A patient has normal PT and Platelet Count. The aPTT is increased and factor VIII levels are observed to be 60 lukIL (60%). There is no associated history of bleeding even after a surgical procedure. The most likely diagnosis is:
Answer is C (Lupus Anticoagulant) Isolated prolongation of aPTT with no clinical history of bleeding suggests the presence of Lupus anticoagulant or deficiency of contact factors (Factor XII, Prekallikrein or HMWK)
Factor IX deficiency
Factor VIII inhibitors
Lupus anticoagulant
Thalassemia