Featured Tests

We are proud to assist in facilitating the diagnosis and management of celiac disease and other gluten-related disorders through the use of serological tests and HLA Typing.
 

Filling Test Tubes

Here is an introduction to celiac disease serology that can initiate diagnosis; HLA typing that can be used to exclude celiac disease; and the vitamin and mineral laboratory tests necessary to ensure that your patients are healthy. It is important to note that some of these tests can also be used to rule out celiac disease and even diagnose other gluten-related disorders through this exclusionary process. If you are looking for a more thorough explanation of these tests and the diagnosis process please head to It starts with a blood test. 

 
Celiac Disease Serology 
 
Blood tests are the first step in diagnosing celiac disease and can help determine the need for further evaluation for confirmation of celiac disease. It is important that patients continue to consume gluten as normal and do not start a gluten-free diet, as this can result in false negative test results. 
 
Although high titers in serological testing are indicative of celiac disease, they alone do not provide a definitive diagnosis of celiac disease and a biopsy of the small intestine is required for a definitive diagnosis1. Similar to serological testing, a normal, gluten-containing diet must also be maintained in order for the histological testing to be accurate.
 
There are several serological tests that are sensitive in the evaluation of celiac disease. These include antibodies to:
  • Endomysium
  • Transglutaminase
  • Deamidated gliadin 
Tissue transglutaminase antibody (tTG)-IgA in adults and most children is reported with a sensitivity and specificity greater than 90% and 95%, respectively2-4. Endomysial antibody (EMA)-IgA usually correlates with tTG. It is more costly and is identified manually, thus it is not the first line marker4.
 
 
What does our panel include?
 
Tests available include Tissue Transglutaminase Antibody (IgA) (test code 8821) and Endomysial Antibody Screen (IgA) with Reflex to Titer (test code 15064).
 
Physicians and hospitals can initiate testing for celiac disease by assessing the following antibodies. Celiac disease serology will normalize if the patient is on a gluten-free diet. Therefore, confirm that the patient is maintaining a normal, gluten-containing diet in order to ensure for the most accurate test results.
 
  • Total Immunoglobulin A Antibody (test code 539)
  • IgA-tTG (test code 8821)
  • If the IgA-tTG  is positive, IgA-EMA with Reflex to IgA-EMA Titer (test code 15064) will be performed.
  • If total IgA concentration is low IgG-tTG antibody test (test code 11070) will be performed.
  • Deamidated Gliadin Peptide Antibody (IgA (test code 11228/IgG (test code 11212) can be ordered for IgA deficient patients as well . 

What is the next step if serology is positive?
 
An esophagogastroduodenoscopy (EGD) and biopsy should be performed on the small intestine with 4-6 samples, one including the duodenal bulb1. Primary care providers and other non-gastroenterology specialists should refer patients to a gastroenterologist in order to confirm celiac disease. Remember, a normal, gluten-containing diet must also be maintained in order for the histological testing to be accurate.
 
 
What is the Function of Genetic Testing?
 
Complex genetics contribute to pathology as typical dominant or recessive traits are not followed16. The most contributory genetic material is the HLA class II: HLA-DQ2 (DQA1*05/DQB1*02), which is the most common, and/or HLA-DQ8 (DQA1*03/DQB1*0302) genes17.  One or both of these are present in celiac disease, accounting for up to 40% of the genetic load17. Different alpha and beta variants exist and can determine disease risk. We identify these to allow for individual patient interpretation. Examples of high risk variants include HLA-DQA1*03, HLA-DQA1*05, HLA-DQB1*0201 and HLA-DQB1*0302. A high negative predictive value is appreciated so if these genes are absent it is very unlikely that celiac disease can manifest18. Though the genes are common, presenting in approximately 30% to 40% of the general population in Americans and Europeans, only 1% to 3%-4% respectively develop celiac disease18. Family members of persons with celiac disease who have positive genetic testing are at an increased risk for developing celiac disease and should have their serology tested for celiac disease. While a consensus on the timeline of serology testing of family members of persons with diagnosed celiac disease does not exist at this time, clinical practices generally recommend follow-up testing every 1 to 3 years.

 
In what cases should you consider genetic testing?
 
