A 63-year-old man is recovering after hip replacement surgery and has been receiving unfractionated heparin. On hospital day 6 he develops pain and swelling in the left calf. Laboratory studies show that his platelet count has fallen from 260,000/mm3 to 95,000/mm3. Which of the following best describes the pathogenesis of this condition?

  1. A)Deficiency of ADAMTS13 leading to microthrombi
  2. B)Autoantibodies against factor VIII causing prolonged PTT
  3. C)Autoimmune destruction of GpIIb/IIIa in the spleen
  4. D)Direct marrow suppression by heparin
  5. E)IgG antibodies against the heparin-platelet factor 4 complex causing platelet activation and thrombosisGABARITO

Explicação

Heparin-induced thrombocytopenia is the correct answer because the platelet count fell 5 to 10 days after heparin exposure and the patient developed thrombosis rather than bleeding. Ver explicação completa e trilha adaptativa →

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