Pernicious Anaemia Flashcards
What are the 3 general causes of low B12?
Pernicious anaemia
Insufficient dietary b12 (usually vegan)
Medications
What medications can reduce b12 absorption? (2)
PPIs
Metformin
What are antibodies produced against in pernicious anaemia? (2)
Parietal cells
Intrinsic factor
Where is intrinsic factor produced?
Parietal cells of the stomach
Where is b12 absorbed?
Distal ileum
What is the function of intrinsic factor?
Essential for absorption of b12
What neurological symptoms are found in pernicious anaemia? (5)
• Peripheral neuropathy, with numbness or paraesthesia (pins and needles)
• Loss of vibration sense
• Loss of proprioception
• Visual changes
• Mood and cognitive changes
What is the first line investigation in pernicious anaemia?
Intrinsic factor antibodies
What autoantibodies are found in pernicious anaemia? (2)
• Intrinsic factor antibodies (the first-line investigation)
• Gastric parietal cell antibodies (less helpful)
What is the treatment for all patients with b12 deficiency?
Intramuscular hydroxocobalamin
How long is intramuscular hydroxoxobalamin given in patients with neurological symptoms? And without neurological symptoms?
• No neurological symptoms – 3 times weekly for two weeks
• Neurological symptoms – alternate days until there is no further improvement in symptoms
What is the maintenance management of pernicious anaemia?
2-3 monthly injections for life of Intramuscular hydroxocobalamin
What is the maintenance management for people with dietary related b12 deficiency anaemia?
oral cyanocobalamin or twice-yearly injections of Intramuscular hydroxocobalamin
If someone is both b12 and folate deficient which do you replace first? Why?
B12
Giving patients folic acid when they have a B12 deficiency can lead to subacute combined degeneration of the cord, with demyelination in the spinal cord and severe neurological problems.
