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Pernicious Anaemia Society
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Seeking advice prior to GP visit (low B12 test)


Only recently found this forum but it looks like a very useful resource so I can see I'll be spending some time reading!

I will try to keep this post short, but I'd be grateful for any advice so that I can be more informed when I see my GP this week (I'm in the UK)

I have recently had a blood test (arranged by a neurologist). I haven't seen the full results yet, but have been copied in on a letter to my GP noting that my Vitamin B12 (118ng/L) and Vitamin D (41mmol/l) levels are low and that she should arrange the 'appropriate supplements"

I was referred to the neurologist from an orthopaedic consultant, who sent me for an MRI and EMG for potential cubital tunnel (These suggested nothing that could be treated by surgery).

The initial symptom that led to that referral for me was pins and needles in fingers, and loss of feeling (something I notice since I am an electrician and work with tools) to the extent I would occasionally drop screwdrivers when gripping them.

The neurologist has referred me for a brain MRI and SSEP, but in the meantime requested some bloods, which appear to have picked up the serious deficiency in B12.

It is of course easy to read a list of symptoms for anything and feel that they fit you, but having now read the ones for B12 deficiency / PA, they seem to match very closely with issues I have been noticing or have lived with - specifically:

intermittent IBS

noticeable decline in spatial awareness in the last 12 months

Loss of memory - specifically forgetting names/words on occasion

tingling/pain in fingers



depression (Was on anti depressants for approx 10 years - stopped last year)

The only medication I currently take is a fairly low dose sleeping pill for insomnia (Something I had put the lethargy possibly down to as it often hits in the morning for me)

I am not vegan or vegetarian, so should be getting enough B12 in my diet I think. I eat a lot of chicken and love Marmite! I do not always eat as healthily as I should, but have improved following a high cholesterol test a year ago. I limited my egg and cheese input from then on, but still have some.

When I rang my doctors to follow up on the consultants letter they had not processed it yet so I made an appointment. I am quite happy with my GP and she seems very thorough, but clearly I will only have a limited time with her, so I am wondering what the best areas of discussion will be with her...

I am not clear yet whether the bloods that were taken included an IF test - if not I gather this would be a way forward to check for PA? Is the Schilling test something that is commonly used in the UK too? Should I expect to see a test for Folate levels if not already taken too?

I've read the NICE guidelines linked from another post which do seem quite clear that the treatment is likely to be injections. regularly at first and then occasionally. Once I got the letter I have been taking some high dosage B12 supplements (2mg daily) but if the issue is PA I gather the body uptake can be much lower.

In one sense it is nice to potentially find a 'cause' for some of the symptoms that I've been experiencing, but of course it also adds new things to feel anxious about!

Apologies for the length, but any advice gratefully received.


13 Replies

Yes, it does sound like your symptoms can be explained by a B12 deficiency.

The correct treatment is injections. The normal regimen is described in the British National Formulary (BNF). Your doctor will have a copy. It lists two different dosing schedules. The one for people with neurological symptoms, like you, is more extensive than for those without. Unfortunately, many doctors stop reading after the first paragraph.

The treatment you need is:

Injections of 1000 ug of hydroxocobalamin, every other day until no further improvement in symptoms, with a review after three weeks. Followed by one injection every eight weeks.

Treatment is for life..

You should be tested for anti-IF (Intrinsic Factor) antibodies as a test for Pernicious Anaemia. Unfortunately this test is not very accurate, with half of all people with PA giving a negative result. Make sure this is done before you start injections. And stop taking the B12 tablets a week beforehand.

The Schilling test is no longer done. It needs radioactive cobalt, which is no longer made.

I'd be surprised if the neurologist didn't test for folate at the same time as B12. But, if they didn't you should get that done as well.

Get all of your test results in a print-out.

Your IBS-like symptoms can be explained by low stomach acid, which would suggest you have Autoimmune Metaplastic Gastric Atrophy (AMGA). This is the condition that causes PA. The immune system attacks cells in the stomach called Gastric Parietal Cells (GPCs). These cells make IF (the protein that escorts B12 from the gut to the blood) and hydrochloric acid.

In AMGA the stomach doesn't produce enough acid (achlorhydria). This means that some foods aren't digested properly, especially protein. When this protein hits the large intestine the bacteria there have a massive party on the unexpected riches, resulting in gas, bloating and diarrhoea.

I fix this by drinking about 40 ml of lime juice with lunch and dinner (and on the rare occasions I have a fried breakfast). Others use apple cider vinegar. I also take a probiotic (Bio-Kult) to keep a healthy mix of bugs in the gut.

You should ask for a referral to a gastroenterologist to give you an endoscopy. That will confirm the gastric atrophy. It will also check for gastric Carcinoids (aka Neuroendocrine Tumours or NETs). These are fairly innocuous beasties most of the time, but it's worth knowing if they're there so they can be monitored.


Your comments on the stomach acid hit a nerve so to speak with me. As someone who suffers from intermittent IBS I will do a little more research on this. As a 61 year old woman I am probably not making enough stomach acid anymore. I do take some acidophilus but quite often forget, are they different from the Bio-Kult or is that just a brand name for acidophillus?


Many thanks for such a prompt and detailed reply!

I am hopeful that my GP is one of the ones who is prepared to investigate and listen, but I will go prepared with the guidelines, which seem pretty clear on the injection treatment.

Given that the treatment seems to be the same regardless of the IF test (perhaps because it's not terribly accurate) what are the benefits of delaying the B12 injections and stopping the tablets in order to have the test? My symptoms seem to have been getting worse recently and affecting work, so I'm keen to get the injections started quickly so that hopefully I can see some improvement.

