Blood Coagulation Disorders, Inherited
Hemorrhagic and thrombotic disorders that occur as a consequence of inherited abnormalities in blood coagulation.
Blood Coagulation Disorders
Hemorrhagic and thrombotic disorders that occur as a consequence of abnormalities in blood coagulation due to a variety of factors such as COAGULATION PROTEIN DISORDERS; BLOOD PLATELET DISORDERS; BLOOD PROTEIN DISORDERS or nutritional conditions.
The process of the interaction of BLOOD COAGULATION FACTORS that results in an insoluble FIBRIN clot.
Disseminated Intravascular Coagulation
A deficiency or absence of FIBRINOGEN in the blood.
Clotting time of PLASMA recalcified in the presence of excess TISSUE THROMBOPLASTIN. Factors measured are FIBRINOGEN; PROTHROMBIN; FACTOR V; FACTOR VII; and FACTOR X. It is used for monitoring anticoagulant therapy with COUMARINS.
Blood Coagulation Factors
Endogenous substances, usually proteins, that are involved in the blood coagulation process.
The classic hemophilia resulting from a deficiency of factor VIII. It is an inherited disorder of blood coagulation characterized by a permanent tendency to hemorrhage.
Partial Thromboplastin Time
The time required for the appearance of FIBRIN strands following the mixing of PLASMA with phospholipid platelet substitute (e.g., crude cephalins, soybean phosphatides). It is a test of the intrinsic pathway (factors VIII, IX, XI, and XII) and the common pathway (fibrinogen, prothrombin, factors V and X) of BLOOD COAGULATION. It is used as a screening test and to monitor HEPARIN therapy.
Factor X Deficiency
Blood coagulation disorder usually inherited as an autosomal recessive trait, though it can be acquired. It is characterized by defective activity in both the intrinsic and extrinsic pathways, impaired thromboplastin time, and impaired prothrombin consumption.
Factor V Deficiency
A deficiency of blood coagulation factor V (known as proaccelerin or accelerator globulin or labile factor) leading to a rare hemorrhagic tendency known as Owren's disease or parahemophilia. It varies greatly in severity. Factor V deficiency is an autosomal recessive trait. (Dorland, 27th ed)
Heat- and storage-labile plasma glycoprotein which accelerates the conversion of prothrombin to thrombin in blood coagulation. Factor V accomplishes this by forming a complex with factor Xa, phospholipid, and calcium (prothrombinase complex). Deficiency of factor V leads to Owren's disease.
Constituent composed of protein and phospholipid that is widely distributed in many tissues. It serves as a cofactor with factor VIIa to activate factor X in the extrinsic pathway of blood coagulation.
Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.
Activated form of factor X that participates in both the intrinsic and extrinsic pathways of blood coagulation. It catalyzes the conversion of prothrombin to thrombin in conjunction with other cofactors.
Heat- and storage-stable plasma protein that is activated by tissue thromboplastin to form factor VIIa in the extrinsic pathway of blood coagulation. The activated form then catalyzes the activation of factor X to factor Xa.
Storage-stable glycoprotein blood coagulation factor that can be activated to factor Xa by both the intrinsic and extrinsic pathways. A deficiency of factor X, sometimes called Stuart-Prower factor deficiency, may lead to a systemic coagulation disorder.
A plasma protein that is the inactive precursor of thrombin. It is converted to thrombin by a prothrombin activator complex consisting of factor Xa, factor V, phospholipid, and calcium ions. Deficiency of prothrombin leads to hypoprothrombinemia.
Storage-stable blood coagulation factor acting in the intrinsic pathway. Its activated form, IXa, forms a complex with factor VIII and calcium on platelet factor 3 to activate factor X to Xa. Deficiency of factor IX results in HEMOPHILIA B (Christmas Disease).
Use of a thrombelastograph, which provides a continuous graphic record of the physical shape of a clot during fibrin formation and subsequent lysis.
Activated form of factor VII. Factor VIIa activates factor X in the extrinsic pathway of blood coagulation.
An enzyme formed from PROTHROMBIN that converts FIBRINOGEN to FIBRIN.
Blood-coagulation factor VIII. Antihemophilic factor that is part of the factor VIII/von Willebrand factor complex. Factor VIII is produced in the liver and acts in the intrinsic pathway of blood coagulation. It serves as a cofactor in factor X activation and this action is markedly enhanced by small amounts of thrombin.
Activated form of factor XI. In the intrinsic pathway, Factor XI is activated to XIa by factor XIIa in the presence of cofactor HMWK; (HIGH MOLECULAR WEIGHT KININOGEN). Factor XIa then activates factor IX to factor IXa in the presence of calcium.
