Anaemia Flashcards
What is it?
Low levels of Hb and/or RBC
How can pregnancy cause anaemia?
Due to increased plasma volume
What 3 symptoms will they complain of?
SOB
Fatigue
Angina - if there is pre-existing coronary disease.
It depends on the cause though!!
Symptoms:
Why do they get faintness?
Why do they get palpitations?
Why do they get tinnitus?
Why is it important to think about anorexia?
There aren’t enough red blood cells to deliver oxygen to the brain.
The heart has to work harder to pump oxygen around the body
If you are anaemic, there is an increased blood flow in the jugular vein as the heart works harder to pump blood between your heart and your brain. To do this, the blood has to pass through your middle ear, resulting in the ringing or other noises.
It may be a direct cause of the anaemia,
Signs - may be absent even in severe anaemia:
What signs are looked for? - 2
Why do they get murmurs?
Severe anaemia:
- What happens to the heart due to increased workload?
- What will occur eventually?
Flow murmurs (ejection-systolic loudest over apex)
Pallor - pale conjunctiva
Tachycardia
An innocent murmur can occur when blood flows more rapidly than normal through the heart.
Cardiac enlargement:
When a section of the heart muscle dies, your heart has to pump harder to get adequate blood to the rest of your body, causing it to enlarge.
Heart failure
Types of anaemia:
What is the first thing that needs to be looked at in the FBC which will initially guide diagnosis?
Looking at MCV - mean corpuscular volume
Low MCV (microcytic anaemia):
What deficiency causes this?
What blood disorder will cause the MCV to be too low for the Hb levels?
Sideroblastic anaemia is another cause:
- What is it?
- What apprearance do the nuclei of the RBC have?
- What type of poisoning could cause this?
Iron-deficiency
Thalassaemia - the name for a group of inherited conditions that affect a substance in the blood called haemoglobin. People with thalassaemia produce either no or too little haemoglobin, which is used by red blood cells to carry oxygen around the body.
The sideroblastic anemias are a group of blood disorders in which the body has enough iron but is unable to use it to make hemoglobin, which carries oxygen in the blood. As a result, iron accumulates in the mitochondria of red blood cells, giving a ringed appearance to the nucleus (ringed sideroblast).
Lead poisoning
Normal MCV (normocytic anaemia):
Anaemia of chronic disease. What is increased in chronic disease?
Increased RBC loss:
- What would cause this?
- What type of anaemia could cause this?
- What organ, if overworking, will cause this?
Ferritin as iron stores are increased in chronic disease and ferritin is an acute phase reactant.
Acute blood loss (post-haemorrhagic anaemia, only becomes apparent after fluid resus)
Haemolytic anaemia
Hypersplenism (could be due to portal hypertension leading splenomegaly)
Normal MCV (normocytic anaemia):
Decreased RBC production:
- What produces RBC?
- Aplastic anaemia is a cause. What is it?
- Myelodysplastic syndrome is a cause, What is it?
- How does renal failure lead to this?
- What thyroid disease could also cause anaemia?
- What else do you need to be thinking about?
Haemodilution:
- What is a major cause in women?
CHRONIC INFLAMMATION LEADS TO ANAEMIA AS IT USES UP IRON STORES
Bone - therefore failure will lead to normocytic anaemia
Aplastic anaemia is a serious condition affecting the blood, where the bone marrow and stem cells do not produce enough blood cells. It is also called bone marrow failure and can happen suddenly (acute) or develop over a period of time (chronic).
Myelodysplastic syndromes (MDS) are a group of cancers in which immature blood cells in the bone marrow do not mature, so do not become healthy blood cells. Early on, no symptoms typically are seen. Later, symptoms may include feeling tired, shortness of breath, easy bleeding, or frequent infections.
When the kidneys are diseased or damaged, they do not make enough EPO. As a result, the bone marrow makes fewer red blood cells, causing anaemia.
Anaemia in hypothyroidism might result from bone marrow depression, decreased erythropoietin production, comorbid diseases, or concomitant iron, vitamin B12, or folate deficiency. Altered iron metabolism and oxidative stress may contribute to anaemia in hyperthyroidism.
Pregnancy due to increased blood volume
High MCV (macrocytic anaemia):
2 types - define the following:
- normoblastic anaemia
- megaloblastic anaemia
Nonmegaloblastic macrocytic anaemias are those in which no impairment of DNA synthesis occurs. Included in this category are disorders associated with increased membrane surface area, accelerated erythropoiesis, alcoholism, and chronic obstructive pulmonary disease (COPD).
Megaloblastic anaemia is characterized by red blood cells that are larger than normal. There also aren’t enough of them.
High MCV (macrocytic anaemia) - Normoblastic:
How does alcoholic liver disease cause this?
The above usually causes macrocytosis. What is the difference between macrocytosis and macrocytic anaemia?
Anaemia in alcoholic liver disease is also associated with a direct toxic effect of alcohol on the bone marrow, causing reversible suppression of hematopoiesis and subsequently anaemia with impaired platelet production and function.
Macrocytosis means that the red blood cells are larger than normal. Macrocytic anaemia occurs when there is also a fall in haemoglobin levels in the blood.
So they get large cells without the lower Hb conc!!
High MCV (macrocytic anaemia) - Normoblastic:
The following are usually normocytic.
Increased RBC loss is caused by acute blood loss or haemolytic anaemia. Why does this cause macrocytosis?
What 3 diseases could cause decreased RBC production?
Macrocytosis also happens in LATE IN PREGNANCY!!
Due to large compensatory response causing reticulocytosis - the release of reticulocytes into the peripheral circulation.
Bone marrow failure
Aplastic anaemia
Myelodysplastic syndrome
High MCV (macrocytic anaemia) - Megaloblastic:
What 2 things cause this?
Folate and B12 deficiency
Investigations:
Once FBC shows low Hb, what needs to be done next?
What can be done for macrocytic anaemia?
Blood film (peripheral smear)
Bone marrow biopsy to look for definitive cause.
Life cycle of a RBC:
What stimulates EPO production?
Low oxygen levels in the blood stimulations eat kidneys production of EPO
