Anemias USMLE Step 1 Practice Question
A 34-year-old man presents with episodic dark urine in the morning and abdominal pain. He has a history of a hepatic vein thrombosis. Laboratory studies show hemolytic anemia with elevated lactate dehydrogenase. Flow cytometry demonstrates absent CD55 and CD59 on blood cells. Which of the following is the most likely diagnosis?
Answer choices
- AAutoimmune hemolytic anemia
- BG6PD deficiency
- CParoxysmal nocturnal hemoglobinuriaCorrect answer
- DMicroangiopathic hemolytic anemia
- EHereditary spherocytosis
- FCold agglutinin disease
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