Coagulation Disorders USMLE Step 1 Practice Question
A 45-year-old man with cirrhosis presents with epistaxis and easy bruising. Vital signs: BP 128/76, HR 92, RR 16, Temp 37°C, SpO2 98%. He denies recent anticoagulant use. Laboratory studies reveal PT 18 seconds (normal 12-14), aPTT 45 seconds (normal 25-35), platelet count 75,000/µL, fibrinogen 120 mg/dL (normal 200-400), and albumin 2.8 g/dL. Which of the following best explains the primary cause of his coagulopathy?
Answer choices
- AHeparin-induced thrombocytopenia
- BVitamin K deficiency alone
- CImmune-mediated platelet destruction
- DDisseminated intravascular coagulation
- EImpaired hepatic synthesis of clotting factorsCorrect answer
- FAntithrombin III deficiency from urinary losses
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