Normal haemoglobin - 2 alpha and 2 beta chains

Pathophysiology

Autosomal recessive conditions related to a genetic defect in the protein chains making up haemoglobin

The defective synthesis of globin chains in thalassaemia leads to imbalanced globin chain production, the greater the imbalance the worse the phenotype

• causes precipitation of the excess globin chains within the red cell precursors resulting in ineffective erythropoeisis
• Precipitation of globin chains in mature red cells = haemolysis
  • RBC are more fragile and break down more easily.
  • More RBC to be collected and broken down by the spleen = splenomegaly
  • Bone marrow expands to produce extra RBC compensating for the chronic anaemia = Susceptibility to fractures and prominant features such as pronounced forehad and malar eminences

Types

Alpha thalassaemia

Beta thalassaemia

*Varying degrees of anaemia depend on the type and mutation

PC

• Fatigue
• Pallor
• Jaundice
• Gallstones
• Splenomegaly
• Poor growth and development
• Pronounced forehead and malar eminences