Furthermore, cases have been reported in cats, horses, cattle, and rabbits. Infusion of platelet concentrates is recommended for correction of hemorrhage associated with platelet-type vWD.VWD can also affect dogs, pigs, and mice. The inheritance pattern of vWD type 3 is autosomal recessive, while the inheritance pattern of hemophilia A is Platelet-type vWD (also known as pseudo-vWD) is an autosomal dominant genetic defect of the platelets.

Large platelet aggregates and high molecular weight vWF multimers are removed from the circulation resulting in thrombocytopenia and diminished or absent large vWF multimers. Consequently, defective vWF interaction between platelets and the vessel wall impairs primary hemostasis. Von Willebrand Disease (VWD) may result from congenital absence of VWF, structural or functional abnormalities or mutations leading to mild decreases in expression of VWF. Type 3 is the most severe form of vWD (homozygous for the defective gene) and is characterized by complete absence of production of vWF. Type 3 VWD is an autosomal recessive disorder, which accounts for only 1% of patients with VWD and is characterized by a virtual absence of VWF and low levels of Factor VIII. There was no known family history of a bleeding disorder. The causal mutation for vWD type 1 was identified in dogs of the breeds In pigs, the causal mutation for vWD type 3 has also been identified.

Persons who had vWD had a normal FVIII gene on the X chromosome, and some had an abnormal vWF gene on chromosome 12. The ristocetin cofactor activity and loss of large vWF multimers are similar to vWD type 2B.
The genetic causes of milder forms of low vWF are still under investigation, and these forms may not always be caused by an abnormal vWF gene. Von Willebrand factor antigen (vWF:Ag) assay is low or normal. For Visual Web Developer, see For the normal function of the coagulation factor, see Christine A. Lee, Rezan A. Kadir, Peter A. Kouides: Inherited Bleeding Disorders in Women P., Oxford Handbook of Clinical Haematology, Chapter 11 Case report von Willebrand Disease Baghaipour, MD Esfehani, MD IRAN. Patients with Low VWF can experience bleeding, despite mild reductions in VWF levels.vWD type 2 is the second most common type of the disorder and has mild to moderate symptoms. Severe haemophilia will have most frequent bleeding occurrences, followed by moderate and then mild haemophilia. "VWD" redirects here. Monoclonally purified factor VIII concentrates and recombinant factor VIII concentrates contain insignificant quantity of vWF, so are not clinically useful.Development of alloantibodies occurs in 10-15% of patients receiving human-derived medium-purity factor VIII concentrates and the risk of allergic reactions including anaphylaxis must be considered when administering these preparations.

The ristocetin cofactor assay is normal. The vWF antigen test is normal, indicating normal quantity of vWF. Estrogen and progesterone compounds available for use in the correction of menorrhagia are Desmopressin is a synthetic analog of the natural antidiuretic hormone For patients with vWD scheduled for surgery and cases of vWD disease complicated by clinically significant hemorrhage, human-derived medium purity factor VIII concentrates, which also contain von Willebrand factors, are available for prophylaxis and treatment. Patients with this subtype are unable to use desmopressin as a treatment for bleeding, because it can lead to unwanted platelet aggregation and aggravation of thrombocytopenia. The vWF antigen levels are normal.

The vWF is qualitatively normal and genetic testing of the von Willebrand gene and vWF protein reveals no mutational alteration. An acquired form can sometimes result from other medical conditions. However, when the assay is performed with the patient's own platelets (platelet-rich plasma), a lower-than-normal amount of ristocetin causes aggregation to occur. Von Willebrand Disease... A Case Study First Admission About The Patient Test Results Second Admission ABO-RH-> A POS PTT-> 36.2 H F-VIII-> 40 L VWF Exon 28->No DNA abnormality detected VWF Ag-> 31** VWF ACTIVITY-> 14** **Blood group specific ranges for VWF Ag and VWF Act:

Numerous variables exist in the testing procedure that may affect the validity of the test results and may result in a missed or erroneous diagnosis.

The clinical picture in pigs is most similar to that in humans with vWD type 3. Von Willebrand disease (vWD) is the most common hereditary blood-clotting disorder in humans.


They mostly come from traumatic injuries. Only small multimer units are detected in the circulation. It arises from a deficiency in the quality or quantity of von Willebrand factor (vWF), a multimeric protein that is required for platelet adhesion.

The patient was on antibiotics for a recent ear infection. Therefore, those pigs are valuable models for clinical and pharmacological research.Mice affected by vWD type 3 were produced by genetic engineering to obtain a small sized model for the human disease. Type 2M vWD is a qualitative defect of vWF characterized by its decreased ability to bind to GPIb receptor on the platelet membrane and normal capability at multimerization. Deposition of The location of oral bleeds was as follows: labial frenum, 60%; tongue, 23%; buccal mucosa, 17% and gingiva and palate, 0.5%. In the case of severe deficiency, there may be spontaneous gingival bleeding, Platelet or coagulation disorders with severely altered hemostasis can cause spontaneous gingival bleeding, as seen in conjunction with hyperplastic hyperemic gingival enlargements in leukemic patients.