macrocytosis andmacrocytic anaemia

Question 1

macrocytosis?

Answer 1

big cells, increase in number of cells

Question 2

macrocytic anaemia

Answer 2

anaemia in which red cells have a larger than normal volume

Question 3

units of MCV?

Answer 3

femtolitres

Question 4

normal MCV?

Answer 4

80-100

over 100 is macrocytic

Question 5

blast =

Answer 5

with a nucleus

Question 6

what is a megalosbast?

Answer 6

abnormally large nucleated red cell precurosor with an immature nucleus

Question 7

megaloblastic anaemias are characterised by predominent defects in ?

Answer 7

DNA synthesis and nuclear maturation, with relative preservation of RNA and haemoglobin synthesis

Question 8

preservation of ?

Answer 8

RNA and haemoglobin synthesis

Question 9

while cytoplasm has developed and become mature (big enough to divide), the nucleus is still immature and lagging behind

Answer 9

leads to bigger than normal red precursor

Question 10

cell can sense it has enough haemoglobin and doesnt need to divide anymore

Answer 10

end result = microcytic cells

Question 11

larger cell in megaloblastic anarmia due to?

Answer 11

a failure to become smaller, not an increase in cell size

Question 12

causes of megaloblastic anaemia

Answer 12

b12 deficiency
folate deficiency
others - drugs or rare inherited anomalies

Question 13

what are b12 and folate essential co factors for?

Answer 13

nuclear maturation

Question 14

what do they enable?

Answer 14

chemical reactions that provide enough nucleosides for DNA SYNTHESIS

Question 15

2 cycles ?

Answer 15

methionine and folate cycle

Question 16

b12 and folate biochemical reactions are interlinked .

Answer 16

what does the methionine cycle produce?

Question 17

s-adenosyl methionine

Answer 17

y

Question 18

what is s-adenosyl methionine?

Answer 18

a methyl donor to DNA and folate intermediates

Question 19

folate cycle important for nucleoside synthesis

Answer 19

eg uridine to thymidine conversion

Question 20

what is b12 bound to in the stomach ?

Answer 20

haptocorrin

Question 21

ditches haptocorrin and binds with ?

Answer 21

IF

Question 22

absorbed across which receptors?

Answer 22

cubulin

Question 23

where is b12 absorbed?

Answer 23

ileum

Question 24

dietary folates converted into?

Answer 24

monoglutamate

Question 25

where is folate absorbed?

Answer 25

jejunum

Question 26

where do you get vitamin b12 from?

Answer 26

animal

Question 27

folate?

Answer 27

leafy geren veg - destroyed by cooking

Question 28

how long does body store vitamin b12?

Answer 28

2-4 years

Question 29

folate?

Answer 29

4 months

Question 30

B12 ilium

Answer 30

bilium

Question 31

Folate at Duodenum and Jejunm

Answer 31

.

Question 32

causes of folate deficiency?

Answer 32

dietary causes more likely than b12 due to lesser stores. malabsorption (coeliac, crohns)

Question 33

when can you get excess utilisation of folate?

Answer 33

haemolysis, exfoliating dermatitis, pregnancy, malignancy

Question 34

which type of drugs cause folate deficiency?

Answer 34

anti convulsants

Question 35

clinical features of B12 and folate deficiency?

Answer 35

symptoms/signs of anaemia, weight loss, diarrhoea, sore tongue, jaundice

Question 36

if you have vitamin b 12 problems only, can get neurologica problems i.e. neuropathy, dementia, psychiatric manifestations

Answer 36

y

Question 37

autoimmune condition resulting in destruction of gastric parietal cells?

Answer 37

pernicious anaemia

Question 38

associated with atrophic gastritis and personal or family history of other autoimmune disorders

Answer 38

eg hypothyroidism, addisons

Question 39

perniciooud anaemia also known as ?

Answer 39

b12 defiency anaemia

Question 40

why do you get a shortage of b12?

Answer 40

autoimmune attack against gastric parietal cells, which produce intrinsic factor

Question 41

what would blood film show?

Answer 41

macrovalocytes and hypersegmented neutrophils (usually 3-5 nuclear segments)

Question 42

pancytopaenia in some patients

Answer 42

y

Question 43

diagnosis...?

Answer 43

anti GPC (gastric parietal cell) and anti intrinsic factor (anti IF)

Question 44

which one is sensitive and non specific?

Answer 44

ant GPC

Question 45

which one is specific and non sensitive?

Answer 45

anti IF

Question 46

can also do?

Answer 46

assay b12 and folate levels in serum

Question 47

treatment of megaloblastic anaemia?

Answer 47

treat the cause | folic acid tablets orally

Question 48

treatment for p anemia?

Answer 48

b12 injections for life

Question 49

causes of non megaloblastic macrocytosis? (big cells, increased number)

Answer 49

LAHM - liver disease, alcohol, hypothyroidism, marrow failuer

Question 50

spurrious macrocytosis

Answer 50

reticulocytes bigger than mature red blood cells

Question 51

what does reticulocytosis indicate?

Answer 51

marrow response to loss of red cells either through acute bleeding or haemolysis

Question 52

in cold agglutinated disease, what happens?

Answer 52

analyser gets confused as clumps of agglutinated red cells go through and are registered as 1 big cell

Question 53

why can patients with pernicious anaemia appear mildly jaundiced?

Answer 53

due to intramedullary haemolysis

Question 54

why do you get jaundice in pernicious anaemia?

Answer 54

defective red cells broken down. ham converted to bilirubin

Question 55

can get pancytopenia due to b12 folate deficiency

Answer 55

nuclear maturation defects can affect all lineages