Pernicious Anaemia Society
14,660 members10,436 posts

Does the NHS measure holotranscobalamin?

Hi, I've been looking into tests for Functional B12 Deficiency. I know the NHS will measure MMA, and maybe Homocysteine if you beg, but does anyone know if the NHS will measure holotranscobalamin for you, or is it considered too woo-woo or unnecessary? Anyone ever had theirs measured? If so, did you have it done on the NHS, and on what grounds?

Any insight, as usual, most gratefully accepted - I need to be armed for seeing my doc. Ta!

20 Replies

holo-T is known as active B12 in the UK. Some areas of nhs do it but don't think all do.


Thanks, Gambit. Will it be affected by me having B12 injections, do you think? More importantly, if I had functional deficiency would Active B12 automatically be low anyway?


Functional B12 deficiency means that not enough B12 is doing its job inside the cell, despite high serum levels. Having too little holoTC is one reason, there are other possibilities which a holoTC test wouldn't show up.

MMA and tHcys tests should show up any functional deficiency, no matter what the cause.


Thanks fbirder, I'll stick to the MMA combo and keep it simple!


one of the possible reasons for functional B12 deficiency is a reaction that actually means that cobalamin stays in the blood rather than passing through to cells so also possible that active B12 would be high.

Active B12 isn't really the test to do for functional B12 deficiency - MMA and homocysteine are better guides to what is actually going on in the cell.


Thanks, Gambit, I suspected that. Absolutely zero point in giving myself an extra fight to have Active B12 measured if it might only muddy up the waters anyway. I'll stick to MMA & Homocysteine. One fight at a time.


I was diagnosed by my GP with Functional B12 deficiency in October last year, confirmed by St Thomas' by high MMA results. I am now seeing a haematologist, who is having my blood sent to genetics lab for further tests, to find a cause for high MMA results (now higher than previously) although active B12 was within normal range. I am also having an MRI brain scan and nerve testing next week from neurologist. This has all been NHS treatment, initiated because my GP remembered that she had a patient 10 years ago with the same condition, knew she would be unlikely to remember "Methylmalonic Acid" and so kept notes !

Solely because symptoms remained even after standard B12 treatment , then symptoms still not gone after 6 months of 2 injections a week and B12 in blood more than 2000 but MMA high, I was passed on to haematology and neurology for further investigation.

You need MMA tested, Gambit is absolutely right, and a normal active B12 result might well hamper your chances of getting it. Best of luck, Chancery


Thank you, Cheryl, that's really helpful. Can I ask what your symptoms were and if it was your doctor that did the MMA test? Also, was it a blood serum test or the urine version?


GP tried to get the MMA test done locally without success, so sent blood to St Thomas' to get her diagnosis confirmed. It was blood serum. I started as being just under range with B12 (blood test) but after loading injections and the first two 3-monthly injections, I got much worse although blood by then swimming in B12: that was when she thought that Functional B12 deficiency was the problem and sent blood samples off.

Symptoms were hair loss, splits at corner of mouth and sore mouth and tongue, left-hand groin pain, lower back pain, tingling hands and feet, exhaustion, infection-prone and poor healing, but much much worse were the neuro problems: irritation, irrational thought, mood changes, angry outbursts and crying, cognitive problems, attention problems and sensory overload especially problems with noise, fast movements, bright lights. Daily diarrhoea has been a constant nuisance too.

Don't think I've ever had homocysteine test.

Hope this is of some help, Chancery


Thanks, Cheryl, very helpful indeed. My symptoms don't remotely resemble yours so maybe I'm barking up the wrong tree entirely, but then people do express issues differently by way of symptoms. Plus I may not have nearly as severe a problem as yours since B12 definitely helped me, it just doesn't seem to be helping me enough! But the B12 certainly never made things worse - I wonder if that's a defining characteristic? Because I know they do recommend giving people with Functional Deficiency more injections so I assume it does work at some point! Did your doc step your injections up from 2 a week? How often are you having them now? Also, did you have some other kind of issue showing, like anaemia, or were you otherwise 'normal' as far as blood tests (or anything else for that matter) were concerned?