Genetic testing is first and foremost a tool to rule out the risk for developing celiac disease. It is the only celiac disease test that does not have to be performed on a normal, gluten-containing diet. Genetic testing is particularly useful in infants and children with familial history or suspected celiac disease16. Genetic testing when negative in these young patients can spare the concern for disease surveillance for life. When accounting for other factors it is considered useful to aid in diagnosis. Some scenarios include young children who don’t produce adequate tTG or EMA antibodies, those on immunosuppressant drugs and those with other potential conditions causing the same histological changes in the small intestine as those of celiac disease1, such as giardia, milk allergy and other autoimmune diseases like Crohn’s.
Most especially, genetic testing can provide guidance with a particular dilemma that seems to be currently widespread – self-diagnosis of a gluten-related disorder. In those patients without a formal diagnosis, having self initiated the gluten-free diet for several months, having negative antibodies and/or biopsy and who will not undergo gluten challenge genetic testing can provide a scientific approach to an obscure scenario16.
We offer HLA typing for celiac disease. More information can be found here.
 
Once diagnosed, what are some other parameters you should check at baseline and during the management of celiac disease?
 
The National Institutes of Health (NIH) Consensus Statement on Celiac Disease recommends the following five key elements to celiac disease management19:
 
  • Consultation with a skilled dietitian
  • Education about the disease
  • Lifelong adherence to a gluten-free diet
  • Identification and treatment of nutritional deficiencies
  • Access to an advocacy group
  • Continuous long-term follow-up by a multidisciplinary team
We provide you with the following information and resources as your partner in helping you to facilitate and fulfill these five important elements. Additional information can be found at Helping Your Patients
 
 
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. [Epub ahead of print]
 
2. Leffler, D.A. & Schuppan, D. (2010). Update on serologic testing in celiac disease. Am J Gastroenterol. 105(12):2520-4.
 
3. Volta U, Fabbri A, Parisi C, et al. Old and new serological tests for celiac disease
screening. Expert Rev Gastroenterol Hepatol. 2010;4(1):31-35.
 
4. Leffler, D.A. (2011). Celiac disease diagnosis and management: A 46-year-old woman with anemia. JAMA, 306(14), 1582-1592.
 
5. Burgin-Wolff A, Dahlbom I, Hadziselimovic F, et al. Antibodies against human tissue transglutaminase and endomysium in diagnosing and monitoring coeliac disease. Scand J Gastroenterol 2002;37:685-91.
 
6. Vitoria JC, Arrieta A, Arranz C, et al. Antibodies to gliadin, endomysium, and tissue transglutaminase for the diagnosis of celiac disease. J Pediatr Gastroenterol Nutr 1999;29:571-4.
 
7. Holding S, Abuzakouk M, Dore PC. Antigliadin antibody testing for coeliac disease in children under 3 years of age is unhelpful. J Clin Pathol 2009;62:766-7.
 
8. Rostom, A., Murray, J.A., & Kagnoff, M.F. (2006). American Gastroenterological Association (AGA) Institute technical review on the diagnosis and management of celiac disease. Gastroenterology, 131:1981-2002.
 
9. Prince, H.E. (2006). Evaluation of the INOVA diagnostics enzyme-linked immunosorbent assay kits for measuring serum immunoglobulin G (IgG) and IgA to deamidated gliadin peptides. Clin Vaccine Immunol, 13, 150-151.
 
10. Kumar, V., Jarzabek-Chorzelska, M., Sulej, J., Karnewska, K., Farrell, T., & Jablonska, S. (2002). How Celiac Disease and Immunoglobulin A Deficiency: How Effective Are the Serological Methods of Diagnosis? Clinical and Vaccine Immunology, 9(6), 1295-1300. 
  
11. Hill ID, Dirks MH, Liptak GS, et al. Guideline for the diagnosis and treatment of celiac disease in children: recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition. 
J Pediatr Gastroenterol Nutr. 2005;40:1-19.
 
12. 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.
 
13.Corazza, G, Villanacci, V. Coeliac disease. Journal of Clinical Pathology. 2005;58:573-574.
 
14. Celiac Disease Toolkit. American Dietetic Association. 2011. www.eatright.org
(Name change January 1, 2012: Academy of Nutrition and Dietetics)
 
15. Leffler, D.A. (2010). Managing celiac disease: Following Patients with celiac disease. ACCME Accredited Continuing Medical Education Activity, www.CeliacCMECentral.com
 
16. Leffler, D., Dennis, M. Real Life with Celiac Disease. AGA. Bethesda, MD. 2010.
 
17. Liu, E., Rewers, M., Eisenbarth G. Genetic tesing: who should do the testing and what is the role of genetic testing in the setting of celiac disease? Gastroenterol. 2005; 128:33-37.
 
18. Frangou, C. Environmental factors examined in celiac disease. Gastroenterol Endoscopy News. 2011; 62:11.
 
19. NIH Consensus Development Conference on Celiac Disease, 2004.