pernicious anaemia

Question 1

what is pernicious anaemia?

Answer 1

autoimmune condition where antibodies form against parietal cells or intrinsic factor.

parietal cells of the stomach produce intrinsic factor , which is essential for absorption of b12 in the illeum.

Question 2

what neurological symptoms are caused by b12 deficiency?

Answer 2

Peripheral neuropathy with numbness or paraesthesia (pins and needles)
Loss of vibration sense or proprioception
Visual changes
Mood or cognitive changes

Question 3

which autoantibodies should you test for when suspecting pernicious anaemia?

Answer 3

1. Intrinsic factor antibody is the first line investigation

2. Gastric parietal cell antibody can also be tested but is less helpful

Question 4

what is the management for pernicious anaemia?

Answer 4

1mg of intramuscular hydroxycobalamin 3 times weekly for 2 weeks, then every 3 months

if there are neurological symptoms:
1mg every other day until the symptoms improve

Question 5

why should you correct b12 first before correcting folate in a combined deficiency?

Answer 5

Treating patients with folic acid when they have a B12 deficiency can lead to subacute combined degeneration of the cord.

this is demyelination of dorsal and lateral collumns of the spinal cord, which can cause sensory deficits