Iron Deficiency Anaemia Flashcards
Anaemia is the a condition in which the body does not have enough healthy erythrocytes, which are immature RBCs. To stimulate proerythroblast in the bone marrow, which organ secretes most of the erythropoietin in the body?
1 - heart
2 - bone
3 - liver
4 - kidney
4 - kidney
RBCs contain a protein called haemoglobin. Each haemoglobin contains 4 heme molecules. What is contained at the centre of the heme molecules?
1 - Ca2+
2 - Mg2+
3 - iron
4 - vitamin B1
3 - iron
- important for binding to O2
- each haemoglobin can bind 4 molecules of O2
The state of iron when it binds with and without O2 changes. Match the iron state when O2 is and is not bound?
- Fe3+
- Fe2+
- bound O2 = Fe3+
- unbound O2 = Fe2+
How many molecules of oxygen can each haemoglobin molecule bind with?
1 - 8
2 - 6
3 - 4
4 - 2
3 - 4
Our diets contain 2 forms of iron,
- heme iron (meats) = Fe2+ iron is already bound to haemoglobin
- non-heme iron (vegetables) = Fe3+ as not bound to haemoglobin
When we eat and the foods get digested, is all iron converted into Fe2+ or Fe3+?
- Fe2+
Our diets contain 2 forms of iron,
- heme iron (meats) = Fe2+ iron is already bound to haemoglobin
- non-heme iron (vegetables) = Fe3+ as not bound to haemoglobin
Once digested, all iron is converted into Fe2+ in the duodenal cells. Iron then binds to what?
1 - transferrin
2 - ferritin
3 - feroportin
4 - hepcidin
2 - ferritin
- if needed Fe2+ iron is released into the blood
- hepastin converts Fe2+ into Fe3+ in the blood
Once release from ferritin into the blood, Fe2+ iron is converted into Fe3+ by hephaestin. The Fe3+ then binds to what iron transporter to be transported to tissues in the body?
1 - transferrin
2 - ferritin
3 - feroportin
4 - hepcidin
1 - transferrin
- ferritin is present in tissues to store the Fe3+
There are lots of causes of anaemia, which is the most common?
1 - B12 deficiency
2 - anaemia of chronic disease
3 - iron deficiency anaemia
4 - sickle cell anaemia
3 - iron deficiency anaemia
Mean corpuscular volume (MCV) is a test to measures the average size of RBCs. This can be:
- microcytic = small (<75fl)
- macrocytic = large (>96fl)
- normacytic = 80-96fL
Which of the above does iron deficiency anaemia lead to?
- microcytic = small (<75fl)
Which of the following are causes of iron deficiency anaemia?
1 - low iron intake
2 - reduced iron absorption
3 - iron loss
4 - increased iron demand
5 - all of the above
5 - all of the above
- low iron intake is the most common cause
Which of the following can lead to low iron intake, which is the most common cause of iron deficiency anaemia?
1 - vegetarian diets
2 - GIT disorders (coeliac diseases, IBD)
3 - reduced gastric acid secretions
4 - pregnancy
5 - menorrhagia
6 - malignancy
7 - urological
8 - helicobacteria pylori infection
9 - all of the above
9 - all of the above
- helicobacteria pylori = eats irons before we can absorb it
- vegetarian diets = FE3+ is harder to digest and absorb
- urological = CKD where we can lose blood or malignancy
There are 3 main causes of microcytic anaemia. Which of the following is NOT one of these?
1 - iron deficiency
2 - Haemoglobinopathies – thalassaemia, sickle cell
3 - Sideroblastic anaemia
4 - B12 deficiency
4 - B12 deficiency
- B12 deficiency would cause megablastic anaemia
Sideroblastic anaemia is one of the 3 causes of microcytic anaemia. What is Sideroblastic anaemia?
1 - low levels of iron in RBCs
2 - RBCs with altered globulins
3 - high iron levels in RBCs
4 - all of the above
3 - high iron levels in RBCs
- iron cannot be incorporated into heme or carry O2
We typically lose around 1mg of iron everyday. Why is this?
1 - RBCs undergoing programmed cell death in spleen
2 - iron lost in sweat
3 - iron excreted into stool
4 - all of the above
4 - all of the above
- but we can eat iron to account for the lost iron
Why does iron deficiency anaemia lead to microcytic anaemia (<75fl, normal is 79-96)?
1 - low erythropoietin
2 - low haemoglobin
3 - high haemoglobin
4 - high ferritin
2 - low haemoglobin
- normal haemoglobin:
males = 130-180
female = 115-165
- not enough haemoglobin means bone marrow jus makes small RBCs
- microcytic RBCs are pale as well called hypochromic RBCs
One of the key signs of iron deficiency anaemia is koilonychia, why does iron deficiency anaemia cause koilonychia?
1 - microcytic RBCs impairs nail growth
2 - microcytic RBCs breakdown reduces keratin levels
3 - low iron causes defects in mitochondrial enzymes
4 - low iron reduces epithelial cell number
3 - low iron causes defects in mitochondrial enzymes
- affects ATP levels and fast growing tissue, such as epithelial cells
- hence nails and hair are affected
Which of the following is NOT a typical clinical sign of iron deficiency anaemia?
1 - icterus
2 - koilonychia
3 - hair loss
4 - glossitis
5 - oesophageal webs
1 - icterus
- medical term for jaundice
- plummer vinson syndrome includes glossitis and oesophageal webs
When trying to diagnose iron deficiency anaemia, all of the following can typically be seen, EXCEPT which one?
1 - low Hb
2 - low MCV
3 - high ferritin
4 - low serum iron
5 - high total iron binding capacity (unbound transferritin)
6 - variety of RBC sizes
3 - high ferritin
- ferritin is typically low because it is only released from cells when iron is present or needed. So no iron to release means ferritin will be low
