Week 231 - Anaemia:

Question 1

Week 231 - Anaemia: What are the causes of microcytic anaemia?

Answer 1

• Thalassaemia
• Iron Deficiency
• Anaemia of chronic disease

Question 2

Week 231 - Anaemia: What does Ferritin represent?

Answer 2

Intracellular iron stores, but it also an acute phase protein.

Question 3

Week 231 - Anaemia: What are the broad causes of iron deficiency?

Answer 3

• Poor intake
• Reduced absorption
• Increased losses
• Increased demand

Question 4

Week 231 - Anaemia: What can cause reduced absorption of iron?

Answer 4

• Abnormal bowel - Crohns, Coeliac, Gastritis.
• Lack of Bowel - Bypass, resection.
• Interference - PPIs, Calcium supplements, Thalins, Chocolate

Question 5

Week 231 - Anaemia: What can cause increased losses of iron?

Answer 5

• Menstruation
• Occult blood loss
• Haemolysis
• Haemodialysis

Question 6

Week 231 - Anaemia: What is the life span of an erythrocyte?

Answer 6

120 days

Question 7

Week 231 - Anaemia: Outline Erythropoiesis.

Answer 7

1) Erythropoietin (EPO) is synthesized primarily from the renal cortex.
2) EPO stimulates stem cells within the bone marrow to differentiate into erythroid precursors.
3) EPO continues to stimulate primitive erythroid cells in the bone marrow and induce maturation.
4) Macrophages surround these cells in the bone marrow to become erythroblastic islands.

Question 8

Week 231 - Anaemia: Production of erythropoietin is triggered by what?

Answer 8

Tissue hypoxia (Oxygen tension within the tubules of the kidney)

Question 9

Week 231 - Anaemia: How does chronic renal disease cause anaemia and what is the morphology of it?

Answer 9

The production of EPO is reduced as this takes place in the renal cortex. There is therefore a reduction in red blood cell production.
- The cells will be normocytic.

Question 10

Week 231 - Anaemia: What is the cell line of erythropoiesis?

Answer 10

1) Marrow
2) Pronormoblast
3) Normoblast
4) Reticulocytes
5) Erythrocytes

Question 11

Week 231 - Anaemia: What is a reticulocyte? Why are they important?

Answer 11

• ‘Teenager’ of erythropoiesis.
• Raised following haemorrhage, haemolytic anaemia.
• They provide an excellent measure of red cell production and the age of the red cell population.

Question 12

Week 231 - Anaemia: Why does iron deficiency lead to microcytic anaemia?

Answer 12

• Iron is the rate limiting step of erythropoiesis.

* Without adequate iron, the cells will divided more leading to a reduced size.

Question 13

Week 231 - Anaemia: Why does B12 and folate deficiency lead to a macrocytic anaemia?

Answer 13

• These are key building blocks for DNA synthesis and cell mitoses.
• Inadequate amounts of B12 and folate lead to less divisions resulting in erythrocytes being pumped into blood at a larger size.

Question 14

Week 231 - Anaemia: What would the iron profile be in someone with iron deficiency? (Serum iron, TIBC, Ferritin, Serum soluble transferrin receptors)

Answer 14

• Serum Iron - Reduced
• TIBC (total iron-binding capacity) - Increase since the body works hard to bind any free iron.
• Ferritin - Reduced
• Serum soluble transferrin receptors - Increased

Question 15

Week 231 - Anaemia: How is vitamin B12 absorbed?

Answer 15

• Stomach - B12 binds with intrinsic factor to form a complex.
• Terminal ileum - Travels through the small intestine where it is absorbed in the terminal ileum.

Question 16

Week 231 - Anaemia: What is pernicious anaemia?

Answer 16

• This is the leading cause of B12 deficiency.
• IgG autoantibodies target gastric parietal cells which produce intrinsic factor, which therefore reduces the amount of IF-B12 complexes that can be formed and absorption is reduced.

Question 17

Week 231 - Anaemia: What are the proteins that make up the red blood cell membrane?

Answer 17

Spectrin, actin, Protein 4.1 and ankyrin.

Question 18

Week 231 - Anaemia: What is hereditary spherocytosis?

