I had blood work done at the onset of my POTS/DYSAUTONOMIA symptoms. The only abnormal results were Neutropenia, LO ferritin and VERY HI B12 (I was not on B12 supplements). The ferritin was corrected but the B12 continued to be HI until about 8 months ago. I don’t know why it was HI in the first place but it does seem unusual to have too much B12 instead of not enough. Also, I now have chronic mild Neutropenia.