My apologies for all the questions but it's exceptionally helpful to speak to someone who actually has the condition and is having it treated! I appreciate all your help.


Don't apologise, Chancery , no problem at all. Glad to be of some help.

Re. symptoms: mine are probably not very 'normal' in terms of what a GP is likely to look for and relate to B12 deficiency. Just check some of the lists out on google: the more "medical" ones for GPs identification purposes are very brief, the ones written by and for B12 deficiency sufferers are huge (and often ignored by GPs) and varied. Probably why so many of us constantly get offered antidepressants before vitamins !

Many people get very bad headaches for example, or have trouble walking/ tend to drop things because they cannot feel their feet on the ground or the item in their hand. I am lucky not to have experienced these symptoms. There are probably plenty of others that I don't get: pity the poor person who has the lot !

Having B12 injections, even at the frequency of 2 a week for 6 months, did not turn out to be a miraculous recovery story for me either. I did not get worse and small slow improvements to my least-worrying symptoms (hair loss and poor quality, splits at corners of mouth) meant that outwardly, all was looking well - to GPs and nurses. Friends and family are not so easily convinced, and notice more. I felt quite disheartened because I was expecting more to happen- and still hoping to go back to work at some point. I think when I told the GP this, she was worried and passed me on to haematologist and neurologist, and was advised to lower frequency- a lot !

I am now on 1 a month, and not at all as bad as when I was on 1 every 3 months, but still got symptoms, and still gets worse about 16 days in- so perhaps if I could be 'allowed' more, I would have fortnightly injections. If I was self-injecting, I would probably start with 1 every other day, since I never had the luxury of getting the injections as per guidelines (and don't know of anyone who has either)- just to see if that does the trick before reducing frequency to find optimum level. So nothing has yet disappeared in terms of existing symptoms, but certainly moods fluctuate less, cognitive ability not so bad- difficult after all this time to be sure this is improvement and not just situation avoidance. Life is somewhat pared down.

I first went to GP because I was very tired, had left-hand groin pain and diarrhoea every day. I had a lot of blood tests but was referred to bowel people first. The only thing apart from B12 just under range (at that time) was ferritin and folate at low end of normal range. I only realised how many other issues I had (and put down to other things or completely ignored) when some started to improve after loading, from looking up 'B12 deficiency', reading Martyn Hooper's book and seeing me so clearly I cried, and joining Pernicious Anaemia Society. I've had sore and split mouth for about 9 or 10 years- who'd think to go to the GP with that? And if even if you did, what GP would recognise this as a possible symptom of B12 deficiency?

Write all the symptoms down, yes even the ones that sound petty because it all helps to build a picture. Keep monitoring them in diary or chart. Work out the ones that are good response indicators: visibly come and go easily depending on B12 levels. Use these as a guide to work out what you need. Not easy to find patterns that are regular enough, but colour-coded charts simplify things over time.

Usually, MMA and homocysteine levels would be expected to normalise after a very short time of having B12 injections- mine was never tested before B12 injections, but firstly 7 or 8 months later, then again recently (April). High, then higher. Not massively high but not right, hence the genetic testing. All other possibilities (renal problems etc) ruled out already.

This has turned out to be a very long reply, even for me, but I wouldn't want anyone else to go through years of this process. I wish you well, chancery, let us know what happens next.


Thank you, thank, thank you - most cheering after a horrific doctor's appointment to ask for MMA & Homocysteine testing today.

First she'd never heard of Functional Deficiency and did the usual doctor's trick of jumping in before I was about two minutes into my spiel. They actually measured this habit and I think they said it was something like a minute and a half before doctor's interrupt their patients - so I suppose she was on form!

She told me I couldn't possibly have a B12 issue because I get monthly injections so I had to describe Functional Deficiency to her and point out the whole issue was high blood serum didn't mean anything as it isn't getting to the cells. That didn't make her happy. She'd never heard of the testing, didn't know if I could have it, and said she'd have to talk to the biochemist. I love the fact that a biochemist ultimately decides if I get treatment or not, even although he's never met me, knows nothing about my condition and isn't, as far as I know, medically trained. Mind you, my doctor IS medically trained and she didn't have a clue, so maybe a biochemist is a step up.

