QUESTION: There have been many threads about high B12 in bloodwork as a flag for myeloproliferative disorders. Is there an issue doing a trial of B12 in a patient with suspected myeloproliferative disease? Doctors have made the recommendation that a bone marrow biopsy wouldn’t be in the patient’s best interest at this point as they are planning to monitor and do blood transfusions as needed. Consistently low Hb, Hct, low RBC, low normal B12, very high folate, macrocytosis. Patient is on a completely liquid diet, all folate and B12 are synthetic, not bioavailable forms (ensure and Peptaman by feeding tube). Patient is also on proton pump inhibitors and is 79 years old and experiencing terrible fatigue and breathlessness on exertion likely from the chronic anemia. I would like to do a trial of B12 shots (methylcobalamin) and 5-mthf but I just want to double check whether the myeloproliferation was a contraindication for B12 or just could be a factor in an elevated blood result of B12.
ANSWER: Here is the short version: Elevated B12 in cancer and some liver (and other inflammatory states) is an EFFECT of the disease, never a CAUSE. In fact sometimes B12 is used in cancer treatment as an antineoplastic. So, while the elevation of B12 is seen occasionally in some cancers etc, there is no connection between that and any issue giving B12. two separate processes. And in fact normally what “looks” like high B12 is useless forms of B12 dumped by the liver in the neoplastic/hepatic or other inflammatory process. [in this case the low B12 is truly an issue…] So in fact even though their B12 is “high” (rarely a measure of nutrient status in these cases BTW) the high level is useless cobal’s. All that said, (and I have a whole rationale for this we had to use in the NIH cancer research I’ll probably publish some day) in any active cancer or other cause of this false elevation of B12 repletion is necessary. So in MPD or other things yes please do replete, and once at a more normal H&H etc then go to a maint dose of the nutrients. If the Ferritin is actually low treat that part till it is 40-50. If ferritin is high (as it appears above) it is likely inflammatory (like the high B12) and not a marker of nutriture.