Test Description

In celiac disease, the body produces two types of antibodies that attack the intestinal wall: tissue transglutaminase (anti-tTG) immunoglobulin A (IgA) and immunoglobulin G (IgG). Measuring the IgA form of tTG antibody in the blood is more useful in detecting celiac disease because it’ is made in the small intestine, where gluten causes inflammation and irritation in gluten-sensitive people.

When should this test be ordered?
The anti-tTG IgA test is the preferred test for celiac disease if the patient has normal or elevated IgA levels. It is ordered along with DGP IgA as a confirmation test before proceeding to biopsy which if positive leads to “Presumptive Celiac Disease Diagnosis”.
High Risk · >= 1.06 ( ratio, no units)
Suggestive of celiac disease as per AGA guidelines. Subsequent genetic testing for HLA-DQ association may be indicated for further patient evaluation.
Borderline Risk · 0.95-1.05 ( ratio, no units)
Suggestive of celiac disease as per AGA guidelines. Subsequent genetic testing for HLA-DQ association may be indicated for further patient evaluation.
Low Risk · <= 0.94 ( ratio, no units)
A low titer for tTG IgA and DGP IgA means the patient most likely does not have celiac disease. It is recommended that the patient go on a gluten free diet to see if symptoms improve as the patient might have non-celiac gluten sensitivity.
Testing Method Used
Immunofluorescence assay.

Sample is stable for 5 days at 2-8°C.

Please ship samples daily.
Improvements and Prevention
To ease symptoms of celiac disease, eliminate all products containing gluten. Check all food labels very carefully for wheat products. Use a diet high in fruits, vegetables, lean meats, beans, rice and legumes and avoid baked goods made with any type of flour, foods fried in batter, and processed cereals
Specimen Type
Serum
Fasting Required
No, but may be done with other tests that requires fasting.
Drawing and Processing
  1. Draw from a vein into a SST tubetube1
  2. Invert tube (do not shake) 1-2 times to mix adequately
  3. Let stand upright in tube rack for 30 minutes
  4. Centrifuge for 15 minutes at 3300rpm
  5. Do not leave at room temperature for more than 1 hour
  6. Keep cold in a refrigerator to maintain stability, until ready to ship
Shipping Instructions
  1. Freeze ice packs 24 hours prior to use
  2. Place ice packs inside the Styrofoam insulated kit
  3. Place processed tubes inside biohazard bag, place inside kit
  4. Seal box, print airbill and adhere to box and wait for courier to pick up
Rejection Criteria
QNS; temperature out of range upon receipt; grossly lipemic or hemolyzed; wrong specimen type; sample stability exceeded for this analyte; unlabeled or mislabeled specimen.
References

1. Ludvigsson JF, Leffler DA, Bai JC, Biagi F, Fasano A, Green PH, Hadjivassiliou M, Kaukinen K, Kelly CP, Leonard JN, Lundin KE, Murray JA, Sanders DS, Walker MM, Zingone F, Ciacci C. (2012). The Oslo definitions for coeliac disease and related terms. Gut, Feb 16.

2. Oberhuber, G, Granditsch, G, Vogelsang, H. The histopathology of coeliac disease: time for a standardized report scheme for pathologist. European J Gastroenterol. & Hepatology. 1999; 11:1185-1194.

3. NIH Consensus Development Conference on Celiac Disease, 2004.

The information provided here is intended for educational purposes only and should not be used or substituted as medical advice. You should consult a healthcare practitioner regarding medical diagnosis or treatment.

* Vibrant™ Tests have been developed and its performance characteristics determined by the CLIA-certified laboratory performing the test. This test has not been cleared or approved by the U.S. Food and Drug Administration (FDA). Although FDA does not currently clear or approve laboratory-developed tests in the U.S., certification of the laboratory is required under CLIA to ensure the quality and validity of the tests.