Pernicious Anaemia Society

I don't think I have PA but I would appreciate the benefit of your advice please?

I don't think I have PA but I would appreciate the benefit of your advice please?

Hello, the lovely people on the Thyroid board sent me here 😊

After an elevated (subclinical) TSH I've had normal results in the lower end of the range (and negative antibody results) this week.

I have had the results of other blood tests taken in January and with TSH ok now, I'm looking for clues as to why I'm unwell.

My symptoms are chronic headaches, inexplicable periods of tenderness in my body (muscular or joint) feeling stiff, low mood, periodic numbness in my arm and leg, intermittent buzzing and fizzing in fingers and toes, periodic swelling in hands and feet, periodic brain fog and fatigue.

It's been nearly four years. I was always so high energy with practically no headaches ever. My periods are also haywire lately. At the moment every 2.5 weeks, since these bloods I've had 3 in six weeks.

Thank you for helping.

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I don't know why my photo is landscape when posting. Is this unhelpful? I can try again...


Were your iron and vitamin D levels tested?

I'm not a medically trained person but there are others on here who will be able to give you good advice.


I do not think so. I think I have them all and I can't see those

I noticed my HB wasn't brilliant so I've picked up some Spatone this weekend. I was supplementing vit D in Jan (including K2) as I observed the winters tended to be worse for me since feeling unwell these last few years.


The serum B12 test is problematic because it uses ranges based on averages without really taking into account how much people vary and people tend to interpret it as the be all and end all. In fact it's likely to pick up 5% of people who aren't deficient but are okay with serum levels below the bottom of the normal range ... but it also misses 25% who are deficient but serum levels are in the normal range - however most of that 25% are going to be in the low end and your result is quite a way into the range though still in the grey zone.

Your blood work isn't showing any obvious signs of macrocytosis (a classic symptom of B12 deficiency) but as that isn't present for about 25-30% of those who are B12 deficient it isn't a conclusive result either.

Evaluating on the basis of symptoms isn't without its problems because of the overlap with other conditions - including thyroid (which seems to have been ruled out), Vitamin D deficiency, iron deficiency - though does sound that vitamin D is unlikely. On the iron - please be careful as it is possible to overdose on iron supplements if you need them and although your results were low in range they were still in range.

Basically B12 remains a possibility but is a long way from being clear.

There are a few tests that can help clarify - look at waste products that build up if your cells aren't getting enough B12 - MMA and homocysteine - but both can be elevated for other reasons.

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Thank you for responding. I really appreciate it. I did work hard on my diet last year (gluten free alcohol free sugar free diary free diet high in omega 3) and it seemed to really help me. After some months my bad heads lifted, I also had a course of hyperbaric oxygen at this time. I would come out of there pain free. I was able to break free from all medication.

Then two bereavements at the end of the year lead to a loss of appetite and eating badly and it all set me back.

I am moving back towards my dull diet. Please would you give your view, Could I do much harm with some 1,000 b12 a B complex and some spatone?


supplementing B12 at that dose isn't something I would advise unless there is a much stronger case for believing that you have a B12 deficiency AND you have exhausted all possibility of getting a diagnosis and treatment from your doctor - it makes getting a diagnosis in future close to impossible as it skews tests and it can cause problems with B12 transfer to cells that would just need you forever needing a much higher dose of B12.

Do you eat meat/egg/fish? if not I would suggest trying a much lower dose supplement as possible that you have a dietary deficiency.

On B complex and spatone would suggest that you speak to a pharmacist and/or your GP.

Have you been tested for coeliacs? Coeliacs can cause problem with B12 absorption.


Hi and thank you. I will take that on board.

I'm so keen to feel better, I'm disappointed in a way in that I rather hoped a few supplements might sort me out. I thought some suggested in old posts over 500 was an optimum B12.

I do eat eggs and fish. I felt my best eating lots of salmon, shrimp and egg (yokes). I'm adding these in again regularly. I've been gluten free for so long (IBS) that a test is pointless now. I won't touch it as I don't feel good at all. Thanks again.


