DR Medhat MRCP

• Pathogenesis of thalassemia :
- Thalassemia results from an absence (or defect) of either :
o One or more of the 4 genes that code for the 2 α chains
o One or both of the 2 genes the code for the 2 β chains
α thalassemia.
β thalassemia.
o This finally quantitative (i.e In number) abnormality of globin chains.
o The clinical severity (syndromes) is proportional to the number of absent
genes.
α-thalassemia : (the most common Hb disease worldwide)
• C/P of Hb-H Disease :
Presented at any age , most commonly in Asians.
Most of the patients (75 %) are discovered accidentally during routine blood tests.
Only 25% of patients are symptomatic ( chronic hemolytic anemia with acute
exacerbations).
Bone deformities , recurrent blood transfusion , failure to thrive are uncommon.
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