anaemia

Question 1

how is anaemia measured clinically?

Answer 1

reduced Hb concentration

Question 2

what two factors are needed to calculate the Hb concentration?

Answer 2

red cell mass

plasma volume

Question 3

What are the normal Hb ranges?

Answer 3

men: 131 – 166 g/L
women: 110 – 147 g/L

Question 4

give an example of reduced Hb but increased red cell mass

Answer 4

drinking a lot of water

Question 5

what is quality control?

Answer 5

if you put the same sample through multiple times, you could end up with different readings

Question 6

What are the consequences of anaemia?

Answer 6

reduced o2 transport, so tissue hypoxia
compensatory changes
pathological consequences

Question 7

What are the compensatory changes in anaemia?

Answer 7

increase tissue perfusion eg tachycardia
increase o2 transfer to tissues
increased red cell production

Question 8

what are the pathological consequences of anaemia?

Answer 8

Myocardial fatty change
Fatty change in liver
Aggravate angina/claudication
Skin and nail atrophic changes
CNS cell death (Cortex and basal ganglia)

Question 9

where are red blood cells produced?

Answer 9

bone marrow

Question 10

what is the lifespan of an RBC?

Answer 10

120 days

Question 11

which organs/tissue remove RBCs from the body?

Answer 11

spleen
liver
bone marrow
blood loss

Question 12

How do we know where someone is on the red cell balance - ie the balance of RBC production and removal?

Answer 12

reticulocyte count

Question 13

What are reticulocytes?

Answer 13

immature red blood cells released from the bone marrow

Question 14

If there is too much removal of RBCs, what will happen to the reticulocyte count?

Answer 14

increase

Question 15

if there is a problem with bone marrow production of RBCs, but no problem with removal of RBCs, what will happen to the reticulocyte count?

Answer 15

decrease

Question 16

What is the first thing you look at in the results if sb is anaemic?

Answer 16

mean cell volume (the same as mean corpuscular volume) 
then split into:
microcytic 
normocytic 
macrocytic

Question 17

what is the unit for MCV?

Answer 17

femtolitres

Question 18

what are the three main causes of microcytic anaemia?

Answer 18

iron deficiency
thalassaemia
anaemia of chronic disease

Question 19

How is iron deficiency tested?

Answer 19

ferritin

Question 20

Why is ferritin not a reliable marker for iron deficiency?

Answer 20

it rises in infection, inflammation and malignancy as it is an acute phase protein

so a low ferritin is diagnostic of iron deficiency, but a raised ferritin does not rule it out

Question 21

What are the causes of iron deficiency?

Answer 21

not enough in the diet
haemmorhage incl. menorrhagia 
malabsorption 
pregnancy 
breast feeding - breast milk is iron deficient 
hookworm 
cancer

Question 22

Give some examples of conditions that can cause anaemia of chronic disease

Answer 22

kidney failure, Crohn’s, RA, cancer, heart failure

Question 23

Why does kidney failure lead to anaemia?

Answer 23

the kidney makes erythropoietin and as the kidneys fail, not enough epo is made

Question 24

Give examples of causes of normocytic anaemia

Answer 24

1. acute blood loss - over time through in chronic blood loss, iron deficiency will result
2. anaemia of chronic disease
3. combined haematinic deficiency (B12 and iron deficiency)

Question 25

what is erythropoeisis?

Answer 25

formation of RBCs in the bone marrow

Question 26

what are the causes of macrocytic anaemia?

Answer 26

B12/folate deficiency
Alcohol excess/liver disease
Hypothyroid
HAEMATOLOGICAL

Question 27

What are the haematological causes of macrocytic anaemia?

Answer 27

Antimetabolite therapy - eg chemo
Haemolysis - reticulocytes are bigger than RBCs
Bone marrow failure - congenital or acquired
Bone marrow infiltration eg by cancer; leukaemia/lymphoma

Question 28

How do we investigate anaemia?

Answer 28

Thorough history and examination
FBC +film
Reticulocyte count
U/E’s, LFT’s, TSH
B12, folate, ferritin