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What is True about Haemophilia A are all except and explain in detail?
Answer is B (PT is increased): It is PTT which is affected (increased) and not PT (unaffected). Haemophilia A occurs due to deficiency or reduced activity of factor VIII (antihaemophilic factor). Factor VIII is involved in the intrinsic pathway which is measured by PTT and not in extrinsic pathway which is measured as PT.