Answer 18

• Abnormal spectrin gene (Important protein in red blood cell membrane)
• Causes the membrane to malfunction.
• The sheer forces of the microcirculation cause the cell to deform.
• The cell becomes a spherocyte, which is a small, rigid, spherical erythrocyte.
• The cell can then haemolyse causing anaemia.

Question 19

Week 231 - Anaemia: What is LDH and what is it’s significance?

Answer 19

• Lactate Dehydrogenase
• Enzyme that is released on the destruction of red cells, therefore high concentrations in blood provides an indicator for haemolysis.

Question 20

Week 231 - Anaemia: The breakdown of what forms bilirubin?

Answer 20

Haem

Question 21

Week 231 - Anaemia: What are the two key compensatory mechanisms of anaemia and how do they present?

Answer 21

• Cardiac compensation - Increased stroke volume and heart rate, this can present with palpitations, tachycardia and heart murmurs.
• Skin - Pallor can occur as vasodilation occurs to redistribute oxygen to the vital organs.

Question 22

Week 231 - Anaemia: Why does anaemia that has a rapid onset cause more problems than slower progressive anaemia?

Answer 22

There is less time for the oxygen dissociation curve and cardiovascular system to adapt.

Question 23

Week 231 - Anaemia: What nail changes do you get anaemia and what type is it specific to?

Answer 23

Koilonychia (Spoon Nails) - Iron deficient anaemia

Question 24

Week 231 - Anaemia: What is atrophic glossitis?

Answer 24

• Red large swollen tongue.

* It is a specific sign that is seen in both Vitamin B12 and folate deficiency.

Question 25

Week 231 - Anaemia: What is angular stomitis?

Answer 25

* Fissuring at the corners of the mouth. | * Specific sign of both vitamin B12 and folate deficiency.

Question 26

Week 231 - Anaemia: What are the causes of macrocytic cells?

Answer 26

* In terms of anaemia - B12 and folate deficiency. * Alcohol is the most frequent cause in general. • Macrocytic cells may also be present in Liver disease, Hypothyroidism, Hypoxia, Cytotoxic drugs, pregnancy.

Question 27

Week 231 - Anaemia: What is the function of the haemopoietic system?

Answer 27

* Transport - Cells, oxygen, hormones, drugs. * Surveillance - Cells, cytokines, proteins. * Temperature regulation

Question 28

Week 231 - Anaemia: What are the component parts of the haemopoietic system?

Answer 28

* Bone - Scaffold and cells. * Blood - Vessels and cells * Lymph - Vessels, cells, Spleen and thymus.

Question 29

Week 231 - Anaemia: What is responsible for the differentiation of red blood cells and where does it come from?

Answer 29

• EPO (Erythropoietin) - Renal cortex.

Question 30

Week 231 - Anaemia: What is responsible for the differentiation of white blood cells and where does it come from?

Answer 30

• GCSF, GMCSF - Granulocyte colony stimulating factor and granulocyte-macrophage colony stimulating cells - Both are released from the marrow stomal cells.

Question 31

Week 231 - Anaemia: What is responsible for the differentiation of platelets and where does it come from?

Answer 31

• TPO (Thrombopoietin) - Marrow stomal cells.

Question 32

Week 231 - Anaemia: Lymphoid stem cells give rise to which mature cells?

Answer 32

* Lymphocytes (B+T). | * Natural killer cells.

Question 33

Week 231 - Anaemia: Myeloid progenitor cells give rise to which mature cells?

Answer 33

* Red cells, platelets. * Monocytes, Neutrophils * Eosinophils, Basophils.

Question 34

Week 231 - Anaemia: During fetal development where does haematopoiesis take place?

Answer 34

AGM region | - Aorta, gonad, mesonephros.

Question 35

Week 231 - Anaemia: What are the side effects of oral iron?

Answer 35

* Nausea and vomiting * Diarrhoea * Constipation * Dyspepsia * Black faeces

Question 36

Week 231 - Anaemia: What are the common features of anaemia?

Answer 36

* Fatigue * Dyspnoea * Palpitations * Headache * Tinnitus * Anorexia and bowel distubrance