Clinical scenario: thalassemia | transfusion goal
A 16-month-old boy is brought with progressive pallor, poor weight gain, and increasing abdominal distension. He has required two blood transfusions over the past 4 months. Examination reveals frontal bossing, maxillary hypertrophy, marked splenomegaly (8 cm below the costal margin), and hepatomegaly. There is no history of jaundice in the neonatal period.
Investigations:
- Hemoglobin: 5.8 g/dL
- MCV: 61 fL
- Reticulocyte count: 7%
- Peripheral smear: Severe microcytosis, hypochromia, target cells, nucleated RBCs
- Serum ferritin: 220 ng/mL
- Hb electrophoresis:
- HbF 92%
- HbA Absent
- HbA₂ 8%
The child is started on a regular transfusion program.
Which of the following is the primary therapeutic goal of maintaining the pre-transfusion hemoglobin around 9–10.5 g/dL?
A. Prevent iron overload from repeated transfusions
B. Suppress ineffective erythropoiesis and prevent skeletal deformities
C. Normalize serum ferritin concentration
D. Reduce the risk of alloimmunization
E. Eliminate the need for iron chelation
Correct answer & Explanation:
Correct Answer: B. Suppress ineffective erythropoiesis and prevent skeletal deformities
Explanation:
This child has transfusion-dependent β-thalassemia major, characterized by:
- Severe anemia beginning in infancy
- HbA absent
- Predominantly HbF
- Massive ineffective erythropoiesis
- Bone marrow expansion causing frontal bossing and maxillary hypertrophy
- Hepatosplenomegaly
The purpose of maintaining the pre-transfusion hemoglobin between 9 and 10.5 g/dL is to:
- Suppress erythropoietin production
- Reduce ineffective erythropoiesis
- Prevent bone marrow expansion
- Prevent facial bone deformities and pathological fractures
- Improve normal growth and development
- Reduce extramedullary hematopoiesis and splenomegaly
This is the cornerstone of modern transfusion therapy in thalassemia major.
Why the other options are incorrect
A. Prevent iron overload
- Iron overload results from repeated transfusions and is prevented by iron chelation, not by maintaining a specific hemoglobin level.
C. Normalize serum ferritin
- Ferritin reflects iron burden and is managed through chelation therapy.
D. Reduce alloimmunization
- Alloimmunization is minimized by extended antigen matching, not by higher hemoglobin targets.
E. Eliminate iron chelation
- Every chronically transfused patient eventually requires iron chelation.
High-yield pearl (Exam Favorite)
Question: Why are regular transfusions given in β-thalassemia major?
Best answer: To suppress ineffective erythropoiesis, thereby preventing bone marrow expansion, skeletal deformities, growth failure, and extramedullary hematopoiesis—not simply to correct anemia.
