Gliadin (Deamidated) Antibody (IgA) Test
The Gliadin (Deamidated) Antibody (IgA) test measures IgA antibodies that bind deamidated gliadin peptides in a blood sample. It is used in evaluating celiac disease, and Quest describes deamidated gliadin peptide assays as having higher diagnostic accuracy than standard gliadin antibody testing.
About this test
Deamidation changes gliadin, a protein found in wheat, in a way that makes it bind more strongly to antibodies associated with celiac disease. This assay looks for IgA antibodies against those deamidated peptides in a serum sample, using an immunoassay method.
Gliadin antibodies of the standard, non-deamidated kind can appear in people who do not have celiac disease, which limits how specific they are. Quest notes that this is also true to some degree of gliadin antibodies generally, and that the deamidated peptide version improves on the accuracy of standard gliadin antibody assays.
Who might consider this test?
- Because a single antibody result is read alongside other findings, it is often one piece of a larger evaluation rather than a standalone answer.
Test details
| Quest code | 11228 |
|---|---|
| Methodology | Immunoassay |
| Sample type | 1 mL serum |
| Collection | Quest patient service center |
Related tests and panels
Measures IgG and IgA antibodies to deamidated gliadin peptides, used in celiac…
Quest resources
Additional details
What this test looks at
The test reports one value: the level of IgA antibody to deamidated gliadin peptide in a 1 mL serum sample, run by immunoassay. Quest also lists this test under names related to celiac and gluten intolerance.
How it's often used alongside other tests
Quest describes gliadin antibodies as less specific than endomysial or transglutaminase antibody assays, since they can occur in people without celiac disease. The deamidated peptide version is described as more accurate than standard gliadin antibody testing, which is why a clinician may read it together with other celiac-related antibody tests rather than on its own.
Order online and a physician order is included — no doctor's visit and no insurance needed. Your sample is collected at a Quest Diagnostics patient service center.
Laboratory results should always be interpreted by a licensed clinician who knows your health history. This page is information about a test, not medical advice.
Frequently asked questions
What does the Gliadin (Deamidated) Antibody (IgA) test measure?
It measures IgA antibodies that bind deamidated gliadin peptides in a serum sample, using an immunoassay method. It is used in evaluating celiac disease.
How is the sample collected?
The test uses a 1 mL serum sample from a routine blood draw at a Quest Diagnostics patient service center.
Do I need to prepare for this test?
No preparation instructions are listed for this test, though people follow any instructions their ordering clinician provides.
Is this the same as a standard gliadin antibody test?
No. Both look for antibodies to gliadin, but this assay targets the deamidated form of the peptide, which Quest describes as having higher diagnostic accuracy than standard gliadin antibody testing.
Can this test result alone confirm celiac disease?
Gliadin antibodies, including the deamidated form, are described by Quest as less specific than endomysial or transglutaminase antibody assays, so results are read by a clinician alongside other findings.
How much is a Gliadin IgA test?
$85, paid once at checkout. The price includes the physician's order this test requires and sample collection at a Quest patient service center.