In my random readings about B12 this morning I came across another reference to the Schilling Test. This is an excellent method of testing for B12 deficiency and determining the cause. However, it requires radioactive cobalt - and nobody makes it any more, so nobody can do the Schilling test. - en.wikipedia.org/wiki/Schil...
I propose to start a petition asking the government to fund a university department to manufacture the required radiolabelled cobalt. However, I need 5 people to support it. If you think this is a good idea, please follow the link below.
Edit: The petition is now live, thanks for the support so far. Please publish the following link to social media etc., to spread the word. petition.parliament.uk/peti...
Fund university expenditure for the production of radiolabelled Vitamin B12
People with Vitamin B12 deficiency caused by Pernicious Anaemia have problems with diagnosis because the available tests are inaccurate. The Schilling Test can accurately diagnose the cause of Vitamin B12 but is no longer performed because nobody makes the radiolabeled cobalt required.
Vitamin B12 blood tests are inaccurate. The test for the antibodies responsible for PA is only accurate 50% of the time. The Schilling Test requires radiolabelled cobalt. A government-sponsored source could make it possible to reinstate this test.
There are now enough supporters for it to progress to the next step, where they check to ensure it meets their rules. It should be about a week, then we can share it.
I was perhaps "fortunate" to have been diagnosed with P.A. having had "Schillings Tests" done in 1968 and 1972. Why the first was "inconclusive" I shall never know - maybe I didn't follow the instructions properly as it involves the collection of "gallons" of radioactive urine over (I think) a two day period. Hard to remember now.
My guess is that there were one of two possibilities - either it was too expensive, or there was an alternative use for it and that use stopped.
The good thing about radioactivity is that it's very easy to detect small amounts of it. So you only need tiny doses. In the last year I've had radioactive Indium and radioactive Gallium squirted into my veins.
I would bet that the discussion was about carbon-14 labelled B12. There are a couple of studies done recently that used 14-C cyanocobalamin. They had to use a technique called accelerator mass spectrometry because the amounts are so small. AMS machines are, very, very expensive (we had one and I think it was something like 3 million quid) so not much good for large-scale medical studies.
The Schilling test used radio cobalt - using an isotope that released gamma rays. That makes it much easier to monitor small amounts, because the radiation is more energetic. However, it's difficult to make (I'm not sure how they do it but a bet a particle accelerator is involved).
14-C labelled cobalamin would be fairly easy - just grow some bugs that make B12 is a medium with 14-C labelled sugars should do it.
From what I read, the problem with the Schilling test, at least in the UK, was its use of bovine substance(s). During the height of the BSE crisis, this was seen to be a reason to withdraw it and it has never since been returned to the market.
There could be any number of other issues with Schilling test reagents.
Some time ago, I saw a rumour that non-bovine reagents were in development.
I took this Schilling test in year 2000, I took the first part which showed abnormal results and was given a diagnosis of PA, but I never took the second part as the test machine broke down and was never replaced, so I do not know the cause. My mother had PA, and I tested negative for IF antibodies.
The Disappearance of Cobalamin Absorption Testing: A Critical Diagnostic Loss1
Ralph Carmel*
Department of Medicine, New York Methodist Hospital, Brooklyn, NY 11215, and Weill Medical College of Cornell University, New York, NY 10021
When the manufacturer of the most popular Schilling test kit (Dicopac, Amersham Health) discontinued its licensing in 2003, mainly because of concerns of potential transmission of bovine spongiform encephalopathy via its animal-derived IF dose, much of the medical community's reaction was muted. In fact, requests for the test, whose costs exceeded reimbursement by health insurers, were already in decline. I know of no American manufacturers who provide radioactive cobalamin test doses or IF today.
Technical restoration of tests of free cobalamin absorption (e.g. the Schilling test) is the most urgent of the tasks. It could also be the least difficult to achieve. The pressing need for a safe source of IF seems likely to be met with the newly reported recombinant IF (24), which needs careful but expeditious confirmation. Manufacturers will probably be able to restore production of 57Co-labeled cobalamin once the IF source is available, but commercial viability may lag until demand revives. Introduction of 14C-labeled cobalamin (25) may ultimately add the advantage of less exposure to radioactivity once its technical issues are resolved. Suggested alternatives to the Schilling test, such as serum sampling for holo-transcobalamin II after oral cobalamin, await more documentation.
Later in same article
As I know so little, maybe this 2007 paper has been overtaken by events? Perhaps some of the hoped-for steps have proved to not be viable?
I didn't know about the mad cow worries about IF, but it looks like that may be fixed. Which would mean that it's the financial blocks are all that's stopping the production of 57-Co. And that's just the sort of thing that I believe governments should be spending their money on.
As I mentioned above, C-14 B12 is much easier to make, but much harder to detect in small amounts.
Elsewhere there are numerous mentions that the cost of a single Schilling test could easily be greater than life-long monthly injections for an individual.
By the way, I had no idea about any of it - just that there are numerous references to the test but no-one ever gets it done. Makes you realise how poorly maintained many websites are. It wouldn't take much effort to add "Not currently available". However it would take awareness and motivation.
I've only just come across this, so I apologise for the delay. The Schilling test was a superb diagnostic tool, but a little long-winded. It was further developed into the 'Dicopac' test which simplified the procedure from the patient's point of view. It used two Cobalt isotopes. The process required the patient to swallow two capsules; one of these contained bound (B12 + IF) and the other unbound (B12). This allowed the laboratory to demonstrate the presence, or absence, of IF. The IF used in the test was, as I recall, porcine. So, the test required two different Cobalt isotopes and a supply of pig intrinsic factor. It was easy to perform but not suited to large numbers.
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PA tests negative... how accurate are they?
wow! My new doctor has PA himself!!
Long standing PA -can I ask for blood tests?
CT scan instead of gastroscopy / colonoscopy with all PA tests normal
