Hemophilia B is clinically indistinguishable from Hemophilia A in terms of presentation.

Hemophilia B is clinically indistinguishable from Hemophilia A in terms of presentation.

• A. Clinically indistinguishable from Hemophilia A
• B. Factor IX is deficiency
• C. Presents with normal PTT
• D. Occurs in females predominantly

Answer: (A)

Both Hemophilia A and Hemophilia B produce similar bleeding patterns because each is a deficiency in a component of the intrinsic coagulation pathway and they are inherited in an X-linked manner. In practice, affected individuals—mostly males—present with similar symptoms: easy bruising, mucosal bleeding, and deep tissue or joint bleeds. That is why their clinical presentation is indistinguishable. To tell them apart, you need specific factor assays: Hemophilia A is due to factor VIII deficiency, while Hemophilia B is due to factor IX deficiency. Lab tests also show a prolonged aPTT with a normal PT in both conditions, not a normal aPTT. Remember that both are X-linked, so females are usually carriers rather than predominantly affected.

Both Hemophilia A and Hemophilia B produce similar bleeding patterns because each is a deficiency in a component of the intrinsic coagulation pathway and they are inherited in an X-linked manner. In practice, affected individuals—mostly males—present with similar symptoms: easy bruising, mucosal bleeding, and deep tissue or joint bleeds. That is why their clinical presentation is indistinguishable. To tell them apart, you need specific factor assays: Hemophilia A is due to factor VIII deficiency, while Hemophilia B is due to factor IX deficiency. Lab tests also show a prolonged aPTT with a normal PT in both conditions, not a normal aPTT. Remember that both are X-linked, so females are usually carriers rather than predominantly affected.