Lecture 13: anaemia, B12, folate Flashcards
State 3 symptoms of anaemia.
- shortness of breath
- headaches
- angina
- weakness
- lethargy
- palpitations
- confusion
- pain/tiredness/discomfort in legs when walking
State 3 signs of anaemia.
Tachycardia Pallor Systolic heart murmur Hypotension Tachypnoea (abnormal fast breathing)
A doctor sends a sample of blood taken from a patient for a direct Coombs test.
What is measured by this test?
Ab bound directly to the surface of RBCs.
Used when immune-mediated haemolytic anaemia is suspected.
A patient presents complains shortness of breath, lethargy, frequent headaches. A full blood count shows her Hb to be 90g/L (normal: 115-165g/L). GP is aware of that they’ve been taking medication for the past 12 months and suspect that this contributes to her current symptoms.
What medication could have contributed to the symptoms and blood test result?
NSAIDs
- aspirin
- Ibuprofen
- Naproxen
These can cause gastric bleeding in patients so would cause chronic blood loss= anaemia.
A 35yrs woman is diagnosed with iron deficiency anaemia.
What would be a physiological response to this condition?
- Tachycardia
- increase 2,3-BPGlycerate so Hb has a lower affinity for O2
- Hypervolaemia
- An increase in EPO production
- A right shift in the O2 dissociation curve so O2 can easily dissociate from Hb.
Define anaemia.
Lower Hb concentration than the normal range for a person of the same gender, ethnicity and age.
Insufficient production of which hormone in chronic kidney disease may result in anaemia?
Erythropoietin.
Insufficient absorption of which nutrient underlies the condition pernicious anaemia?
Why is this nutrient not absorbed as well in pernicious anaemia and why does the lack of this nutrient cause anaemia?
Pernicious anaemia = vitamin B12 deficiency
In pernicious anaemia, there is a lack of intrinsic factor and this means that not as much vit. B12 can be absorbed in the SI.
Normally vit. B12 is used in RBC DNA synthesis so a lack of this nutrient means less EPOsis in BM.
The serum Fe level is a reliable indicator of iron deficiency & iron overload.
True/False (why?)
False.
Overall serum Fe level can change with other conditions (inflammation, infection, cancer, liver disease) so transferrin saturation, reticulocyte Hb count is used instead.
A low vit. B12 level can be the cause of sideroblastic anaemia.
True/False (why?)
False.
Sideroblastic anaemia is caused by a low vit. B6
A low vit. B12 level can be a cause of a macrocytic anaemia.
True/False (why?)
True.
Lack of vit. B12 means delayed nucleus development because there is less DNA synthesis in the BM: the cytoplasm matures quicker relative to the nucleus. As a result, the RBC becomes bigger than normal before the nucleus can be extruded. As a result, the spleen sees these RBCS as abnormal so they are destroyed.
People who are haemolysing need regular folate replacement.
True/False (why?)
True.
Folate is needed for RBCs’ DNA synthesis in BM. People who are haemolysing are using up their body’s folate stores and these can only last for a few months. Therefore, regular folate replacement therapy is needed.
A normal ferritin level excludes iron deficiency anaemia.
True/False (why?)
False.
A low ferritin level indicates Fe deficiency but a normal/higher level will not exclude it.
Bite cells or blister cells are classically seen on a blood film if patients are vit. B12 deficient.
True/False (why?)
False.
This is seen in patients with G6PDH deficiency as G6PDH is used for protection against oxidative stress.
What is haemosiderin and what is it composed of?
Insoluble iron storage molecules
Made of ferritin, proteins and lipids