False negative PA Tests?

[Bellmore2089]

Back in November, I was tested for B12 for the first time and my results were below the minimum range. My doctor then tested me for PA, and I tested positive for the anti-intrinsic factor antibody (over 2.0), and negative for the anti-parietal cell variety. So wit PA confirmed, I started injecting. Now my B12 level is above normal, and two recent follow-up IF Antibody tests came back negative, though I am still experiencing some symptoms. Seems weird to me. Does anyone have any insight to share?

[Nackapan]

You had a positive intrinsic factor antybody test Rarely wrong. Only sometimes if high levels of b12cin blood

Why testagain?

You need to keep up b12 injections at regular intervals.

Levels do not need testing once on injections

[Bellmore2089 in reply to Nackapan]

My B12 was 260 when I got the positive test of 2.0 for the antibodies. My hematologist tested again routinely for the antibodies while checking my B12 level after two months of injections. In your experience, how often should I be injecting? Once a week?

[Nackapan in reply to Bellmore2089]

It's difficult. Depends on your symptoms.

It is trial and error

What I woujd say is set your b12 injection frequency abd stim to it fir a while.

I've always done thst as if erratic it's even harder t know what hrkus yiu.

I've only recently after over 21/2 years getting clearer symptoms vback when due b12 .

I've read anticipate your injections before symptons return.

Mine have never all gone so I've found that one difficult

So hopefully with a positive PA test with your b12 seemingly in range(depending what measurement usex) you may well progress quicker .

You should be treated by your doctor.

Akso depends on what sort of b12.

I have Hydroxocobalamin as used in the UK. Its supposed to stay longer your system than cynocobalamin.

That differs from person to person too.

Cynocobalamin is usually prescribed every month

Hydroxocobalamin every 2-3 months.

I'm prescribed 2 weekly going on response to treatment.

Doctors can prescribe what patients need .

We know that is nit happening alit of the time .

Do push for proper treatment though so it's on your medical notes.

[Bellmore2089 in reply to Nackapan]

Thank you!

[Gambit62 Administrator]

IFAB isn't very sensitive and gives false negatives 40-60% of the time so a negative is a long way from showing that you don't have PA - where as the initial confirmation is the proof that you do have PA as Nackapan says.Injections should be for life and repeated testing of serum B12 as a way of managing a B12 absorption problem isn't recommended practice by the BCSH

Your haematologist isn't doing you any favours by wasting mo ey on retesting.

Suggest you point them in the direction of the BCSH guidelines on diagnosis and treatment of cobalamin and folate deficiencies which can be found here

onlinelibrary.wiley.com/doi...

These are references by the AAFP in the US

aafp.org/afp/2017/0915/p384...

though the form of B12 used is different - cyanocobalamin and the frequency of inejctions is different. On average cyano is retained twice as long as hydroxo but the early studies comparing the two showed huge variation between individuals - both in how long B12 was reatined in blood and in which form was retained longer so trying to use a one size fits all approach to how frequently injections are needed isn't going to work.

You might also want to point your haematologist at the area of the PAs website that is geared specifically to helping medical professionals improve the diagnosis and treatment of PA

pernicious-anaemia-society....

Received wisdom here would be to determine the frequency of injections that suits you by keeping a diary of symptoms to see when the symptoms return.

[Bellmore2089 in reply to Gambit62]

Thank you!

[EllaNore]

Hi Bellmore2089,

I'm in the US and was diagnosed 6 months ago with B12 D, my levels were 221. You are lucky your doc considered 260 deficient as other docs I've seen don't think 221 is a deficiency but my GP did. 221 and 260 ARE deficient! Especially if you are showing symptoms. My GP even told me I don't have intrinsic factor before I had an IFAB test. I few weeks later, after having started my loading doses, I tested positive for no intrinsic but after an endoscopy, no parietal cells were found. I am injecting daily with cyano. I have just ordered Hydroxo from Germany from apotal.de and am anxious to get it as it is supposed to stay in your system longer. The cyano is helping me, but once I took Methylcobalamin, and there was a big positive change in my symptoms. But I can't find it in single dose ampoules for US, so I am getting Hydroxo as that is what the UK uses and they seem to be doing better on it than I am on cyano. The cyano is quite thin and light in color compared to pure Methyl so I noticed a difference in that right away. I am curious to see what Hydroxo looks like. My cyano is twice as expensive from canada than the Hydroxo from Germany - Even with high shipping costs to US.

So far none of the 10 or so different docs I have seen since being diagnosed understand B12D or PA. Not my GP, my gastro or my hematologists. Googling for PA docs in the US is a no go. There just isn't anyone that knows about it that I have found. The only support I found was in the wonderful UK. The PAS site and this forum were where I found the most support. This forum is awesome and a life line to sanity really. Everyone here has been very helpful and if it wasn't for all these great people, I would still be getting one jab a month and be totally bed ridden and unable to function at all. Thanks to their personal experience and trials and errors, many others have benefitted.

I just had a new hematologists say that he thinks my IFAB test was a false positive and he also said my B12 at 221 was barely deficient and that I wasn't that bad. so your 260 he would not consider you B12d. US levels are too low to meet the deficiency mark. He may not think I am low but he did not see me when I was crawling on the floor and my face was distorted in pain, confusion weakness and dizziness. Had I not learned what I learned here, I would have been totally confused with what he said and I would have been getting down on myself crying and confused. But I know that a positive IFAB test is like Gold and to hold on tight to it. Even if they try to dispute it as a false positive. Also, you don't have to be anemic to have PA. PA is advanced B12 D.

I just had tests a couple days ago. My MCV is 97.8 the normal range is 81-99FL. so he said that my RBC are only slightly enlarged (macrocytosis). that is after 6 months or daily injections. so why still so enlarged? 97.8 is large enough for me!! My folate is 13.29 normal range is >5.38ng/mL , but I do feel that is a little too high. which can hide or confuse a B12 reading. I don't take folic acid. So wondering why it is that high. Anyway, my point is that so far all the docs don't think I am that bad, but they aren't ME and according to my symptoms I am quite bad. So I self inject and take care of myself the best I can with the help of these wonderful, experienced, B12D sufferers. The US is far behind in this and refuse to learn or look outside the boundaries to help us. I hope they can at least follow in the UK footsteps one day. Even though it is not all that great there either, it is better than the US.

Good luck to you. Hang in there. You are on your own in the US. I guess we all are! but you came to the right place