How soon after starting B12 supplements should the serum B12 level be monitored? Is it necessary to stop B12 and if so for how long before checking levels in blood? Is monitoring actually necessary or is this a lifelong replacement programme based on assuming the deficiency to be the result of a failure of absorption, which has not been proven.
My son's GP seems to think that in a couple of months his B12 stores will be repleted and if the levels are satisfactory he can then stop the medication. This seems seriously flawed to me.
How soon after starting B12 can folate replacement treatment be started safely to avoid risking neurological deterioration.
The GP has suggested two weeks, but this appears to me to be totally arbitrary and presupposes that the oral replacement will have corrected serum levels and replaced adequate stores, which seems highly unlikely. Since he already has neurological symptoms this is of considerable importance.
I bow to the superior knowledge and understanding of so many health unlocked experts on these issues and thank you in advance.
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Dewbuc
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Think there is something in BSH Cobalamin and Folate Guidelines about further testing of B12 levels being irrelevant once b12 supplementation has started.
"GP seems to think that in a couple of months his B12 stores will be repleted and if the levels are satisfactory he can then stop the medication."
If it's PA, your son will need lifelong treatment.
If it's PA or another cause requiring lifelong treatment, stopping B12 when levels hit normal range could risk further deterioration even possibly spinal cord damage.
PAS have a leaflet for PAS members called "Treatment is for Life"
My understanding of UK B12 guidelines is that with people with B12 deficiency with neuro symptoms should receive B12 injections according to BNF Chapter 9 Section 1.2
I'd suggest it could be worth joining PAS and asking if oral tablets are an approved treatment for PA and other absorption problems. My understanding (I'm not a medic so I could be wrong) is that oral tablets are only recommended for dietary B12 deficiency.
There are stories I think are relevant to your situation on Martyn Hooper's blog including some that mention oral treatment.
"assuming the deficiency to be the result of a failure of absorption, which has not been proven."
Has he had an Intrinsic Factor Antibody test yet?
MMA, Homocysteine , Active b12 would be possible tests but because he has supplemented recently with b12, the results of these tests could be affected.
Thanks. He is scheduled for intrinsic factor in two weeks, a positive result would presumably be diagnostic, but I'm not sure how relevant a negative result would be. In view of its non toxicity it would seem to be safer to assume he lacks intrinsic factor and will need lifelong B12. Am I correct?
"I'm not sure how relevant a negative result would be"
This flowchart below from BSH Cobalamin and Folate Guidelines outlines when a negative result in IFA test can lead to a diagnosis of Antibody Negative Pernicious Anaemia
My experience in UK has been that there are plenty of GPs who are not aware that it is possible to have Antibody Negative PA.
I take a copy of this flowchart to appts where B12 is likely to be discussed.
Flowchart above makes it clear that if a patient shows a clinical response to B12 treatment eg symptoms improve then B12 treatment should continue.
Also makes it clear that treatment should be according to BNF, which as I have said on one of your threads, recommends B12 loading injections (not oral treatment) every other day for as long as symptoms continue to get better for those with neuro symptoms.
as Sleepybunny says the BCSH standards and NICE standards state that there is no need for monitoring of serum B12 levels unless there is a suspicion that the patient is not complying with treatment.
The GPs reasoning is flawed because it hasn't taken in to account how the body releases its stores of B12 so they can be absorbed back into the blood - ie B12 released in bile through to the ileum where it is reabsorbed - very efficient if you don't have an absorption problem but extremely inefficient/useless if you have an absorption problem.
On folate before B12 - the big concern is a very small number of reported cases of folate treatment in the presence of B12 deficiency precipitating SADC - however, its only a question of making sure that B12 serum levels are raised before using large doses of folate 24 hours should be sufficient - 48 if you really want to play it safe ... and it is a very rare complication. However there is no point in delaying much longer than this because folate and B12 are needed together for many of the processes the body uses B12 for so not having B9 will mean that these processes still won't function properly.
The precipitation of SADC has been subject to experimentation in fruit bats but, of course, there haven't been any human studies.
Think this is also covered in the BCSH guidelines ....
Folate deficiency shouldn't be treated in preference to B12 deficiency (or possible B12 deficiency because doing so can mask the development of macrocytosis - though personally I think this is a bit of a red-herring and the medical profession should formally recognise that macrocytosis is a symptom of B12 deficiency and not a defining characteristic - so they should stop giving it so much prominence in the diagnosis of B12 deficiency.
The latest BMJ research document (link below) states at bottom of page 4 ' under, 'How is Response to treatment assessed' ) that, once parental b12 is begun, B12 serum test results are not usually relevant as blood levels are not reflective of how effective the treatment is - it is the clinical condition of the patient that matters.
The document also contains information regarding frequency of injections for neurological symptoms, 'every other day until no further improvement' (British National Formulary) :
"Cobalamin and holotranscobalamin levels are not helpful because they increase with vitamin B12 influx regardless of the effectiveness of treatment, and retesting is not usually required."
This is a link to the summary but you'll probably be able to access the full document:
UK charity that offers free second opinions on medical diagnoses and treatment. They are usually quick to respond to enquiries. Think a full medical history is required.
There's a lot of B12 info in the pinned posts on this forum which might be of interest.
Also a section on PAS website for health professionals which might be of interest to son's GP.
I think sometimes the route to diagnosis/adequate treatment of B12 deficiency including PA is through other health professionals besides GPs eg
1) Neurologists for neuro symptoms of b12 deficiency
Has he seen a neurologist? Had a romberg test?
What I found was that of the various neurologists I saw, none of them gave me neuro exam/tests with my eyes closed which could have highlighted the proprioception problems I was beginning to develop. I used to wobble/stumble if someone walked directly towards me and I lost sight of my surroundings, also had balance issues at night.
2) Haematologists for blood symptoms including macrocytosis. BNF recommends referral to haemo if neuro symptoms present.
3) Gastro-enterologists for gastro symptoms eg gastritis
4) Dentists may spot sore swollen tongue (glossitis), mouth and tongue ulcers etc
5) Podiatrists .... for neuropathic symptoms in feet. In UK, podiatrists with right training are allowed to prescribe B12 injections for neuropathy in UK
He saw his GP first with foot drop and, at my insistence, he was referred privately to a neurologist. He was told that the nerve atrophy was due to sitting cross legged at work and that recent weight loss meant the nerve was not protected by fat! If that was the only aetiology then half the nation would have foot drop! Neither suggested a B12 deficiency, but both told him he was folate deficient. It was once again only at my insistence that his B12 was measured and found to be low. Neither asked about his family history.
The average patient in that situation would accept the diagnosis at face value and start taking Folate with the potential risk of exacerbating the symptoms. I despair of my profession!
Never stop B12 , Never, if your son eats a healthy diet with meat or animal products and still had pernicious anemia, then that means he has no intrinsic factor and cannot absorb B12 by food sources or going through the digestive tract. He must take sublingual or shots the rest of his life.
Thanks I am sure that is good advice. Again it is not the advice given by the GP! It is extraordinary and obviously quite a common approach of the medical profession.
And if I had listened to the first GPs I went to, I would be dead. NO exaggeration! They gave me zoloft, muscle relaxers, wanted me to have counseling etc. I have talked to many drs about it since and they mostly have no understanding of subacute combined degeneration for the most part. Most say they remember studying about pernicious anemia but have never seen bad cases. Again, if someone is not going through something that would cause a temporary B12 deficiency and they are eating animal products, they need B12 administered other than through diet for the rest of their life. It is a cheap cure for a potentially deadly disease and at minimum one that can cause lots of problems.
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