The hemophilias are a group of inherited, or sometimes acquired, disorders of secondary hemostasis Secondary hemostasis The coagulation cascade is a series of reactions that ultimately generates a strong, cross-linked fibrin clot. Hemostasis due to deficiency of specific clotting factors. Hemophilia A is a deficiency of factor VIII Factor VIII Factor VIII of blood coagulation. 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. Hemostasis, hemophilia B a deficiency of factor IX Factor IX Storage-stable blood coagulation factor acting in the intrinsic pathway of blood coagulation. Its activated form, ixa, forms a complex with factor VIII and calcium on platelet factor 3 to activate factor X to Xa. Hemostasis, and hemophilia C a deficiency of factor XI. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with bleeding events that may be spontaneous or associated with minor or major trauma. Management is focused mainly on treatment of acute bleeding events and prevention of bleeding events via replacement of deficient factors.
Last updated: 18 Mar, 2021
Hemophilias are a group of disorders of secondary hemostasis Secondary hemostasis The coagulation cascade is a series of reactions that ultimately generates a strong, cross-linked fibrin clot. Hemostasis due to the deficiency of specific clotting factors.
About 400 children per year are born with hemophilia in the United States.
3 different types have been described:
Genetic mutation Mutation Genetic mutations are errors in DNA that can cause protein misfolding and dysfunction. There are various types of mutations, including chromosomal, point, frameshift, and expansion mutations. Types of Mutations resulting in deficiency of clotting factors:
Acquired hemophilia:
Location of F8 gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics for coagulation factor VIII Factor VIII Factor VIII of blood coagulation. 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. Hemostasis: Xq28, resulting in hemophilia A
Image: “F8 gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics location” by Genome Genome The complete genetic complement contained in the DNA of a set of chromosomes in a human. The length of the human genome is about 3 billion base pairs. Basic Terms of Genetics Decoration Page/NCBI. License: Public DomainPresentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor is based mainly on the severity of the factor deficiency.
Mild to moderate deficiency:
More severe deficiency:
Extensive subcutaneous hematoma Hematoma A collection of blood outside the blood vessels. Hematoma can be localized in an organ, space, or tissue. Intussusception/ ecchymosis Ecchymosis Extravasation of blood into the skin, resulting in a nonelevated, rounded or irregular, blue or purplish patch, larger than a petechia. Orbital Fractures of the limbs, thorax, and abdomen in a patient with hemophilia
Image: “Extensive subcutaneous ecchymoses” by Arthur Bloom Hemophilia Centre, School of Medicine, Cardiff University, University Hospital of Wales, Cardiff, CF14 4XN, UK. License: CC BY 2.0Hemarthrosis in a 6-year-old boy
Image: “ Hémarthrose” by Service de Pédiatrie, Hôpital Al AL Amyloidosis Farabi, CHU Mohamed VI, Université Mohamed I, Oujda, Maroc. License: CC BY 2.0The diagnosis of hemophilia is made on the basis of clinical suspicion (usually due to a bleeding event) followed by demonstration of deficient factor levels (< 40%).