A 15 year old boy is brought for recurrent jaundice and fatigue. He has had multiple episodes of pigmented gallstones, and his mother had a splenectomy at age 20. Examination shows scleral icterus and splenomegaly. Peripheral smear shows numerous spherocytes, and osmotic fragility is increased. Which of the following is the most likely underlying defect?
- A)Defect in beta globin chain synthesis
- B)Deficiency of spectrin or ankyrin in the red cell membrane skeletonGABARITO
- C)Deficiency of pyruvate kinase in erythrocytes
- D)Autoimmune destruction of red cells by IgM
- E)Absence of CD55 and CD59 on blood cells
Explicação
Deficiency of spectrin or ankyrin in the red cell membrane skeleton is correct. Hereditary spherocytosis is caused by defects in red cell membrane proteins such as spectrin, ankyrin, band 3, or protein 4.2. The result is loss of membrane surface area, spherocy... Ver explicação completa e trilha adaptativa →