Medical Emergencies · single question
Which laboratory test is used to screen for hemophilia (intrinsic coagulation pathway)?
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Correct answer: A. Partial thromboplastin time (PTT/aPTT)
- A. Correct. Hemophilia A/B (factor VIII/IX deficiency) prolongs the intrinsic pathway, measured by the (activated) partial thromboplastin time (PTT/aPTT).
- B. PT/INR evaluates the extrinsic pathway (and warfarin/vitamin-K-dependent factors).
- C. Bleeding time assesses platelet function/primary hemostasis.
- D. Platelet count is normal in hemophilia (a coagulation-factor disorder).
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