Celiac Disease Gluten-Free Cascade, Serum and Whole Blood
Use
Evaluating patients suspected of having celiac disease who are currently (or were recently) on a gluten-free diet. This cascade should not be used in patients for whom HLA DQ2/DQ8 typing has already been performed. It is suitable for patients who are on a gluten-free diet, as traditional serologic tests may yield false-negative results in these individuals. Cascade testing ensures that testing proceeds in an algorithmic fashion, minimizing unnecessary tests and costs.
Special Instructions
If HLA-DQ typing is positive or equivocal for DQ2 or DQ8, then additional antibody testing will be performed at an additional charge. This test should not be solely relied upon to establish a diagnosis of celiac disease; it is used to identify patients with increased probability of the disease. Ordering the Gastroenterology and Hepatology Test Request form is necessary if not ordering electronically.
Limitations
Genetic markers HLA-DQ2 and HLA-DQ8 are required but not sufficient for the development of celiac disease; not all individuals with these alleles will develop celiac disease. A small intestinal biopsy remains the gold standard for diagnosis. IgA deficiency must be considered as it may require additional IgG antibody testing. Results must be interpreted in the context of clinical symptoms and serological findings.
New York Approved
Methodology
PCR-based
Biomarkers
LOINC Codes
- 94493-4
- 94495-9
- 53938-7
- 48767-8
- 69048-7
Result Turnaround Time
9-11 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
6 mL
Minimum Volume
3 mL
Container
Yellow top (ACD solution A or B)
Collection Instructions
Send whole blood in original tube. Do not aliquot.
Causes for Rejection
Gross hemolysis, Gross lipemia
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 21 days |
| Frozen | 21 days |