I know 500 is optimal crops up on the TUK forum and I'm really not sure where it came from. Back to the serum B12 test not being a good one so how anyone can come up with an average and think it applies to everyone I really don't know.

The PAS did a survey some time ago and people reported that on average they needed levels to be 1000 to feel well but this was people who were being treated with high doses - so not applicable to the general population and certainly not a guide to where general population should be.

Understand on the gluten and coeliacs - does sound as if you may be undaignosed coeliacs but if you are avoiding gluten then the effect on the gut and absorption problems would be minimal if it exists at all as the irritant has been taken out of the equation.

You could try looking into MMA and homocysteine.

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At least some mentions of 500 come from "in Japan ..."

However, some Japanese papers refer to pg/mL and others to pmol/L. I suspect that 500 at least sometimes is in pg/mL.

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Thanks Helvella,

in Japan the cut off they use for identifying a B12 deficiency is 500ng/L (think that is about 370pmol/L) - which is about reducing the risk of not catching someone who is actually deficient). This would be looking at people who are specifically presenting with symptoms of B12 deficiency - and I have no idea what happens if there are other overlapping conditions. Using that as an 'optimal level' is completely incorrect - optimal should be about what is right for an individual which is likely to be very different.


Gambit62 Sally Pacholok p11: "We believe a "normal" serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiences begin to appear in the cerebral spinal fluid below 550 pg/ml." She also says she believes "normal" levels should be greater than 550 pg/ml and that in older adults they should be near or above 1000 pg/ml (to prevent disease and for brain and nervous system health).

The whole of the page is about this subject. Are we still seeing this book as a reliable source? I thought we were. We do need some source material to explain our position to doctors which goes beyond "something I read on the internet"!


Thanks Frodo - aware but this is back to the B12 serum test being problematic and needing to evaluate symptoms. In a clinical situation people are going to have had the test done because there is strong evidence but that isn't the case so people are often advised to supplement huge doses of B12 when there isn't any evidence of a B12 absorption problem leading to other problems.

The 1000 refers to people who are being treated with B12 shots - not the general population - it is likely to be very skewed by functional B12 deficiencies. Even then it is an average. 1000 would be far to low for me personally following the fact that I've had injections.

Back to optimal being the level that is right for you as an individual.

The book is still a reliable source but things in it need to be taken in context not quoted out of context

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Do you have a result for ferritin?

Low b12 and low folate can lead to enlarged red blood cells. Low iron can lead to small red blood cells. Someone with both low B12 and/or low folate plus low iron may have normal MCV levels because effects of low iron on red blood cells can mask effect of low b12/low folate.

Are you in UK?

If yes, I'd suggest reading the BSH Cobalamin and Folate Guidelines.

Flowchart above makes it clear that in UK , patients who are symptomatic for b12 deficinecy should have an IFA (Intrinsic Factor Antibody) test and start initial B12 treatment. This applies whether B12 is low or within range. IFA test can helpt to diagbnose PA but is not always reliable. It's still possible to have PA even if IFA result negative.

BMJ b12 article

5th summary point may be relevant?

Are you symptomatic for b12 deficiency?

pernicious-anaemia-society.... see PAS checklist

What to do next?

I am not a medic just a person who has struggled to get a diagnosis.

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Do you have a result for calcium and parathyroid (PTH) . Sounds like you may be an undxed Coeliac which case..are you 100% GF? No crumbs or eating out ? Do you share a kitchen with a gluten eater? I am a probable coeliac and have not been able to eat out in years.... due to crumbs of cross contaminated food. Symptoms are like you are getting now...if I eat out and get a contaminated meal...

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Hi Jane, I'm very careful. My kids are GF and my husband almost is!

I do not think I had those tests.

Thanks for the replies. I feel at a bit of a crossroads. I really thought the tests would give me some clues. Perhaps I need to educate myself better first. ..With sleepybunnys links to decide next steps.

I could go back to my dr but I need an intelligent case to put if I want more tests, I haven't heard of some of the ones suggested here.

