Format

Send to:

Choose Destination

Links from Books

Items: 3

1.

Von Willebrand disease, recessive form

von Willebrand disease (VWD), a congenital bleeding disorder caused by deficient or defective plasma von Willebrand factor (VWF), may only become apparent on hemostatic challenge, and bleeding history may become more apparent with increasing age. Type 1 VWD (~70% of VWD) typically manifests as mild mucocutaneous bleeding. Type 2 VWD accounts for approximately 25% of VWD; the subtypes are: Type 2A, which usually manifests as mild to moderate mucocutaneous bleeding; Type 2B, which typically manifests as mild to moderate mucocutaneous bleeding that can include thrombocytopenia that worsens in certain circumstances; Type 2M, which typically manifests as mild-moderate mucocutaneous bleeding; Type 2N, which can manifest as excessive bleeding with surgery and mimics mild hemophilia A. Type 3 VWD (<5% of VWD) manifests with severe mucocutaneous and musculoskeletal bleeding. Diagnosis/testing The diagnosis of VWD typically requires assays of hemostasis factors specific for VWD and/or molecular genetic testing of VWF, the only gene in which pathogenic variants are known to cause VWD. In most cases the diagnosis requires a positive family history. ManagementTreatment of manifestations: Affected individuals benefit from care in a comprehensive bleeding disorders program. Severe bleeding episodes can be prevented or controlled with intravenous infusion of virally inactivated plasma-derived clotting factor concentrates containing both VWF and FVIII; depending on the VWD type, mild bleeding episodes usually respond to intravenous or subcutaneous treatment with desmopressin, a vasopressin analog. Other treatments that can reduce symptoms include fibrinolytic inhibitors and hormones for menorrhagia. Pregnant women with VWD are at increased risk for bleeding complications at or following childbirth. Prevention of primary manifestations: Prophylactic infusions of VWF/FVIII concentrates in individuals with type 3 VWD. Prevention of secondary complications: Cautious use of desmopressin (particularly in those age <2 years because of the potential difficulty in restricting fluids in this age group). Vaccination for hepatitis A and B. Surveillance: Follow up in centers experienced in the management of bleeding disorders. For those with type 3 VWD: periodic evaluations by a physiotherapist to monitor joint mobility. Agents/circumstances to avoid: Activities involving a high risk of trauma, particularly head injury; medications with effects on platelet function (ASA, clopidogrel, or NSAIDS); circumcision in infant males should only be considered following consultation with a hematologist. Evaluation of relatives at risk: If the familial pathogenic variant(s) are known, molecular genetic testing for at-risk relatives to allow early diagnosis and treatment, if needed. Pregnancy management: As VWF levels increase throughout pregnancy, women with baseline VWF and FVIII levels of >30 IU/dL are likely to achieve normal levels by the time of delivery, whereas those with a basal level <20 IU/dL and those with baseline VWF:RCo/VWF:Ag ratio <0.6, are likely to require replacement therapy; desmopressin has been used successfully to cover delivery in women with type 1 VWD; delayed, secondary postpartum bleeding may be a problem. Therapies under investigation: Recombinant VWF, now in clinical trials, is expected to be available soon for use instead of plasma-derived VWF. [from GeneReviews]

MedGen UID:
338488
Concept ID:
C1848525
Disease or Syndrome
2.

von Willebrand disease type 2

von Willebrand disease (VWD), a congenital bleeding disorder caused by deficient or defective plasma von Willebrand factor (VWF), may only become apparent on hemostatic challenge, and bleeding history may become more apparent with increasing age. Type 1 VWD (~70% of VWD) typically manifests as mild mucocutaneous bleeding. Type 2 VWD accounts for approximately 25% of VWD; the subtypes are: Type 2A, which usually manifests as mild to moderate mucocutaneous bleeding; Type 2B, which typically manifests as mild to moderate mucocutaneous bleeding that can include thrombocytopenia that worsens in certain circumstances; Type 2M, which typically manifests as mild-moderate mucocutaneous bleeding; Type 2N, which can manifest as excessive bleeding with surgery and mimics mild hemophilia A. Type 3 VWD (<5% of VWD) manifests with severe mucocutaneous and musculoskeletal bleeding. Diagnosis/testing The diagnosis of VWD typically requires assays of hemostasis factors specific for VWD and/or molecular genetic testing of VWF, the only gene in which pathogenic variants are known to cause VWD. In most cases the diagnosis requires a positive family history. ManagementTreatment of manifestations: Affected individuals benefit from care in a comprehensive bleeding disorders program. Severe bleeding episodes can be prevented or controlled with intravenous infusion of virally inactivated plasma-derived clotting factor concentrates containing both VWF and FVIII; depending on the VWD type, mild bleeding episodes usually respond to intravenous or subcutaneous treatment with desmopressin, a vasopressin analog. Other treatments that can reduce symptoms include fibrinolytic inhibitors and hormones for menorrhagia. Pregnant women with VWD are at increased risk for bleeding complications at or following childbirth. Prevention of primary manifestations: Prophylactic infusions of VWF/FVIII concentrates in individuals with type 3 VWD. Prevention of secondary complications: Cautious use of desmopressin (particularly in those age <2 years because of the potential difficulty in restricting fluids in this age group). Vaccination for hepatitis A and B. Surveillance: Follow up in centers experienced in the management of bleeding disorders. For those with type 3 VWD: periodic evaluations by a physiotherapist to monitor joint mobility. Agents/circumstances to avoid: Activities involving a high risk of trauma, particularly head injury; medications with effects on platelet function (ASA, clopidogrel, or NSAIDS); circumcision in infant males should only be considered following consultation with a hematologist. Evaluation of relatives at risk: If the familial pathogenic variant(s) are known, molecular genetic testing for at-risk relatives to allow early diagnosis and treatment, if needed. Pregnancy management: As VWF levels increase throughout pregnancy, women with baseline VWF and FVIII levels of >30 IU/dL are likely to achieve normal levels by the time of delivery, whereas those with a basal level <20 IU/dL and those with baseline VWF:RCo/VWF:Ag ratio <0.6, are likely to require replacement therapy; desmopressin has been used successfully to cover delivery in women with type 1 VWD; delayed, secondary postpartum bleeding may be a problem. Therapies under investigation: Recombinant VWF, now in clinical trials, is expected to be available soon for use instead of plasma-derived VWF. [from GeneReviews]