I guess it may make it easier to ensure ongoing long term treatment if a formal PA diagnosis is given, which would come from the IF test? I have read some stories of people having their injections stopped because of a new doctor, or ignorance of the status of PA.

I will certainly investigate lime juice and Bio-Kult - my IBS symptoms tend to be intermittent and mild compared to many but with occasional flare ups. I had put the tiredness, etc. down to that, but it now looks like it may be the other way round and the IBS was an early symptom of the PA!

I did see a gastroenterologist a few years back about the IBS but they decided there was not much to do and stopped just short of having an endoscopy. I will get my GP to check back and see if they checked B12 at the time (They did take some bloods). If not they might have missed a chance to deal with things much earlier :|

I appreciate your reply and am sure I will be spending a lot of time here for a while!


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Don't delay in getting the injections, just get the IF test before you start them. My nurse did it at the same appointment, just before the B12 injection. Stop the tablets until you have had the IF test as it may skew the results, not that it is very accurate!

After you have had B12 injections it would be pointless in testing B12 levels again, unless your symtoms don't resolve somewhat. Taking the tablets would be fine then, to top up.

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I am in no way an expert in this field (yet) as only just had my first B12 injection. All I can say is I have been fobbed off continually even after my results showed as abnormal. So all I can advise is that if you feel that taking B12 and other supplements may help you, then fight your corner and point out that taking B12 is a hell of a lot cheaper than having an MRI scan. At least if you try it and you have no improvement then by all means look at having more serious medical investigations and read up as much as you can from sites like this. I went in to the surgery with my book on "Could it be B12" so they knew I had done my research and wasn't going to leave quietly.

Good luck and I hope you get well soon.




Many thanks for your reply! Thankfully my GP does seem to be reasonable and open to feedback - it was her willingness to refer (albeit to the wrong consultant as it turned out) that has led to what hopefully is the true cause, so I'm optimistic.

I will certainly be going armed with info though.

Did you notice an immediate reaction to the first injection? My symptoms, particularly the tingling hands, seem to have been getting worse and affecting work, so I'm hopeful that there will be some rapid improvement.



Don't expect a miracle reaction after a single injection, it will take time. Assuming you able able to persuade your GP to give you alternate day injections until your neurological symptoms improve (as per guidelines) it might be weeks or months before the tingling in your hands improves. You could be lucky and notice and improvement after 3 or 4 injections but be prepared for the long run.

Neurological symptoms develop over a long period of B12 deficiency - in my case 4 years - and are not likely to be reversed in the short term. After the usual argy-bargy with my doctor I managed to get alternate day Hydroxocobalamin prescribed (injected by the nurse at first now self injected). I noticed a marked improvement in my mental state after 3 injections and a marked improvement in fatigue after 6 injections however six weeks on the numbness in my feet has not been reversed. The feeling (or lack thereof) has changed in a positive way so I believe that the B12 is working but I suspect that it may be a good few months before it is resolved, iIf it resolved at all. Some neurological conditions are permanent when the deficiency has not been addressed early enough.

You may be lucky - everybody is different - but you should be aware that you might not notice an improvement for some time. You need to stick at it for as long as it takes!

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I had really bad diarrhoea and have had a stomach pain every since my first injection on Thursday. I am due another one tomorrow so will see what occurs after that and see whether the nurse has any input on why.

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Ah. Sorry to hear that. Hopefully maybe just the body adjusting to something it's been missing?

Will be interested in your experience going forward. Are you on a regular dosing course at the moment?




I had the first one on Thursday. 5 more to go, that's if my body can tolerate it.

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tip. take a copy of the letter with you. it might not have got through the system for your gp to read it.


Update - I saw my GP today and (as partly expected) the letter from the consultant hadn't arrived, but she was able to access my results and accept that B12 was too low. She was surprised we hadn't checked it sooner, but looking back it was apparently missed because it was thought it was carpal tunnel, hence the earlier referral to orthopaedic.

The end result is that I am having an IF test on Monday, and the injections starting from Friday next week - although only 6 on alternate days.

She was rushed and didn't seem to recognise the distinction between neurological and non symptoms in terms of time to the next dose (stated that the standard is 12 weeks) but was willing to be flexible if symptoms reoccur sooner.

I guess I consider that progress, though it seems that the NICE guidelines aren't quite as binding nationally as they would suggest, compared to local practise.

She did also say that in our are, 145 is considered the low point, which is a lot lower than NICE state. However, since I came under it it doesn't affect me.

She did mention taking another blood test before the 3 month injection if symptoms were returning, but we'll cross that bridge when we come to it.

My folate was checked and was apparently 'normal' at 6.79 mcg/L.

I did get the rest of my blood test results, but all appear to be within normal ranges.

I do have a couple of follow up questions if anyone has advice to offer:

1. Is there any benefit to taking oral B12 supplements to 'smooth out' any bumps between injections?

2. As I understand it, even if the IF antibody test comes back negative, the treatment should not be changed and I should expect to continue the injections for life and consider that I do have PA, in the absence of any other issues coming forth in the MRI and nerve tests I have booked.

3. If, as seems likely, I have low stomach acid causing my IBS symptoms - should I expect them to improve with the injections? I've seen some suggestions of HCL tablets with pepsin as helping, but not sure if that's marketing over substance..

Many thanks for the assistance already - hopefully I will now start making progress on my symptoms.



Wow! Some really interesting points raised in your subject.

There are so many possibilities. Serum B12 is a pointless exercise at your levels, as further specific testing is required. Stomach acid is very important as mentioned. As I have suggested, you might be tested for Gastrin levels for this indicator, but only if referred to a testing hospital, as Gastrin deteriorates very quickly. As others suggest, don't be lulled into thinking you have something you haven't. IBS is a lovely coverall. It could be IBD or other things.


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