I've been pursuing PA as a possible explanation for my numerous long term health issues, beginning injections on 6/3. As many here report, results have been mixed; apparent initial improvement followed by some issues worsening. I understand the mechanism of PA is presence of an antibody against Intrinsic Factor, which is required to absorb B12 orally. My understanding is that, like most medical testing, determining if that antibody is present is not a prefect process. What are the best current recommendations for testing to determine PA? I began this process after my B12 & blood count levels suggested PA, and I certainly have symptoms consistent with this diagnosis, and have had for some time. I still feel PA is a very likely cause, but I have a Dr's appointment this Friday & plan to request PA testing. I'd like to know what THE BEST testing in that regard would be. Thanks!
State of the art testing for PA? - Pernicious Anaemi...
State of the art testing for PA?
I should add that I'm in the US (Washington state).
Referring to your heading , I’m
afraid that there is unfortunately no “State of the Art “ testing for Pernicious Anaemia.But firstly as you say , your symptoms are the first clues . Secondly your blood serum reading of B12 ( But this is not fool proof )
The Intrinsic Factor Antibody test is unreliable if you test negative . But if you test positive , it’s pretty certain that you have P.A.
Homocysteine levels can also be a help, but other conditions also cause high levels.
MMA ( Methyl Melonic Acid Test) both blood and urine ) can also indicate P.A. These are more expensive tests
Also bear in mind that if you do have PA . that it is an auto-immune condition , and as such rarely comes alone . Other autoimmune conditions often accompany PA . Thyroid conditions seem to be the most common to accompany PA . I, for instance, have Rheumatoid Arthritis as well , but there are other possibilities . This is one of the reasons why PA can be difficult to diagnose , as many conditions that can accompany it can have overlapping symptoms .
If you have PA , lack of stomach acid can give you gut problems like stomach pains , constipation or diarrhoea and bloating .
Enlarged red blood cells can be present in PA , but not always .
So in the first instance, the unreliable blood serum test ( IFA Test ) should be tried .You have a 50% chance of an accurate outcome ! I was lucky and got a positive test to prove PA .
I wish you the very best for your Friday appointment , and hope you have a doctor who is well-informed on PA . They are not easy to find in the U.K. .If “Big Pharma “ were involved it would be different . But B12 is “only a vitamin “.
Hi,
Some links that might be useful.
Some info may be UK specific so units and ranges for blood tests may be different to US.
Link about "What to do next" if B12 deficiency suspected
b12deficiency.info/what-to-...
PAS (Pernicious Anaemia Society)
Based in Wales, UK. Has members in other countries.
pernicious-anaemia-society....
PAS tel no +44 (0)1656 769717 answerphone
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.
Both these tests can be unreliable.
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.
B12 Deficiency Info website
B12 Awareness (US website)
Stichting B12 Tekort (Dutch website with English articles)
stichtingb12tekort.nl/weten...
UK B12 Blogs
Martyn Hooper's blog about PA
B12 Deficiency Info blog
Blood tests
b12deficiency.info/b12-test...
Macrocytosis
patient.info/doctor/macrocy...
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...
Symptoms of B12 Deficiency
pernicious-anaemia-society....
b12deficiency.info/signs-an...
Risk Factors for PA and B12 Deficiency
pernicious-anaemia-society....
b12deficiency.info/what-are...
b12deficiency.info/who-is-a...
Coeliac Blood Tests
coeliac.org.uk/coeliac-dise...
UK guidelines suggest anyone with unexplained b12, folate or iron deficiency should be tested for Coeliac (spelt Celiac in US).
H Pylori infection?
patient.info/digestive-heal...
Any chance of internal parasites eg fish tapeworm? Do you ever eat raw fish?
Giardia Lamblia is another parasite that can lead to b12 deficiency.
Exposure to nitrous oxide?
ncbi.nlm.nih.gov/pmc/articl...
onlinelibrary.wiley.com/doi...
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).
"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".
I am nor medically trained.
The best way of diagnosing PA is to rule out all other causes of a B12 deficiency.
First off, you need to determine is you have a deficiency. You can do various blood tests (serum B12, Active B12, MMA, hCys). But the best way of diagnosing a B12 deficiency is - Do you have the right symptoms and do those symptoms go away when you have B12 injections.
Assuming you do have a B12 deficiency. What might cause it? Are you vegetarian or vegan, do you take PPIs or metformin, do you abuse nitrous oxide, have you had surgery on your gut, do you have coeliacs? If the answer to all of those is 'no' then you probably have PA.
You can do a final check by testing for antibodies to both Intrinsic Factor and Gastric Parietal Cells. If the first is positive then you almost certainly have PA. If negative, it is meaningless. If the second is negative then you probably don't have PA, if positive then you might have PA.
You can also look for signs of the underlying cause of PA - Autoimmune Metaplastic Gastric Atrophy. A gastroscopic examination will, if you have AMGA, show atrophy of certain areas of the stomach lining. Microscopic analysis of biopsy samples will show signs of metaplasia (the wrong sort of cells). Examination of the blood will show high levels of the hormone gastrin.
I got my diagnosis of PA from my idiot haematologist. Originally he said that I didn't have it - based solely on the fact that I hadn't had the IF antibody test. Not that the result was negative - just that I hadn't had it! He changed his mind when I asked him to explain a serum B12 of less than 64 pmol/L, positive response to B12 injections, Positive GPC antibodies, gastric atrophy, metaplasia and high gastrin.
Thanks all for the replies, very helpful. I see these tests can be either via immunofluoresence or ELISA. Should I push for ELISA, or is this now the standard? Here's an interesting piece: ncbi.nlm.nih.gov/pubmed/227...
Those tests are for antibodies to Gastric Parietal Cells. That is no longer recommended as a test for PA because it produces too many false positives.
Testing for antibodies to Intrinsic Factor should all be done by ELISA nowadays. The test first became commercially available back in 2007, replacing the RadioImmunoAssay that was used before. The RIA test was pretty useless as it could give false positives if high levels of B12 were present. So you had to stop supplementing for months before being tested. The ELISA test is much more forgiving.
fbirder - Thanks for the reply. You had said "You can do a final check by testing for antibodies to both Intrinsic Factor and Gastric Parietal Cells." What are the details (specific test names, etc) of the current best means of doing this? Any literature supporting those specific test's validity would be great. Thanks.
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