II. Epidemiology: Ethnicity
- Southern Italy and Mediterranean islands (0.1% Incidence)
- Central Africa
- Southeast Asia
III. Pathophysiology
- See Hemoglobin Production
- Autosomal Recessive trait affecting single gene on each of the two Chromosome 11
- Results in decrease of absence of Hemoglobin beta chains and excess of alpha chains
- Images
IV. Types: Beta Thalassemia
- Beta Thalassemia Trait
- One gene defect on Chromosome 11 (Heterozygote)
- Typically asymptomatic
- Beta Thalassemia Intermedia
- Two gene defect on Chromosome 11
- Mild to moderate decrease in beta globin synthesis, and may require intermittent Blood Transfusions
- Moderate symptoms (less than in Beta Thalassemia Major) - see below
- Beta Thalassemia Major (Cooley's Anemia)
- Two gene defect on Chromosome 11
- Severe decrease in beta globin synthesis
- Severe symptoms (see below)
- Associated with Gallstones, skeletal abnormalities, Hepatosplenomegaly, Jaundice, pallor
- Onset of symptoms by 6 months of age after Hemoglobin F (fetal Hemoglobin) levels fall
- Lifelong Blood Transfusions required after 6 months of age
V. Types: Beta Thalassemia with Hemoglobinopathy
-
Hemoglobin C Disease (HbC)
- Beta Thalassemia with mildly reduced Beta Globin Synthesis (HbC/B+)
- Mild Anemia may be present
- Beta Thalassemia with severely reduced Beta Globin Synthesis (HbC/B0)
- Beta Thalassemia with mildly reduced Beta Globin Synthesis (HbC/B+)
-
Hemoglobin E Disease (HbE)
- Beta Thalassemia Trait (HbE/B+)
- Mild to moderate Anemia
- Beta Thalassemia (HbE/B0)
- Similar to Beta Thalassemia Intermedia and major
- May be transfusion dependent
- Beta Thalassemia Trait (HbE/B+)
-
Hemoglobin S Disease (HbS)
- Beta Thalassemia with mildly reduced Beta Globin Synthesis (HbS/B+)
- Beta Thalassemia with severely reduced Beta Globin Synthesis (HbS/B0)
- Nearly identical to Sickle Cell Anemia (HbSS)
- Low MCV may distinguish HbS/B0 from HbSS
VI. Findings
- See Thalassemia
- Typically asymptomatic outside of Beta Thalassemia Major
VII. Labs
- See Thalassemia
-
Hemolytic Anemia
- Typically more severe Anemia than with Alpha Thalassemia
-
Hemoglobin Electrophoresis
- See Thalassemia for findings
VIII. Management
- See Thalassemia
IX. Prevention
- See Thalassemia
X. Prognosis: Life Expectancy
- See Thalassemia
XI. Complications
- See Thalassemia