Originally Posted by mrsD

B12 can get elevated from what is called a dysbiosis in the bowel.

When certain organisms start to proliferate, sometimes after antibiotic treatments (usually oral), those organisms can make B12 and you absorb it that way.
http://www.cnelm.co.uk/Nutprac/vol9i...LevsB12.GM.pdf

There are other disease states that raise cobalamin when no supplements are taken:
http://www.ncbi.nlm.nih.gov/pubmed/14636871

http://www.ncbi.nlm.nih.gov/pubmed/17981373

I do hope for your sake that the resurgence of your symptoms are not related to a malignancy.... this type of PN is called paraneoplastic.