How is PA diagnosed?: Hello everyone... - Pernicious Anaemi...

Pernicious Anaemia Society

32,669 members24,064 posts

How is PA diagnosed?

15 Replies

Hello everyone!

I've found my way here from the TUK boards.

I have recently discovered I have Hashimotos thyroiditis. I'm having full blood count and iron panel in 2 weeks to look for PA, among other things, but I can't find anything really about how it's diagnosed in terms of blood tests and ranges. Is it based solely on B12 results?

Read more about...
15 Replies
Nackapan profile image
Nackapan

The intriscic factor antibody test can be done.

If the result is positive you have PA.

If negative it doesnt rule out PA

Other than that Mma and homocysteine blood tests

None of them definitive clinical diagnosis are sometimes made.

If you look through posts /topics some can give a much clearer explanation.

Also serum b12 /folate tests done first. Also a guide as it gives the total of b12 in the blood .

An active b12 usually not done by the NHS also available.

Symptoms ,low b12 and response to treatment. Some if dietary will respond well to oral forms of b12

Nackapan profile image
Nackapan

PAS have good fact sheets on this

fbirder profile image
fbirder

The first step is to determine if a B12 deficiency is present. This should start with a serum B12 test. If you are below the bottom of the 'normal range' then you definitely have a deficiency and can proceed to the next step. If you are well above the bottom on the normal range then you almost certainly do not have a deficiency. If you're in the grey area between then there can be problems.

There's a big overlap between people who are deficient, but have 'normal' levels of B12 and people who are aren't deficient but have below 'normal' levels. See my explanation here - b12science.com/B12Science/D... If you do fall in that grey area then you have to try and persuade your doctor to diagnose you as deficient based on your symptoms. Or to give you a trial of B12 injections.

If you are deficient then the next hurdle is to determine the cause. The first step is the Intrinsic Factor antibody test (IF is the protein needed to carry B12 from the gut to the blood). Unfortunately, only about half of all people test positive.

If you test negative then it doesn't mean that you don't have PA. It does mean you may find it hard to get a diagnosis.

If you eat lots of meat/fish then you will be getting plenty of B12 in your diet. If you're vegetarian or vegan then it's possible (very likely if vegan) that you're not eating enough B12. If that's the case then low-dose tablets might fix your deficiency.

If it's non-dietary and you do not take metformin (for diabetes) or PPIs (for stomach acid) and you haven't have gut surgery, and you do not have a disease like coeliac's or Crohn's, then it's a near certainty that you have Pernicious Anaemia.

Nackapan profile image
Nackapan in reply tofbirder

That graph is interesting.

I thought I was definitely deficient with a serum b12 test of 106ng/l. So even at that level some are well .

One Gp said at the time he thought the b12 was a red herring. This still Haunts me. When I asked him on another consult what he meant. He said he had no idea!! Nothing else has been found wrong with me .

I'm having one of those doubtful days of will I get to function better.

Thay graph has such a crossover

fbirder profile image
fbirder in reply toNackapan

The graph is symbolic of the actual situation. The curves aren't meant to represent actual numbers.

Nackapan profile image
Nackapan in reply tofbirder

Oh okay . I'm being too literal again looking at things. Thanks

Nackapan profile image
Nackapan in reply toNackapan

I will put my ruler away !

fbirder profile image
fbirder in reply toNackapan

My bad.

I've removed the numbers on the X-axis. I really don't know why I put them there.

Nackapan profile image
Nackapan in reply toNackapan

P.s I switched to another G.p in the practice as he was the one that wanted to stop my b12 injections as having a 'bad reaction' Also said the parietal cell test I had was negative was definitive of a dietary deficiency. I dud say it wasnt ad I ea4 mes4 fush diary ect. I didnt know at the time this test not used now I was never given an intrinsic factor antybody test. I always look into things again and again to try and move forward. Feeling quite stuck again .

in reply tofbirder

So it goes on Serum B12 and not ActiveB12?

We are veggie/vegan so it is most likely dietary but my Active B12 was higher when I was vegan than it is now that we're more veggie.

My serum B12 always looks adequate but active looks terribly low.

06/09/17 - B12 - 497 (200 - 960)

04/06/19 - Total B12 - 250 (300 - 569)

28/11/19 - B12 - 413 (200 - 960)

04/06/19 - Active B12 - 51.7 (37.5 - 188)

22/06/20 - Active B12 - 45 (37.5 - 188)

🤔

I'd appreciate your thoughts.

