Intrinsic factor: I’m confused. Does... - Pernicious Anaemi...

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Intrinsic factor

Dragonwalker profile image
15 Replies

I’m confused. Does negative IF mean you have the enzyme or not? Or you have the antibodies? Or not?

Pleased to say my B12 count at 8 weeks was excellent - 2000 - so the 12 weekly jabs may be working and sufficient. So why am I getting neuro symptoms after 5/6 weeks? Pins and needles, the staggers, brain fog, stabbing pains in my feet, ibs.

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Dragonwalker
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wedgewood profile image
wedgewood

If the Intrinsic Factor Antibodies Test reveals ‘negative’ , it CAN mean that you do not have P.A. But the test is very unreliable .In fact about 50% of the time , you.can have PA even with a negative result . I heard it explained somewhere that once the antibodies have achieved their goal, i.e. destroying the pareital cells in the stomach that produce the Intrinsic Factor and Stomach acid , they just disappear as they have nothing to do . Sounds logical , but I don’t know if it is true . But the fact remains that many people have P.A. and test negative to the antibodies. GPs should know this . Doctors should be treating the symptoms of P.A. .

You are getting symptoms after 5-6 weeks because you need an injection every month, so keeping the symptoms at bay . I need an injection every week . I have a friend who needs an injection twice a day , and an acquaintance who finds 3 monthly fine . Yet another friend who self-injects monthly . We are all different . No need to test for B12 once treatment has started — waste of time .

fbirder profile image
fbirder in reply towedgewood

The antibodies would be present all the time. Otherwise new Parietal cells would grow to take he place of the destroyed ones.

wedgewood profile image
wedgewood in reply tofbirder

It was something that I read that a member had sent in , which stated that once destroyed , the pareital cells did not regenerate . But I did say that I didn’t know if it was true . I will try to find it again . I don’t know if there was any scientific evidence .

Gambit62 profile image
Gambit62Administrator

negative means that the test didn't identify presence of IF antibodies above the general noise level of other chemicals in your blood that have a similar mass and as a result are difficult to distinguish from IF antibodies.

As wedgewood says the test isn't very sensitive which means that it gives false negatives 40-60% of the time so a negative doesn't rule out PA as the cause of an absorption problem. A false positive is rare unless the test is done too close to B12 supplementation which means it can be a useful test - just that it doesn't rule out PA if it comes back negative.

Your B12 levels will be off the scale after an injection and then fall over time - but how quickly the B12 is removed - mainly by your kidneys - varies a lot from person to person.

High levels post loading shots don't mean everything is okay.

Suggest that you keep a diary of symptoms in relation to shots. If symptoms subside and then return then that implies that you need more frequent shots.

On the other hand if you have nerve damage as a result of the B12 deficiency it can take a long time to repair.

fbirder profile image
fbirder

For some, unknown, reason people with sky-high levels of B12 can still have symptoms. It obviously has nothing to do with the known pathways that B12 takes part in, otherwise MMA and/or hCys would be raised. They aren’t at all unusual in most people that need frequent jabs, so we know that there is plenty of B12 getting into the cells.

The PAS is involved with some ongoing research looking at those who need very frequent injections and those who survive on the standard 3-monthly jabs.

Early results show that there is a difference in the biochemistry of those two groups. But a lot more work will be needed to identify those differences and what they mean.

That’s one reason why serum B12 levels are pointless for determining injection frequency. Unfortunately doctors like using nice hard numbers to determine treatment, rather than patient experience.

It’s not hard to see why sometimes.

Eowyn1 profile image
Eowyn1 in reply tofbirder

in one of the hundreds of blood labs done on me over 4 years, I found out that I have something called the MTHFR mutation. So apparently my body's myleination process is impaired. I wonder if that is a factor in those of us who need much more B12 than others? Maybe advanced age is also a factor ? It is so frustrating because it all seems so random. I have a friend who is perky and feeling fantastic with once a month injections while I do ok on every other day.

fbirder profile image
fbirder in reply toEowyn1

There is a lot of nonsense on the interwebs about MTHFR. Almost everybody has at least one mutation. Only one mutation (homozygous for C677T - carried by 9% of Europeans) has been shown to have a possible negative effect is some people. Any possible problem can be fixed by taking 400 mcg of methylfolate a day instead of folic acid.

