Ema Test Results Interpretation

[Nannu]

Hi,

Can someone here please help me interpret these results of EMA antibodies. There is another test ordered by doctor which is EMA (IFA technique) for which the report is still awaited:

what kind of reporting happens in IFA technique?

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| ENDOMYSIAL ANTIBODY, IgA IN |

| DILUTIONS |

| (IFA) |

| |

| ENDOMYSIAL ANTIBODY Positive |

| TITRE 1:10 Positive |

1:20 Weak Positive

1:40 Negative

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Thanks a lot in advance. Really appreciate the responses.

Nannu

[Skylark]

When EMA is tested, they dilute the blood serum and look for a response in the assay. The more they can dilute the serum and still get a response, the more antibodies there are. Your daughter had enough antibodies to be positive in the test at 1:10 and weakly positive at 1:20. Normal people do not show any results at 1:10.

IFA stands for immunofluorescence assay. There is some info in this article.

https://www.celiac.com/articles/57/1/Interpretation-of-Celiac-Disease-Blood-Test-Results/Page1.html

The EMA means your daughter's TTG is probably still from a celiac autoimmune reaction. I know you have wheat, rye, and barley well controlled. Is there any chance she is getting exposed to oats? Is she eating gluten-free breads made in a facility that could have oat CC?

[Nannu]

When EMA is tested, they dilute the blood serum and look for a response in the assay. The more they can dilute the serum and still get a response, the more antibodies there are. Your daughter had enough antibodies to be positive in the test at 1:10 and weakly positive at 1:20. Normal people do not show any results at 1:10.

IFA stands for immunofluorescence assay. There is some info in this article.

https://www.celiac.com/articles/57/1/Interpretation-of-Celiac-Disease-Blood-Test-Results/Page1.html

The EMA means your daughter's TTG is probably still from a celiac autoimmune reaction. I know you have wheat, rye, and barley well controlled. Is there any chance she is getting exposed to oats? Is she eating gluten-free breads made in a facility that could have oat CC?

Hi Skylark,

Thanks for writing. I understand that test confirms that celiac condition is there. Having said that, do you think this test anyway signifies that antibodies could be coming down. Her TTG levels at the time of diagnosis were 297, then 291 and now 296. These results, do they conclusively confirm that she is ingesting gluten or is any other issue? Regarding oats, i will crosscheck, but i guess oats is not being ingested and also no bakery products are being brought from outside.

Thanks

Nannu

[Skylark]

Hi, Nannu

You can't directly compare TTG and EMA. They are completely different sorts of tests. Did your daughter have EMA before?

I was also wondering what the limit of quantitation is on the TTG test? You may have to ask the lab. Your daughter's numbers are quite high and I'm wondering if you're so close to the top of the test that you're not seeing a drop? I mean what if her real number had started at 500 and read 290 and now it's 300 and still reading 290? You would probably have to find this out from the diagnostic lab running the test.

[Nannu]

Hi, Nannu

You can't directly compare TTG and EMA. They are completely different sorts of tests. Did your daughter have EMA before?

I was also wondering what the limit of quantitation is on the TTG test? You may have to ask the lab. Your daughter's numbers are quite high and I'm wondering if you're so close to the top of the test that you're not seeing a drop? I mean what if her real number had started at 500 and read 290 and now it's 300 and still reading 290? You would probably have to find this out from the diagnostic lab running the test.

Skylark,

Thanks again. What do you mean exactly? I feel this lab is able to read the numbers upto 300 atleast. Mine has always been below 300. I guess i didn't understand your question well.

[Skylark]

Tests have a ceiling, above which the numbers are unreliable. It's called the limit of quantitation. I don't now how to explain any better. Say the test only goes to 300ish. What if your daughter's "real" TTG readings were 500, 400, and 300, but the test keeps reading 300ish because it is at the limit of quantitation.

Think of a car speedometer. It has a maximum. Even if you're on a racetrack going really fast, your speed will look like the maximum the speedometer can read. You can't tell anything about how much faster you are going. Assays work like this too. I don't know for sure that it's what happening - I may be totally wrong - but it's worth looking into.

[Nannu]

Tests have a ceiling, above which the numbers are unreliable. It's called the limit of quantitation. I don't now how to explain any better. Say the test only goes to 300ish. What if your daughter's "real" TTG readings were 500, 400, and 300, but the test keeps reading 300ish because it is at the limit of quantitation.

Think of a car speedometer. It has a maximum. Even if you're on a racetrack going really fast, your speed will look like the maximum the speedometer can read. You can't tell anything about how much faster you are going. Assays work like this too. I don't know for sure that it's what happening - I may be totally wrong - but it's worth looking into.

Thanks for explaining Skylark. I have registered a request at the lab to get a clarification on this. Lets hope that they get back.

Thanks again.

Nannu

[Nannu]

Hi Skylark,

Lab confirmed that their ttg testing can detect even higher values and that these are actual numbers.

Will keep updating.

THanks

Nannu

[Skylark]

Ah, well. It was worth looking into.