Anaemia

Question 1

What is anaemia?

Answer 1

Reduced total cell mass

Question 2

What are the normal Hb values?

Answer 2

Male <130g/L

Female <120g/L

Question 3

How is Hb concentration measured?

Answer 3

Burst the red cells and stabilise. Measure the optical density - the more red, the more absorbed, more Hb

Question 4

Other than Hb what else can be measured to determine red cell count?

Answer 4

Haematocrit

Question 5

When are Hb and Hct not useful?

Answer 5

Rapid blood loss

Haemodilution

Question 6

Define reticulocytosis

Answer 6

Normal response to anaemia is to produce more red cells

Question 7

Describe reticulocytes

Answer 7

• red cells that have just left the bone marrow
• remnants of RNA, stain purple
• blood film appears polychromatic
• up regulation takes a few days
• marker of bone marrow function

Question 8

Name the two key causes of anaemia

Answer 8

• decreased production

- increased loss/destruction

Question 9

What can cause decreased production of red blood cells?

Answer 9

Hypoproliferation - reduced erythropoiesis

Maturation abnormality - erythropoiesis present but ineffective

Question 10

Name the two subtypes of maturation abnormality

Answer 10

Cytoplasmic defect (impaired haemoglobinisation)
Nuclear defect (impaired cell division)

Question 11

What causes increased loss/destruction of red blood cells?

Answer 11

Bleeding/Haemolysis

Question 12

How can anaemia be described in terms of mean cell volume?

Answer 12

Microcytic

Macrocytic

Question 13

How is haemoglobin synthesised?

Answer 13

Iron from blood enters mitochondria
Fe3+ moves out of mitochondria and binds to protophorphyrin to form haem
Haem binds to globin subunits

Question 14

How does microcytic anaemia arise?

Answer 14

Hb is synthesised in the cytoplasm and requires specific building blocks. If one is missing the cells will continue to divide but will lack certain substances - small

Question 15

What do microcytic anaemia red blood cells look like?

Answer 15

Hypochromic due to little Hb

Question 16

State the causes of microcytic anaemia

Answer 16

Thalassemia - globulin subunits
Anaemia of chronic disease 
Iron deficiency 
Lead poisoning - porphyrin synthesis 
Sideroblastic - porphyrin synthesis

Question 17

How can you calculate the average Hb content in a solution?

Answer 17

Litres/2

Question 18

What transports iron?

Answer 18

Transferrin

Question 19

What stores iron?

Answer 19

Ferritin

Question 20

What should the saturation of transferrin be?

Answer 20

30-40%

Question 21

What is the best measure of iron?

Answer 21

Ferritin

Question 22

What can cause a rise in ferritin?

Answer 22

Inflammatory disease

Question 23

Name the causes of iron deficiency

Answer 23

Diet
Loss of iron - blood loss
Malabsorption (coeliac, achlorhydria)

Question 24

Where is iron absorbed?

Answer 24

Proximal small bowel (jejunum and duodenum)

Question 25

Define macrocytosis

Answer 25

Reduction in red cells that have a larger volume

Question 26

What are the two key types of macrocytic anaemia?

Answer 26

Genuine | Spurious

Question 27

Name the two types of genuine macrocytosis

Answer 27

Megaloblastic | Non-megaloblastic

Question 28

What is a megaloblastic cell?

Answer 28

An abnormally large nucleated red cell precursor with an immature nucleus

Question 29

Describe megaloblastic anaemia

Answer 29

Lack of red cells due to defects in DNA synthesis and nuclear maturation in developing precursor cells in the marrow. Reduced division, more apoptosis

Question 30

Why do megaloblastic cells still increase in size?

Answer 30

There is normal cytoplasmic development and Hb accumulation

Question 31

State the causes of megaloblastic anaemia

Answer 31

B12 deficiency Folate deficiency Drugs Inherited disorders

Question 32

How is B12 handled by the body?

Answer 32

Binds to rapid binder proteins in stomach Secretion of intrinsic factor Binds to IF to form a complex and travels to small bowel Absorbed in ileum and enters blood Binds to transcobalamin

Question 33

How long will B12 stores last?

Answer 33

2-4 years

Question 34

State the causes of B12 deficiency

Answer 34

Dietary Stomach acid/intrinsic factor Small bowel - bacteria overgrowth, coeliac, resection, IBD Inherited disorder

Question 35

What is pernicious anaemia?

Answer 35

Autoimmune condition with resulting destruction of gastric parietal cells and inability to secrete IF

Question 36

How is pernicious anaemia treated?

Answer 36

IM B12 3 monthly

Question 37

Where is folate absorbed in the body?

Answer 37

Jejunum

Question 38

How long do folate supplies last?

Answer 38

4 months

Question 39

What causes folate deficiency?

Answer 39

Diet Malabsorption Excess ultilisation - haemolysis, pregnancy, malignancy, drugs, exfoliating dermatitis

Question 40

Name the clinical features of B12/folate deficiency

Answer 40

Anaemia, weight loss, diarrhoea, infertility, sore tongue, jaundice, developmental problems

Question 41

What serious symptom can B12 deficiency cause?

Answer 41

Neurological - subacute combined degeneration of the cord

Question 42

Name two auto-antibodies that can be measured in suspected pernicious anaemia

Answer 42

Anti-gastric parietal cell | Anti- intrinsic factor

Question 43

How is anaemia treated?

Answer 43

B12 injection Folic acid tablets Red cell transfusion if life threatening

Question 44

State the causes of non-megaloblastic anaemia

Answer 44

Alcohol Liver disease Hypothyroidism Marrow failure

Question 45

What is supious macrocytosis?

Answer 45

Volume is normal but MCV is measured as high

Question 46

What can cause supious macrocytosis?

Answer 46

Reticulocytosis | Cold Agglutinins

Question 47

What is meant by cold agglutinins?

Answer 47

Abnormal protein causes clumping of RBC in infections and cancers. Usually extraordinarily high MCV and accurate sample obtained by warming blood

Question 48

Why does jaundice occur in anaemia?

Answer 48

Ineffective erythropoiesis due to intramedullary haemolysis - breakdown occurs in the bone marrow and bilirubin is released

Question 49

State the causes of normocytic anaemia

Answer 49

``` Marrow failure Hypometabolic Marrow infiltration Renal impairment Chronic disease ```

Question 50

How does inflammation lead to anaemia?

Answer 50

Activates monocytes and T cells causing release of cytokines

Question 51

What are the effects of cytokine release leading to anaemia?

Answer 51

Increase hepcidin Inhibition of erythropoietin release Inhibition of erythroid proliferation Increased red cell destruction

Question 52

When will anaemia of chronic disease be microcytic?

Answer 52

If the predominant mechanism is through hepcidin leading to reduced release of iron

Question 53

What is the key difference between iron deficiency anaemia and anaemia of chronic disease?

Answer 53

Ferritin will be normal/raised in anaemia of chronic disease