week 1B

Question 1

what is macrocytosis

Answer 1

enlarged RBCs

Question 2

what is macrocyclic anaemia

Answer 2

anaemia where RBCs are bigger than normal

Question 3

MCV

Answer 3

mean corpuscular volume

Question 4

MCV unit

Answer 4

femtolitres (fl)

Question 5

MCV measures what and why

Answer 5

measures mean RBC volume, tell sis if its macro, normo or micro anaemia

Question 6

what is a normal MCV of a RBC

Answer 6

80-100 fl

Question 7

on blood film how can you tell if there is macrocyclic anaemia

Answer 7

there will be lymphocytes on film, if RBC is bigger than lymphocyte nucleus there is macro. also see paler RBCs

Question 8

in amcrocytic anaemia what might FBC show

Answer 8

low Hb
low RBC
low HCT
high MCV

Question 9

2 true causes of microcytosis

Answer 9

megablastic

non-megaloblastic

Question 10

stages of erythropoiesis (6)

Answer 10

pronormobast > early normoblast > intermediate normoblast > late normoblast > reticlocyte > erythrocyte

Question 11

at what stage of erythropoiesis does the cell begin to enucleate

Answer 11

between late normoblast and reticulocyte

Question 12

at what stage of erythropoiesis do RBC start to appear in blood

Answer 12

reticulocyte

Question 13

what does megaloblastic mean

Answer 13

an abnormally large nucleated RBC precursor with an immature nucleus

Question 14

megaloblastic anaemia is characterised by what

Answer 14

defect in DNA synthesis and nuclear maturation with preservation of RNA and haemoglobin synthesis

Question 15

why are RBCs bigger in megablastic anaemia

Answer 15

cytoplasm develops as normal (get big enough to divide) but nucleus is still immature. CELL FAILS TO BECOME SMALLER

Question 16

macrocytosis id when HCV is >____fl

Answer 16

> 100 fl

Question 17

Causes of megaloblastic anaemia

Answer 17

B12 deficiency
Folate deficiency
drugs
rare inherited shit

Question 18

why do B12 an folate deficiency cause megaloblastic anaemia

Answer 18

enable chemical reactions that provide nucleosides for DNA

Question 19

cycle that uses B12

Answer 19

methionine cycle

Question 20

cycle that uses folate

Answer 20

folate cycle

Question 21

2 important biochemical pathways that interact and use B12 and folate

Answer 21

methionine cycle (B12) 
folate cycle

Question 22

why must stomach be acidic for b12 absorption

Answer 22

removes colbamine (B12) from animal protein

Question 23

what is secreted in stomach that is needed for B12 absorption

Answer 23

intrinsic factor

Question 24

what things can reduce intrinsic factor in stomach

Answer 24

pernicious anaemia
gastric atrophy
gastric bypass

Question 25

B12 absorption pathway

Answer 25

in meat > cleaved from meat by acids > binds haptocorin > moves to duodenum > pancreatic juices cleve off haptocorin . binds intrinsic factor > moves to terminal ileum where cubulin cleaves of intrinsic factor and B12 absorbed

Question 26

things that can affect B12 in duodenum

Answer 26

chronic pancreatitis

Question 27

things that can affect B12 in small bowel

Answer 27

coeliacs, crohns, resection, bacterial over growth

Question 28

folate is converted into

Answer 28

mono glutamate

Question 29

where is folate (monoglutomate) absorbed

Answer 29

jejunum and duodenum

Question 30

sources of B12

Answer 30

animal

Question 31

sources of folate

Answer 31

leafy veg, yeast

Question 32

body stores of B12 last how long

Answer 32

2-4 years

Question 33

body stores of folate last how long

Answer 33

4 months

Question 34

daily requirements of B12

Answer 34

1-3ug/day

Question 35

daily requirements of folate

Answer 35

100ug/day

Question 36

why is inadequate folate intake more likely than B12

Answer 36

lesser stores

Question 37

what can cause malabsorption of folate

Answer 37

coeliacs and crohns

Question 38

features of B12/folate deficiency

Answer 38

anaemia | weight loss, diarrhoea, infertility, sore tongue, jaundice

Question 39

feature of B12 deficiency alone

Answer 39

neurological problems

Question 40

what is pernicious anaemia

Answer 40

autoimmune resulting in destruction of gastric parietal cells

Question 41

what will pernicious anaemia blood film show

Answer 41

- microcytic anemia | - blood film will show hyperhsegmented neutrophils (normally 3-5, so >5) *megaloblastic*

Question 42

what lab tests can you do for pernicious anaemia

Answer 42

- assay B12 and folate (can be wrong) | - check for auto-antibodies against gastric parietal cells) and anti-intrinsic factor

Question 43

how do you treat megaloblastic anaemia

Answer 43

- treat cause - give vit B12 injections (for life in pernicious anaemia) - folic acid tablets (5mg day) - transfusion if life-threatening anaemia

Question 44

dose of folate you give

Answer 44

5mg day orally

Question 45

type of B12 given IV

Answer 45

hydroxycobalamin

Question 46

2 cause categories of macrocytosis are:

Answer 46

genuine or spurious

Question 47

what can cause spurious macrocytosis

Answer 47

1) reticulosis: marrow response to acute bleeding or haemolysis 2) cold-agglutinin disease: RBCs agglutinate, analyser registers this as a single large RBC

Question 48

what things can you measure for anaemia

Answer 48

haemoglobin concentration | haematocrit

Question 49

normal Hb for man

Answer 49

Hb 130g/L

Question 50

normal Hb female

Answer 50

Hb 120g/L

Question 51

normal haematocrit for man

Answer 51

Hct 0.38 - 0.52

Question 52

normal haematocrit for woman

Answer 52

Hct 0.37 - 0.47

Question 53

what cell 'nurses' erythroid precursors

Answer 53

central nursing histiocyte

Question 54

how is Hb measured

Answer 54

lyse RBCs, and measure optical density, measure OD proportional to concentration (beer's law)

Question 55

how do you measure haematocrit

Answer 55

as a proportion of settles blood sample

Question 56

when is Htc and Hb not good measures of anaemia

Answer 56

if rapid blood loss, can lose half volume of blood but sample will still appear normal....until you give fluids that will then dilute down remaining BRCs or if you give fluids which then increase volume and cause dilution

Question 57

what is reticulocytosis

Answer 57

high number of reticulocytes in blood due to large RBc production in response to haemolytic anaemia or blood loss

Question 58

what do kindeys sense to then cause EPO release

Answer 58

reduced oxygen carrying capacity

Question 59

what will reticulocytes have visible in them, what is this called, and how will it change appearance

Answer 59

RNA remnants, called polychromasia, cells will have blue/gray appearance

Question 60

MCH

Answer 60

mean cell hemoglobin concentration

Question 61

normal HCV values

Answer 61

80 - 96