Congenital Coagulation Abnormalities: Von Willebrand Disease (VWD) PDF

von Willebrand Disease (VWD) Presented by Dr. Sahar Gamal Elbager Assistant Professor of Haematology UMST  von Willebrand Disease (VWD) von Willebrand disease is a congenital bleeding disorder (Both sexes).It is the most common h...

von Willebrand Disease (VWD) Presented by Dr. Sahar Gamal Elbager Assistant Professor of Haematology UMST  von Willebrand Disease (VWD) von Willebrand disease is a congenital bleeding disorder (Both sexes).It is the most common hereditary bleeding disorder. characterized by a lifelong tendency toward easy bruising, frequent epistaxis, and menorrhagia. Von Willebrand factor acts as a carrier for FVIII, Acts as an essential cofactor for platelet adhesion and aggregation. 02/08/25 Dr.Sahar Gamal Elbager 2 02/08/25 Dr.Sahar Gamal Elbager 3  Von Willebrand disease Classification There is either a reduced level or abnormal function of VWF resulting from a point mutation or major deletion. Quantitative – Type 1: Partial vWF deficiency – Type 3: Complete vWF deficiency Qualitative – Type 2: Qualitative mutants of VWF 02/08/25 Dr.Sahar Gamal Elbager 4  Type 1 von Willebrand disease It is accounts for 70-80% of cases Characterized by a partial quantitative decrease of qualitatively normal von Willebrand factor and FVIII An individual with type 1 von Willebrand disease generally has mild clinical symptoms, Inherited as an autosomal dominant trait Labs: proportional reduction in von Willebrand factor activity, von Willebrand factor antigen, and FVIII is observed in type 1 von Willebrand disease. 02/08/25 Dr.Sahar Gamal Elbager 5  Type 3 von Willebrand disease Type 3 is the most severe form of VWD Marked deficiencies of both VWF and FVIIIc in the plasma, Absence of von Willebrand factor from both platelets and endothelial cells, Characterized by severe clinical bleeding 02/08/25 Dr.Sahar Gamal Elbager 6  Type 2 von Willebrand disease Qualitative mutants of VWF Type 2 is divided into four subtypes depending on the type of functional defect. 2A: decreased affinity for GP1b. 2B: increased affinity for platelet resulting in invivo formation of platelet aggregates 2M: large multimer, decreased affinity for platelet 2N: defective factor VIII binding site,decreased affinity for FVIII, but normal in all other aspects (mistaken for hemophilia). 02/08/25 Dr.Sahar Gamal Elbager 7  Secondary classification of type 2VWD 02/08/25 Dr.Sahar Gamal Elbager 8  Lab investigations 1. The bleeding time can be prolonged. 2. Factor VIII levels are often low. If low, a factor VIII VWF binding assay is performed. 3. The APTT may be prolonged. 4. VWF levels are usually low. 5. defective platelet aggregation with ristocetin (VWF: Rco). 6. other agents (ADP), thrombin )is usually normal. 7. Multimer analysis (subtypes) 8. The platelet count is normal except for type 2B disease 02/08/25 Dr.Sahar Gamal Elbager 9  Main clinical and laboratory findings in haemophilia A or B, and vWD 02/08/25 Dr.Sahar Gamal Elbager 10  Main clinical and laboratory findings in haemophilia A or B, and vWD BT PT PTT Platelet Platelet Other tests count function Hemoph A N N P N - FVIII assay Hemoph B N N P N - FIX assay vWD P N P N/ Defect FVIII, vWF aggreg  Thank you 02/08/25 Dr.Sahar Gamal Elbager 12