Newly diagnosed with pernicious anemi... - Pernicious Anaemi...

Pernicious Anaemia Society

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Newly diagnosed with pernicious anemia, still have unresolved symptoms


Hi everyone! I'm quite new here, and was just diagnosed with pernicious anemia (somewhat--more later) a month ago.

I essentially had overwhelming fatigue for several months, to the point where I finally realized it must be a medical situation. When I went to the GP, she tested my B12 levels (as I'm a vegetarian), and I was somewhat deficient (level around 200). We both thought this was odd because I take B12 oral supplements daily. When tested, I tested negative for anti-parietal antibodies, but positive for intrinsic factor antibodies. My GP then informed me I would need to take sub-cutaneous injections for once every two weeks after initially taking injections once daily for a week. I don't know if I can call what I have pernicious "anemia" because my red blood count was normal, and my GP said there was nothing to indicate anemia, and that we had caught it due to the B12 deficiency and it had not turned to anemia.

I have taken a week's worth of B12 injections, and do not feel like my fatigue levels have improved much. I'm still quite tired, I still get out of breath after very little activity and cannot exercise. I also feel like I lose my train of thought quite easily (much more so than before). Some of my minor symptoms seemed to have resolved--I no longer have random muscle spasms, and I no longer have cracked corners of my lips, which is great, but they were not my primary issues.

I also have experienced weight gain (~10-15lbs over the last 6 months) and am eating less than ever. My doctor has dismissed this out of hand, and claims that I must be eating more than I realize despite counting calories rigorously and sticking to 1200 a day. My TSH levels are normal, so she said it couldn't be my thyroid.

I'm wondering how long B12 injections take to work in someone only mildly deficient? I'm also wondering if there's anything that accounts for weight gain? I'm visiting a hematologist in a month's time, and I want to make sure I ask the right questions, if possible.

Thanks everyone for the help!

5 Replies


It is very late here so no answers from the 'experts' until tomorrow.

Are you in the UK, you sound as if you are, but the treatment from you GP sounds a bit strange, and are not following the NHS guidelines. You will find these pinned on the right hand side.

I suggest you get printouts of your blood tests from your surgery (you are entitled by law to have them) and post them on here. Doctors, sometimes dismiss or call things normal when they are not.

When tested "positive for intrinsic factor antibodies" you have Pernicious Anaemia.

I'm sure this will be explained by the 'experts'.


Presumably you aren't UK based.

PA is actually an auto-immune condition in which the gut attacks the mechanism that allows you to absorb B12 from your diet - it is the most common cause of non-dietary B12 deficiency and being IFA positive is a good indicator that you are B12 deficient (unless you had taken high dose B12 supplements just before the test). Even if it had come back negative PA is the most likely cause of your deficiency.

Anaemia isn't necessarily one of the first symptoms to appear - and isn't present in 25% of people who first present with B12 - you can be very badly affected by B12 deficiency without having any signs of anaemia. If you are also having problems absorbing iron then the iron deficiency can mask B12 deficiency and make interpreting blood test results extremely difficult.

Resolution of symptoms can take a while and some people do actually feel worse before they feel better - immune system kicking in so more reaction to infections and the aches and pains can get worse for a while. Some symptoms resolve quickly and some take much longer


Some links that may be of interest.

B12 books I found useful

"What You Need to Know About Pernicious Anaemia and B12 Deficiency" by Martyn Hooper

Martyn Hooper is the chair of PAS (Pernicious Anaemia Society). Book is up to date with UK b12 guidelines.

"Living with Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Has several case studies.

"Could it Be B12?: An Epidemic of Misdiagnoses" by Sally Pacholok and JJ. Stuart (USA authors)

Very comprehensive with lots of case studies. There is also a pediatric version of this book aimed at parents.

PAS (Pernicious Anaemia Society)

Based in Wales, UK. Has members in other countries.


PAS tel no +44 (0)1656 769717 answerphone

B12 Deficiency Info website

B12 Awareness (USA website)

Stichting Tekort (Dutch b12 website, has English language articles)

More B12 info in pinned posts on this forum.

I am not medically trained.

Thanks all! I'm US-based, but I can't seem to find a US-based support group. Does everyone find that they still struggle even when they have "enough" B12, or after several months of treatment?

Your symptoms could easily be from hypothyroidism, which frequently occurs along with PA.

A normal TSH doesn't preclude thyroid disease. The range for TSH in the US is too wide-- anything up to 5.0 is "within range", but people can have hypothyroid symptoms over 2.0.

If you are having hypothyroid symptoms, then you should have more than just a TSH screening test. You should have TSH, free-T3, and free-T4 at a minimum, and possibly reverse-T3 and thyroid antibodies (ATA, TPO). You might need to find another doctor to run the tests, if your GP is reluctant. Or you can order the tests for yourself online if you don't mind paying for them out-of-pocket. has more details on thyroid disorders. I find the website a bit chaotic to read, but it does have good information.

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