Test Details
Methodology
Enzyme immunoassay (EIA)
Result Turnaround Time
2 - 3 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
Detection of antibodies to aid in the diagnosis of gluten-sensitive enteropathy (GSE), such as celiac disease and dermatitis herpetiformis
Limitations
A negative tTG IgA result in an untreated patient does not rule out gluten-sensitive enteropathy. This result can often be explained by selective IgA deficiency, a relatively frequent finding in celiac disease. Results of this assay should be used in conjunction with clinical findings and other serological tests.
Footnotes
Custom Additional Information
Studies have demonstrated that IgA endomysial antibody tests have >99% specificity for gluten-sensitive enteropathy.1 Recently, the endomysial antigen has been identified as the protein cross-linking enzyme known as tissue transglutaminase (tTG).2
Specimen Requirements
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL (Note: This volume does not allow for repeat testing.)
Container
Red-top tube or gel-barrier tube
Collection Instructions
Specimen should be free of bacterial contamination, hemolysis, and lipemia.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 14 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Reference Range
• Negative: 0−3 units/mL
• Weak positive: 4−10 units/mL
• Positive: >10 units/mL
Storage Instructions
Room temperature
Causes for Rejection
Hemolysis; lipemia; gross bacterial contamination
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 164640 | t-Transglutaminase (tTG) IgA | 31017-7 | 164643 | t-Transglutaminase (tTG) IgA | U/mL | 31017-7 |
| Order Code | 164640 | |||||
| Order Code Name | t-Transglutaminase (tTG) IgA | |||||
| Order Loinc | 31017-7 | |||||
| Result Code | 164643 | |||||
| Result Code Name | t-Transglutaminase (tTG) IgA | |||||
| UofM | U/mL | |||||
| Result LOINC | 31017-7 |