Guidelines from the British Columbia Guidelines and Protocols Advisory Committee (2012) recommend performing a CBC, blood film and serum cobalamin in all patients suspected of cobalamin deficiency. The guidelines recommend interpreting serum cobalamin levels in light of clinical symptoms, because the test has the following limitations: 1) it measures total, not metabolically active cobalamin; 2) the levels of cobalamin do not correlate well with clinical symptoms; elderly patients may have normal cobalamin levels with clinically significant cobalamin deficiency, while women taking oral contraceptives may have decreased blood cobalamin levels due to a decrease in transcobalamin, a carrier protein, but no clinical symptoms of deficiency; 3) there is a large ‘gray zone’ between the normal and abnormal levels; 4) the reference intervals may vary between laboratories. The guidelines state that the conventional cut-off for serum cobalamin deficiency varies from 150-220 pmol/L. Using a more common cut-off of 220 pmol/L, the guidelines recommend the following interpretation:
Hello Janyce, great finds! (as always...)
Sometimes oldies ARE goodies!
Good "ammunition" to bring to our doctors.
I found two interesting points in these studies: (i) alternate-day prednisone and (ii) used of isoniazide.
(i) I wish more work (more studies, more patients, more recently) was done (and continued to be done) comparing daily to alternate-day therapy with detailed follow up of both efficacy (as these studies have done) and side effects - side effects both during and after tapering off (which they didn't follow or followed but not in a lot of detail).
IMO this is worth a large, detailed multi-center trial, but getting funding for such study would not be easy in the age of more "fancy" approaches such as monoclonal targted antibodies (humira, remicade) and stem cells.
(ii) It's interesting that in two of the studies that present individual cases, some of the patients were given, in addition to prednisone, also isoniazide.
Quoting from the last article "Isoniazide in a dose of 300 mg daily, was administered only until mycobacterial cultures were found to be negative six weeks later."
Isoniazide (Nydrazid) is an antibacterial (. used in tuberculosis), which is a very interesting aspect of these studies, but somehow is mentioned as an after-thought, unimportant factor in these treatment.
The focus is on prednisone, but why not highlight also on isoniazide? I find it curious.
Perhaps the idea that sarcoidosis may be caused (in some patients?) by a bacteria or mycobacteria wasn't in the forefront.
I also find it intersting that the patient in case study 1 in the 3rd article was checked for mycobacteria and isoniazide was given until tests showed no more mycobacteria.
Were you (Janyce or anyone else) checked for mycobacteria?
I was checked for TB (which was found negative on an antibody-based blood test) but not for other mycobacteria.
Yes, I know that mycobacteria was discussed on a number of posts, and we still don't know much about it... etc. etc. (I was involved in some of these discussions), but the fact that they used isoniazide in the 1970s and 1980s, whereas now my doctors (these are doctors who were trained at top medical schools at work at a very high-end medical clinic) don't even mention it and don't test me for mycobacteria (or other bacteria) except for TB is a worthwhile point.
Thanks again and all the best.