I had taken in a list of 37 symptoms, chiefly because I'm tired of lots of the 'back up' material never getting aired. I reassured her I didn't expect her to read it right then but she did glance at it (another valuable minute gone) and told me, like they ALWAYS do, that these symptoms could be caused by anything and they might not be connected and blah, blah, blah. They might as well just say 'You patients are all conspiracy theorists'. I'd feel more reassured that she knew better if she'd actually heard of the condition in the first place.

But it didn't end there. I asked her for a 'just in case' prescription of Carbamazepine for my Trigeminal Neuralgia and she refused it on the grounds that I once (in 18 months) had a hospital visit because of low blood sodium. She then told me there were other treatments and I might have a fit if she let me have it (where was that worry during the 18 months they were doling it out to me?), and, and, and. I had the most horrible feeling it was all about ego because she hadn't been able to control the rest of the appointment and I'd brought in a made-up and highly unlikely condition just to shame her.

I get so sick of taking care of doctor's very precarious egos, and even more sick of them bolstering themselves up at our expense. I mean, refusing drugs for the condition known as 'the suicide disease' because of the severity of its pain because she feels threatened in some way? There's no words.

Anyway, now I have to wait for a phone call from her to see if I can be tested. I don't know what I'll do if they refuse me. If I do get the testing, probably after having to write a formal complaint, it will be absolutely normal and I'll look like a neurotic trouble-making idiot.

Thank you for listening to my venting and thank you for the reassurance that you didn't look like an obvious B12 victim either - I don't feel so crazy now that I've seen some similarities between our histories. You've been super-lucky, I think, that the other poor woman went ahead of you because then your doctor spotted the connection and guessed what she was looking at. Although you probably don't feel lucky!

Incidentally, I too get a threshold with B12 injections. It used to be about the three week mark before my mouth got 'sparky' again, but then I was getting it just a fortnight in, and then after that it started to feel like it wasn't doing as much for me full-stop, so there definitely is a feeling of knowing where your level is. Right now I'd say I could do with some loading doses then I'd guess about once a week for a while. Completely unscientific but that's how it feels.

Would you mind if I got in touch if I have any more questions or my village idiot of a doctor throws me a curve ball? It's a comfort just to have someone else who's gone ahead of you. I promise not to b*tch about my doctor again - she just made me so damn angry! Thanks again.


Me again, I've just seen another discussion of yours and saw this: "Showed yesterday's haematologist the Turner and Talbot paper: she pointed out the date (2009 I think ?) and I said no-one's done anything since."

Do you have a copy of the full paper, or even a link to it? I'd desperately love to see this but I've only been able to find a bought version at £27, which is just too expensive for me. Please let me know if you'd like me to do your laundry or paint your house or whatever else you might desire in exchange and I will cheerfully do it (providing, obviously, that it comes in at under £27!)

I'm going to look through all your posts, not to be all stalkery (it sounds stalkery just saying that, so that was a pointless justification) but because I hope to glean lots of useful nuggets. Thanks once more and let me know if you need anything weeded or mended.


Hi Chancery - no you don't sound like a stalker, just a bit desperate for something to go right for you and we all recognise that feeling. Also sometimes think I might have imagined it all or that I am cured- even now, if I have one rare good morning, by lunchtime I'm feeling guilty about not being at work.

It's hard to find anyone else with this condition, or (sadly) a GP that knows about it. That is where I was lucky- she knew about it, had treated it previously, remembered it and diagnosed it in me before I'd even got my head around having a B12 deficiency that did not seem to respond to treatment as well as Pernicious Anaemia would have. And even she had started off by saying "I think there are a number of issues going on here" because the symptoms I was presenting with did not fit in with her understanding of B12 deficiency. Also thanks to the poor patient who came before me and hope she is thriving 10 years later. Wonder what treatment she is on re frequency or if she resorted to SI?

Talbot and Turner paper, although disappointing to evidence-hungry people like you and I, actually names it and rather vaguely states that we need more injections than others do, which is hardly a guideline that a nervous GP would accept but they are at least medical folk. I don't have a computer and so I use the library one. I don't either have the skills to send you a copy of the report- unless by post of course, which I'm more than willing to do. I am almost certain that Foggyme or Gambit62 gave me a link to download, so hopefully they will be better able to help with this. They both have a sound understanding of this condition and have given me support throughout.

