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?
- A)Reduced spectrin anchoring to the red cell membrane
- B)Defective platelet adhesion due to loss of GpIb
- C)Autoimmune destruction of red blood cells by IgG antibodies
- D)Deficiency of glucose-6-phosphate dehydrogenase
- E)Absent or markedly reduced beta-globin synthesisGABARITO
Explicação
Beta-thalassemia major is the correct answer because symptoms begin after about 6 months of age when fetal hemoglobin declines and beta-globin is needed. Absent or markedly reduced beta-globin synthesis causes severe ineffective erythropoiesis, transfusion dep... Ver explicação completa e trilha adaptativa →