hemophilia A

hemophilia /he·mo·phil·ia/ (he″mo-fil´e-ah) a hereditary hemorrhagic diathesis due to deficiency of a blood coagulation factor.

---

hemophilia A  classical h.; an X-linked recessive form due to deficiency of coagulation factor VIII.

hemophilia B  Christmas disease; an X-linked recessive form due to deficiency of coagulation factor IX.

hemophilia C  an autosomal disorder due to lack of coagulation factor XI; seen predominantly in persons of Jewish ancestry and characterized by minor bleeding, mild bruising, severe prolonged postsurgical bleeding, and abnormal clotting test times.

classical hemophilia  h. A.

vascular hemophilia  von Willebrand's disease.

---

hemophilia A

n.

Hemophilia due to deficiency of factor VIII, characterized by prolonged clotting time, decreased formation of thromboplastin, and diminished conversion of prothrombin.

---

hemophilia A,

a hereditary blood disorder usually expressed in males that is transmitted as an X-linked recessive trait and caused by a deficiency of coagulation factor VIII. Hemophilia A is considered the classic type of hemophilia. See also coagulation factor, hemophilia.

---

hemophilia (bleeder's disease) (hē´mōfil´ē),

n a sex-linked genetic disease manifested in males and characterized by severe hemorrhage.

hemophilia A (classic hemophilia),

n a hemorrhagic diathesis resulting from a deficiency of antihemophilic globulin (AHG); inherited as a recessive sex-linked characteristic and characterized by recurrent bouts of bleeding from even trivial injury. The coagulation time is prolonged, but the bleeding time is normal.

hemophilia B (Christmas disease, hemophilia II, hemophilioid state C),

n a hemorrhagic diathesis resulting from a deficiency of plasma thromboplastin component (PTC); transmitted as a sex-linked recessive characteristic and characterized clinically by the same manifestations as classic hemophilia. There is a delay in the generation of thromboplastin. The platelet count, bleeding time, tourniquet test, and thrombin and prothrombin times are normal.

hemophilia C (plasma thromboplastin antecedent [PTA] deficiency, Rosenthal's syndrome),

n a hemophilia-like condition believed to result from a deficiency of plasma thromboplastin antecedent (PTA), transmitted as a simple autosomal dominant trait and characterized by a moderate bleeding tendency after extraction of teeth or after tonsillectomy. Prothrombin consumption and thromboplastin generation are abnormal. See also factor XI.

hemophilia, classic,

n See hemophilia A.

hemophilia, vascular,

n a hereditary hemorrhagic disorder affecting both sexes and associated with a deficiency of antihemophilic globulin and vascular abnormalities characteristic of pseudohemophilia (von Willebrand disease). The bleeding time is prolonged, and severity of bleeding varies considerably among persons with this condition.

---

hemophilia

a condition characterized by impaired coagulability of the blood, and a strong tendency to bleed. See also deficiency of the following clotting factors, afibrinogenemia and hypoprothrombinemia, and proconvertin, stuart factor, plasma thromboplastin antecedent, hageman factor and fibrin stabilizing factor.

---

hemophilia A

classical hemophilia, due to deficiency of clotting factor VIII-C; occurs in dogs, horses and cats and is transmitted by the female to the male as a sex-linked recessive abnormality.

hemophilia B

a form similar to classical hemophilia but due to a deficiency of clotting factor IX; called also christmas disease and factor IX deficiency. Occurs in dogs and cats.

hemophilia C

in dogs an autosomal dominant form due to deficiency of clotting factor XI (plasma thromboplastin antecedent). Called also factor XI deficiency. The disease also occurs in cattle but the clinical disease is minor and it is inherited as a recessive character.

double hemophilia

dogs with both hemophilia A and hemophilia B have been produced experimentally.

vascular hemophilia

deficiency of clotting factor VIII and factor VIII-related antigen occurs in many breeds of dogs, particularly Doberman Pinschers, and in rabbits and pigs. See also von willebrand's disease.

---

hemophilia A

Classical hemophilia, factor VIII deficiency hemophilia Hematology An X-R coagulopathy due to a marked ↓ of factor VIII Physiology Factor VIII circulates as a noncovalent complex with von Willebrand factor, which once cleaved by thrombin or by factor Xa enables factor VIII to bind to phospholipid surfaces of damaged cells and adherent activated platelets Clinical Hemophilia A is heterogenous as moderate–1—4% normal; or mild–5—25% normal factor VIII deficiency occurs; classic findings–joint hemorrhage of knee > elbow >etc, muscle hemorrhage, bruising, prolonged and potentially fatal post-traumatic or post-op hemorrhage Lab Normal platelets, normal prothrombin time, ↑ aPTT, ↓ factor VIII Treatment Recombinant factor VIII. See AIDSgate, Factor VIII.