General Pathology USMLE Step 1 Practice Question
A 5 year old boy is brought to the emergency department because of decreased urine output and lethargy 5 days after an episode of bloody diarrhea from undercooked beef. He is pale and has scattered petechiae. Laboratory studies show thrombocytopenia, elevated creatinine, elevated LDH, and schistocytes on blood smear. Which of the following mechanisms most likely triggered his illness?
Answer choices
- ALoss of factor V activity
- BProtein C deficiency
- CShiga toxin mediated endothelial damageCorrect answer
- DADAMTS13 autoantibody
- EComplement factor C5 deficiency
- FComplement-mediated endothelial injury from factor H deficiency (atypical HUS)
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