Hereditary anaemias (Red cells 1)

Question 1

what substances are required for red cell production?

Answer 1

metals:
- iron
- copper
- cobalt 
- manganese 
vitamins;
- vita B12
- folic acid
- thiamine 
- vit B6, C and  E
amino acids 
erythropoietin, GM CSF, androgens, thyroxine

Question 2

what its he reticuloendothelial system ?

Answer 2

various cells found throughout the body whose primary function is to remove damaged or dead cells

Question 3

where does red cell breakdown occur?

Answer 3

reticuloendothelial system

Question 4

what are red cells broken own into?

Answer 4

haem - iron and bilirubin

globin - amino acids

Question 5

what is responsible for maintaing red cell shape and deformability?

Answer 5

skeletal proteins

Question 6

what is responsible for hereditary spherocytosis?

Answer 6

defects in a structural proteins

defect in cell membrane

Question 7

are common forms of hereditary spherocytosis autosomal dominant or recessive?

Answer 7

autosomal dominant

Question 8

what is the condition inn which the red cells are spherical?

Answer 8

hereditary spherocytosis

Question 9

what is the clinical presentation of hereditary spherocytosis?

Answer 9

anaemia
jaundice (neonatal)
splenomagely
pigment gallstones

Question 10

what is the treatment for hereditary spherocytosis?

Answer 10

folic acid
tranfusion
splenectomy if anaemia very severe

Question 11

what is G6PD deficiency?

Answer 11

deficiency in glucose 6 phosphate dehydrogenase which is required to protect red cell proteins (haemoglobin) from oxidative stress
red cells are then vulnerable o oxidative stress

Question 12

what does G6PD deficiency confer protection against?

Answer 12

malaria

Question 13

what is the clinical presentation of 6GPD deficiency?

Answer 13

neonatal jaundice 
splenomegaly 
pigment gallstones
drug, broad bean or infection precipitated jaundice and anaemia 
- intravascular haemolysis 
- haemoglobinuria

Question 14

what can trigger haemolysis in G6PD deficiency?

Answer 14

infection 
acute illness i.e. DKA 
drugs;
- antimalarials 
- sulphonamides and sulphides 
- Nitrofurantoin
- Aspirin 
- Antihelminthics i.e. B-naphthol 
- vitamin K analogues
- probenecid
- methylene blue

Question 15

what is the bohr effect?

Answer 15

oxyhemoglobin saturation increases when patients PH increase, temp decreases

oxyhemoglobin saturation decreases when a patients PH decreases, temp and C02 increases

haemoglobin gives up oxygen (decreasing oxyhemoglobin saturation) depending on tissues needs

Question 16

what is the normal Hg range for male and females?

Answer 16

male: 135-170 g/L
female: 120-160 g/L

Question 17

what is the defect in thalassaemia?

Answer 17

reduced or absence of globin chain production resulting in abnormalities of haemoglobin synthesis

Question 18

what is the defect in sickle cell disease?

Answer 18

mutations leading to structurally abnormal globin chain resulting in abnormalities of haemoglobin synthesis

Question 19

are haemoglobinopathies autosomal dominant or recessive?

Answer 19

all recessive

Question 20

what are the clinical presentations of sickle cell disease?

Answer 20

painful vaso-occlusive crises
- bone 
chest crisis - pulmonary infarcts = pneumonia
stroke 
increased infection risk 
- hyposplenism 
chronic haemolytic anaemia 
- gallstones
- aplastic crisis 
sequestration crisis
- spleen 
- liver

Question 21

how can chronic haemolysis cause gallstones?

Answer 21

chronic haemolysis leads to an increase in billirubin excreted into the billiard tract which in turn can cause gallstones

Question 22

how do you manage painful crisis in sickle cell?

Answer 22

give analgesia within 30 mins of presentation
hydration
oxygen
consider antibiotics

Question 23

what life long prophylaxis should people with sickle cell be given?

Answer 23

vaccination
penicillin and malarial prophylaxis
folic acid

Question 24

what are the management options for sickle cells disease?

Answer 24

blood transfusion
bone marrow transplant
disease modifying drugs e.g. hydroxycarbamide
gene therapy

Question 25

what type of thalassaemia is transfusion dependent?

Answer 25

beta thalassaemia major

Question 26

when does beta thalasaemia major present in life?

Answer 26

3-6 months of age

Question 27

what is the presentation of beta thalassaemia major?

Answer 27

bone deformities
splenomegaly
growth retardation
(expansion of ineffective bone marrow)

Question 28

what is the treatment for beta thalassaemia major?

Answer 28

iron chelation therapy
bone marrow transplantation
chronic transfusion

Question 29

what defect causes porphyrias?

Answer 29

defect in cytoplasmic steps in haem synthesis

Question 30

what defect causes sideroblastic anaemia?

Answer 30

defect in mitochondrial steps of haem synthesis

Question 31

what is anaemia?

Answer 31

reduction in red blood cells or their haemoglobin content

Question 32

what are the 3 main contents of the mature red cells (erythrocytes) ?

Answer 32

membrane
enzymes
haemoglobin

Question 33

are majority of hereditary anaemia autosomal dominant or recessive?

Answer 33

recessive

Question 34

in the average adult, what type of chains is the majority of haemoglobin composed of?

Answer 34

2 alpha and 2 beta chains

Question 35

being a carrier of thalassaemia or sickle cell protects you from what?

Answer 35

malaria