My question is about reference ranges for iFAB and MMA tests.
My MMA was 26.8 ug/l and the reference says >32 is an issue.
My iFAB was 1 AU/ml and the reference range is >1.2 is an issue.
I’m just wondering how these cut-off points are set e.g. did somebody in the lab just decide that results over those points will catch most people, and so there’s no real reason why one person with a result of 33 couldn’t be fine when a person with a result of 32 could be suffering?
I know that a b12 deficiency diagnosis is notoriously hard to pin down through tests, and that anti IFABs are only picked up around 50% of the time, but I had wrongly assumed they would either be present when my test was done or not. I wasn’t expecting a continuous range with a cut off point. I have been trying to find literature on the reference ranges for both these tests to see if there are grey areas and am struggling. It doesn’t help that Medichecks mma units are not in umol or pmol.
Can anyone point me in the direction of helpful reference material? I’m prepping for a visit to my GP.
For context, my active b12 was 65 when tested in jan, which was what prompted me to take these other tests. It went up to 99 when tested in feb along with the mma and iFAB tests. My vitamins are at the low end of ranges, as are my haemoglobin and haematocrit, I have a number of b12 deficiency symptoms, an unusual FBC result of neutrophils below range, other autoimmune diseases, laryngopharyngeal reflux, and a family history (both parents) of b12 deficiency.
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Sparklyjenson
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Well, this is exactly the problem - and it is one of perspective as much as anything.
I first went to the GP with fatigue, daily diarrhoea and lowerback/l/h hip pain.
Blood tests showed B12 deficiency (196 ng/L - with a normal range starting at 197 ng/L) - so I was started on B12 loading injections, then maintenance frequency.
This level would be too high to get treatment in some areas of the UK.
My GP, realising that the conventional 1-every-three-months regime for B12 deficiency was not helping me at all, had my MMA tested. It came back raised (351 nmol/L, with a range of 0-280 nmol/L). She had already ruled out renal problems by blood test, so the lab confirmed her diagnosis of functional B12 deficiency. I was restarted at a frequency of 2 injections a week. My GP told me that she had only ever had one other patient with raised MMA, ten years previously, and that this patient also had had functional B12 deficiency. That raised MMA was very rare.
Later, haematologists tested my MMA another 4 times
(364, 351, 393, 308 nmol/L).
My MMA levels were always referred to in medical reports as "raised" not "high".
I was sent to Adult Inherited Metabolic Diseases consultants at a major hospital who looked at my DNA to see if there was any explanation for malfunction - they could not find any reason. They were kind, apologised for not being able to help, disappointed for me. Unlike my GP, they were familiar with cases where MMA was many times higher than these results. This is because it can continue to build up in the bloodstream if there is insufficient B12 to link with it.
At the sixth and final check, my MMA was safely within the range at 205 nmol/L. It had taken three years of frequent B12 injections.
I was sent to have a fasting breath test series to rule out SIBO (small intestine bacterial overgrowth) -the results were inconclusive (SIBO /IBS) but GP trialled me with antibiotics for SIBO, since this was what was being ruled in/out- beyond having an adverse reaction to the antibiotics, nothing changed, so SIBO was dismissed.
I have had a couple of IFAb tests -both negative.
My folate and ferritin levels were low within range, although my hair was falling out and my gums bleeding - it took about 2 years to get these up to a more useful level and stabilise there. I am still on vitamin D tablets and Raloxifene because osteoporosis of the spine was found - at the last test it has been demoted to osteopenia. The advice was that the treatment was working, so to continue with it.
I also follow this logic with my b12 injections.
I believe that my GP was right about functional B12 deficiency, although the cause could not be found. I have had plenty of other tests over the years- and nothing else has been found in seven years. I continue to self-inject at the frequency that she used: 2 injections a week. This is not a miracle cure for me -but it has stopped me getting worse, and slowly I have seen very gradual improvements.
I was very lucky to have such a thorough GP.
Stichting B12 Tekort have very good research papers on B12 deficiency and MMA tests.
Very interesting Cherylclaire . You were indeed fortunate to have a good GP. That’s a real rarity where Pernicious Anaemia/ B12 deficiency is concerned. Why is that i wonder ! ? ……….. . I feel bad saying this , but i really envy you having such a GP. ( envy is such a horrible trait)
Well, if it makes you feel better:When she was on holiday and I needed a GP, I once went to a new one that I didn't know - and he didn't like my SI regime, so had my NHS injections stopped before her return ! And people moan about how slowly the NHS works........Better now ? Here to help, whatever the problem.
Envy is a human flaw. Your honesty shows you aren't a lost cause !
I remember feeling the same way when people talked about jogging/cycling/going to the gym - even though I never did any of these things when well.
Goes to show that it is worth doing what Nackapan did - try out all the GPs at the practice until you find the best one for you. They aren't all the same and they will approach a problem quite differently.
Hi cherylclaire, I really appreciate you taking the time to share your story. It’s interesting to hear the level of your mma and how long it took to come down. I had b12 at 195 a few years and that was not low enough at the time for the gp to treat it. If I had been with your gp perhaps things would be different! I also have osteopenia - I broke my foot walking across the road when I was only 40. I take vit D 4000iu per day and that keeps my levels at the low end of the range. My latest dexa showed no deterioration. Hooray!
I’m pleased that your treatment is having a positive impact.
I will take a look at stichting b12 temper. Thanks for the tip.
I do a lot of walking now which I think helped my osteoporosis of the spine improve.This was not always the case: my original notes say "regular exercise not possible"- as I was struggling with getting back from the shops then (not caused by osteoporosis but B12 deficiency!)
If you look at the right-hand column on this page, you will see a heading "Pinned Posts" and then if you click on the "see all" arrow, you will find a post with all the links to Stichting b12 Tekort re B12 deficiency. Take your time -there's a lot of info to take in.
Brilliant - I’ll enjoy working my way through the info in the stichting post. It’ll save me such a lot of random googling time! Much appreciated and I think it’s amazing that you actually reversed the osteoporosis.
No, they told me after my diagnosis that I should try to stop it deteriorating but I didn’t know you could actually strengthen your bones once you had passed your 20s.
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