Thalassaemia Flashcards
What is the aetiology and pathology of thalassaemia?
Reduced or absent globin chains due to mutation/deletion
What is the inheritance of thalassaemia?
Autosomal dominant
What type of thalassaemia is incompatible with life?
Homozygous alpha thalassaemia
What is a sign of alpha thalassaemia?
Hydrops fetalis
What is hydrops fetalis?
Swollen liver and abdomen of the new born
What are the 3 types of beta thalassaemia?
Major
Intermedia
Minor (thalassaemia trait)
What is beta thalassaemia major?
Transfusion dependent thalassaemia
Homozygous beta thalassaemia
NO BETA CHAINS PRODUCED
What is beta thalassaemia intermedia?
Non-transfusion dependent thalassaemia
What physiological condition may increase the effects of beta thalassaemia trait?
Pregnancy
Typical presentation?
” 8 month old boy of meditteranian origin presents with progressive abdominal swelling and hepatosplenomegaly. O/e he is pale, jaundiced and has parietal bossing. “
How is beta thalassaemia diagnosed?
Picked up at birth –> complete lack of HbA
How does beta thalassaemia present if not diagnosed at birth?
- Large head
- > parietal bossing
- Chipmunk facies
- Jaundice and severe anaemia (extrinsic haemolysis)
- Abdo swelling
- Bony lesions from bone marrow expansion
Why does extrinsic haemolysis occur in beta thalassaemia?
Spleen and reticuloendothelial system detect abnormal RBCs and destroy them –> hepatosplenomegaly
What investigations can be done for beta thalassaemia?
FBC
Blood smear
Reticulocyte count
What is shown on blood smear?
Tear drop cells
Treatment of beta thalassaemia major?
Chronic transfusion
Iron chelation
What is iron chelation?
Done due to iron overload from chronic transfusion
What iron chelation agents are used?
Desferroxamine IV
Desferasirox Oral
What is treatment of other thalassaemias?
Observation
