Pernicious Anaemia Society
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I am currenty battling with my gp to restart my b12 shots following loading doses ( in another post )

I do not have a definitive diagnosis of pa, but I am b12 and folate deficient with neuropathy, the folic acid tabs have been stopped when my last bloods showed b12 2000 plus and folate 22.

In June my mcv was 103, in Sept it was down to 101, I understand that folic acid could have this affect ? If so how would I ever be able to know what my true mcv is ?

Also my heart is scaring me to death, frequently pounding or fluttering, is this the mcv ? And when I get back to my b12 shots would these lower my mcv ?

May I ask another question too ?

In March I had an endoscopy (before the b12 def was noticed) the endo said everything was ok except for a couple of benign polyps which many people have, could this be a clearer indication that I have pa ?

2 Replies

Your true MCV (Mean Cell Volume) is whatever it is measured as (having high folate can't change the measured size). 101 fL per cell is only just above the top of the normal range (96 fL per cell) and, as we all know, ranges don't apply to everybody. It could be that you are normally above the 'normal'.

Low B12 and/or folate can cause macrocytosis, but after three months of treatment it should be OK. There are other causes of macrocytosis. This paper lists some of them and includes a flowchart for diagnosis -

The endoscopy should have picked up if you have Gastric Atrophy - which is what causes PA. Did they take any biopsy samples?


Thanks for your reply fbirder

Samples were taken of the polyps but as far as I am aware nothing else (assumed to be clear as no response from hospital)

If I do not have gastric atrophy would that mean I do not have pa ? I have had the dreaded negative ifa result.

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