Macrocytic anaemia Flashcards
What test should be done if you see microcytic anaemia on blood test?
Peripheral smear to show if the neutrophils are segmented or not.
What is macrocytic anaemia?
Low haemoglobin
High MCV >100
What are the two types of macrocytic anaemia?
Megaloblastic (hypersegmented neutrophils)
Non-megaloblastic (no issue with neutrophils)
What are types of megaloblasts macrocytic anaemias?
Vitamin B12 deficiency
Folate deficiency
What are types of non megaloblastic macrocytic anaemias?
Alcohol abuse
Liver disease
Congenital bone marrow failures
What causes vitamin B12 deficiency?
Pernicious anaemia
GI disease
What causes folate deficiency?
Dietary
Increased requirements in haemolysis
GI pathology (coeliac)
Which type of deficiency is more common?
Folate deficiency > Vitamin B12 deficiency
How long do vitamin B12 stores last for>
6 Months
How long does folate levels last for?
Folate levels are used up very quickly so dietary deficiencies are common
How is vitamin B12 absorbed into the body?
The gastric parietal cells secrete intrinsic factor - this binds to vitamin B12. This creates a vitamin B12/intrinsic factor complex.
Where is the vitamin B12/intrinsic factor complex absorbed?
In the terminal ileum.
What is pernicious anaemia?
Most common cause of vitamin B12 deficiency.
Autoimmune disease where antibodies against intrinsic factors are made. Causes malabsorption of dietary vitamin B12.
What are the symptoms of pernicious anaemia?
Folate and vitamin B12 deficiency can cause neurological problems
Jaundice (macrocytic anaemia - the red blood cells you make are so big that they’re easily broken down)
Peripheral neuropathy
mood changes
cognitive changes
loss of proprioception or vibration sense
parasthesia
numbness
What test is done for pernicious anaemia?
Anti-intrinsic factor antibodies.
