Hematology Oncology · Year 2 · from Hematology Oncology
Case 2: Beta-Thalassemia Major
Patient Presentation
Demographics: 8-year-old male of Mediterranean descent
Chief Complaint: Routine transfusion clinic visit
History of Present Illness: The patient was diagnosed with beta-thalassemia major at 18 months of age when he presented with severe anemia and failure to thrive. He has been on a chronic transfusion program, receiving packed red blood cells every 3-4 weeks to maintain pre-transfusion hemoglobin above 9 g/dL. He is on deferasirox for iron chelation. His parents are concerned about his short stature compared to peers.
Physical Examination:
- Vital signs: BP 100/65, HR 90, RR 18, Temp 36.8C
- General: Small for age, appears younger than stated age
- HEENT: Frontal bossing, prominent maxillary bones (chipmunk facies)
- Cardiac: Grade II/VI systolic murmur
- Abdomen: Hepatomegaly (4 cm below costal margin), splenomegaly (6 cm below costal margin)
- Growth: Height and weight below 5th percentile
Workup and Results
Complete Blood Count (pre-transfusion):
- Hemoglobin: 8.8 g/dL
- MCV: 68 fL
- RDW: 22%
- Reticulocyte count: 4%
Hemoglobin Electrophoresis:
- HbF: 95%
- HbA2: 5%
- HbA: 0%
Iron Studies:
- Ferritin: 2,400 ng/mL (elevated despite chelation)
- Transferrin saturation: 85%
Monitoring Labs:
- Cardiac MRI T2*: 15 ms (borderline cardiac iron loading)
- Liver iron concentration: 8 mg/g dry weight (elevated)
Genetic Testing:
- Homozygous for beta-zero thalassemia mutation
Diagnosis
Beta-Thalassemia Major (Cooley's Anemia) with Iron Overload
Key features:
- Absent beta-globin production (beta-zero/beta-zero)
- Transfusion-dependent anemia
- Iron overload requiring chelation
- Classic skeletal changes from marrow expansion
- Growth delay from chronic anemia and iron overload endocrinopathy
Treatment Plan
- Transfusion therapy:
- Continue regular transfusions every 3-4 weeks
- Target pre-transfusion Hgb 9-10.5 g/dL
- Use leukoreduced, phenotypically matched blood
- Iron chelation intensification:
- Increase deferasirox dose
- Consider combination therapy (deferasirox + deferoxamine) for cardiac iron
- Target ferritin < 1,000 ng/mL, cardiac T2* > 20 ms
- Monitoring:
- Annual cardiac MRI T2* for cardiac iron
- Annual liver MRI for hepatic iron
- Endocrine evaluation (growth hormone, thyroid, glucose)
- DEXA scan for bone density
- Curative options:
- HLA typing for potential matched sibling donor transplant
- Discuss gene therapy clinical trials
Teaching Points
- Beta-thalassemia major presents in infancy as HbF declines and beta-chain deficiency manifests
- Without transfusion, severe anemia triggers massive marrow expansion causing skeletal deformities
- Chronic transfusion leads to iron overload - the major cause of morbidity without chelation
- Cardiac iron (measured by T2* MRI) is the critical determinant of survival
- Allogeneic stem cell transplant is curative in young patients with matched donors
- Gene therapy (betibeglogene autotemcel) now FDA-approved as curative option