Eowyn1 profile image
Eowyn1 in reply tofbirder

good to know, I have been taking methylfolate for a little bit. I will continue. There is just so much information out there about everything, it can be so confusing the stupid from the factual, I was starting to wonder if I really needed the "methyl" folate or if I could opt for a cheaper brand. So thanks for info!

Cherylclaire profile image
CherylclaireForum Support in reply tofbirder

I have high hopes for the PAS research - but my biggest hope is that the eventual test will not be confined to those who have had a concrete Pernicious Anaemia diagnosis, but will include others like me who have a B12 deficiency/ functional B12 deficiency without a cause being given - and yet cannot manage to control symptoms without frequent injections.

After all, the test for PA is only right half the time, and most people won't get 2 chances !

mummychelle79 profile image
mummychelle79

You have had good answers to your question about the IF test, so I won’t add to that!

Re your levels - please don’t go by what your levels are. Your dr is not supposed to ever test your B12 again once injections have begun. This is because it gives a false high reading. As you are experiencing symptoms, you are likely to be full of B12 that is simply not getting into your cells. After injections begin, your dr should be only using your symptoms to decide if you need earlier treatment.

One big concern to me in your post is you mentioned a couple of symptoms that are considered to be neurological. The treatment when you have neurological symptoms after the loading doses is alternate day injections until no further improvement in symptoms. After that it should be no less often than once every 2 months. People who had neurological symptoms should never be on 3 monthly injections.

Your dr is seriously under treating your condition. They are most definitely not treating you in accordance with the BNF guidelines (page 994 of their book by the way if you want to show your dr). You need to ask your dr to treat you correctly. Symptoms can become permanent if not treated within 6 months. So you are at risk of some of these being with you for life now. The sooner you get on alternate day injections, the more likely you are to recover.

My dr prescribes me B12 to inject at home every other day. This has been a god send to me and has given me my life back! Many drs won’t do this though, and many won’t give the injections as often as you need them. You are, however, able to order B12 to inject from online European pharmacies as long as it is for personal use. There are thousands of people that do this in fact! It may be that you need r look at this route depending on what your dr says about more frequent injections. However, as they tested your blood after starting treatment, I won’t hold out much hope that your dr is going to know enough to treat you correctly. But good luck!

Dragonwalker profile image
Dragonwalker in reply tomummychelle79

Thank you for the valuable advice here. I realize several of my symptoms are neurological and that has been scaring me. They weren’t really evident for more than a couple of months before I went for my first test and they clear within two/three days of an injection. But they come back after about five weeks. I self injected 10 days ago and feel fine but will go entirely by my symptoms from now on. I will keep a diary.

Eowyn1 profile image
Eowyn1 in reply tomummychelle79

symptoms can become permanent if not treated within 6 months? Well I wasn't treated for 4 years, hmmmm. This gives me a more realistic view of what to expect of my old body. Thanks for the info.

Eowyn1 profile image
Eowyn1 in reply tomummychelle79

OK my question is - with every other day injections, why is the B12 not getting into my cells?? Do I need to eat more vegetables? Drink carrot juice? Milk a cow?? Get more vitamin D? The people at the place where I get my injections really don't know much at all about B12 deficiency or recovery. They want to sell me more pills or give me IV's -- yuck on both counts. I just found a nurse practitioner who I feel I can work with and I am going to get my vitamin D, folate and ferritin levels tested next week. This is all very confusing. If you have any advice on other blood things it is helpful to check, let me know and I will run it past the nurse.

Ryaan profile image
Ryaan

Blood test doesn’t show B12 levels over 2000 even if it’s higher, it only goes up to 2000 (it has an arrow next to it meaning “greater than” 2000.

If you’re injecting frequently then the levels don’t matter. They will always show high levels but you can still have symptoms if you’re not injecting frequently enough.

Alfabeta profile image
Alfabeta

Hi

I was diagnosed b12 deficient over three years ago and put on the 12 week injection cycle after the loading doses. My symptoms return during week 6/7 even though I take oral b12 and multivitamin tablets and b12 tablets as well as ensuring I get enough b12 in my diet (I’m a vegetarian so I have to make sure my food provides b12).

My doctor sends me for a blood test when I ask for 8 weekly injections and always refuses as I have enough b12 in my system.

Although my symptoms have changed/reduced, I assume that I am getting better and, as my deficiency existed for a long time before treatment, I will have to accept the possibility that the damage to my nervous system may be permanent.

There doesn’t appear to be any quick fix to our condition - good luck.

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