Does anyone know if a urine MMA test is more accurate than a blood MMA please?

[Jo5454]

Hi, I wonder if anyone can help please?

I had a MMA blood test last year ( via St Thomas) as a follow on from Active b12 test. I'm wishing to do a retest, but will have to pay as my dr prefers not to get involved in case it affects the frequency of my injections. My symptoms are returning prior to my monthly injections and the further I get from my initial dose seem to lack their potency?

So I'm thinking of checking with an MMA test and have read some older questions that state urine test is actually more accurate than blood and Just wondering please if

- this is still the case with current testing methods?

-why is urine more accurate, a post indicated it is more helpful in people with neurological symptoms?

Many thanks, any ideas appreciate Don't!

[Gambit62 Administrator]

MMA can be raised as a result of various things involving kidneys etc as well as B12 deficiency.

My understanding is that it is easier to assess whether there are other factors involved in the test is done on urine than it is if it is done with a blood sample

[Jo5454 in reply to Gambit62]

Thanks gambit62

[fbirder]

If they do a urine test then it's easy to check for kidney function using the same sample. If they use blood then a high level of MMA would require a separate urine check for kidney function.

[Jo5454 in reply to fbirder]

Thanks fbirder. I had a level checked for kidneys via the blood test before they'd do a MMA before...is that the check you mean or would the urine test be for kidney function be more detailed?

Thanks.