anaemia

Question 1

The main stimulus for the production of RBCs in bone marrow is reduced delivery of O2 to the tissues. Which organ senses the reduced O2 level and stimulates the production of new RBCs?

Answer 1

kidneys

Question 2

Each RBC contains 250 million Hb molecules. Therefore, how many O2 molecules can each RBC carry?

Answer 2

haem molecule carry 4 O2 so 1 billion

Question 3

In addition to O2, what three other gases can Hb carry in the blood?

Answer 3

carbon dioxide
nitric oxide
carbon monoxide

Question 4

How long do RBCs live and where do they go to die?

Answer 4

RBC circulate in the blood fro about 120days before being recycled by the spleen

Question 5

if going off these values what would the RBC look like
Hb 100
• MCV 82
• MCHC 330

MCV 80-99
MCHC-320-360
normal values

Answer 5

Normocytic normochormic

Question 6

if going off these values what would the RBC look like
Hb 100
• MCV 104
• MCHC 330

Answer 6

Macrocytic normochromic anaemia

Question 7

if going off these values what would the RBC look like
Hb 100
• MCV 72
• MCHC 260

Answer 7

microcytic hypochromic anaemia

Question 8

where is iron mainly absorbed in the small intestine

Answer 8

Enterocytes of duodenum and jejunum

Question 9

Two forms of heme for absoprtion.
Which of the following is/are the non-heme iron?

Fe2+
Fe3+
Ferric ion
Ferrous ion

Answer 9

Fe3+= Ferric– non-heme
- Less well absorbed

Fe2+= Ferrous = binds to O2– heme
- Major form of iron more easily absorbed

Question 10

Fe2+ or Fe3+ gets transported across the enterocyte brush boarder directly?

Answer 10

Fe^2+

Fe2+ soluble while Fe3+ isn’t

• Fe3+= FAT; Fe2+= slim
  🡪 needs to get slimmer to squeeze through 🡪 Fe2+ is the one

Ferroreductase= duodenal cytochrome B is the enzyme that is required for the conversion

Question 11

Iron is bound to what/ stored as what in the enterocytes? And what state is the iron in?

Answer 11

Ferritin; Fe3+

30% stored as ferritin in liver, bone marrow and spleen.
Iron study: Serum ferritin= best diagnostic test for iron deficinecy anaemia= measure of iron stores = ferritin= APP 🡪 changes in infection

Monomers of the ferritin molecule have ferroxidase activity (Fe3+ ↔ Fe2+) which allows the mobilization of Fe2+ ions out of the ferrihydrite mineral lattice structure, enabling its subsequent efflux out of the enterocyte via ferroportin, and into circulation across the basolateral membrane of the enterocyte.

Question 12

What does iron bind to within circulation?

Answer 12

transferrin

Reason: Fe3+ is toxic as it is involved in the fenton reaction which generates free radical

Iron mobilisation to the circulation relies on transport protein transferrin
A beta 1 globulin . Transferrin of siderophilin

Iron travels to bone marrow to produce RBC
Or to Liver for storage

Transferrin as an indicator for TIBC- transferrin iron binding capacity -> iron study

Question 13

chose the right words

When iron levels are excessively high, hepcidin levels increase/decrease.
Hepcidin binds to the transferrin/ ferroportin on basolateral surface of gut enterocytes and macrophages in spleen, stopping iron transport out of the cells.

Answer 13

increase and ferroportin

Regulators of iron: hepcidin levels.

High levels of iron, inflammatory cytokines, and oxygen lead to increased levels of the peptide hormone hepcidin.

Hepcidin binds ferroportin, resulting in its internalization and degradation and effectively shunting cellular iron into ferritin stores and preventing its absorption into the blood.

Iron recycling within the macrophages in spleen when rbc reach the end of their lifespan 🡪 iron is realeased from heme

Thereby, hepcidin also potentiates the excretion of iron through the sloughing of enterocytes (and their ferritin stores) into the feces and out of the body.

Clinical relevance:
- EPO reduction 🡪 Increased hepcidin activity is partially responsible for reduced iron availability seen in anemia of chronic inflammation, such as kidney failure.[10]

Question 14

How is iron lost from the body?