I'm feeling worn down and impatient I just want to get on with my life especially after these losses in the family; also I have little children too and can't afford to be laid low. I just feel like experimenting with some vitamins to see if my pains, fatigue and the mild intermittent neuropathy ease off. I realise it might jeopardise a diagnosis down the road but I don't know if I am up for a drawn out wrangle with my GP...Or I guess I can run some private tests now before I start supplementation in earnest.

I need to have a think. I appreciate the input from each and every person 😊


B12 books

"What You Need to Know About Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper. Martyn is the chair of PAS. Book is up to date with current UK guidelines. He has written two other books about PA and B12.

"Living with Pernicious anaemia and Vitamin b12 Deficiency" by Martyn Hooper. I found this helpful as it had several case studies in it. When i looked at teh case studies , some of teh people had similare xperiences to myself eg being diagnosed with ME/CFS.

"Could it Be b12" by Sally Pacholok and JJ. Stuart (USA authors)

I notice from your results that your MCH is not far off the top of the range. High MCH can be associated with B12 deficiency.


Sedgie, although B12 is far from clear from the serum test - and getting towards the unlikely end of the spectrum that doesn't mean that it couldn't be B12.

You seem to have ruled out thyroid and vitamin D. If you continue ruling things out then that means B12 goes back up the list again and may be the only viable option - and that may be the way to tackle it with your GP - get all the information you can on the limitations of serum B12 test .... and ask for some tests that look at other markers for B12 - which probably means MMA (or possibly homocysteine).

Has iron deficiency been totally ruled out? As I understand it the ranges for people with thyroid problems start a bit higher than those for people without thyroid and ferritin is quite a good guide to iron levels - though not conclusive.

The mix of an iron deficiency and a B12/folate deficiency would leave interpreting situation from cell size rather cloudy - not sure if I've said that you to or not - and you'd probably look as if you were more towards the microcytic end of things than the macrocytic or leave things in the middle.

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Thank you. I am really struggling to collect my thoughts. I've spoken to my husband and he wants me to speak to my GP again. I'll see him Friday and ask where we go next. To be fair he ran about 30 tests so he is trying to find the root cause.

I fee particularly unwell today. Nausea and things...very achey and wiped out, light headiest and this pulsing in my feet and slight numb feeling. Do you have good days and bad periods with the B12 thing? Or is it constantly unwell and a decline. This is why I thought thyroid. It's in the family and I sometimes feel pretty good ...


sorry to hear that you are feeling so rough.

What you describe sounds more as if you have an infection than anything directly to do with B12 - being B12 deficient does lower the immune system and leave you more susceptible to infections.

I think the thing with evaluating B12 is to make sure that your GP is aware of all the problems interpreting the B12 serum test and that it can't really be taken as conclusive just on a single value on its own, that macrocytosis isn't always present and that there are some other tests - MMA and possibly homocysteine that might help clarify if not done already.

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Thank you I will try and convey this. I think I did have a bug or gastric reaction to something I ate.

I would be happy to walk away from my GP and work hard on diet and nutrition and some measured supplementation as this helped me last yr with my chronic headaches.

Its this buzzing and slight numbness and stiffness in my limbs that I'm unhappy about as I haven't had it to this extent before. I hope I can get somewhere. If my GP is not going to send me for new tests can I order your suggested ones myself privately, is the active B12 another I should think about?

Thanks for all the messages 😊


active B12 is a bit better than serum B12 as it looks at the amount of B12 in your blood that is bound to a protein that facilitates transfer from blood to cell - rather than to a protein that facilitates storage in the liver - however, it's still only measuring the amount of B12 in your blood rather than what is happening with the B12 once it is in your cells which is what MMA and homocysteine are looking at.

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Ok I get it now. Thank you.

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Just in case I anyone is still there. I'm off to see my GP shortly and I've tried to add my other blood tests in my first post.

From what I can see I don't think iron or mma or homocysteine has been done. I'll see if I can convey this...eek!


Pls don't worry I'm back from the GP. He isn't inclined to run more tests at this time. I'm on my own but it's ok. I'll see how I go. Thanks for all of the help.


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