Case 11 - Anaemia Flashcards
Development of RBC and the corresponding anaemia film?
Materials needed to make the nucleus - folate, B12
Materials needed to make Hb - iron
The nucleus is made and then extruded from the cell - the high concentration of Hb in the cell determines when this happens
If the nucleus is ready, the cell will undergo divisions
Therefore anything that slows down Hb production > more divisions, so microcytic hypochromic anaemia
Anything that slows down the nuclear development, leads to fewer divisions, so macrocytic normochromic anaemia
The patient may not produce Hb properly in teh first place too - e.g. renal disease
How is iron absorbed?
Ferroportin decreases the amount of hepcidin there is
Hepcidin releases iron from macrophages and enterocytes so there is more for metabolism
Transferrin saturation, high IL-6 concentration (increases in chronic disease) all increase ferroportin
Low transferrin saturation and hypoxia decrease ferroportin
How is B12 absorbed?
Transcobalamin binds to B12 to resist the acidity of the stomach, gets broken apart by pancreatic proteases
Intrinsic factor is able to bind B12
Cubulin receptors in terminal ileum take up complex
How is folate transported?
Folate is stored in RBC with roughly 3 months worth of supply
Dietary folate polyglutamates are converted to monoglutamates
In high folate states they are absorbed through simple diffusion
In low folate states, they are transported by a carrier
Signs and symptoms of anaemia?
Pale Clammy Chest pain Cold hands and feet Headache Dizzy Light-headedness Fatigue Weakness Arhrythmia SOB
What blood tests can be done for anaemia?
FBC - Hb
MCV - size of cells
MCH - tells you conc of Hb ie. hypochromic/normochromic
MCHC - tells you mean Hb conc - increase is an indicator of microspherocytosis
Blood film and microscopy to assess shape of the cells and whether it is a haemolytic anaemia
Inner paler patch should be less than a third of the diameter of the cell
What are causes of normocytic normochromic anaemia?
Blood loss
Anaemia of chronic disease
Anaemia of renal failure (EPO deficiency)
What are symptoms of normocytic normochromic anaemia?
Tachycardia Pale Clammy Loss of consciousness Hypotension
What is the treatment of normocytic normochromic anaemia?
Replace blood with transfusions and clotting factors to prevent coagulopathies - if there’s no response too fluids, cross match and transfuse
What are causes of microcytic hypochromic anaemia?
Thalasseamias Iron deficiency Chronic inflammation (IL-6)
Iron deficiency could be dietary, malabsorption or due to blood loss somewhere in the GIT for example, may also be due to menorrhagia
Important to ask about diet, but rare to get iron deficiency anaemia on the basis of diet, so should question about other blood loss
How can thalassaemias be categorised?
Beta thalassaemia trait (minor) - where only one beta globin is abnormal. Increased HbA2
Beta thalassaemia major - where 2 beta globins are abnormal. No HbA, only HbF
Alpha thalassaemia - anywhere from 1-4 genes affected
What are symptoms of microcytic hypochromic anaemia?
Headache
Brittle nails
Hair loss
Koilinichya
Management of iron deficiency anaemia?
Can do iron transfusions if very severe
Iron supplements are available in tablets and liquid form (100-200mg a day)
Will give constipation, stomach upset and potentially dark stool
Increase vitamin C intake to help absorption
Can take up to 6 months for the iron levels to come back normal
Management of thalassaemia?
Transfusion-based management
Iron chelation gets rid of excess iron
Can have stem cell transplant
Causes of macrocytic normochromic anaemia?
Folate and B12 deficiency
Also alcohol, pregnancy, hypoxia, hypothyroidism
Could be dietary, malabsorption (crohn’s), intrinsic factor deficiency, increased requirement, increased turnover or due to alcohol (folate)