Answer 14

Sloughing of enterocytes
Faeces
Menstruation

Question 15

if HB of 66
MCV of 58.6
MCHC of 230
what anaemia

Answer 15

severe microcytic hypothermic anaemia - iron deficiency anaemia

ferritin would confirm this

Question 16

if HB was 70
MCV - 105
MCHC was 315
what anaemia

Answer 16

microcytic normochromic anaemia

So B12 or folate deficiency anaemia

If microcytic – Probably iron deficiency commonest
(check ferritin)

If macrocytic – B12/folate commonest
(check B12 and Folate levels)

Question 17

RBC fact slide

Answer 17

Major function:
To transport haemoglobin (Hb),which carries O2 from the lungs to the tissues
Also:
Contain carbonic anhydrase, which speeds up the reversible reaction between CO2 and H2O, to allow the water in the blood to carry large amounts of CO2, in the form of bicarbonate (HCO3), from the tissues to the lungs

Due to the Hb they contain, RBCs are also responsible for most of the acid-base buffering power of the blood

Question 18

Haematocrit (HCT) or Packed Cell Volume represents the percentage of RBCs in the total blood volume. What is the normal value of haematocrit ?

Answer 18

36-49%

Question 19

Which of the following cells within gastric pits release intrinsic factor?

Chief cells
Parietal cells
D cells
G cells

Answer 19

Chief cells – release pepsinogen (a zymogen = inactive precursor of an enzyme; most digestive enzymes are released as zymogens and then activated within the GI tract lumen by proteolytic cleavage by other enzymes or, in the case of pepsin, by HCl-mediate hydrolysis.

Parietal cells - HCl and Intrinsic Factor

D cells – release somatostatin hormone, a negative regulator of gastric acid release and gastric motility.

G cells – release gastrin hormone, a promoter of gastric acid release and gastric motility.

Question 20

3 main groups of anaemias

Answer 20

Anaemia caused by blood loss
Heavy menstruation
Gastrointestinal conditions like ulcers or haemorrhoids and cancers.
Anaemia caused by decreased or faulty red blood cell production
Bone marrow and stem cell problems
Iron deficiency anaemia
Sickle cell anaemia
Anaemia caused by destruction of red blood cells
Aplastic anaemia
Lead poisoning

Question 21

what would be the findings in the blood test for iron deficiency anaemia

Answer 21

Hb normal at start then fall 
MCV( average size) decrease 
MCHC( Hb in RBC decrease) 
Increased variation in the size of RBC (RDW) 
Low ferritin levels expected

Question 22

To confirm that someone has Iron deficiency anaemia:
A blood film may show RBC that are smaller and paler then normal
Serum Iron (Iron level in blood) is usually decreased
Total Iron binding capacity will be increased (more proteins available to carry Iron)
Transferrin saturation index will be low
Ferritin levels will be low (key one)
(unusual) a marrow aspirate test
To confirm that someone has anaemia due to chronic disease: what would you do

Answer 22

Reticulocyte count
Tests for inflammation (ESR or CRP)
Kidney function tests such as serum creatinine
Erythropoietin

Question 23

How would a blood test look for Vitamin B deficiencies

Answer 23

low Hb
High MCV
abnormally larger or and abnormally shaped RBC

Question 24

Tests for haemoglobin variants 
DNA analysis (not routinely done)
G6PD enzyme test 
Osmotic fragility test 
Test for autoantibodies 
Reticulocyte count 

confirmation of what anaemia

Answer 24

Haemolytic anaemia:

Question 25

Vitamin B12 levels will be low in B12 deficiency
Folic acid levels may be low
Mehylmalonic acid may be high with vitamin B deficiency
Homocysteine may be high with either folate or vitamin B deficiency
Reticulocyte count is usually low
Antibodies to intrinsic factor or parietal cell antibodies may be present in pernicious anaemia.
Bone marrow aspiration may be performed

confirmation of what anaemia

Answer 25

Vit B 12 déficiences

Question 26

normal folate range

Answer 26

> 5.4ng/ml

Question 27

iron deficiency anaemia is defined as what

Answer 27

low ferritin <30micrograms/litre , low iron and High total iron binding capacity , high transferring and low iron saturation

Question 28

why should vitamin C be given in anaemia

Answer 28

vitamin c helps the body absorb iron