thalassemia

Question 1

what are the constitute of a normal molecule of haemoglobin A ?

Answer 1

2 normal genes of beta haemoglobin with 4 alphas to make haemoglobin A

Question 2

how many genes make up two alpha genes ?

Answer 2

4 genes

Question 3

in alpha thalassemia :

one gene missing on one allele

Answer 3

alpha + heterozygote

Question 4

in alpha thalassemia :

one gene missing on each allele ?

Answer 4

alpha+homozygous

Question 5

in alpha thalassemia :

two genes missing on one allele ?

Answer 5

alpha zero thalassemia

Question 6

in alpha thalassemia :

3 genes missing ?

Answer 6

haemoglobin H disease

Question 7

in alpha thalassemia:

4 genes missing ?

Answer 7

alpha thalassemia major of hydrops fetalis which is incompatible with life

Question 8

what is the genetic makeup of someone who has thalassemia intermedia ?

Answer 8

triplicated alpha plus beta thalassemia trait

Question 9

what are the genetic modifiers of beta thalassemia ?

Answer 9

XMN polymorphism

co-inheritance of alpha deletions

Question 10

what are the clinical effects of thalassemia ?

Answer 10

reduced haemoglobin production
inc RBC
hypochromic microcytic anemia

Question 11

what are the side effects and complications of thalassemia ?

Answer 11

of the disease :
osteoporosis 
extra medullary hematopoesis
of the treatment:
cardiac/liver/pancreatic 
endocrine

Question 12

what must be given once iron levels start to increase ?

Answer 12

chelating agents

Question 13

alpha thalassemia trait and HbH disease blood results ?

Answer 13

MCV low
MCH low
RBC high
HbA2 low

Question 14

blood picture in beta thalassemia trait ?

Answer 14

Hb is low 
MCV is low 
MCH is low 
RBC is high 
HbA2 is high

Question 15

blood picture in beta thalassemia major ?

Answer 15

Hb is low 
MCV is low 
MCH is low 
RBC high 
only haemoglobin F is present

Question 16

what is the standard therapy for thalassemia major ?

Answer 16

transfuse every 3-4 weeks allow for mean haemoglobin too reach 12g/dl
chelate - desferrioxamine

Question 17

what is the clinical classification of beta thalassemia ?

Answer 17

beta thalassemia trait or minor : heterozygote

beta thalassemia major :
homozygote

beta thalassemia intermedia:
mild homozygote

Question 18

what is the presentation of a patient that only has the beta thalassemia trait ?

Answer 18

microcytic but not anemia
raised haemoglobin a2

Question 19

what is the presentation of beta thalassemia major ?

Answer 19

severe transfusion dependent
presents 1-2 months after birth
expansion of the bone marrow
cardiac death due to iron overload

Question 20

how do we monitor therapy for iron overload ?

Answer 20

serum ferritin
liver iron concentration
organ damage

Question 21

when to suspecct thalassemia initially ?

Answer 21

microcytic hypochromic anemia with increased RBC