I'm waiting until after my bloods at the Drs to start taking a B12 supplement in case I skew the results!

fbirder profile image
fbirder in reply to

Most doctors are unaware of the existence of 'Active' B12, or the tests for it. The ranges for both should be set to catch most deficient people.

Normally, you'd expect Active B12 to be about one-quarter to one-fifth the total B12. So your values from June '19 look about right. The fact that your Active B12 has dropped over a year may be significant.

Although the serum B12 test isn't accurate (results from the same sample can vary by more than 10%) I believe that the Active test is better in that regard, so a drop from 52 to 45 over 12 months is likely to be real - and probably indicative of an absorption problem. So a total B12 of less than 300 wouldn't be a surprise.

in reply tofbirder

Thank you for that. It's very much appreciated. It's a job to know what I'm looking at sometimes!

Sleepybunny profile image
Sleepybunny

Hi,

Link about "What to do next" if B12 deficiency suspected or newly diagnosed.

b12deficiency.info/what-to-...

Risk Factors for PA and B12 Deficiency

pernicious-anaemia-society....

b12deficiency.info/what-are...

b12deficiency.info/who-is-a...

Have you ever been tested for PA?

PAS (Pernicious Anaemia Society)

Based in Wales, UK.

pernicious-anaemia-society....

There is a helpline number that PAS members can ring.

PAS support groups in UK

pernicious-anaemia-society....

Blog post about how PAS can support PAS members seeking PA diagnosis

martynhooper.com/2017/06/24...

PA tests

Intrinsic Factor Antibody (IFA) test

labtestsonline.org/tests/in...

Parietal Cell Antibody (PCA) test

labtestsonline.org/tests/pa...

PCA is not recommended as a diagnostic test for PA in UK.

It is still possible to have PA with a negative result in IFA or PCA test.

About 50% of people with PA test negative on IFA test.

About 10% of people with PA test negative on PCA test.

Coeliac Disease?

In UK, two first line tests are recommended.

1) tTG IgA

2) Total IgA

If you've been tested in past, check both tests were done.

NICE guidelines Coeliac Disease suggests anyone with unexplained B12, folate or iron deficiency should be tested.

nice.org.uk/guidance/ng20/c...

Coeliac Blood Tests

coeliac.org.uk/coeliac-dise...

H Pylori infection?

patient.info/digestive-heal...

NICE guidelines H pylori

pathways.nice.org.uk/pathwa...

Click on blue boxes in flowchart for more info.

Exposure to Nitrous Oxide

gov.uk/drug-safety-update/n...

NICE guidelines Nitrous Oxide ( see side effects section)

bnf.nice.org.uk/drug/nitrou...

Any possibility of internal parasites eg fish tapeworm?

I wrote very detailed replies on another forum thread with links to B12 deficiency symptoms lists, B12 books, B12 websites, UK B12 documents and other B12 info which you might find helpful.

healthunlocked.com/pasoc/po...

If you're in UK, be aware that the pandemic is impacting patients' B12 treatment.

Many UK forum members have reported injections being stopped/delayed

/frequency reduced or swapped for oral tablets.

I left a detailed reply about impact of pandemic on B12 treatment in UK in next link.

healthunlocked.com/pasoc/po.....

I am not medically trained.

in reply toSleepybunny

Thank you! I'll read the links later on. Very much appreciated.

Never tested for PA. Was tested for Coeliac's in 2013 which was negative but they only did one of those tests.

Both PA and coelics being tested in a couple of weeks. I am just trying to get ahead of any possibilities to prepare myself.

Thank you!

Sleepybunny profile image
Sleepybunny in reply to

Hi,

"Both PA and coelics being tested in a couple of weeks"

If you're in UK, I suggest reading the NICE guidelines on diagnosing Coeliac disease. See link in my other post.

They suggest that before blood is taken, people should eat gluten in more than 1 meal every day for at least 6 weeks before testing. Has your GP told you to do this?

If a patient, who has Coeliac disease, is not eating enough gluten before blood taken, the TTG IgA test is likely to come back negative because there are not enough antibodies to gluten in the blood.

Are they going to do the Total IgA test?

This is important because people with IgA deficiency need different tests for Coeliac disease.

People who have negative results in Coeliac tests but have symptoms consistent with Coeliac disease should be referred to a gastro enterologist according to NICE guidelines.

Tests for PA

Still possible to have PA even if Intrinsic factor Antibody test has a negative result.

Some GPs and specialists may not be aware that it is possible to have Antibody Negative PA. See flowchart and guidelines below if you're in UK.

