Low TTG IgA levels and risk of false negative Celiac results.

[Petal100]

Hi there, 

I have had some ongoing GI (Chronic Loose stools) and mucosal skin issues leading me to visit my GP for further investigation (I have also have already known AI disorders Rosacea and Endo).  The GP suspected IBS, but wanted to rule out IBD. Fecal Calprotectin was normal suggesting IBS rather than IBD.  However, GP also wanted to test for Celiac, which I had never even considered before as a cause of my problems as i thought my GI symptoms were relatively mild for having this conditions.  So for the Celiac testing, I am based in the UK and the NHS have the following system for initial Celiac Tests. 

Initial TTG IgA samples are received and tested

If TTG IgA is LOW <0.2 U/ml reflex testing for Total IgA will be undertaken.  If Total IgA is LOW <0.1 g/L then reflex testing for Gliadin IgG test will be undertaken. If TTG IgA is HIGH (>/= 10 U/ml), then reflex testing for Endomysial IgA will be undertaken as a confirmatory test.

My TTG IgA came back as 0.4 U/ml, which is on the very low end of the "normal range" and just above the cut off for further testing. My question is should I accept this, or should I push my GP to allow testing for the next stages as above ( as they have already dismissed this as "no further action").  I have now done further research on Celiac disease and I am considering I could have a non classical presentation of this.  However, of course I could just accept, but if the GP refuses further tests, I may try a gluton free diet anyway and see if my symptoms improve.  I know that there is a risk of that some celiacs can present with IGa deficiency. 

My other abnormal lab results were a High ESR (28) , Low Ferritin (9) and low VitD and High Bilirubin (29).  I have researched that some of these results could flag up with Celiac disease too. 

Thanks!

[trents]

Low total IGA can cause false negatives, such as a negative tTG-IGA. When total IGA is low an IGG is often run. I think you do need to find out if your total IGA is low since if it is other conclusions cannot be drawn.

It also sounds like you might have NCGS (Non Celiac Gluten Sensitivity) which has many of the same symptoms but for which there is no test. NCGS does not damage small bowel villi and therefore throws no inflammation antibodies. celiac disease must be ruled out first before a diagnosis of NCGS is arrived at. So, you might also look at an endoscopy/biopsy (the gold standard for diagnosing celiac disease). The antidote would be the same, total avoidance of gluten for life. Whatever you do, if you intend to pursue more testing for celiac disease, you must be eating regular amounts of gluten pre test. Don't start the gluten-free diet until all testing for celiac disease is done.

[knitty kitty]

@Petal100,

Have you been checked for Diabetes?  Endometriosis and rosacea have been linked to diabetes.  

I have all three plus Celiac.

 

[Petal100]

8 hours ago, knitty kitty said:

@Petal100,

Have you been checked for Diabetes?  Endometriosis and rosacea have been linked to diabetes.  

I have all three plus Celiac.

 

Thanks for your reply.  Diabetes has been ruled out.  I have had several blood tests over the years including just recently and my levels are always well under for diabetes or pre-diabetes diagnoses.   Sorry you also have endo, rosacea and celiac,  I guess lots of auto immune problems go hand in hand, which is why I am now considering whether I could be non classical Celiac too!  Just a side note, I use Soolantra cream for my Rosacea and its amazing, really recommend if you have not already tried it.