If you have read some of my previous posts, you might be aware that I am also vegetarian, although I really don't believe that 35+ years later, diet has anything to do with my condition. I have spent my adult life as a carpenter and joiner and teaching woodwork including the use of industrial machinery so expected a level of fitness (that has now disappeared). There is no reason, if you eat eggs and cheese, why this would be the cause, and I cannot find any evidence to support this although it is often the case that in research papers and medical reports, particularly from America, they seem unable to distinguish between vegans (who do need to supplement) and vegetarians (who don't necessarily) - and have seen "strict vegetarians" used as if it is valid terminology. I can only assume that the research is carried out by meat-eaters who cannot differentiate. It has caused me more "blame yourself" problems with consultants than being an ex-smoker has !

Feel free to rant about GPs to me if you like. Even I've done it and I really like my doctor. I read up a bit about your Trigeminal Neuralgia: that alone must be awfully difficult to deal with. Hope you are not disappointed by Talbot and Turner report. I'm going to search for the link, see if I can find it, but hopefully, the administrators mentioned will get it to you first - keep in touch okay ?


Me again, Chancery - while you are waiting re. Talbot and Turner, have a look at this:, under the heading Differential Diagnosis, there is a bit about functional B12 deficiency that at least proves it exists and is dangerous if untreated (undertreated?) Perhaps enough to start with ?


Thank you, Cheryl, I actually managed to get a copy of the Talbot paper through finding a link in your posts - so the stalking paid off!

It was both reassuring and depressing to see that 2 years (I think?) after you were diagnosed you're still trying to get effective treatment, and that was with a first-class diagnosis from a specialist hospital dept, no less. It was disturbing to see your haematologist (again, I think - sorry, I read your posts REALLY late at night and still full of adrenalin from my doc's visit so it's a jumble of data) trying to shoehorn your condition into another condition entirely, with Q10 (available at a health store near you!) and Riboflavin, was it?, as recommended treatment. WTF? Why has your perfectly sound diagnosis been written out the picture, for the love of God?

Like I say, reassuring because I'm not alone in the lunatic fringe but also depressing that a sound diagnosis is not anywhere near the end of the line.

But, good news, I got a phone call this morning and I'm getting the tests! I was gobsmacked, especially as they are giving me both. I still can't believe it.

Now I'm worried though that as I've just had an injection it will skew the results. I've made an appointment for 2 weeks time to have the blood/urine taken, but is that enough time? Should I change it to right before my next injection? It seems safest but on the other hand if I actually do have Functional deficiency the results should be elevated regardless of injections. Yours was and you were on 2 injections a week - is that right?

I like to give myself neurotic things to worry about. I think it's because there's always so much riding on one test. You never get to redo it or say, 'Sorry, might my injection have distorted the results?'. Its always a first and final so you end up in paralysing doubt about the damn thing. Any advice you can offer about whether 2 weeks will be fine or I should go for just before my next injection most gratefully accepted.

1 like

Wow! Wonder what changed your GP's mind? Bet she googled it after you left, because she got caught left-footed and wanted some ammunition to prove you wrong for next time - which backfired in a Teresa May kind of a way ! Or is that total paranoia ?

[ And, having brought her up, why do they keep calling her "Mrs May" ? ]

Now, back to the really important issue of the day:

Well done for getting the Talbot and Turner report ; I tried to find that link and couldn't. Computers really not my thing, never been much of a sitting-down type person. Do you see what I mean about the report being a little vague on treatment ? Still, it's something. Despite U-turn (sorry, can't seem to help it ) by your GP, keep this report on you just in case. If you get as far as haematology, they are unlikely to be aware of it's existence, surprisingly.

It was the neurologist who decided it could be Q10 and, yes, riboflavin I think- or another B vitamin that isn't B12. Pick one. It's only B12 they are afraid of ; too complex ? At least the neurologist admitted he did not know much about B12, but that I had a sound case (albeit delivered in a very unsound way!) which I need to put to the haematologist - shame he did not then put that in his letter to the haematologist, so a bit unsupportive, cowardly and passing the buck, but not a liar -so perhaps worth the 5 month wait. At least that only cost me in energy.......

