Okay, so I've been thinking a lot about this, but if you no longer have intrinsic factor why would your body continue to make antibodies to intrinsic factor. I'm wondering about this as I keep getting tested by doctors for IF antibodies with no success, but I was told 15+ years ago when I was diagnosed with PA and megaloblastic anemia that I no longer had IF. So if I no longer have it why would my body "attack it" and how would you prove that on a test. You couldn't right unless you became megaloblastic again; which at that point, one would be near death again with even more long term damage. Am I over simplifying this? Does this make sense to anyone else. Correct me if I'm wrong, please, and point into a right way of thinking if I'm totally off base.
Thought about Intrinsic factor - Pernicious Anaemi...
Thought about Intrinsic factor
Greater than 90% of patients with PA have anti-gastric parietal cell antibodies. These antibodies attack the special cells of the stomach that produce intrinsic factor and stomach acid (parietal cells). I am not sure whether in every case of PA these are completely wiped out or in certain cases just a large enough proportion are made nonfunctional that enough B12 cannot be absorbed orally to make up for losses.
southtees.nhs.uk/services/p...
Without functioning parietal cells, intrinsic factor is not produced. With no production of intrinsic factor, there might no longer be any antibodies to intrinsic factor. I don't understand why parietal cells do not recover but I might speculate that the body keeps rebuilding them and the antibodies to parietal cells continue to attack them. But I'm really not sure.
interesting 1965 paper summary:
"A patient with pernicious anemia was treated with prednisolone, 20 mg daily, for 4 months. During this therapy, there was a return of acid and intrinsic factor secretion, normal vitamin B12 absorption, and a regeneration of gastric mucosal glands containing abundant chief and parietal cells. Although there was a decrease in the titer of intrinsic factor antibody in the patient's serum, there was no change in the titer of parietal cell antibodies.
This steroid effect is consistent with the hypothesis that gastric mucosal atrophy in pernicious anemia is due to autoimmune destruction of the gastric glands, and that prolonged suppression of these immunologic processes may lead to mucosal regeneration with acid and intrinsic factor secretion."
gastrojournal.org/article/S...
So immune system suppression does actually have the potential to get B12 absorption working again to a degree even in PA. Obvious problem with that being your immune system is suppressed and if you were to catch some normally mild infection it could be much more serious.
Super, thank you for the response. I have a gastro appointment next week and as I'm reading this it will be very helpful. I hope to have them write me up something that I can keep that explains my PA situation for future doctors I may have; essentially to prove and explain my PA. My records of diagnoses have been lost long ago and I need to edumecate myself so my appointment is thorough and hopefully not a waste of time. So it is parietal cells I will be asking them about in regards to Intrinsic Factor. Again, thank you as this is most helpful.
One way to determine how advanced the destruction of your Parietal Cells are is to watch for low or no gastric acid hypochlorhydria, or achlorhydria respectively. Parietal Cells not only produce IF but also gastric acid. If they are completely gone then you will have achlorhydria. The best way to test this is next time you have an endoscopy (gastroscopy in UK) ask your GI doc to measure the fasting pH of your gastric juice. They will just suction some juice out and test the pH. I had this done and my pH was 6 which is achlorhydria. Normal fasting pH is 2 to 3 or very acidic. Another simple way to gauge is to have your serum Gastrin tested (a simple blood test). If you have PA and your serum Gastrin is very high then that indicates you either have hypochlorhydria or achlorhydria. My serum Gastrin is above 1000 with the normal high being 400. Rexz
Thank you —Very useful information Yet when asked a gastroenterologist about having my stomach acid tested , he said that it was only done in research situations ! So mine was not tested . So I did that simple bicarbonate of soda test , and found I had either low or no stomach acid . But it’s obviously not very scientific !
Hi wedgewoodI had my gastric pH test at a medical university hospital. Maybe that's why they did it.
I tried the baking soda test and did not belch at all which is consistent with achlorhydria but I didn't trust that test as there was no empirical data or measurement other than a timed belch...🙊
The next best thing to roughly gauge is the serum Gastrin blood test.
