This section provides an overview of the clinical features associated with selected bleeding disorders.
von Willebrand disease (VWD) is the most common inherited bleeding disorder. It ranges in severity and bleeding tendency and is caused by low concentration of or functionally impaired von Willebrand factor.
Alloantibody inhibitors to factor (F) VIII or FIX may develop in a subgroup of patients with haemophilia A (HA) or B (HB) and are a significant complication of haemophilia treatment. These inhibitors partially or completely neutralise the clotting activity of residual factor activity and render standard replacement therapy partially or completely ineffective.
Factor V congenital deficiency (FV CD) is an autosomal recessive bleeding disorder caused by low quantity or reduced function of FV, resulting in an increased bleeding tendency, with symptoms ranging from mild to severe.
Factor X congenital deficiency (FX CD) is an autosomal recessive bleeding disorder caused by low FX activity. Defects in FX affect both the intrinsic and extrinsic clotting cascade and are associated with an increased bleeding tendency.
Factor XI congenital deficiency (FXI CD) is an inherited bleeding disorder with a variable phenotype caused by reduced levels of coagulation FXI activity, resulting in a tendency to bleed in association with surgery or trauma.
Factor XII congenital deficiency (FXII CD) is a rare trait characterised by low or immeasurable FXII activity, which results in prolonged one-stage activated partial thromboplastin times but does not manifest in any clinical bleeding phenotype.
Factor (F) XIII congenital deficiency (FXIII CD) is a rare autosomal recessive bleeding disorder that is the result of an impaired production of FXIII, the terminal enzyme in the blood coagulation cascade that stabilises the already formed blood clot during the haemostatic process.
Glanzmann’s thrombasthenia (GT) is a rare autosomal recessive platelet function disorder caused by a quantitative or qualitative defect in platelet membrane glycoprotein IIb/IIIa, which functions as a receptor for fibrinogen and is involved in platelet aggregation and fibrin clot retraction.
Bernard-Soulier syndrome (BSS) is an inherited bleeding disorder caused by defects in the glycoprotein (GP)Ib-IX-V complex, often resulting in large platelets, low platelet count and abnormal platelet function.