The 2 haematologists that I have seen believe that B12 is highly addictive, and that it's dangerous in large doses: they've got the mice to prove it apparently- but can't produce the research report, not even if you ask 3 times. I really believed that was the magic number, and I did say "please" which everyone knows is the magic word. Still nothing. Ah well.

Just warning you, Chancery. You could be luckier of course, but it's as well to know. I really did expect more from the experts, and so did my GP, who passed me on to them because she felt ill-equipped to deal with a worsening condition. Even she laughed when I told her that my brain malfunction was believed to be due to smoking for so many years that it became oxygen-starved (!) Haematologists don't like vegetarians or ex-smokers, it seems. Lucky I'm only drinking 9 units a week (that's sharing a bottle of wine at weekends with dinner, by the way) or she might have had me put down there and then !

Despite my feelings of abandonment when my injections were reduced from 2 a week to 1 a month fairly recently, the GP was actually doing me a favour: it meant that when the bloods were taken at haematology, my last injection had been about 3 weeks prior to this first appointment- one of the tests being an MMA retest. I too worried about skewing, but this one came back a bit higher than the one before. This surprised me, because the first one was taken when on 1 injection every 3 months and felt like I was plummeting.

Sad thing to rejoice about perhaps, but otherwise I may well have been dismissed because I haven't got anything else abnormal in blood to show them - and that is all they measure!!

So here we are then: diagnosed with Functional B12 deficiency by GP, confirmed by St Thomas' due to high MMA reading (blood) in October- now waiting for brain scan and electrical nerve-testing next week, and results of blood tests from genetics lab which could take a couple of months - all wrapped up and delivered to me by a haematologist who believes B12 to be both highly addictive and carcinogenic. Nightmare scenario.

Amenable GP meanwhile, having handed over the controls, has to now go through THIS person to up my dose from 1 a 2 chances, Chancery: slim or fat !

Finally, here's some good news: got signed off this morning from physio - keyhole surgery on shoulder a success: mobility and strength returning. So healing rate (bone, muscle, rotator cuff) also much improved !

I get what you're saying about the one-shot chance at getting what you want. To counter this feeling of vulnerability, I'm always reminding myself that this is a vitamin after all, widely and (almost) freely available elsewhere in the world, and we can control our own destinies should common-sense ultimately fail to prevail !


TOTALLY Googled it, Cheryl. Damn right. But hey, all praise due to her, she could easily have taken her wounded ego and only paid lip service to asking, but she obviously didn't. She got The Biochemist out his cupboard and twisted his arm. Unless, of course, The Biochemist is actually the hero of this piece and he told her off and said something like "This woman has TN AND numbness in her leg and face and you haven't checked her MMA yet?". Maybe she was shamed into doing it! No, I am giving her the benefit of the doubt - she stepped up. I feel guilty now for being so mad at her, although I still don't see why it always has to be a big drama and begging to get these things.

You made me laugh tout loud with your mice. Believe it or not I had an opposite version of that with Capuchin Monkeys. When I did my thesis (and it was a thesis) for my doc, the most recent paper I could find for B12 treatment & TN was 2011 (I suppose that's better than Talbot's 2009) where some giddy Australians had tested it on Capuchin monkeys in whom they had - inhumanely in my opinion, but I am very grateful - induced TN. When I showed this gem to my doc to prove that people did still research B12 in TN and it wasn't without precedent, he waved it away with "That's was only tested on monkeys" to which I somewhat testily replied, "They don't test on humans." At least it did shut him up. But isn't it interesting when they are dismissing our claims the mice are trotted out to intimidate you yet my monkeys are dismissed to intimidate me. These poor animals can't win; their sacrifices for science are meaningless.