UK B12 documents

BSH Cobalamin and Folate Guidelines

b-s-h.org.uk/guidelines/gui...

Flowchart from BSH Cobalamin and Folate Guidelines

stichtingb12tekort.nl/weten...

Flowchart outlines a process for diagnosing PA and Antibody Negative PA in UK

BMJ B12 article

bmj.com/content/349/bmj.g5226

Emphasises need to treat patients who are symptomatic even if their B12 level is within range.

BNF ( UK Guidance for treating B12 deficiency)

bnf.nice.org.uk/drug/hydrox...

BNF guidance on treating b12 deficiency changed last year.

pernicious-anaemia-society....

NICE CKS

cks.nice.org.uk/anaemia-b12...

I recommend doing some homework on B12 deficiency before appointments as sadly many GPs and specialists have not done theirs.

I spent many years desperately seeking answers for my ill health and so many GPs and specialists missed typical symptoms of B12 deficiency. I consider myself lucky to have avoided dementia and spinal damage as at one point I had both dementia type symptoms and pins and needles in my spine.

Blood tests

b12deficiency.info/b12-test...

Macrocytosis

patient.info/doctor/macrocy...

GPs and specialists often look for signs of macrocytosis in someone with suspected B12 deficiency.

Some forum members have been told they are not B12 deficient because they do not have macrocytosis.

You may need to challenge them if you're told this as many people with B12 deficiency do not have macrocytosis. See info about macrocytosis in BSH Cobalamin and Folate Guidelines.

Full Blood Count and Blood Film

labtestsonline.org.uk/tests...

patient.info/doctor/periphe...

Folate Deficiency

patient.info/doctor/folate-...

Iron Studies

labtestsonline.org.uk/tests...

Other B12 websites

B12 Deficiency Info website

b12deficiency.info/

B12 Awareness (US)

b12awareness.org/

B12d.org holds support meetings near Durham, UK

b12d.org/event

Stichting B12 Tekort (Dutch website with English articles)

stichtingb12tekort.nl/weten...

Units of measurement and reference ranges may vary from those in UK.

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). BNF info in book is out of date. See BNF link up page.

"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 paediatric version of this book "Could It Be B12? Paediatric Edition: What Every Parent Needs to Know".

"Vitamin B12 deficiency in Clinical Practice" (subtitle "Doctor, you gave me my life back!" by Dr Joseph Alexander "Chandy" Kayyalackakom and Hugo Minney PhD

Consequences

There can be severe consequences if B12 deficiency is untreated or under treated including the possibility of damage to the spine.

Neurological Consequences of B12 Deficiency

PAS news item

pernicious-anaemia-society....

PAS article about SACD, sub acute combined degeneration of the spinal cord, access to PAS members only.

pernicious-anaemia-society....

Blog post from Martyn Hooper's blog, mentions SACD

martynhooper.com/2010/09/21...

B12 article from Mayo Clinic (US)

ncbi.nlm.nih.gov/pmc/articl...

Suggests

1) No proof that oral b12 is a good at treating B12 deficiency as B12 injections

2) Many current diagnostic tests eg serum b12, active B12, MMA, Homocysteine, are not always effective at diagnosing B12 deficiency.

3) Successful treatment should not be stopped

Unhappy with Treatment (UK info)

Letters to GPs about B12 deficiency

b12deficiency.info/b12-writ...

Point 1 is about under treatment of B12 deficiency with neuro symptoms.

CAB NHS Complaints

citizensadvice.org.uk/healt...

MPs and devolved representatives in Wales, scotland, NI may be worth talking to if struggling to get recommended treatment in UK.

Do you have any neurological symptoms?

If yes , have you been referred to

1) a neurologist

2) a haematologist

Not what you're looking for?

You may also like...

How is PA diagnosed?

How is PA diagnosed? How do we know if we have it?? I don’t think I have it but I do need to keep...

Recently diagnosed with PA

Hi my name is Nikki and I am 24 years old, in the last few weeks I have been diagnosed with...
Nikkimae profile image

Recently diagnosed with PA

I’m just back from GP, I am due my final loading dose this afternoon, my GP said I will then have...
Melie3 profile image

How likely is it I have PA

Hello, I would appreciate some feedback on your own experiences of diagnosis. - 3 months ago I...
Sparkleros profile image

PA???

I had a MMA blood test to check my B12 levels this was in January 2019, I was using a B12 spray...
Jan87 profile image

Moderation team

See all
Gambit62 profile image
Gambit62Administrator
Foggyme profile image
FoggymeAdministrator
taka profile image
takaAdministrator

Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.

Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.