I folks I have elevated B12 levels and neuropathy symptom...burning tingling in my legs. I was diagnosed with SIBO small intestinal bacterial overgrowth. I am in treatment for SIBO but my b12 blood tests keep getting higher and the pain is getting worse.
Suggestions please if I should get further testing to ensure my body is utilizing b12.
Thank you.
Hi
I’m not as knowledgeable as others on here but can speak from experience. My mother in laws b12 was high 923 without any supplements and poor diet. I had further testing done of MMA and homocysteine levels with a haemotologist. My mother in law had no b12 at cell level and was diagnosed with pernicious anaemia even though Antibodies were negative (takes a lot of attempts to get a positive apparently).
So I would suggest further testing of homocysteine and MMA and perinatal cells (not sure of the spelling on the last one)
Hope that was helpful rather than confusing!
Good luck
dancingdp - have you had any B12 treatment - it isn't quite clear from your post.
If your B12 levels are above range without supplementation then it would be a good idea to get some tests done for liver and kidney function.
Functional B12 deficiency is a possibility if you have elevated B12 levels and the symptoms of B12 deficiency in the presence of high serum B12 is recognised as an early warning of some conditions affecting liver and kidney function.
As per specialk16 - MMA and homocysteine are tests that look at harmful products that build up if your cells don't have enough B12 to recycle them but they can also be raised by other things - so need to be done in a context that rules out other reasons.
PCA and IFA are tests for PA as a specific cause of a B12 deficiency rather than tests for B12 deficiency (think the 'perinatal' should be parietal cells) so not really worth doing at the moment.
After I started having B12 injections, once loading doses were completed and put on 1 injection every 3 months, I got a lot worse: my high B12 levels (>2000 nmol/L) and raised MMA was diagnosed as Functional B12 deficiency, by GP and confirmed by the hospital lab if renal problems ruled out (all tests done simultaneously- GP's a good one) .
Because I did not also have raised homocysteine levels and because MMA did not alter just before/ just after B12 injection, haematologists decided that raised MMA wasn't a sign of Functional B12 deficiency but could be due to SIBO. Had the Lactulose breath test which showed either SIBO or IBS ("fast transit to colon").
Probably SIBO then (?) - difficult to say as I don't have enough information to question haematologist's undiagnosis or the tests done/ timing of tests in relation to injections, or any understanding of IBS's effect on vitamins/ MMA levels or how IBS is diagnosed other than by elimination- and as with depression/ anxiety: a strong bias toward female patients.
I agree with Gambit62 -would have thought liver and kidney function blood tests should be done, as well as MMA and homocysteine. Still very difficult to find much information about Functional B12 deficiency; rock-solid diagnosis or treatment.
Raised MMA alone can be an indicator of SIBO, raised homocysteine alone can be folate deficiency. Treatment for SIBO with antibiotics can affect B12. I had Doxycycline, which gave me vertigo, balance problems, nausea and face pain (headache/ gums/ toothache/ cheekbones/ sinus, I couldn't say)- which could have been a B12 blip or just a bad reaction.
As regards MMA levels, Stichting B12 Tekort say mildly raised MMA in adults is almost always B12 deficiency, the Inherited Metabolic Diseases consultant I have seen disagrees and says that his patients with B12 deficiency have very high MMA results.
Dancingdp - why was SIBO suspected ? Have you had MMA or homocysteine tests ? Why was your B12 tested initially ? Were you/ are you having B12 injections ? Do you have any other symptoms ? Yes, yes, yes have more tests.
Cherylclaire it took many years to discover SIBO was the cause of severe distention and cramping. The breath test confirmed high methane production in the small intestine.
I have been in an herbal protocol taking Antrantil, Berberine, Zinc Carmosime, low dose neltexone, armor thyroid for hypo, N-Acel-l-l-Cysteine.
My symptoms of SIBO are much better and my numbers are much less which is great but the neuropathy is a mistery. What is MMA?
MMA is Methylmalonic acid and can be serum- tested on NHS (if you are in UK). It has been promoted as a reliable secondary test for B12 deficiency (after serum B12- which can only say how much B12 active or inactive is in your blood system, not what reaches cellular level) but is quite expensive I believe, and not widely available: local hospitals would be unlikely to be able to facilitate. Quite often, it is a consultant who would ask for this test. It can also be urine-tested I think, but this would be more unusual.
MMA links up with B12 as part of the process, and so if you have an excess of MMA floating about in your bloodstream, it could be due to insufficient B12 available to make the link. I'm not sure what that would say about SIBO, unless it is for the same reason: in that case, B12 unavailability due to bacteria hogging it all !
Bit lost right now about whether I have or have not got SIBO/ Coeliac disease/ IBS/ B12 deficiency/ Functional B12 deficiency/insufficiency. Or a combination of these. Also have to keep supplementing folic acid and ferritin otherwise levels drop (no matter how healthily I eat), and hair falls out, gums bleed and mouth cracks at corners. Still have cognitive problems and can lose energy quickly.
Can't understand why, with having been diagnosed with SIBO, your B12 level wasn't low instead of high. Since the bacteria thrive on your vitamins, your levels should have been checked then, any insufficiencies addressed with supplements (or at least advice), monitored, and any abnormalities or contraindications should have been investigated. Was hydrogen level breath-tested as well as methane ?
Thank for you reply Cherylclaire
Yes to you question both hydrogen and methane were tested several times via Lactulose Breath Test. I'm going to ask my naturopath about further investigation of the elevated b12.
Thank you dearly.
Thanks for your response Gambit62, I am not supplementing with b vitamins to be clear. My b12 is currently reading 1398. Optimal looks like it is up to 946. My b12 has been climbing and I'm loosing my hair.
I'm also on Armour for Thyroid. My blood work looks ok except all other b's are on the lower end.
not sure what you mean by 'optimal' as that would vary from individual to individual. If you mean that the upper point on the 'normal range'for the test was 946 then you shuld be asking for tests for liver and kidney function. Problems with both can result in elevated B12 levels
I found that taking a 50mg Allithiamine capsule every morning helps diminish my neuropathy/paresthesia. I also self-inject 1mg hydroxocobalamin twice a week.
I would love to know if you have an update on this. My son is in the exact same senario. SIBO, treated with xifaxan, but neuropathy symptoms worse and B12 is higher?
I hope everything is completely better! I would love to know how your son is doing? I have high B12 after being treated with Xyfaxin several times. Not sure what to do!
I am in the exact same situation as you. Do you have any updates? Hoping you're doing better.
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