intro to haematology & anaemia

Question 1

what are the two main principles for electronically counting cells?

Answer 1

the coulter counter

flow cytometry

Question 2

how does the coulter counter work?

Answer 2

semi-automated by preparing a suitable dilution to count cells in
sample then aspirated into the chamber and a count is produced

Question 3

what is pulse height proportional to?

Answer 3

cell volume

Question 4

how does flow cytometry work?

Answer 4

cells pass through flow cell
laser beam scanned through
if laser hits cell we get light scatter which is recorded on a photo diode
gives white cell differentiation

Question 5

what effect keeps the cells in single file during flow cytometry?

Answer 5

hydrodynamic

Question 6

mean corpuscular volume calculation

Answer 6

haematocrit x 10 / red blood count

Question 7

MCV unit

Answer 7

fL (femto litres)

Question 8

MCV normal range

Answer 8

80-100 fL

Question 9

normocytic meaning

Answer 9

when red cells have a normal MCV

Question 10

macrocytic meaning

Answer 10

when red cells have a MCV of above 100fL

Question 11

microcytic meaning

Answer 11

when red cells have a MCV of below 80 fL

red cells are small

Question 12

mean cell haemoglobin calculation

Answer 12

haemoglobin level / red blood count

Question 13

MCH unit

Answer 13

pg (pico grams)

Question 14

MCH normal range

Answer 14

30 - 35 pg

Question 15

mean cell haemoglobin concentration calculation

Answer 15

haemoglobin level x 100 / haematocrit

Question 16

MCHC unit

Answer 16

g/L (grams per litre)

Question 17

MCHC normal range

Answer 17

300 - 340 g/L

Question 18

normochromic meaning

Answer 18

when erythrocytes contain the normal amount of haemoglobin

MCHC is normal

Question 19

hypochromic meaning

Answer 19

when erythrocytes have a MCHC of below 300 g/L

erythrocytes appear pale

Question 20

hyperchromic meaning

Answer 20

when erythrocytes have a MCHC of above 3401 g/L

Question 21

what % of bone marrow is fat?

Answer 21

50%

Question 22

where does haematopoiesis take place?

Answer 22

in the bone marrow

Question 23

what is haematopoiesis?

Answer 23

blood cell production

Question 24

what stain is used on a bone marrow sample?

Answer 24

May Grunwald-Giemsa stain

Question 25

at what stage are cells at in the bone marrow?

Answer 25

all different stages | eg precursor, immature and mature

Question 26

at what stage are the cells at in peripheral blood?

Answer 26

mature

Question 27

what does the presence of nucleated erythrocytes in peripheral blood suggest?

Answer 27

the bone marrow is stressed | its trying to push out as many erythrocytes as possible regardless of what stage they are at

Question 28

what is a normoblast?

Answer 28

immature erythrocyte

Question 29

stages of red blood cell production

Answer 29

``` pronormoblast early normoblasts intermediate normoblasts late normoblasts reticulocytes red blood cells ```

Question 30

what is a reticulocyte?

Answer 30

an immature red blood cell without a nucleus | has a granular appearance when stained

Question 31

why to erythrocytes require energy?

Answer 31

to maintain cellular shape and haemoglobin structure

Question 32

what are the differences between erythrocytes and other cells?

Answer 32

mature erythrocytes have no nucleus so cant synthesise proteins no mitochondria so do not carry out oxidative metabolism take up glucose by facilitated diffusion

Question 33

how many chains is adult haemoglobin made up of? name them

Answer 33

4 chains in total 2 alpha chains 2 beta-delta-gamma chains

Question 34

what type of ring structure is heme?

Answer 34

planar porphrin

Question 35

what is the primary role of iron?

Answer 35

binding oxygen to haem and myoglobin

Question 36

causes of iron deficiency

Answer 36

``` blood loss increased demand during pregnancy and growth malabsorption poor diet chronic inflammatory diseases malignant diseases ```

Question 37

blood film characteristics when iron deficiency is present?

Answer 37

``` microcytosis hypochromia elliptocytes tear drop poikilocytes rouleaux formation ```

Question 38

what are elliptocytes?

Answer 38

long oval shaped cells

Question 39

what are poikilocytes?

Answer 39

abnormally shaped cells

Question 40

what does rouleaux formation mean?

Answer 40

stacked erythrocytes

Question 41

what is normocytic anaemia?

Answer 41

when haemoglobin and red cell count is low but mean corpuscular volume is in the normal range

Question 42

what are the causes of normocytic anaemia?

Answer 42

renal failure and lack of erythropoietin | acute blood loss from trauma

Question 43

why is vitamin B12 and folic acid needed?

Answer 43

ensures enough DNA is produced from the constituents of the bases allowing successful cell division

Question 44

what does a lack of vitamin B12 and/or folic acid lead to?

Answer 44

reduced and abnormal cell division

Question 45

why are red blood cells affected by B12/folic acid deficiency?

Answer 45

because of their high turnover rate

Question 46

where is vitamin B12 absorbed?

Answer 46

through the intestines

Question 47

what percentage of vitamin B12 is stored in the liver?

Answer 47

80

Question 48

how long does it take for symptoms of vitamin B12 deficiency to develop?

Answer 48

3-4 years

Question 49

what does vitamin B12 have to combine with in order to be absorbed? where is it produced?

Answer 49

intrinsic factor produced by stomach lining

Question 50

how is vitamin B12 transported in blood?

Answer 50

by Transcobalamin II

Question 51

what are common reasons as to why vitamin B12 deficiency occurs?

Answer 51

stomach cant produce enough intrinsic factor intestine cant absorb enough vitamin B12 diet lacks enough food that contains vitamin B12

Question 52

why is vitamin B12 deficiency hard to spot?

Answer 52

symptoms are the same as those for iron deficiency

Question 53

what is pernicious anaemia?

Answer 53

a lack of intrinsic factor

Question 54

how much vitamin B12 is required daily?

Answer 54

1 microgram

Question 55

how much folate is required daily?

Answer 55

100 - 200 micrograms

Question 56

what are the symptoms of folate deficiency?

Answer 56

loss of sensation inability to control muscles depression neural tube defects in fetus

Question 57

why cant folate be stored for a long time in the body?

Answer 57

it is water soluble

Question 58

what causes folate deficiency?

Answer 58

diet lacking in food containing folate lack of absorption excessive urination some types of medicine

Question 59

causes of macrocytic anaemia

Answer 59

vitamin B12 deficiency folate deficiency hypothyroidism liver disease

Question 60

what are the characteristics of a blood film when macrocytic anaemia is present?

Answer 60

``` macrocytes ovalocytes polychromasia tear drop poikilocytes stomatocytes hypersegmented neutrophils ```

Question 61

what are stomatocytes?

Answer 61

red cells with an oblong centre

Question 62

what are hypersegmented neutrophils?

Answer 62

neutrophils with more than 5 lobes

Question 63

what does the presence of hypersegmented neutrophils and megaloblasts in the bone marrow signify?

Answer 63

cell division is disrupted | chromosomes have replicated but the cell membrane has not dissolved and regenerated into daughter cells