Red cell disorders

Question 1

what are RBCs made of?

Answer 1

Hb- made of globin and iron
enzymes
cell membrane

Question 2

Give examples of haemoglobinopathies

Answer 2

Sickle cell disease

thalasaemia

Question 3

give an exmaple of a disorder of quality of RBCs

Answer 3

sickle cell disease

Question 4

give an example of a disorder of quantity in RBCs

Answer 4

thalassaemia

Question 5

what are the foetal Hb chains?

Answer 5

2 alpha

2 gamma

Question 6

what is HbA?

Answer 6

normal adult haemaglobin - 2 alpha and 2 beta

Question 7

what is HbA2?

Answer 7

a variant of adult haemaglobin - 2 alpha and 2 delta chains

Question 8

what is heme?

Answer 8

iron bound to a porphyrin ring

Question 9

pts who have sickle cell disease can still get malaria true or false?

Answer 9

true

Question 10

what is combined heterozygosity?

Answer 10

when there is a mutation in one gene and a mutation in another gene but together this causes the full blown disease

Question 11

Give an example of combine heterozygosity when it comes to sickle cell disease

Answer 11

HbS and HbC

Question 12

people from which countries are affected by sickle cell anaemia?

Answer 12

Greece, Caribbean, south america, subsaharan africa, mediterranean, India

Question 13

What is the percentage change that two carrier parents will have a child with sickle cells disease?

Answer 13

25%

Question 14

what is the percentage change that two carrier parents will have a child with sickle trait?

Answer 14

50%

Question 15

What are the complications of sickle cell disease?

Answer 15

chronic haemolytic anaemia
infections 
painful crises 
splenic sequestration
acute chest syndrome 
stroke
aplastic crisis 
avascualr necrosis 
priapism
pulmonary arterial hypertension
sickle nephropathy 
ocular disease 
iron overload 
leg ulcers 
reduced life expectancy

Question 16

Name 3 acute complications of sickle cells disease

Answer 16

painful crisis
acute chest syndrome
stroke

Question 17

Name 3 chronic complications of sickle cell disease

Answer 17

renal impairment
pulmonary hypertension
joint damage

Question 18

Name three disease modifying treatments offered to people with sickle cell disease

Answer 18

transfusion
hydroxycarbamide
stem cell transplant

Question 19

What is thalassaemia?

Answer 19

Globin chain disorders resulting in diminished synthesis of one or more globin chains with consequent reduction in the haemoglobin

Question 20

People from which countries may be affected by thalasaemia?

Answer 20

mediterranean including Turkey
italy
middle east
bangladesh and india
far east and thailand
sub-saharan africa 
Yemen
Syria and Iraq

Question 21

which group of thalassaemia pts are transfusion dependent?

Answer 21

thalassaemia major

Question 22

which group with thalassaemia are asymptomatic?

Answer 22

carriers

Question 23

what are the three groups of clinical classification of thalassaemia?

Answer 23

Thal. major
Thal. intermedia
Thal. carrier

Question 24

at what age does beta thalassaemia major present?

Answer 24

6-12 months

Question 25

what symptoms may a child with beta thalassaemia major present with?

Answer 25

failure to feed restless crying pale

Question 26

What type of anaemia is thalassaemia?

Answer 26

microcytic

Question 27

What will the blood results show with someone with beta Thalassaemia Major?

Answer 27

low Hb very low MCV very low MCH (ie the average mass of Hb per RBC) nucleated RBCs irregular sized (ie large and small RBCs) that are very pale normal ferritin

Question 28

how is thalassaemia major treated?

Answer 28

``` Regular transfusion Iron chelation Endocrine supplementation (fertility) Bone health Psychological support ```

Question 29

How is thalassaemia major monitored?

Answer 29

Ferritin Cardiac and Liver MRI Endocrine testing (Gonadal function, Diabetes screening, Growth & puberty, Vit D, Calcium, PTH, Thyroid) Dexa scanning

Question 30

What are the complications of iron overload?

Answer 30

``` hepatic fibrosis and cirrhosis cardiac arrhythmia hypogonadism diabetes hypothyroidism hypoparathyroidism cardiac failure death ```

Question 31

Describe the inheritance of alpha thalassaemia

Answer 31

inherit two copies from mother and two copies from father | need to inherit at least 3 faulty copies out of the 4 to get alpha thalassaemia

Question 32

Where are the distributions of alpha 0 thalassaemia confined to?

Answer 32

eastern mediterranean ie Greece | far east

Question 33

How are membranopathies inherited?

Answer 33

autosomal dominant

Question 34

name two membranopathies

Answer 34

Spherocytosis & elliptocytosis

Question 35

what is a membranopathy in RBCs?

Answer 35

Deficiency of red cell membrane proteins caused by a variety of genetic lesions

Question 36

what are the signs of a RBC membranopathy?

Answer 36

Neonatal jaundice Mild to moderate haemolytic anaemia with occasional exacerbations during infection Gallstones

Question 37

what an be used to treat membranopathies?

Answer 37

Folic acid and splenectomy in selected cases

Question 38

What happens in pts who have haemolytic anaemias and get infected with parvovirus?

Answer 38

slapped cheek syndrome Leads to decreased RBC production Dramatic Hb drop in patients who already have reduced red cell lifespan.

Question 39

what are the 2 most common enzymopathies of RBCs?

Answer 39

G6PD deficiency and pyruvate kinase deficiency

Question 40

what does enzymes normally do in RBCs?

Answer 40

provide fuel for the red cell | allows redox reactions to occur

Question 41

how do enzyme deficiencies damage red cells?

Answer 41

oxidative damage due to lack of redox ability

Question 42

Which communities are most likely to have G6PD?

Answer 42

African, Middle Eastern, Mediterranean, S. Asian

Question 43

how is G6PD inherited?

Answer 43

X-linked | but women can be affected by this condition due to lyonisation

Question 44

What are the symptoms/signs of a crisis from G6PD?

Answer 44

haemolysis, jaundice, anaemia.

Question 45

what are the drugs that can cause interactions with G6PD?

Answer 45

``` Primaquine Sulphonamides Nitrofurantoin Quinolones Dapsone ```

Question 46

what is the most common inherited disease in england?

Answer 46

sickle cell disease