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Pernicious Anaemia Society
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MCV 95.3 fL and MCH level 32.2 pg (27-32) but gp refusing trial of b12 injections


Would very much appreciate any advice and links about high MCV and MCH to take to gp. Have experienced fatigue, swimming head, severe balance problems and shortness of breath for a year. Serum b12 was 420 then 518 after eating liver regularly. Had been taking methyl b12 but made balance worse, hydroxocobalamin sublinguals have very recently improved balance problem so I can function again but shortness of breath and fatigue still there.

Only read last night about MCV and MCH possibly indicating b12 deficiency if they are higher but can't find anything on internet that mentions actual readings. Mine are 95.3 (80-100) and 32.2 (27 - 32).

Folate is good at 19 but ferritin 37 so I've started on iron supplements. Vitamin D 70 (30-300).

Would prefer an actual diagnosis and injections through surgery than to go it alone. GP refused to start trial of injections based on my balance issue as b12 had increased from previous blood test. Have also considered asking to be referred to either haemotologist or gastroenterologist. Has anyone had success with either?

Thanks in advance.

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I've assumed you're in UK.

"hydroxocobalamin sublinguals have very recently improved balance problem so I can function again "

To my mind if all other diagnostic possibilities have been excluded and B12 treatment improves symptoms, there is a strong possibility of B12 deficiency. I am not medically trained though.

Taking B12 supplements can make it difficult to get a diagnosis if a person is B12 deficient.

Link about what to do next if B12 deficiency is suspected


It's possible to be symptomatic even if B12 is within normal range, See links underneath.

BMJ B12 article


BSH Cobalamin and Folate Guidelines


Flowchart from BSH Cobalamin and Folate Guidelines


b12deficiency.info/b12-writ... See Point 5 which mentions functional B12 deficiency where there is plenty of b12 in blood but it's not getting into the cells.

Misconceptions about B12 deficiency


I was highly symptomatic for B12 deficiency with numerous neuro symptoms with B12 results between 300 -400 ng.

B12 books

"What You Need to Know About Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Martyn Hooper is the chair of PAS (Pernicious Anaemia Society). Book is up to date with UK B12 guidelines.

"Living with Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Has several case studies.

"Could it Be B12; An Epidemic of Misdiagnoses" by Sally Pacholok and JJ. Stuart (USA authors)

Very comprehensive book about B12 deficiency with lots of case studies.

Blood test links

Have you had an intrinsic Factor Antibody test?

This can help to diagnose PA but is not always reliable. It is still possible to have PA even if IFA test result is negative/normal range. IFA test may give false result if taken close to a B12 injection. Think doctors suggest leaving between 2 days and 2 weeks after a B12 injection before having IFA test.





B12 Deficiency Symptoms

pernicious-anaemia-society.... See Checklist PDF on right of page.



PAS (Pernicious Anaemia Society)


PAS tel no +44 (0)1656 769 717

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Hi Sleepybunny,

Thanks so much for your reply and all the links. My plan of action is to take my husband along to next gp appointment for moral support. Also have a spirometry test booked in for Tuesday so hoping that will nudge the doctor to realising things are far from right and taking some action.

It's a shame that as I've been taking sublinguals that further tests will be inaccurate but needed to get some quality of life back and could only manage two months "cold turkey" while I held out for the blood test. I wish that I knew about the other tests including MMA but like others, I put too much faith in the mainstream medical profession but of course GPs know so little about B12.

I hope your recovery wasn't too long and that you're well on the road to recovery.



Pleased to hear that your husband is going with you.

Having a witness can be useful and my experience is that doctors are sometimes kinder when another person is present. Another person can take notes although this may irritate some GPs.

I would suggest that it's worthwhile that anyone going with you reads up about B12, especially the UK documents I listed.

There is also a useful summary of mainly B12 documents in third pinned post which I think is worth looking at before your appt and lots of other B12 info in pinned posts.

If you suspect PA (Pernicious Anaemia) is a possibility, might be worth joining and speaking to PAS before appt. PAS should be able to point you to useful info. PAS contact details in post above.

Risk factors for PA and B12 deficiency




Family History

Do you have any family history of PA, B12 deficiency or other auto-immune conditions. The presence of auto-immune conditions in family can increase chances of developing one. PA is an auto-immune condition.

If there is family history is GP aware of it?

I was very symptomatic with multiple neuro symptoms for many years, was unable to get NHS B12 treatment and in end had to treat myself. Some of my neuro symptoms disappeared when I started B12.

Neuro Symptoms

Do you have any neuro symptoms eg tingling, pins and needles, memory issues, balance problems, tinnitus plus other possible neuro symptoms? I think it is important to make sure GP is aware of any neuro symptoms.

Have a look at lists of B12 deficiency symptoms in post above. I ticked all my symptoms on PAS checklist and gave a copy to my GPs.

My personal opinion is that GPs are sometimes more likely to take notice of questions asked in a letter rather than in an appt. See link about writing letters in above post.

If yes to neuro symptoms, have you seen a neurologist?

