In other species: dog , pig

Categories: Haematopoietic system phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 277480 (trait) , 613160 (gene)

Mendelian trait/disorder: yes

Mode of inheritance: Autosomal

Disease-related: yes

Key variant known: no

Cross-species summary: The von Willebrand factor (vWF) is a large multimeric plasma glycoprotein required for platelet adhesion and aggregation. A deficiency or defective vWF results in von Willebrand disease (vWD). vWD are often classified in 3 different types based on the clinical severity and quantity and multimere size of von Willebrand factor. Type I is characterized by low plasma vWF concentrations and mild to moderate bleeding symptoms. Type II disorder is characterised by qualitative abnormalities of the vWF protein and moderate to severe bleeding. Type III is the most severe form of vWD with no detectable or a severe quantitative deficiency of vWF.

Clinical features: vWD is rarely recognized in cats (Thomas 1996). French et al. (1987) diagnosed von Willebrand disease in a 9-year-old male Himalayan cat. The cat presented with persistent oral bleeding after routine dental extraction. Haematuria (blood in the urine), petechia, melena (black stools due to gastrointestinal bleeding) were also observed. Laboratory testing identified disseminated intravascular coagulation (thrombocytopenia, prolonged activated partial thromboplastin time, and increased fibrin degradation products) and recurring iron-deficiency anemia. Coagulation factor assays revealed low factor VIII coagulant activity and undetectable factor VIII-related antigen. The cat initially recovered after treatment but showed spontaneous gingival bleeding 8 month later. No history of abnormal bleeding existed for the cat's sire or dam. [IT thanks DVM student Arianne Tash for suggested changes in April 2022]