For the past year I've been suffering from bouts of exhaustion and 'brain fog', along with a persistent headache. A few months ago, on recommendation from my sister - who suffers from B12 deficiency - I asked my GP for a test. The results were a reading of 270 ng/l - no "cause for concern" for the doctor.
My condition has got worse recently: last week being horrible. At times the 'fog' and headache was so bad, I found it difficult leaving the house. It feels like I'm drunk, or in a dreamworld.
I'm a pescetarian, although for the last couple of weeks I've had more of a strict vegetable based diet. I'm wondering if this has been the change that has made me feel worse.
Is 270 ng/l a low reading? Also, is the persistent headache a common complaint with B12 deficiency?
Any help would be amazing,
Many thanks!
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JR1980
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I always emphasise any neuro symptoms I have. The treatment for B12 defic with neuro symptoms is more intensive than for those who have b12 defic without neuro symptoms. Info for GP on treatment is in BNF (British national Formulary) Chapter 9 section 1.2. The BNF is copyrighted. It is possible to get your own copy.
I try to find out the reference ranges for blood tests if possible, then it is possible to see if results are above , below or within normal range.
MMA and Homocysteine and Active B12 can provide further evidence of possible B12 deficiency. If you are already supplementing with B12 then further tests may not give you reliable results. It is possible to get these tests done privately.
Another test that is not often done on NHS but can be done privately is a blood film or blood smear. This will show up unusually shaped blood cells.
On the FBC (Full Blood Count) I look closely at the MCV and MCH. High MCV and MCH may indicate the possibility of a macrocytic anaemia. Low iron (ferritin) makes red blood cells smaller, low B12 and/or low folate makes red blood cells bigger. If you have both low iron and low B12 and/or low folate your red blood cells may appear normal size.
It is possible to have two or even three anaemia conditions at the same time eg iron deficiency anaemia, folate deficiency anaemia and B12 deficiency anaemia.
Obviously I don't know if you have these conditions because only a doctor can diagnose this.
Iron deficiency anaemia (makes red blood cells smaller) has the opposite effect to both folate anaemia and B12 anaemia (both of these make red blood cells larger) so Iron deficiency anaemia can cancel the signs of the other two conditions.
If your MCV and MCH are "normal" it is possible that a GP may not realise that you have b12 deficiency anaemia or folate deficiency anaemia.
I found the "BCSH Cobalamin and Folate guidelines" very useful to read. It's a long document but well worth it. I found page 29 a diagnosis flowchart particularly useful.
Sadly there are some Gps and consultants who don't realise that it is possible to have B12 deficiency without macrocytosis.
Hi there new to this site (more on my post re I know if have PA but GP says I don't)
Your B12 is very low, in the "grey zone" ie "normal" but you are getting neurological symptoms. My symptoms are worse that yours (see my post) and the last 2 weeks have been dreadful. My B12 is dropping like a stone an ferritin is 10! I am finally stating on B12 injections but had to fight for it.
If you google British Committee for Standards in Haematology, look at General Guidelines, B12 is up near the top and was updated last year. This UK guideline, and every bit of research I have read, clearly states if you are experiencing neurological symptoms, even if your serum b12 is "normal", you must treat without delay to avoid neurological damage.
Apparently, this test is very inaccurate. You can have symptoms in the "grey zone" (200-450).
Download this and give it to your GP. You need B12 injections without delay. Waiting to <200 is really not advised. GPs just look at lab results and not symptoms. I should know, I am a Practice Nurse!
I am sure someone will correct me if this information is wrong
Thanks for your help, and so sorry to read about your symptoms...I do hope you get some solutions soon.
I took your recommendations to my doctor, who was keen to issue more blood tests. I have the results back, but haven't had a follow-up consultation yet.
My B12 level has risen from 270 to 296 ng/l (190-663) since my last test. This may be to do with supplementation.
However, my Serum Ferritin levels have dropped from 98 to 37 ug/l (30-400) in 6 months. I'm not sure this is normal fluctuation. I'll be asking whether this could be causing the fatigue, headaches and brain fog.
The change in diet is unlikely to be a factor - as B12D would be an absorption problem if you have been eating fish and it came on in that period.
Much more likely that you are getting to the point where the absorption problem is becoming acute and liver stores are now depleting.
The body stores B12 in the liver and then releases it back into your system through bile via the ileum.
If you have a problem in the ileum then this recycling is also going to have become increasingly inefficient as the absorption problem increases (presumably PA - though if anyone tries to rule that out by doing IFA or PCA tests that come back negative - don't listen - both tests are notoriously inaccurate and can be done several times with different results).
As a result it can take years and even decades for an absorption problem to develop into a full blown deficiency though things will tend to accelerate towards the end - and that's probably why the symptoms have seemed to get worse recently.
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