B12 active test for P.A?

[Thyroid1892]

I’ve previously had a B12 serum test (suspected b12 deficiency) from my gp which has come back normal. I’m looking at getting some private tests done but am a bit confused if anybody can help?

I have seen that for some people who suspect pernicious anemia the intrinsic antibody test is useful for further diagnoses, but that test is almost double the price of active b12 test. So essentially what I’m asking is that, if I’m suspecting pernicious anemia, could a b12 active test prove this? Without the need for antibodies test? I’m just looking for some sort of confirmation before committing to b12 injections long term. Cheers.

[Nanaedake]

Have you tried asking your question on the Healthunlocked Pernicious Anaemia forum? They have expert knowledge.

As far as I'm aware, the active B12 test will tell you how much B12 is available for your body to use but if B12 is low, it won't tell you the reason for it. If a blood test comes back positive for intrinsic factor antibodies that evidences pernicious anaemia and consequential low B12. However, not everyone with pernicious anaemia returns a positive intrinsic factor antibodies test so I believe you can still have pernicious anaemia even if you don't have a positive blood test. Perhaps it depends on having low B12 together with symptoms. There are other tests available, although perhaps not on the NHS, to rule out a problem with B12 absorption such as MMA and Homocysteine so you need to ask the experts first.

[Thyroid1892 in reply to Nanaedake]

Ah I’ve found the P.A section! Thanks again.