondary hemostasis involves the activation of coagulation factors to form a stable blood clot. Both components are essential for effective hemostasis and preventing excessive bleeding.
Symptoms suggestive of a bleeding disorder?
Epistaxis lasting more than 10 min, bruising without trauma, prolonged bleeding after dental work, menorrhagia,.
Other disorders not strictly related but could be involved include thyroid disorders, liver disorders, kidney disorders, bone marrow disorders and use of certai drugs.
Different types of thrombocytopenia?
Idiopathic acute thrombocytopenic purpura of childhood, idiopathic thrombocytopenic purpura of adulthood, it can occur transiently in other situations like autoimmune thrombocytopenia of pregnancy, neonatal immune thrombocytopenia, as a secondary manifestation following autoimmune disorders like SLE, APA syndrome, RA and HIV, could also be drug induced.
What is heparin induced thrombocytopenia?
Heparin-induced thrombocytopenia is aside effect of heparin therapy.This paradoxical effect occurs because heparin binds to platelet factor 4 (PF4), forming a complex that can trigger the immune response.
In HIT, the immune system mistakenly recognizes the heparin-PF4 complex as foreign and produces antibodies against it. These antibodies then bind to the complex, leading to platelet activation and consumption, resulting in thrombocytopenia. Additionally, the activated platelets can promote thrombosis, leading to potentially life-threatening complications such as deep vein thrombosis (DVT) or pulmonary embolism (PE).
Therefore, although heparin is commonly used as an anticoagulant to prevent blood clotting, it can paradoxically induce thrombocytopenia and thrombosis in some individuals through the mechanism of HIT.
What are aPTT and PT?
They are common screening tests used to asses secondary hemostasis.
aPTT evaluates the intrinsic pathway of the coagulation cascade, it uses a reagent to initiation activation of factor XII which activated factor XI, IX and then VIII. The reaction should take around 30 seconds.
PT evaluates the extrinsic pathway, the reagent activates factor VII, then factor X leading to thrombin formation and ultimately fibrin formation. The reaction should last 11/12 seconds.
What are some congenital coagulation disorders?
Hemophilia A and B, von willebrand disease and factor XIII deficiency.
Less severe ones include afibrinogenemia, anti plasmin deficiency.
What is hemophilia A and B?
It is a X linked disorder, the severity depends on the level of factor VIII activity.
Clinically it characterized by hematomas, hemarthrosis, profound anemia, cerebral bleeding.
Treatment include replacing deficient clothing factor for IV infusion of factor VIII concentrates.
Hemophilia B is similar to hemophilia A but it is caused by a deficiency in clotting factor IX.
What is immune thrombocytopenic purpura?
It is an autoimmune disorder characterized by the destruction of platelets by the immune system.
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