I received this as a blood result 3 weeks after receiving my b12 injection but I am confused. Does this tell me the level of b12 in my blood or folate? There are no other test results that refer to b12.
I am currently suffering very badly with the symptoms of low b12 despite having my 3 monthly injections 3 weeks ago.
It doesn't tell you either Folate or B12 - the sample(s) which were to be analysed had haemolysed (spoiled) so there are no results.
However, you do have a serum ferritin result. At 29.7, that is below the current bottom of acceptable which is at least 30 according to NICE.
Interpreting ferritin levels
Serum ferritin level is the biochemical test that most reliably correlates with relative total body iron stores. Low levels indicate low iron stores, except in women who are in the second or third trimester of pregnancy.
In all people, a serum ferritin level of less than 30 micrograms/L confirms a diagnosis of iron deficiency.
Ferritin levels can be difficult to interpret if infection or inflammation is present, as levels can be high even in the presence of iron deficiency.
Scientist, not medic.
Haemolysis is the process whereby red cells are destroyed. Red cells have a much higher concentration of folate than the serum, so measuring folate on a haemolysed sample would tell you nothing. Haemolysis is caused by either poor technique in collection, poor temperature control in storage, or prolonged delay before analysis. To be honest I'm surprised they measured anything on a haemolysed sample!
Start again... [I hope they get it right next time.]
haemolysed means that the sample is unusable - lab problem, not yours - and blood needs to be taken again.
There is little point in your serum B12 level being tested after the B12 injections have started.
If you have been found to have B12 deficiency already, then the treatment given is B12. Usually in the UK starting with a loading dose of 6 injections, all within a short space of time. This is intended to bring your level up very high very quickly. Then the maintenance dose, which is usually in the UK one injection every 3 months. This is intended to keep your level up, to maintain all the gains of the loading dose. There is the assumption that the loading dose made you better, and then the maintenance dose keeps you better, no matter the cause of the original deficiency, no matter the original level and most importantly to us: no matter the range, severity and frequency of your symptoms and how that impacts on your life.
It really seems unlikely that we would all respond in the same way to the same frequency, doesn't it ? That we would all quickly return to our normal selves - and that this situation could be maintained from then on indefinitely with just 4 injections a year ?
The guidelines advise GPs that someone with B12 deficiency who has neurological symptoms should have every other day injections until no more improvements can be gained by this. Then 1 injection every 2 months as a maintenance dose... 6 injections a year. But how do GPs recognise when a patient has plateaued ? Nerve damage can take a long time to heal, the effects are not always visible or easily measured, and yes, sometimes, some damage can be permanent if left untreated or undertreated. Yet this advice is not widely acted upon by GPs. It is rare to find anyone here who has had this course of treatment, yet many here have presented with obvious neurological symptoms initially.
A GP should not wait for a patient to be seen by a neurologist before starting this B12 frequency. That could lead to further damage occurring. The waiting time is long, several months.
A GP that wishes to help a patient found to have B12 deficiency should also be looking at what else might be going wrong. The usual "other issues" seem to be low folate, low ferritin, low vitamin D and thyroid problems -and so all these should be checked, treated if necessary and monitored. BUT B12 FIRST.
There might be an obvious link to pernicious anaemia: a strong family history of PA and/or other autoimmune conditions for example. There could be a medical or dietary cause. Or both. Or all three. But if no-one asks or looks ...
A better GP might want to treat the patient as an individual with an individual set of B12 deficiency symptoms that can change in range, severity, frequency. The closer a patient can get to how they were prior to deficiency, the better surely: a clear aim.
There can be a good reason for retesting B12 after B12 injections have started, but it is not generally advised. My GP had my serum B12 retested and my serum MMA tested: as she suspected, I had functional B12 deficiency, a diagnosis confirmed by the testing laboratory, which means that high levels of both in the bloodstream are due to them not making the connection necessary to transport the B12 to cells and tissues. This means that although my B12 level was high in my blood, it was staying in my blood: useless to me. I was started on 2 injections a week immediately.
Without also measuring my MMA, based on retesting my B12 only, it would of course have been assumed that I was doing well.
If you are suffering badly with B12 symptoms, it would be wise to have injections every other day until the symptoms subside. You may need them more often than every 3 months for maintenance after that. Many of us here need it more often. Ideally you would want to stay symptom-free.
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