Anemias USMLE Step 1 Practice Question
A 9-month-old boy is brought to the pediatrician for pallor, poor feeding, and failure to thrive. He has required two prior blood transfusions. Examination shows frontal bossing and hepatosplenomegaly. Laboratory studies show severe microcytic anemia. Peripheral smear shows target cells and marked anisopoikilocytosis. Which of the following is the most likely mechanism of this disease?
Answer choices
- AReduced spectrin anchoring to the red cell membrane
- BDefective platelet adhesion due to loss of GpIb
- CAutoimmune destruction of red blood cells by IgG antibodies
- DDeficiency of glucose-6-phosphate dehydrogenase
- EAbsent or markedly reduced beta-globin synthesisCorrect answer
- FSickle cell disease (HbS)
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