VWF and Bernard-Soulier syndrome: Bernard Soulier Syndrome is an inherited platelet function disorder characterized by mucocutaneous bleeding, thrombocytopenia and giant platelaets with absence of platelet aggregation in response of Ristocetine.1 BSS with an autosomal-recessive inheritance was first described by Bernard and Soulier in 1948.2 The prevalence of BSS has been estimated around one in one million.3 The defect in BSS is due to abnormalities in GPIb-V-IX complex which is required to bind von Willebrand factor in case of vascular injury exposed on subendothelial surfaces.