Haematology

Question 1

Blood films

Answer 1

Provides information on:

• platelet counts
• white cell counts
• red cell counts
• blood cell morphology
• sources of error

Question 2

Normal erythrocyte morphology

Answer 2

Biconcave disc
Anucleated
Central area of pallor
Stain a pink/red colour - acidophilic

Question 3

Neutrophil morphology

Answer 3

Multilobed nucleus - 3-5 lobes
Stains a blue/red colour - neutral
Granules in cytoplasm

Question 4

Lymphocyte morphology

Answer 4

Large nucleus with very little cytoplasm

Stains a blue/purple colour - basophilic

Question 5

Monocyte morphology

Answer 5

Large indented nucleus with minimal cytoplasm
Stains a blue/purple colour - basophilic
May contain many ‘holes’ where vacuoles are present

Question 6

Eosinophil morphology

Answer 6

Lobed nucleus - 2 lobes connected by a band
Nucleus stains blue/purple colour - basophilic
Cytoplasm stains red/pink colour - acidophilic
Granules in cytoplasm

Question 7

Basophil morphology

Answer 7

Extremely granulated
Nucleus appears non-existant
Very rarely seen as so uncommon
Stains a blue/purple colour - basophilic

Question 8

Microcytic

Answer 8

Small red blood cell size

Question 9

Normocytic

Answer 9

Normal red blood cell size

Question 10

Macrocytic

Answer 10

Large red blood cell size

Question 11

Anisocytosis

Answer 11

Red blood cells of unequal size

Question 12

Poikilocytosis

Answer 12

Abnormal shaped red blood cells

Question 13

Hypochromia

Answer 13

Less colour than usual under staining - less haemoglobin

Question 14

Hyperchromia

Answer 14

More colour than usual under staining - more haemoglobin

Question 15

Polychromasia

Answer 15

Abnormal coloured red blood cells - unequal haemoglobin content

Question 16

Manual cell counting

Answer 16

For red blood cells - count 5 of 25 smaller middle squares

For white blood cells - count 4 larger corner squares

Question 17

Manual cell counting calculations

Answer 17

(Number of cells x dilution x 10^6) / V
For red blood cells V = 0.02, D = 201
For white blood cells V = 0.4, D = 20

Question 18

Absolute white blood cell differential count

Answer 18

(Number of each white blood cell x total WCC) / number of cells counted typically 100

Question 19

Blood grouping

Answer 19

Important in blood transfusions to ensure there is no adverse reaction

Question 20

Forward blood grouping

Answer 20

Add antisera A and B to an unknown group sample.
The sample will agglutinate if the red cell has the receptor for the antibody present in the antisera.
A blood react with A, not B antisera
B blood react with B, not A antisera
AB blood react with both antisera
O blood react with neither antisera

Question 21

Reverse blood grouping

Answer 21

Add known group red cells to unknown group plasma.
The red cells will agglutinate if the plasma is of a different group.
A plasma react with B blood
B plasma react with A blood
AB plasma react with no blood
O plasma react with A and B blood

Question 22

Anaemia

Answer 22

Low haemoglobin concentration
Microcytic anaemia - nutritional iron deficiencies
Normocytic anaemia - blood loss
Macrocytic anaemia - nutritional B12 and folic acid deficiencies

Question 23

Polycythemia

Answer 23

Increase haemoglobin due to increased red blood cell production or decreased water
Dehydration, hypoxia (smoking, high altitude)

Question 24

Target or bell-shaped red blood cells

Answer 24

Liver disease due to alcoholism

Question 25

Echinocytes

Answer 25

Burr-shaped cells with small projects | Acute kidney failure

Question 26

Acanthocytes

Answer 26

Red blood cells with long spiky projections | Acute kidney failure

Question 27

Sickle cells

Answer 27

Sickle-shaped cells | Sickle cell disease

Question 28

Ovalocytes

Answer 28

Oval shaped cells | Mutation in red cell membrane - no clinical problems

Question 29

Spherocytes

Answer 29

Sphere shaped cells | Genetic causes

Question 30

Red cell count RCC

Answer 30

Number of red blood cells x10^12 per litre Low RCC - anaemia - blood loss, nutrient deficiency, infection High RCC - erythrocytosis - hypoxia, dehydration, illicit EPO use

Question 31

Packed cell volume PCV and haematocrit HCV

Answer 31

The proportion of blood that is erythrocytes Expressed as L/L or % Direct measurement = blood cell height / total blood height Calculated measurement HCV = MCV x RCC

Question 32

Mean cell haemoglobin MCH

Answer 32

Average mass of haemoglobin in each red blood cell Expressed as picograms - pg (10^-12 g) Calculated measurement = [Hb] / RCC

Question 33

White blood cell terminology

Answer 33

``` Leukocyte increase - leukocytosis Leukocyte decrease - leukopaenia Lymphocyte increase - lymphocytosis Lymphocyte decrease - lymphopaenia Neutrophil increase - neutrophilia Neutrophil decrease - neutropaenia Monocyte increase - monocytosis Eosinophil increase - eosinophilia Basophil increase - basophilia ```