- Reduced factor VIII activity (HP:0003125): Reduced activity of coagulation factor VIII. Factor VIII (fVIII) is a cofactor in the intrinsic clotting cascade that is activated to fVIIIa in the presence of minute quantities of thrombin. fVIIIa acts as a receptor, for factors IXa and X. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:169802)
- Prolonged partial thromboplastin time (HP:0003645): Increased time to coagulation in the partial thromboplastin time (PTT) test, a measure of the intrinsic and common coagulation pathways. Phospholipid, and activator, and calcium are mixed into an anticoagulated plasma sample, and the time is measured until a thrombus forms. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:169802)
- Epistaxis (HP:0000421): Epistaxis, or nosebleed, refers to a hemorrhage localized in the nose. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Bruising susceptibility (HP:0000978): An ecchymosis (bruise) refers to the skin discoloration caused by the escape of blood into the tissues from ruptured blood vessels. This term refers to an abnormally increased susceptibility to bruising. The corresponding phenotypic abnormality is generally elicited on medical history as a report of frequent ecchymoses or bruising without adequate trauma. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Poor wound healing (HP:0001058): A reduced ability to heal cutaneous wounds. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Joint swelling (HP:0001386). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Persistent bleeding after trauma (HP:0001934). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Prolonged bleeding after surgery (HP:0004846): Bleeding that persists longer than the normal time following a surgical procedure. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Joint hemorrhage (HP:0005261): Hemorrhage occurring within a joint. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Oral cavity bleeding (HP:0030140): Recurrent or excessive bleeding from the mouth. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:169802)
- Menorrhagia (HP:0000132): Prolonged and excessive menses at regular intervals in excess of 80 mL or lasting longer than 7 days. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Limitation of joint mobility (HP:0001376): A reduction in the freedom of movement of one or more joints. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Anemia (HP:0001903): A reduction in erythrocytes volume or hemoglobin concentration. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Intracranial hemorrhage (HP:0002170): Hemorrhage occurring within the skull. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Gastrointestinal hemorrhage (HP:0002239): Hemorrhage affecting the gastrointestinal tract. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Headache (HP:0002315): Cephalgia, or pain sensed in various parts of the head, not confined to the area of distribution of any nerve. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Arthralgia (HP:0002829): Joint pain. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Limb joint contracture (HP:0003121): A contracture (chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin) that prevent normal movement of one or more joints of the limbs. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Progressive joint destruction (HP:0005187). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Reduced von Willebrand factor activity (HP:0008330): Decreased activity of von Willebrand factor. Von Willebrand factor mediates the adhesion of platelets to the collagen exposed on endothelial cell surfaces. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Intramuscular hematoma (HP:0012233): Blood clot formed within muscle tissue following leakage of blood into the tissue. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Cephalohematoma (HP:0012541): Hemorrhage between the skull and periosteum of a newborn resulting from rupture of blood vessels that cross the periosteum. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Macroscopic hematuria (HP:0012587): Hematuria that is visible upon inspection of the urine. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Prolonged bleeding following circumcision (HP:0030137): Bleeding that persists for a longer than usual time following circumcision. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Subdural hemorrhage (HP:0100309): Hemorrhage occurring between the dura mater and the arachnoid mater. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Epidural hemorrhage (HP:0100310): Hemorrhage occurring between the dura mater and the skull. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
- Synovitis (HP:0100769). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:169802)
These phenotypes are associated with the disease Severe hemophilia A (ORPHA:169802).