Intrinsic factor and GPC antibodies

[x101210]

I have a question about my test results, I was hoping someone here could help explain to me what it might mean because I’m not confident the doctors I’m seeing know anything about this stuff.

I had a low b12 level (175), along with high homocysteine and high methylmalonic acid. I was then tested for intrinsic factor antibodies and was positive for intrinsic factor antibodies. I then realized there are also parietal cell antibodies that are common in P.A. patients so I asked to be tested for those as well, which was done a month after the other tests and after I already started on b12 injections, and that came back negative. This was actually a little surprising to me because stomach discomfort is one of my main complaints so I just assumed I was positive.

My questions are, are both required for confirmation of a PA diagnosis or just one? Could it have been positive and the b12 injections helped stop the antibodies? Should I be retesting for intrinsic factor antibodies in 6 months or so?

I’m just not sure if being positive in one and negative in the other has any significance at all. At this point I will inject b12 for life no matter what, there is no way I’m letting it get that low again. But if the results have some significance to how I should approach the treatment or follow up of this disease and the other things I should be doing that would be good to know.

Note: I’m scheduled for a Gastro visit soon and will be getting upper endoscopy to see what is going on with my stomach.

Thanks in advance for any info. So glad this forum exists, doctors really know so little about this disease.

[wedgewood]

How right you are in saying that doctors know so little about P.A. That’s why the PAS is such a fantastic life-line for us . You have tested positive to Intrinsic Factor Antibodies , so you have Pernicious Anaemia.

and will need lifetime treatment with B12 injections at a regularity that keeps your symptoms at bay . This varies from person to person and it is not known why this is the case . Anything between daily and 3 monthly . You will find no understanding of this with your doctor . Yes it varies that much ! . I am impressed though that you got tested for homocysteine and MMA . Excellent ! The fact that the Parietal

cell antibody test was negative is neither here nor there .

Yes with PA you will have the gut problems until you have successful treatment . PA patients have low or no stomach acid ( Hypochlorhydria / Achlorhydria due to destruction of the parietal cells . This upsets the stomach flora ( good bacteria ) and allows bad bacteria to flourish , causing gut problems like bloating and pain . Mine eventually disappeared after a course of a probiotic calked Symprove . and B12 injections . It also helped to have an acidic drink with meals -like diluted Organic apple cider vinegar or lime juice etc

Wising you all the best in getting treatment . At least you now know where to come for help .

[fbirder]

The anti-GPC antibody test is negative in 20% of those with PA -

Gastric parietal cell (GPC) antibodies have a low specificity for the presence of pernicious anaemia as, despite being positive in 80% of pernicious anaemia subjects, they are also positive in 10% of normal individuals.

onlinelibrary.wiley.com/doi...

[FlipperTD]

Scientist's, not medic's answer.

I spent many years performing B12 assays, and reflex testing IFAb on low B12 results. Finding a 'definite case' [low B12 and positive IFAb] resulted in a phone call to the GP, and making sure that the message had been received.

We didn't test for Parietal Cell antibodies for a few reasons, but mainly the lack of specificity for PA.

We knew that there was a variable degree of understanding about PA, and one positive IFAb result could be overlooked if the requesting doctor hadn't actually asked for it, hence the phone call to reinforce the message.

We also performed Schilling Tests, [RIP!] and getting those done properly and acted upon was something of a nightmare too. We knew what we were doing, but if anyone else got involved in the process, things could go wrong on occasion.

The important message is that laboratories are staffed by dedicated specialists who are there to help!