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Hematology

By ok learning

                        Thrombocytes !
                       
           Clotting Factors !

The clotting factors are a group of chemicals in the blood which is responsible for the formation of blood clot.
Clotting factors are usually inactive but once there is an injury to the wall of the blood vessel, they get activated.
The function of clotting factors is to trigger the formation of a blood clot and stabilize it for as long as necessary.
Clotting factors are therefore known as procoagulants.

Factor I — Fibrinogen; common pathway; converted to fibrin.

Factor II — Prothrombin; common pathway; converted to thrombin that converts fibrinogen to fibrin.

Factor III — Tissue factor (TF) or thromboplastin; extrinsic pathway.

Factor IV — Calcium ions (Ca2+); always present, needed for coagulation.

Factor V — Labile factor, Proaccelerin; common pathway.

Factor VI — not used

Factor VII — Stable factor, Proconvertin; both extrinsic & intrinsic pathway.

Factor VIII — Antihaemophilic factor (AHF); intrinsic pathway: deficiency leads to hemophilia A.

Factor IX — Christmas factor, Plasma thromboplastin component (PTC); intrinsic pathway; deficiency leads to hemophilia B.

Factor X — Stuart-Prower factor; common pathway.

Factor XI — Plasma thromboplastin antecedent (PTA); intrinsic pathway; deficiency leads to hemophilia C.

Factor XII — Hageman factor; intrinsic pathway; activates plasmin.

Factor XIII — Fibrin stabilizing factor (FSF); common pathway; cross-links fibrin.

Factor VIII & IX are sex-linked characters, others are autosomal.
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What are rare clotting factor deficiencies?

Rare clotting factor deficiencies are a group of inherited bleeding disorders caused by a problem with one or several clotting factors.

Clotting factors are proteins in the blood that control bleeding. Many different clotting factors work together in a series of chemical reactions to stop bleeding. This is called the clotting process.

Problems with factor VIII and factor IX are known as hemophilia A and B, respectively. Rare clotting factor deficiencies are bleeding disorders in which one of the other clotting factors (i.e. factors I, II, V, V + VIII, VII, X, XI, or XIII) is missing or not working properly. Less is known about these disorders because they are diagnosed so rarely. In fact, many have only been discovered in the last 40 years.
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