Which is not true regarding Bernard syndrome-
Answer is option 1, The ristocetin-induced platelet aggregation is an ex vivo assay for live platelet function. It measures platelet aggregation with the help of von Willebrand factor and exogenous antibiotic ristocetin added in a graded fashion The ristocetin-induced platelet aggregation (RIPA) is an ex vivo assay for live platelet function. It measures platelet aggregation with the help of von Willebrand factor (vWF) and exogenous antibiotic ristocetinadded in a graded fashion. It is similar to the ristocetin cofactor assay but has the added benefit in that it helps in the diagnosis of type 2B/pseudo von Willebrand disease (vWD) and Bernard-Soulier syndrome because it uses patient's live endogenous platelets, whereas ristocetin cofactor assay tests the function of only the vWF and not the platelets. Ristocetin cofactor assay uses the patient's platelet poor plasma (with vWF but no platelets) and adds ristocetin and exogenous formalin-fixed platelets which can passively agglutinate (but not actively aggregate, as they are dead). Formalin does not allow the extrinsic platelets to secrete the vWF of their a-granules, and thus only the activity of the intrinsic vWF is tested. Ref Robbins 9/e pg 82
Ristocetin aggregation is normal
Aggregation with collagen and ADP is normal
Large platelets
Thrombocytopenia
Haematology