If you have a neurology appt, I would suggest reading up about proprioception problems and romberg test before appt. People with b12 deficiency sometimes have proprioception problems (loss of awareness of body in space).One test for proprioception problems is walking heel to toe with eyes closed. It's vital that these tests are done under supervision of a doctor.

I saw several neurologists and only one, in my personal opinion, had a reasonable understanding of b12 deficiency. As far as I remember, none of them tested me for proprioception problems.

Hope your GP is aware of neuro consequences of B12 deficiency.


Thyroid and Coeliac disease

The symptoms of thyroid disease can overlap with those of b12 deficiency. There is a Thyroid UK forum on HU, may be worth posting thyroid results on there.


Coeliac disease can lead to B12 deficiency due to its affect on the gut.



I gave the following to my GPs.....

1) Copy of BSH Cobalamin and Folate Guidelines

2) Copy of Martyn Hooper's book ""What You Need to Know About Pernicious Anaemia and Vitamin B12 Deficiency"

3) Copy of PAS symptoms checklist with all my symptoms ticked.

I am not medically trained, just someone who has struggled to get a diagnosis.

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Hi Sleepybunny,

You're very kind to be taking time out again to advise me, thank you.

When I visited the first GP in April, I had balance problems, mouth sores and fatigue. Balance has been my only neuro symptom.My b12 came back at 412 so he was not considering b12 deficiency. He seemed to focus more on the blood test showing that I was going through the menopause and thought the balance problem was caused by that. He then dismissed the mouth sores, thinking that was just unique to me. Shocking now when I look back!

Next GP thought it was more an ear related problem so referred me to the vestibular clinic within ENT. Nothing found and ENT consultant thought it might be stress related (high stress events in last year). Passed me back to third GP who was happy to retest b12 when I requested that. She did want to refer me to neuro but changed her mind at second appnt once letter back from ENT.

In the meantime, I had researched possible causes of the balance problem and b12 kept on cropping up. Blood tests then showed 520 for b12 so third GP refused to give trial injections. She believed that ENT had ruled out any neurological cause/problem so in effect had checked me for vestibular and neuro problems. I showed her how bad my walking and balance was but she dismissed this, concentrating more on the shortness of breath that had become worse after I had stopped taking methyl b12 sypplements. Had wanted to come off of supplements before further blood tests. Managed two months without and ate more b12 foods including liver which probably explains why level went up.

Fortunately I had spoken to PA society the afternoon of being refused the injections. They told me that my balance was a neuro symptom and of course needed to be treated sooner than later. Also that day, I started on hydroxy sublinguals from seeking health and to my great relief, within hours my balance had improved, along with the swimming head sensation. The tablets have helped the SOB but I am still very tired, not managing to do basic housework tasks but walking upstairs is now easier since the tablets.

Because I had such a breakthrough, plus so many other things going on, I haven't gone back to the GP again but did sent a letter to the GP enclosing the guidelines for diagnosing PA that the PA society had directed me to. Because I became exasperated at the doctors appointment, she said that she would speak to other doctors in the practise to see if anyone else had a similar patient with potential b12 problems. I though that the guidelines would help. Nothing heard since appointment on 18th October.

I now want to go back with all this information that you have given me, the bmj, stichting x2 and PAS checklist will be particularly useful. I'll also post them to the GP before the appointment. Hopefully she has received my previous letter. ( I also need to send a letter with enclosures to ENT!)

I don't have anyone in the family with PA or similar, only an aunt with hypothyroidism. My TSH was 4.13 so interesting that you mention thyroid, I need to check this out too. I've also signed up to a b12 Facebook page which is where I read about the high mcv indicating b12 deficiency. I'm pleased that I asked for my blood results last month.

At least my symptoms are a lot better but I want to start injections to prevent any permanent damage to my balance system. Hopefully the SOB will ease in time particularly now I'm on iron tablets to support the b12 sublinguals.

Take care and thanks again.

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Hi - your TSH indicates the Thyroid is struggling. As you know the Thyroid Stimulating Hormone comes from the Pituitary Gland and tells your thyroid to produce T4. So you also need the FT4 and FT3 reading for more detail. Also test the anti-bodies TPO & Tg - to check for Hashimotos. T4 is a storage hormone and does little in the body - and so you need to know if this hormone is converting into T3 - the ACTIVE thyroid hormone needed in every cell of your body. Rarely tested in the NHS - what a scandal.

Sadly the NHS rarely check beyond the TSH and 1000's remain unwell. I am usually on the Thyroid UK Forum where there are 70,000 members struggling with the inadequate testing and treatment.

If you are able to have Home Testing - a kit can be sent to your home and so the CORRECT testing can be done and results sent to you be e-mail.


Happy to help :-)

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Hi Marz,

Sorry, I missed you reply earlier. Thanks so much for your reply. I remember feeling cold this spring which wasn't like me.

Looking at older levels from my medical records that I've just acquired, TSH was 3.15 in May, 4.95 Feb 2016 and 2.54 in aug 2015. My folate level has been high in the past but good now at 19 so I wonder if along with low ferritin and underlying b12d, it's regularly affected the TSH?

As I'm learning, it also seems to be all a balancing act.

