Mega platelets are seen in?

Ans. is 'd' i.e., Bernard souiier syndrome Bernard soulier syndromeo It is an autosomal recessive disorder due to deficiency or dysfunction of glycoprotein Ib-IX (Gp Ib/IX). Thus there is defect in platelet adhesion.o Platelet aggregation is normal in response to standard agonists like collagen, ADP or thrombin. But platelets fail to aggregate in response to ristocetin (as ristacetin facilitates binding of vWF and Gp lb- IX).o There may be thrombocytopenia with abnormally large platelets.o There is prolonged BT. vWF is normal.About other optionso Small sized platelets are characteristic of Wiskot-Aldrich syndrome (WAS)o Platelet morphology is normal in Glanzmann thrombasthenia & Von willebrand disease.