Anaemia Flashcards
What is anaemia
A reduction in the haemoglobin concentration (Hb) in the circulating blood below what is normal for a healthy person of the same age and gender as the individual (no absolute cut off)
What are the consequences of low Hb and what presentations are caused?
Low Hb= reduced oxygen around the body
1. Eyes:
- Yellowing
2. Skin:
- Paleness
- Coldness
- Yellowing
3. Resp:
- Shortness of breath
4. Muscular:
- Weakness
5. Intestinal:
- Changed stool colour
6. Central:
- fatigue
- Dizziness
- Fainting
7. Blood vessels:
- Low blood pressure
8. Heart:
- Palpitations
- Rapid heart rate
- Chest pain
- Angina
- Heart attack
9. Spleen:
- Enlargement
What is a blood film?
a sample of blood that’s spread on a glass slide which is treated with a special stain:
allows the evaluation of white blood cells (WBCs, leucocytes), red blood cells (RBCs, erythrocytes), and platelets (thrombocytes).
What are the 3 types of anaemia?
- Microcytic
- Macrocytic
- Normocytic
What is the mechanism of microcytic anaemia?
“Reduced haemoglobin synthesis”- Red blood cells do not grow sufficiently
What is the mechanism of macrocytic anaemia?
“Abnormal haemopoesis” (production of red blood cells):
- Reticulocytes (“baby RBCs”) are large
- Have not lost their nucleus yet
- Abnormal haemopoeisis= RBCs stay in their early stages (reduced development)
What is the mechanism of normocytic anaemia?
The red blood cells are made normally (structurally), but you have fewer number of RBCs than normal:
- RBC pooling in spleen (RBCs are being destroyed)
- Insufficient haemopoesis (not making enough no. of RBCs)
- Acute blood loss (lose the normally- structured RBCs)
What are the causes of microcytic anaemia?
- Iron loss
- Anaemia of chronic disease
- Insufficient intake
- Thalassaemia
How does iron lose lead to microcytic anaemia?
reduced raw material needed to make Hb
How does “anaemia of chronic kidney disease” lead to microcytic anaemia?
You’re eating enough iron but no taking enough to the cells (due to inflammation from the CKD); not enough iron is being used to make Hb
What is meant by “insufficient intake” leading to microcytic anaemia?
Not eating enough iron
How does thalassaemia lead to microcytic anaemia?
Mutation in the gene needed to make Hb
What are the causes of Macrocytic anaemia?
- B12/ folate deficiency (megaloblastic anaemia)
- Liver disease
- Ethanol toxicity
- Haemolytic anaemia (mild, with reticulocytosis)
How does B12/ folate deficiency lead to macrocytic anaemia?
- B12/ folate are needed for DNA production;
- When there is not enough, cells that are “not ready” get ‘kicked out’ (released into the bloodstream)
- Larger than usual (still have their nucleus- are underdeveloped)
How does Liver disease lead to macrocytic anaemia?
- Reduced absorption of vitamins needed to make RBCs
How does ethanol toxicity lead to macrocytic anaemia?
Affects the liver- reduced absorption of material/ vitamins needed for RBC production
How does haemolytic anaemia lead to macrocytic anaemia?
Haemolytic anaemia= “condition that occurs when your red blood cells are destroyed faster than they can be replaced”
You break down RBCs so much, and make so many new ones that you end up with many reticulocytes (again are much larger- underdeveloped- intake nucleus)
What are the causes of normocytic anemia?
GI bleed/ tauma
Chemotherapy
Leukaemia
Sickle cell anaemia
How do GI bleeds/ trauma cause normocytic anaemia?
Increase RBC lose
How can chemotherapy and leukaemia cause normocytic anaemia?
Both can damage the bone marrow (site of hematopoiesis)- in some leakeumia cases, there is no longer production of RBCs, just cancer cells
How can sickle cell anaemia cause normocytic anaemia?
Blood cells are normal when they’re not sickled- you just destroy the RBCs much more rapidly beacuse of the sickling process & pooling
What is haemolysis?
The increased destruction of red blood cells (reduced red cell survival)
What are haemolytic anaemias?
A group of anaemias in which red cell lifespan is reduced (i.e. haemolysis that leads to a reduction in Hb)- your red blood cells are destroyed faster than they can be replaced
What is a complication of haemolytic anaemia?
Haemolytic anaemia increases the levels of bilirubin in the body and can cause jaundice