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Is Vitamin B12 Level Of 203 Pg/ml A Cause For Concern?
Question: For some time now I have been experiencing many different symptoms such as burning in feet when standing or walking, vibrations in feet, muscle twitching, burning in eyes (no eye sight disturbances) and generally muscle aches/pains (back pain, shoulder pain). I went to see a neurologist and after doing a detailed neurological exam he wrote blood test for ESR, anti dsDNA, CRP, ANA (basically a panel to check for autoimmune diseases) after all the results came back negative he said neurologically you are perfect and you do not need further neurological examination. (I had asked him about if he suspects MS based on my symptoms but he said No, based on how I did in my neurological exam.
Two weeks later I went to a different neurologist and he did neurological exam (not as detailed as with the 1st neurologist) and said that he would like to check for B12, lyme, TSH, and heavy metal screen. Along with brain MRI without XXXXXXX as a precaution. MRI came back negative, and lyme, TSH, and heavy metal came back negative as well. Only thing that came up was low vitamin B12 (serum levels) of 203pg/mL. I asked him if he thinks my symptoms are because of low vitamin B12 and not anything else and he said he is positive its because of B12 and will administer B12 injections along with oral supplements. I asked him if he thinks spinal cord MRI should be done to rule out anything else like MS and he said there is no need for spinal MRI as Brain MRI is negative and vitamin B12 is low hence your symptoms are due to low vitamin B12.
He has given me one B12 injection and asked me to take 5000mcg of sublingual methylcobalamin daily. I have been taking this pills for about 1 week now but haven't noticed any improvements.
My question is that are my B12 levels of 203pg/ml low enough to cause this symptoms. (My vitamin D level is also very low). I would like some feedback (2nd opinion) regarding his diagnosis and how long do I need to take b12 to see any improvements.
Two weeks later I went to a different neurologist and he did neurological exam (not as detailed as with the 1st neurologist) and said that he would like to check for B12, lyme, TSH, and heavy metal screen. Along with brain MRI without XXXXXXX as a precaution. MRI came back negative, and lyme, TSH, and heavy metal came back negative as well. Only thing that came up was low vitamin B12 (serum levels) of 203pg/mL. I asked him if he thinks my symptoms are because of low vitamin B12 and not anything else and he said he is positive its because of B12 and will administer B12 injections along with oral supplements. I asked him if he thinks spinal cord MRI should be done to rule out anything else like MS and he said there is no need for spinal MRI as Brain MRI is negative and vitamin B12 is low hence your symptoms are due to low vitamin B12.
He has given me one B12 injection and asked me to take 5000mcg of sublingual methylcobalamin daily. I have been taking this pills for about 1 week now but haven't noticed any improvements.
My question is that are my B12 levels of 203pg/ml low enough to cause this symptoms. (My vitamin D level is also very low). I would like some feedback (2nd opinion) regarding his diagnosis and how long do I need to take b12 to see any improvements.
Brief Answer:
Read below.
Detailed Answer:
I read your question carefully and I understand your concern.
Vitamin B12 deficiency can certainly cause many neurological symptoms including the ones you describe, so it is a valid hypothesis. Whether those values are enough to say that there is a deficiency though depends also on the method used. That is because there are two types of assays to measure vitamin B12 levels, radioassay and chemiluminescence. For the first reference range is 170-900, while for the second it's 250-1100. There can also be small variations between laboratories in their reference range.
So if the first method would put it in the normal range, though low normal, if the second method was used it would be slightly low. I would say that whichever method was use that result is not considered definitive and more tests are needed to confirm the diagnosis. When vitamin B12 levels are borderline then two other lab tests are usually done, the methylmalonic acid (MMA) and homocysteine levels (HC). If those turn out level then there is no vitamin B12 deficiency, while if they are elevated they would support the deficiency diagnosis.
I would also do some other tests of nerve damage like nerve conduction studies and evoked potentials. The MRI of the spine may also be done in Vitamin B12 deficiency as it may cause lesions of the spinal cord.
MRI is not needed for MS though, I do not think that is an issue, your symptoms do not suggest that and the normal brain MRI supports that as well.
As for time needed to feel improvement, even if the diagnosis is correct you have to wait some more. Levels of MMA and HC need a couple of weeks to normalize and improvement of the symptoms may continue for as long as 6-12 months, so it is too early to come to any conclusion on response to therapy.
I hope to have been of help.
Read below.
Detailed Answer:
I read your question carefully and I understand your concern.
Vitamin B12 deficiency can certainly cause many neurological symptoms including the ones you describe, so it is a valid hypothesis. Whether those values are enough to say that there is a deficiency though depends also on the method used. That is because there are two types of assays to measure vitamin B12 levels, radioassay and chemiluminescence. For the first reference range is 170-900, while for the second it's 250-1100. There can also be small variations between laboratories in their reference range.
