Mind maps Thalassaemia

Question 1

What is it

Answer 1

Genetic conditions, inherited in an autosomal recessive pattern, the produce a picture of microcytic anaemia due to a problem in globin chain production.
This subsequently alters haemoglobin synthesis.

Question 2

Types

Answer 2

Alpha-thalassaemia

Beta-thalassaemia

Question 3

Populations affected by alpha thalassaemia

Answer 3

More prominent in African and Asian populations

Question 4

Causes of alpha thalassaemia

Answer 4

Decreased Alpha-Globin (a-globin) synthesis due to a-globin gene mutation on chromosome 16
This results in excess Beta-globin (b-globin) production

Question 5

Variation in cause of a-thalassaemia

Answer 5

Any number between 1 and 4 genes may be deleted:
1 gene deleted = no significant anaemia
2 = trait disease
3 = HbH disease
4 = death - Bart's hydrops fetalis

Question 6

Populations affected by beta thalassaemia

Answer 6

More prominent in European populations

Question 7

Causes of b-thalassaemia

Answer 7

Point mutation in beta-globin chain on chromosome 11

Results in excess a-globin production

Question 8

3 traits that b-thalassaemia can be subdivided into

Answer 8

Minor = usually asymptomatic; carrier state; mild anaemia
Intermediate = moderate anaemia; no blood transfusions required
Major = Cooley's anaemia; abnormalities in all b-globin chains results in severe anaemia

Question 9

What sign is characteristic of major beta-thalassaemia

Answer 9

Cranial bossing seen due to extramedullary haematopoiesis

Question 10

What type of anaemia is thalassaemia

Answer 10

Microcytic, hypochromic

Question 11

Investigations for either alpha or beta thalassaemia

Answer 11

Blood films (target cells may be seen in alpha)
FBC
Hb electrophoresis
High performance liquid chromatography
Radiology - X-ray for bone abnormalities e.g. frontal bossing

Question 12

What is expected on Hb electrophoresis of thalassaemia

Answer 12

High HbA2

High HbF

Question 13

What is assessed/expected on FBC of thalassaemia

Answer 13

Microcytic, hypochromic anaemia
Low MCV
Low MCH
Ferritin normal
Iron normal

Question 14

Conservative treatment

Answer 14

Patient education

Genetic counselling

Question 15

Medical treatment

Answer 15

Management of a or b is based on patient symptoms and overall state of health
Transfusions are usually required with Hb <7g/dL or when patient is highly symptomatic
Patients who have repeated blood transfusions are at risk of haemochromatosis and therefore iron chelation therapy

Question 16

Patients who have repeated blood transfusions are at risk of haemochromatosis and therefore what therapy?

Answer 16

Iron chelation therapy

e.g. desferroxamine

Question 17

Surgical treatment

Answer 17

Splenectomy

Stem cell transplant

Question 18

Complications

Answer 18

Iron overload
Splenomegaly
Increased infection risk
Heart failure
Arrhythmias
Bone abnormalities e.g. cranial bossing
Gallstones