Even though this post is not about b12 and PN, it's relevant in that this study confirms normal blood serum levels cannot be relied upon to diagnose anemia and cannot be ruled out in cases of anemia and PN. Like Mrs D states in earlier posts, most doctors believe you need to have a below normal B12 result for it to be considered as a possible cause for the blood or bone marrow disorders as well as PN. And if you're not anemic, your PN cannot possibly be from low B12 status. Well this study pretty much debunks this medical myth.

My husband had Severe Aplastic Anemia back in 2002. I wish I knew this back then so we could have tried B12 as his first line of treatment. Especially during that waiting period of getting a final diagnosis. We had two months before he started treatment. His B12 was normal at the time...I think it was under 500 though.

http://www.ncbi.nlm.nih.gov/pubmed/21252496

In the 12 cases here, all three lines, red cells, white cells and platelets were low.