A 12-year-old male presented with history of recurrent nose bleeds along with easy bruising with frequent formation of muscle hematomas and prolonged bleeding following tril trauma. On examination, ceain skin lesions were seen along with jaundice, splenomegaly, ahropathy, joint and skin laxity. Lab findings revealed, Normal PT Prolonged aPTT Reduced ristocetin cofactor activity Low factor VIII assay Normal platelet count and size Platelet granules are normal. What is the most probable diagnosis of the above condition: -

This is a case of Von-Willebrand factor disease. The image shows an ecchymotic patch. Von Willebrand disease (vWD) is a common, inherited, genetically and clinically heterogeneous hemorrhagic disorder caused by a deficiency or dysfunction of the protein termed von Willebrand factor (vWF). Consequently, defective vWF interaction between platelets and the vessel wall impairs primary hemostasis. The main treatment options for patients with vWD are desmopressin (DDAVP), recombinant vWF, and vWF/factor VIII (vWF/FVIII) concentrates. Bernard-soulier syndrome is ruled out as platelet size and count are normal. Hemophilia A is ruled out because there is reduced ristocetin cofactor activity.