Blood tests

[Polly2501]

Hi everyone, I'm new to this forum and just wanted some advice if that's ok. I was diagnosed with Hashi's last year and before Christmas I was feeling lots better as my medication seemed to be at the right level. For the last month or so I've been feeling pretty awful again. Main symptoms are fatigue, weakness, foggy brain, mood swings and dizzy spells. I've had my thyroid bloods redone and I'm in the range now so the doctor has done some more blood tests to test for other auto immune diseases. I wondered what I should be looking out for in the results if I have pernicious anaemia? I've looked back at old bloods and I tested positive for parietal cell antibodies, could that be a pointer to it? Sorry for the waffling, just wondered if I should mention this to the GP? Thank you.

[Gambit62 Administrator]

Unfortunately GPA isn't a particular test and not is no longer recommended as a diagnositic tool for PA but it probably is worth mentioning it - IFA the other test - is also problematic and comes back with false negatives about 50% of the time so a negative doesn't really rule out PA. There are other absorption problems that can lead to a B12 deficiency - which is what the GP will be looking for.

Diagnosing a B12 deficiency will involve

a) looking at symptoms - overlap with thyroid and other conditions can make this difficult

b) serum B12 test - but the ranges set for this are such that just going by the range is going to result in missing about 25% of people who are actually deficient ... and going to identify 5-10% of people who don't have a problem as having a problem.

c) there are a couple of other tests that can help with clarifying what is going on with B12 at the cell level - MMA and homocysteine - but these can be elevated by other things so aren't first line tests and probably won't have been included in the tests your GP has done

d) signs of macrocytosis - enlarged and slightly rounder blood cells than normal - eg raised MCV and MCH - but macrocytosis is a symptom of B12 (and folate) deficiency not a defining characteristic and isn't among the first symptoms to appear in at least 30% of people with B12 deficiency.