So if the first method would put it in the normal range, though low normal, if the second method was used it would be slightly low. I would say that whichever method was use that result is not considered definitive and more tests are needed to confirm the diagnosis. When vitamin B12 levels are borderline then two other lab tests are usually done, the methylmalonic acid (MMA) and homocysteine levels (HC). If those turn out level then there is no vitamin B12 deficiency, while if they are elevated they would support the deficiency diagnosis.
I would also do some other tests of nerve damage like nerve conduction studies and evoked potentials. The MRI of the spine may also be done in Vitamin B12 deficiency as it may cause lesions of the spinal cord.
MRI is not needed for MS though, I do not think that is an issue, your symptoms do not suggest that and the normal brain MRI supports that as well.
As for time needed to feel improvement, even if the diagnosis is correct you have to wait some more. Levels of MMA and HC need a couple of weeks to normalize and improvement of the symptoms may continue for as long as 6-12 months, so it is too early to come to any conclusion on response to therapy.
I hope to have been of help.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Hello Dr. Taka,
Thank you for your reply. I forgot to mention that neurologist also did nerve conduction test on my legs and he said the results were normal. I also believe that my serum B12 levels were measured through chemiluminescence assay and lab's reference range is from 211pg/ml to 950pg/ml. The doctor knew that I am a vegetarian and that may have led him to believe that I am deficient in b12 and didn't order MMA test to confirm.
But my follow up question is that right now is it too late to do MMA blood test since I have already started taking 5000mcg of b12 daily for about a week and have already received one b12 injection?
Does the clear brain MRI along with normal neurological exam and "low" vitamin B12 rule out MS? I am getting lots of weird symptoms/sensations such as vibrations in feet, fingers, feeling as if there is water drops on my skin (lasts only a second or two), tingling in my head (also just lasts couple of seconds) could these symptoms be related to B12 deficiency?
Thank you for your reply. I forgot to mention that neurologist also did nerve conduction test on my legs and he said the results were normal. I also believe that my serum B12 levels were measured through chemiluminescence assay and lab's reference range is from 211pg/ml to 950pg/ml. The doctor knew that I am a vegetarian and that may have led him to believe that I am deficient in b12 and didn't order MMA test to confirm.
But my follow up question is that right now is it too late to do MMA blood test since I have already started taking 5000mcg of b12 daily for about a week and have already received one b12 injection?
Does the clear brain MRI along with normal neurological exam and "low" vitamin B12 rule out MS? I am getting lots of weird symptoms/sensations such as vibrations in feet, fingers, feeling as if there is water drops on my skin (lasts only a second or two), tingling in my head (also just lasts couple of seconds) could these symptoms be related to B12 deficiency?
Brief Answer:
Read below
Detailed Answer:
Thank you for the additional information.
Your value with that reference range is borderline, I wouldn't call it clear cut and I would certainly have liked to order MMA test. Whether it has any value now, it might since MMA values need up to 2-3 weeks to return to normal, however it does not offer the same certainty it would if done beforehand. I would say if it results altered now it would confirm the diagnosis and it would certainly be credible, but if it results normal it does not exclude it.
As for MS, yes, I am pretty confident in excluding that diagnosis. As I said the symptoms if alone do not suggest MS and that coupled with the normal exam and MRI is enough in my opinion to exclude it.
Whether vitamin B12 deficiency can produce such symptoms, yes it can and given the fact you are a vegetarian it is even more possible. However the value is borderline. Adding to that the normal nerve conduction studies I wouldn't feel that certain as those symptoms are not very specific, meaning they can be found in many other cases, even anxiety might well be a possible common cause. That is why I would have felt more confident about the diagnosis if the MMA supported it.
Read below
Detailed Answer:
Thank you for the additional information.
Your value with that reference range is borderline, I wouldn't call it clear cut and I would certainly have liked to order MMA test. Whether it has any value now, it might since MMA values need up to 2-3 weeks to return to normal, however it does not offer the same certainty it would if done beforehand. I would say if it results altered now it would confirm the diagnosis and it would certainly be credible, but if it results normal it does not exclude it.
As for MS, yes, I am pretty confident in excluding that diagnosis. As I said the symptoms if alone do not suggest MS and that coupled with the normal exam and MRI is enough in my opinion to exclude it.
Whether vitamin B12 deficiency can produce such symptoms, yes it can and given the fact you are a vegetarian it is even more possible. However the value is borderline. Adding to that the normal nerve conduction studies I wouldn't feel that certain as those symptoms are not very specific, meaning they can be found in many other cases, even anxiety might well be a possible common cause. That is why I would have felt more confident about the diagnosis if the MMA supported it.
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Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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