Anaemia

Question 1

what is anaemia

Answer 1

reduced total red cell mass

Question 2

is red cell mass easy to measure in routine practice

Answer 2

no

Question 3

how is anaemia tested for

Answer 3

haematocrit and haemoglobin

Question 4

where does red cell production take place

Answer 4

in the bone marrow

Question 5

how would you recognise this

Answer 5

several erythroid precurosrs cluster around a central ‘nursing’ histiocyte

Question 6

how do you measure haemoglobin concentration using a spectrophotometric method

Answer 6

burst-lyse the red cells to creat Hb solution
stabilise the Hb molecues (cyan-met Hb)
measure the optical density (OD) at 540nm
OD proportional to the concentration (Beer’s law)
Hb concentration calculated against known reference standard cyan-met Hb concentration solution

Question 7

ow is haematocrit measure

Answer 7

ratio(or %) of the whole blood that is red cells if the sample was left to settle
modern machines calculate this by adding the calculated volume of the red cells it counts

Question 8

when is Hb and haematocrit not a good measure

Answer 8

when there is acute blood loss and haemodilution occurs

Question 9

what is the response to anaemia

Answer 9

increase red cell production-reticulocytosis

Question 10

describe the appearance of retiuclocytes

Answer 10

larger than average red cells
still have remnants of RNA
stain purple/deeper red as a consequence
blood film appears polychromatic

Question 11

what are the measured red cell indicies

Answer 11

haemoglobin concentration
number of red cells (concentration)
size of red cells (mean cell volume)

Question 12

what are the calculated red cell indicies

Answer 12

haematocrit
mean cell haemoglobin
mean cell haemoglobin concentration

Question 13

how is anaemia classified based on pathophysiology

Answer 13

decreased production( low reticulocytes) or increased loss or destruction of red cells (high reticulocyte count)

Question 14

what are the cuases of low reticulocyte count

Answer 14

hypoproliferative-reduced amount of Erythropoeisis

maturation abnormality-erythropoiesis present but ineffective

Question 15

what is high reticulocyte caused by

Answer 15

bleeding, haemolysis

Question 16

what is a practical classification of anaemia based on

Answer 16

cell size and haemoglobin content

Question 17

what is MCV a useful tool for

Answer 17

distinguishing between cytoplasmic and nuclear defects

Question 18

if MCV low this means

Answer 18

microcytic-consider problems with haemoglobinisation

Question 19

if MCV high

Answer 19

macrocytic-consider problems with maturation

Question 20

where does haemoglobin synthesis occur

Answer 20

in cytoplasm

Question 21

what does defects in haemoglobin synthesis cuase

Answer 21

small cells

Question 22

describe microcytic anaemias

Answer 22

small red ells with a low hb content
hypochromatic and microcytic
hb synthesised in cytoplasm

Question 23

to make Hb you need

Answer 23

globins

haem-porphyrin ring and iron

Question 24

what are the causes of hypochromatic microcytic anaemias

Answer 24

haem deficiency-lack of iron for erythropoiesis-iron deficiency (low body iron), some cases of anamia of chronic disease (normal body iron but lack of available iron(
problems of porphyrin synthesis but this is vvv rare
globin deficiency-thalaslassameia

Question 25

when fully saturated 1g hb will bind how much o2

Answer 25

1.34ml O2