Hope you are well today, Rexz
I asked the gastro bod about that test but he'd no idea what I was talking about 🫤
The way I personally handle the IF antibodies etc. is there is a lot of information and no real understanding. It is moot to me as I self treated first by symptoms which I eliminated and now self treat for healing my neurological symptoms from having been B12 deficient off and on my whole life staring at birth.
I am going with robust treatment now is the best way to lessen the risk in the future.
I totally agree. Self Treatment is the way to go. I just want my diagnoses on paper in hand and to have an understanding of what it is for if my kids ever end up with it or if I ever can't order my b12 from overseas. I'm in the USA.
Simply think of it as a vaccine. Vaccines that children receive as a child such as measles, polio, tetanus etc. cause your immune system to produce antibodies against those pathogens and those antibodies are with you for life. Some may need a booster at some point but most do not. In our case our immune system has self vaccinated us as we have been exposed by what our body thinks is an invading pathogen, IF. In advanced stage of PA when most or all of your Parietal Cells are destroyed, these IF antibodies most likely will lesson over time but will always be there. Forever on the alert, hunting for that, what it perceives as bad, IF.
Rexz
Thank you for that!!!
Hello PaintLadie, Hmmm, I see totally what you are saying. It makes perfect sense. Now, in my case when I first went to a hematologist he said let's test you to see if you are producing any intrinsic factor. The test came back quickly while I was waiting in the room. He came back in and said, "you have plenty of intrinsic factor, therefore you do not have anemia". He then said, "there is no way you have anemia of any kind" and then looked at my wife and said "your husband is a hypochondriac" pointed to his head and said "it's all in his mind". He then said, I will go ahead and order an IF test but of course, it'll be a waste of my time and yours. The test came back a week later as positive for IF-blocking antibodies (not parietal cell). So my problem is supposedly not that I do not have any intrinsic factor, but that those antibodies block the intrinsic factor from binding to B12. I don't know if this helps your situation at all, but what I also get from your statements is the frustration you are suffering through due to doctors who don't seem to know enough about PA and in some cases may not seem to care or "something or another". One other point, I thought or at least in my case the antibodies attack the B12, not the intrinsic factor. Hope any of this helps. MJat.
Yes, this is very helpful. When I was diagnosed I was very young and very sick. I did not know how to navigate the medical system and did not have a trusted adult to help guide me. I was put on monthly shots and eventually was unable to get my records from the private practice that diagnosed me after switching doctors. I was megaloblastic and was told I had no IF that is what I was told. That I had PA and would be on B12 shots for the rest of my life. Since then I have had nothing but negative IF tests. They can not find antibodies so they now say I do not have PA.
This after like 15 years of treatment for PA albeit poor treatment, but continuous treatment nevertheless until recently as I had to switch doctors again. Long story it is obvious I do have PA and I am having to SI and no longer have a B12 Rx (I'm in the USA), but I would like to get my ducks in a row. The gastro doctor I figure is my best bet to get a written diagnoses, rather than the blood tests, since he is familiar with the atrophy in my stomach.
I've already had 2 hematologist take my b12 away and one refuse to see me as the IF antibody test they ordered was negative. I must have a digital red mark as they had me test before I would be allowed to make an appointment. I just need to know what to ask the gastro doc for when I see him next week. My new doc is now not prescribing me as she is dead set on me seeing a hematologist. I will be switching doctors once I get this diagnoses on paper to someone that does not meet "clinical insanity standards" and will not force me to yet again see a hematologist.
Clearly they do not understand PA as it includes many body processes (I also have methylation issues) not just the blood and I'm trying to make heads or tails of it also, so I can I better advocate for myself or children if need be and not waste so much money on the same bloods and follow up tests.
My thoughts are it's not you it's the machine that they test us with they are not capable of testing for low b I went for testing my b vit was very high the first time I didn't bother to say anything to Dr . You know that It0spossible
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