Rare autosomal recessive platelet dysfunction disorder.
Also called hemorrhagiparous thrombocytic dystrophy.
Rare autosomal recessive coagulopathy that causes a deficiency of glycoprotein Ib (GpIb), the receptor for von Willebrand factor.
Incidence is estimated to be less than 1 in 1 million persons.
Characterized by abnormally large platelets.
Often presents as a bleeding disorder with symptoms of perioperative and postoperative bleeding, bleeding gums, easy bruisability, heavy menstrual bleeding, epistaxis and prolonged bleeding from minor injuries
Characterized by prolonged bleeding time, thrombocytopenia, increased megakaryocytes and decreased platelet survival,
Associated with quantitative or qualitative defects of the platelet glycopotein complex GPIb/V/IX.
Giant platelets may be as frequent as 70–80%.
These platelets do not aggregate to ristocetin, and this defect is not corrected by the addition of normal plasma, distinguishing it from von Willebrand disease.
Platelet responses to physiologic agonists is normal, with the exception of low concentrations of thrombin.
Bleeding can be controlled by platelet transfusion.
Most heterozygote patients do not have a bleeding diathesis.
Inability of platelets to bind and aggregate at sites of vascular endothelial injury.
Three forms of disease:
Type A – GP1BA Type B – GP1BB Type C – GP9