parietal cell test positive then negative

[Confused1806]

Has anybody had experience with a positive gastro parietal cell blood test. And then a few months later then had a negative result? I have a gasto appointment in may but in the mean time i dont understand why my test results have changed in a matter of 2 months.

[wedgewood]

I never had the gastro parietal cell test . I had a positive Intrinsic Factor Antibody test .which is the usual test that is carried out . But we all know that that the IFAB test will sometimes detect antibodies and sometimes not . I assume that the gastro parietal test is similar . We once had a scientist on this forum explain this feature which occurs with the antibodies .

A positive test is extremely accurate , but a negative one is about 50 % inaccurate. Well the scientist explained that it’s not inaccurate —Sometimes the antibodies appear , sometimes they don’t .

I’m at a loss to understand why you had another test . A positve test settles the matter —you have P.A. No need for another test .

It is not well known by doctors that this happens . Many believe that a negative test indicates no P.A. This is not the case .

Best wishes .

[Confused1806 in reply to wedgewood]

Long story with me i was referred to a gastro back in november but of course i have a number of symptoms that come and go and at points get worse so my gp had emailed the gastro directly as my gps at abit of a loss what to do and they suggested a number of bloods which again included the liver autoimmune test which showed the gastro parietal cells. I did have an IF test which was negative. Seems all so hit and miss with theses tests. Finally have a gastro appointment next month just praying this double results doesnt complicate things furthur. Thanks for your reply however good to know a negative doesnt 100% mean negative.

[wedgewood in reply to Confused1806]

It is stated in the new NICE guidelines that PA patients can have a negative test . Trouble is that the GPs don’t read the guidelines . I asked my GP and she didn’t know about the guidelines . They are only guide lines -nothing more ! PA is referred to as Autoimmune Gastritis in the guidelines .

[FlipperTD]

Scientist, not medic. This is a bit long, but stick with it.

Antibodies are 'funny old things'. There are very many sorts and types. Detecting them is complex, and the a for detecting one won't necessarily work for another. Detecting IFAb for example: there are numerous different methods for detection, and these are increasingly automated methods. Detection of Parietal Cell Antibodies typically will use something called 'Indirect Immunofluroescence' which is a microscopic technique, which is very different to the methods used for IFAb.

We've all learned a great deal about antibodies with our dear old friend 'Covid', and learned that antibodies come and go. Typically, you get a stimulus [in Covid's case, a virus] and our bodies have very effective surveillance systems in place. We immediately switch on a response to produce antibodies, but also other cellular methods too. The amount of antibody present rises, 'sorts out the problem' and then the amount of antibody will reduce once it's no longer needed. We do however have 'memory cells' that will remember 'I've seen this antigen before!' and kick off production when it faces another challenge. Of course, the little virus will have mutated, and no longer be exactly the same, so the secondary challenge might not be quite as effective, and the more mutations, the more of a challenge it is.

Some immune challenges will stimulate a 'broad spectrum' response, and consequently levels of other antibodies will rise too, in a non-specific manner. If you get bitten by a horse-fly, for example, then they're very effective at producing a broad spectrum response which will eventually damp down in a few weeks.

Quantitation of antibody response is another matter. for some antibodies, the lab will perform 'serial dilutions' [1 in 2, 1 in 4 etc] and test the dilutions to see how far the sample can be diluted before the reaction no longer takes place. As antibody tires rise and fall, then the level at which they can be detected will vary. In this case, it could be that yours were 'just detectable' and the second time, they had dipped under the threshold. It's hard to say, but in general, it's down to 'if you don't believe it, do it again after a few weeks/months.' If you've had two results that are different, then it's hard to say which one is correct, because in all probability, they may both be correct anyway.

Performing the tests is the easy bit; interpreting the results can be more of a challenge, and that's why it's handy to have the full clinical picture before us. That's why we have consultants!

Good luck.