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Yes the TSH is fluctuating which can be caused by a few things. Were the tests done after fasting and all at the same time of day ? Also when you have Hashimotos the results can vary. This why the TSH test tells you so little and why the tests I listed above for you are important for the complete picture.

On the link I posted above you can read up on the Thyroid and the Signs & Symptoms of Hypothyroidism - all 300 of them 😊 You may find your symptoms there too !

Hashimotos is the most common thyroid issue globally so without the anti-bodies being tested - how will you know.

I have Hashimotos and a B12 issue 😊

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Hi Marz,

The aug 15 2.54 was non fasting and all the rest fasting. Very interesting that the fluctuations could be down to Hashimotos. Definitely need to pursue the hypothyroidism and the b12. Thanks again.

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Ah that answers the difference - the TSH reduces after eating. Hence for those wanting a diagnosis it is advised to fast :-)

The upper figure for TSH in the US was reduced to 3.0 back in 2003 - and it is commonly regarded that any figure over 2.5 is on the way to being Hypo. Of course the more important figures would confirm - the FT4 and FT3. FT3 rarely tested in the NHS and yet it is the MOST important one. They Test the anti-body TPO but not the Tg. I have given you the link to Private Home Testing Kits in my earlier post.

It is always good to rule out Hashimotos or a Thyroid issue as it can be the cause of so many symptoms ....

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Thanks Marz. Unfortunately the private home testing kit is above my budget at mo, not to say you can't skimp on your health but various things high stress events have happened this year but hoping things will be more stable soon.

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Yes I do understand. I live in Crete so testing is more available and cheaper.

Maybe you can persuade your GP to do more than the TSH 😊

Hope you soon feel better ...


Thanks Marz,

I'm having the spirometry test done this afternoon so will ask nurse if she knows who might be more b12 and thyroid aware.

Take care.

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Hope all went well yesterday 😊

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Thanks Marz,

It transpires that the GP was testing for asthma and received confirmation today that all was ok (no surprise as they were barking up the wrong tree but good to check I suppose even in the absence of a cough). ENT have contacted me after GP re-referred me to them, will phone them back tomorrow.

I hope you've been having good days.

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Hi again,

"My TSH was 4.13 so interesting that you mention thyroid, I need to check this out too"

Marz who posts on this forum knows about thyroid problems, might be worth searching for her posts.

In UK, GPs often only ask for TSH test but other thyroid tests are needed to give a full picture of thyroid function. Think it's worth posting that result on Thyroid UK forum on HU.



"When I visited the first GP in April, I had balance problems, mouth sores and fatigue"

Balance problems are a neuro issue so my understanding (I'm not medically trained) is that in UK, a person who is symptomatic for B12 deficiency with neuro issues should have a B12 loading jab every other day for as long as symptoms improve (could mean loading jabs for weeks even months) then it's a B12 jab every 2 months.

You are entitled to ask for a referral to a neurologist although GP does not have to refer you. I sometimes used to offer to pay for referrals if GPs reluctant to refer. I also made formal polite requests for referrals in letters to GP. My understanding is that letters to GPs are filed in medical notes so are a permanent record of issues raised.

A word of warning.....some GPs find assertive patients difficult to deal with and there is the possibility of the GP/patient relationship deteriorating.

This treatment info is in BNF Chapter 9 Section 1.2, GP will probably have a copy on desk. It's also in BSH Cobalamin and Folate Guidelines, quarter through guidelines. BNF suggests advice from a haematologist should be sought for someone who is symptomatic for B12 deficiency with neuro symptoms.

The BMJ B12 article emphasises the importance of treating people who are symptomatic for B12 deficiency to prevent neuro damage, this applies whether B12 is low or within range.

The flowchart from BSH Cobalamin and Folate Guidelines also makes it clear that people who are symptomatic for B12 deficiency should have an Intrinsic Factor Antibody test and start initial B12 treatment. This applies whether B12 is low or within range.

IFA test can help to diagnose PA but test is not always reliable and it is still possible to have PA even if IFA test result is negative/normal range. Flowchart mentions Antibody Negative PA.

Is your GP aware of the consequences of untreated or undertreated B12 deficiency?

Some forum members have given GPs info on SACD, sub acute combined degeneration of the spinal cord.

PAS members can access an article about SACD from PAS website.


Blog post that mentions SACD


PAS news item about neuro consequences of PA


If your GP shows some interest, there is a section on PAS website for health professionals. They can join PAS as associate members for free.


Letters to GP about B12 deficiency


Point 1 in link about writing letters is about under treatment of neuro symptoms.

Point 5 is about being symptomatic with an in range B12 result.

Good luck.

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Thanks Sleepybunny,

It definitely looks like I need to do a letter and send in these articles before the appointment.

Have just received my medical records from last 3 years (changing life insurance provider) and my RBC was under range at 3.7 and ferritin 13 two years ago. MCV also above range. They did nothing about it or did not notice, even though I have periodically mentioned feeling tired all the time for years. No wonder I was running on empty!

Take care.


Ferritin needs to be mid-range for your thyroid hormones to work effectively in the body. Hashimotos trashes absorption .....

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