B12 active test for P.A?

[Thyroid1892]

Hi, I’ve previously had a B12 serum test (suspected b12 deficiency) from my gp which has come back normal. P.A runs in my family and I’m very symptomatic. I’m looking at getting some private tests done but am a bit confused if anybody can help?

I have seen that for some people who suspect pernicious anemia the intrinsic antibody test is useful for further diagnoses, but that test is almost double the price of active b12 test. Also, I’m just looking for some sort of confirmation of a deficiency really, so I can self inject. I’m not too concerned about the diagnostic reasons for what’s potentially causing it (antibodies etc).

So essentially what I’m asking is, if it is indeed P.A, can a b12 active test alone give me confirmation of a deficiency? Sorry for rambling haha. Cheers.

[fbirder]

An active B12 test can tell you if you may be deficient. It’s very similar to the serum test you’ve already had but some people think it is more accurate. What it won't do is tell you if you have PA or if the deficiency is caused by something else.

Personally, I would go for Viapth’s ‘My B12’ test at £60. You get the serum and active B12 tests plus MMA (a compound used up in one of the reactions mediated by B12 - high levels of MMA indicate insufficient B12 getting into the cells).

[Thyroid1892 in reply to fbirder]

Thank you for this. In my gp testing my folate was slightly low with normal b12, not sure if low folate means anything?Could you potentially get a normal result from an active b12 test and still have P.A? If so is the MMA result usually reliable for deficiency diagnoses or can that also normal with P.A also?

I’m a student and pretty low on funds haha and just want to make sure the test I choose is the right one.

Thanks in advance.

[Targetgrow in reply to Thyroid1892]

Do you know what level your "normal" serum B12 result was?

[Thyroid1892 in reply to Targetgrow]

Hi, I’ve lost the results sheet haha. But I believe they weren’t on the lower end of normal, they were just right in the middle. The thing is, my mum had testing done for years when she was younger and was told her levels were normal, whilst she suffered for years with symptoms until she was later told she was finally anemic. That’s why I’m looking for a private test really. Whatever is cheapest and most accurate to just let me know I’m deficient. If in deed I am. Thanks.

[fbirder in reply to Thyroid1892]

Low folate can be caused by absorption problems. But it's more commonly caused by a diet lacking in folate-rich foods (leafy green veg and the like).

If you have PA then a normal Active B12 test isn't likely. But not impossible.

The MMA test isn't specific for PA. But a positive result means that a B12 deficiency is one of the possible causes. It is also possible to have PA with normal MMA.

Try going to the GP and asking for active B12, MMA and IF (Intrinsic Factor).

[Thyroid1892 in reply to fbirder]

I’ve asked my GP about these tests to which he says aren’t available. You said there about P.A and active b12 test do you mean if you have P.A then an active b12 test result coming back normal is unlikely? Because I saw a £40 test for active b12, and tbh that’s my budget at the moment, and if this is generally an accurate test for deficiency I’m tempted to just get that. What do you think? Cheers.

[fbirder in reply to Thyroid1892]

High active B12 would be very unlikely if you had PA unless it was in the early stages. PA stops B12 from being absorbed and recycled. Once that starts happening then it takes a few years for levels to drop to where symptoms become noticeable.

It sounds like the £40 active B12 test should help settle your mind. However, your GP may ignore it.

[Foggyme Administrator in reply to fbirder]

fbirder ...'High active B12 would be very likely if you had PA unless it was in the early stages'...

Think you mean unlikely...😉

[fbirder in reply to Foggyme]

Indeed, I did. Thanks. Edited.

[Foggyme Administrator in reply to fbirder]

👍

[Thyroid1892 in reply to fbirder]

This is exactly what I needed to hear thank you for helping me! I’m going to self inject anyway if P.A my gp isn’t interested. Thanks again.

[Polaris]

You might find this latest BMJ research document (summary only) interesting Thyroid1892, as it states there is no reliable test and emphasises the importance of history and symptoms. Medicine is very test based nowadays and few GPs understand the complexity of B12. This is why many of us on the forum find it less stressful to self inject:

bmj.com/content/349/bmj.g5226

Another with further links:

medium.com/@martinecotton/1...

Best wishes.

[Thyroid1892 in reply to Polaris]

Thank you for this Polaris, I shall have a look at these documents tomorrow in more depth. Tbh I was initially just going to self inject without testing as I’m convinced I’m deficient. However in the end I come to the conclusion that I’d get the cheapest test done for peace of mind. Save injecting the rest of my life and it turned out it wasn’t P.A haha.