[wedgewood in reply to FlipperTD]

Thank you so much for the invaluable explanation . But will GPs believe it .? I've read on this forum of so many instances where a negative Intrinsic Factor Antibody test has resulted in the patient being told that they do not have Pernicious Anaemia , inspite of being ruled out of having any other causes of B12 deficiency, but having symptoms . We need that explanation in the NICE guidelines to B12 deficiency.

[FlipperTD in reply to wedgewood]

Thank for for your kind words. I'm afraid it's 'Horses and Water' as far as getting folks to understand. I've just noticed a spelling error: it should have been antibody titres, not tires!

[wedgewood in reply to FlipperTD]

But when scientific facts are the subject , and there’s concern for health and appropriate treatment of patients , there should be no Horses or Water involvement.

Yes I know that it’s beyond your powers to influence it . Thank you again . This forum much appreciates your input .

[Confused1806 in reply to FlipperTD]

What a brilliant way of explaning it thank you. Thats the concern for me i have no idea i am no where near a medic of any sort but with alot of my symptoms i suspect PA but due to negative IF and now this double result im worried this may all be overlooked and left. I just hope that the gastro i see next month is expereinced enough to make a diagnosis based not soley on test results.

[wedgewood in reply to Confused1806]

You could try getting another test . If positive , that’s it . Then there’s no need for another test . I have heard that our former Chairman needed three tests until a positive one appeared.

[FlipperTD in reply to Confused1806]

PA is a clinical diagnosis, and as such it shouldn't rely purely on numbers in tests. That's why we have doctors.

[Nackapan in reply to FlipperTD]

Exactly . Seems the test will confirm the 'clinical picture' If it doesn't and nothing else found the diagnosis should remain.Treated as per guidelines.

Doctors are relying to much on tests and not on clinical skills and experience.

Time constraints

Lack of face to face

And lack of mentoring

Also the fear of being sued or needing hard evidence to prescribe .

It appears to balance budgets

Covering their backs.

I went through 6 gps.

One used her vast experience and was up for the challenge as she put it, to get me right.

She stood up to peers .

Waded through many tests to eliminate other things.

Eventually believed and realised I wasn't clinical depressed.

Or had mental health problems.

Or it was the menopause .

Or 'an act '

I trialled 2 drugs as she nearly gave up saying if I wouldn't try things how could she help .?

She then saw that didnt work.

Not once did she stop or threaten to stop b12 Injections .

I realised at times she was simply trying to reduce anxiety and thought b12 a placebo.

Definitely amazed all symptoms cpuod be b12 deficiency.

But shed never seen such a low reading??

Probably as not on regular bloods for everyone.

It was hard work second guessing what her thoughts were .

Her background was gynae so convinced the menopause/ changes a trigger and then convinced me to try HRT .

That failed .

Then tried to get me 9n antidepressants to raise serotonin levels.

Pror to thus 3 neurologists wanted me on amytripyline.

Eventually trialled this in a crisis of the worst migraine going down my spine .

She soon got me off it . I had to buy a pill cutter to wean off 10mg .

Unusual I was told ??

She was the one that used her vast experience.

Clinical skills .

Kept me on 2 weekly b12 injections despite alot of opposition .

Also still obviously intrigued as didn't understand what was going on .

On one consult a receptionist came in telling her asking her if everything okay as I wax in there 'too long '

She simple dismissed them and told me to book double appointments in the future .

Not only have I lost this G.p.

Surgery closed .

She probably retired now .

Face to face appointments do not seem to happen much.

The surgery shut a yesr ago .

The new surgery.

I don't even know who or what the Gps look like.

Never met any of them.

All messages from nurses to them.

Or a text reply from a letter sent .

Saw a locum a few miles away on their request getting my b12 reinstated .

It was then overruled by a pharmacist admin??

Remote doctoring will not promote or educate clinical skills .

Observational skills

Watch and wait of old doesn't seem relevant now??

Just observatiins of what we are up against.