Phenotypes associated with the disease hemophilia B (OMIM:306900):
- Prolonged whole-blood clotting time (HP:0005542): An abnormal prolongation (delay) in the time required by whole blood to produce a visible clot. Evidence: IEA. (OMIM:306900)
- Reduced factor IX activity (HP:0011858): Decreased activity of coagulation factor IX. Factor IX, which itself is activated by factor Xa or factor VIIa to form factor IXa, activates factor X into factor Xa. Evidence: PCS. Frequency: 31/31. (PMID:34017743)
- Hematuria (HP:0000790): The presence of blood in the urine. Hematuria may be gross hematuria (visible to the naked eye) or microscopic hematuria (detected by dipstick or microscopic examination of the urine). Evidence: PCS. Frequency: 2/31. (PMID:34017743)
- Joint hemorrhage (HP:0005261): Hemorrhage occurring within a joint. Evidence: PCS. Frequency: 25/31. (PMID:34017743)
- Prolonged prothrombin time (HP:0008151): Increased time to coagulation in the prothrombin time test, which is a measure of the extrinsic pathway of coagulation. The results of the prothrombin time test are often expressed in terms of the International normalized ratio (INR), which is calculated as a ratio of the patient's prothrombin time (PT) to a control PT standardized for the potency of the thromboplastin reagent developed by the World Health Organization (WHO) using the formula: INR is equal to Patient PT divided by Control PT. Evidence: PCS. Frequency: 0/31. (PMID:34017743)
- X-linked recessive inheritance (HP:0001419): A mode of inheritance that is observed for recessive traits related to a gene encoded on the X chromosome. In the context of medical genetics, X-linked recessive disorders manifest in males (who have one copy of the X chromosome and are thus hemizygotes), but generally not in female heterozygotes who have one mutant and one normal allele. Evidence: TAS. (OMIM:306900)
- Petechiae (HP:0000967): Petechiae are pinpoint-sized reddish/purple spots, resembling a rash, that appear just under the skin or a mucous membrane when capillaries have ruptured and some superficial bleeding into the skin has happened. This term refers to an abnormally increased susceptibility to developing petechiae. Evidence: PCS. Frequency: 2/31. (PMID:34017743)
- 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: PCS. Frequency: 29/31. (PMID:34017743)
- Osteoarthritis (HP:0002758): Degeneration (wear and tear) of articular cartilage, i.e., of the joint surface. Joint degeneration may be accompanied by osteophytes (bone overgrowth), narrowing of the joint space, regions of sclerosis at the joint surface, or joint deformity. Evidence: IEA. (OMIM:306900)
- Persistent bleeding after trauma (HP:0001934). Evidence: PCS. Frequency: 27/31. (PMID:34017743)
- Melena (HP:0002249): The passage of blackish, tarry feces associated with gastrointestinal hemorrhage. Melena occurs if the blood remains in the colon long enough for it to be broken down by colonic bacteria. One degradation product, hematin, imbues the stool with a blackish color. Thus, melena generally occurs with bleeding from the upper gastrointestinal tract (e.g., stomach ulcers or duodenal ulcers), since the blood usually remains in the gut for a longer period of time than with lower gastrointestinal bleeding. Evidence: PCS. Frequency: 4/31. (PMID:34017743)
- Gastrointestinal hemorrhage (HP:0002239): Hemorrhage affecting the gastrointestinal tract. Evidence: IEA. (OMIM:306900)
- Epistaxis (HP:0000421): Epistaxis, or nosebleed, refers to a hemorrhage localized in the nose. Evidence: PCS. Frequency: 7/31. (PMID:34017743)
- 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. (OMIM:306900)
- Hematemesis (HP:0002248): The vomiting of blood. Evidence: PCS. Frequency: 4/31. (PMID:34017743)