I love them trotting out your vegetarianism, which is, of course, a legitimate concern with B12, but you were getting two injections a WEEK, for the love of God. If it was just a nutritional problem then it would have sorted itself out in double-quick time on that kind of regime. As for smoking, they are always telling us the body starts to repair itself immediately as soon as you give up. I don't know when you stopped, but I fail to see why it would be a problem with B12 on 2 injections a week. Again, any issues would resolve quickly if you give your body lots of B12. After they brought drink in too did you begin to feel they were kind of giving you a 'You're a victim of your own lifestyle' vibe there? I'm surprised they didn't cross-examine you on your sex life.

I'm really lucky in that regard, I have no vices, not smoking, drinking or evil vegetarianism, so they can't pull the 'You done this to yourself' card on me. Poor things. But this will amuse you - perversely, again, when I was trying to get my injections I had actually had a really bad diet, unintentionally. I'd been very sick with gallstones for a year and a half (a long story) and I had eaten a very low/no fat diet with no red meat. On top of that I had an operation, then I had adopted vegetarianism and then veganism briefly - all of which must have wreaked absolute havoc with my B12. When I told my doctor this, he wasn't having any of it. So, in your case, it was the vegetarianism and the evil vices, in my case it wasn't the vegetarianism and the evil no-fat starving. And they wonder why we get confused and pi**ed off and don't trust them and their mixed messages?

It would be funny if it wasn't all so darkly tragic. Ah hell, it is funny. It's either that or cry.

Anyway, b*tching aside, I have moved my appointment to 4 days before my next injection. If I am not showing elevated MMA or Homocysteine (I doubt that will be elevated) by then then I'm guessing I don't actually have a problem. Or certainly it would indicate that enough B12 is being carried through from injection to injection so that's not really my issue.

Incidentally, when I asked what tests I was getting the receptionist said "Organic Acids & Homocysteine". That worried me, but Organic Acids appears to be a whole host of metabolic marker tests, so I don't know if they are doing more or this is just how The Biochemist refers to it. I hope to God it's the right test though! That wouldn't be funny. I keep telling myself,' Of course it's the right test. Stop being neurotic' but sadly I've experienced problems with tests before. I needed a special test for Celiac disease because I have partial IgA deficiency and THREE TIMES they gave me the wrong test, and they lost the results twice. So you can see why I am worried. Hopefully though my neurosis is misplaced and all will be well. I shall be thinking of you and trying to send cosmic mind vibes to your haematologist/s to help them get with the programme.

P.S. Genetic testing? That's fab. Hard to get, and it should give you some really good info. Result right there.


Still think vegetarians NOT at risk; absolutely sure that it would not take over 35 years to become marginally deficient if so. Where is the proof? Like I said, most of the existing "proof" (research reports) seems to come from people who do not recognise the difference between vegetarians or vegans - luckily, eggs and cheese are B12 sources.

About MMA and homocysteine tests: please see my latest post (today) about phone call from haematologist yesterday. Something to think about, not trying to worry you, okay?

What is partial IgA deficiency ? You've got yourself quite a collection, Chancery!

All the best,



I've seen (and replied to) your other post, Cheryl - what a disappointment for you. It seems to be wandering off with a life all of its own, doesn't it? If I were to be cynical I'd say it looks like they're trying hard to make it NOT Functional Deficiency. Has anyone given you an actual reason for why they seem so determined that it ISN'T Functional? Is it the brainless terror of you becoming a B12 crack-wh*re?

Partial IgA deficiency is when you have low IgA (surprise!). IgA is 
and a deficiency causes more infections of the gut, skin and respiratory tract. It is also strongly associated with autoimmune conditions, none of which I have. Because mine is only partial (i.e. it is lowish, not absent) it is not taken seriously, although there is a high correlation with coeliac disease. If you have it you are supposed to have different tests for coeliac because the deficiency causes false negatives. I had to fight like the very devil to get the more unusual IgG test and it's where I first encountered The Biochemist, who decided that my IgA "wasn't low enough" to merit the different test. I questioned how the hell he could possibly know that and after a LOT of fighting and many wrong tests I got my super-special IgG test - and it was negative. So problem solved; I didn't have coeliac disease. And, of course, yet more proof that I'm neurotic, with a penchant for fantasy illnesses.

Wouldn't it be hysterically funny though if I've had coeliac disease all along and that's why I have B12 issues and now numb legs and so forth? If so, I wonder if I could sue....


You may also like...