The natural enzymatic dissolution of FIBRIN.
Blood Coagulation Factor Inhibitors
Substances, usually endogenous, that act as inhibitors of blood coagulation. They may affect one or multiple enzymes throughout the process. As a group, they also inhibit enzymes involved in processes other than blood coagulation, such as those from the complement system, fibrinolytic enzyme system, blood cells, and bacteria.
The process which spontaneously arrests the flow of BLOOD from vessels carrying blood under pressure. It is accomplished by contraction of the vessels, adhesion and aggregation of formed blood elements (eg. ERYTHROCYTE AGGREGATION), and the process of BLOOD COAGULATION.
Activated form of factor IX. This activation can take place via the intrinsic pathway by the action of factor XIa and calcium, or via the extrinsic pathway by the action of factor VIIa, thromboplastin, and calcium. Factor IXa serves to activate factor X to Xa by cleaving the arginyl-leucine peptide bond in factor X.
Hydroxyethyl Starch Derivatives
Clotting time of PLASMA mixed with a THROMBIN solution. It is a measure of the conversion of FIBRINOGEN to FIBRIN, which is prolonged by AFIBRINOGENEMIA, abnormal fibrinogen, or the presence of inhibitory substances, e.g., fibrin-fibrinogen degradation products, or HEPARIN. BATROXOBIN, a thrombin-like enzyme unaffected by the presence of heparin, may be used in place of thrombin.
Activated form of factor XII. In the initial event in the intrinsic pathway of blood coagulation, kallikrein (with cofactor HIGH MOLECULAR WEIGHT KININOGEN) cleaves factor XII to XIIa. Factor XIIa is then further cleaved by kallikrein, plasmin, and trypsin to yield smaller factor XII fragments (Hageman-Factor fragments). These fragments increase the activity of prekallikrein to kallikrein but decrease the procoagulant activity of factor XII.
A protein derived from FIBRINOGEN in the presence of THROMBIN, which forms part of the blood clot.
Stable blood coagulation factor involved in the intrinsic pathway. The activated form XIa activates factor IX to IXa. Deficiency of factor XI is often called hemophilia C.
Stable blood coagulation factor activated by contact with the subendothelial surface of an injured vessel. Along with prekallikrein, it serves as the contact factor that initiates the intrinsic pathway of blood coagulation. Kallikrein activates factor XII to XIIa. Deficiency of factor XII, also called the Hageman trait, leads to increased incidence of thromboembolic disease. Mutations in the gene for factor XII that appear to increase factor XII amidolytic activity are associated with HEREDITARY ANGIOEDEMA TYPE III.
Factor XI Deficiency
A hereditary deficiency of blood coagulation factor XI (also known as plasma thromboplastin antecedent or PTA or antihemophilic factor C) resulting in a systemic blood-clotting defect called hemophilia C or Rosenthal's syndrome, that may resemble classical hemophilia.
A lipid cofactor that is required for normal blood clotting. Several forms of vitamin K have been identified: VITAMIN K 1 (phytomenadione) derived from plants, VITAMIN K 2 (menaquinone) from bacteria, and synthetic naphthoquinone provitamins, VITAMIN K 3 (menadione). Vitamin K 3 provitamins, after being alkylated in vivo, exhibit the antifibrinolytic activity of vitamin K. Green leafy vegetables, liver, cheese, butter, and egg yolk are good sources of vitamin K.
Endogenous factors and drugs that directly inhibit the action of THROMBIN, usually by blocking its enzymatic activity. They are distinguished from INDIRECT THROMBIN INHIBITORS, such as HEPARIN, which act by enhancing the inhibitory effects of antithrombins.
Factor XII Deficiency
An absence or reduced level of blood coagulation factor XII. It normally occurs in the absence of patient or family history of hemorrhagic disorders and is marked by prolonged clotting time.
Fibrin Fibrinogen Degradation Products
Soluble protein fragments formed by the proteolytic action of plasmin on fibrin or fibrinogen. FDP and their complexes profoundly impair the hemostatic process and are a major cause of hemorrhage in intravascular coagulation and fibrinolysis.
Activated form of factor VIII. The B-domain of factor VIII is proteolytically cleaved by thrombin to form factor VIIIa. Factor VIIIa exists as a non-covalent dimer in a metal-linked (probably calcium) complex and functions as a cofactor in the enzymatic activation of factor X by factor IXa. Factor VIIIa is similar in structure and generation to factor Va.
Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.
Activated form of factor V. It is an essential cofactor for the activation of prothrombin catalyzed by factor Xa.