MedGen UID:
224736
Concept ID:
C1264040
Disease or Syndrome
3.

von Willebrand disease type 1

von Willebrand disease (VWD), a congenital bleeding disorder caused by deficient or defective plasma von Willebrand factor (VWF), may only become apparent on hemostatic challenge, and bleeding history may become more apparent with increasing age. Type 1 VWD (~70% of VWD) typically manifests as mild mucocutaneous bleeding. Type 2 VWD accounts for approximately 25% of VWD; the subtypes are: Type 2A, which usually manifests as mild to moderate mucocutaneous bleeding; Type 2B, which typically manifests as mild to moderate mucocutaneous bleeding that can include thrombocytopenia that worsens in certain circumstances; Type 2M, which typically manifests as mild-moderate mucocutaneous bleeding; Type 2N, which can manifest as excessive bleeding with surgery and mimics mild hemophilia A. Type 3 VWD (<5% of VWD) manifests with severe mucocutaneous and musculoskeletal bleeding. Diagnosis/testing The diagnosis of VWD typically requires assays of hemostasis factors specific for VWD and/or molecular genetic testing of VWF, the only gene in which pathogenic variants are known to cause VWD. In most cases the diagnosis requires a positive family history. ManagementTreatment of manifestations: Affected individuals benefit from care in a comprehensive bleeding disorders program. Severe bleeding episodes can be prevented or controlled with intravenous infusion of virally inactivated plasma-derived clotting factor concentrates containing both VWF and FVIII; depending on the VWD type, mild bleeding episodes usually respond to intravenous or subcutaneous treatment with desmopressin, a vasopressin analog. Other treatments that can reduce symptoms include fibrinolytic inhibitors and hormones for menorrhagia. Pregnant women with VWD are at increased risk for bleeding complications at or following childbirth. Prevention of primary manifestations: Prophylactic infusions of VWF/FVIII concentrates in individuals with type 3 VWD. Prevention of secondary complications: Cautious use of desmopressin (particularly in those age <2 years because of the potential difficulty in restricting fluids in this age group). Vaccination for hepatitis A and B. Surveillance: Follow up in centers experienced in the management of bleeding disorders. For those with type 3 VWD: periodic evaluations by a physiotherapist to monitor joint mobility. Agents/circumstances to avoid: Activities involving a high risk of trauma, particularly head injury; medications with effects on platelet function (ASA, clopidogrel, or NSAIDS); circumcision in infant males should only be considered following consultation with a hematologist. Evaluation of relatives at risk: If the familial pathogenic variant(s) are known, molecular genetic testing for at-risk relatives to allow early diagnosis and treatment, if needed. Pregnancy management: As VWF levels increase throughout pregnancy, women with baseline VWF and FVIII levels of >30 IU/dL are likely to achieve normal levels by the time of delivery, whereas those with a basal level <20 IU/dL and those with baseline VWF:RCo/VWF:Ag ratio <0.6, are likely to require replacement therapy; desmopressin has been used successfully to cover delivery in women with type 1 VWD; delayed, secondary postpartum bleeding may be a problem. Therapies under investigation: Recombinant VWF, now in clinical trials, is expected to be available soon for use instead of plasma-derived VWF. [from GeneReviews]

MedGen UID:
220393
Concept ID:
C1264039
Disease or Syndrome
Format

Send to:

Choose Destination

Supplemental Content

Find related data

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Support Center