new to the gluten free journey?
Menu
new to the gluten free journey?
The first step along the journey to addressing symptoms and healing the body is a proper diagnosis. This article will discuss the process for getting a celiac disease test, including the different types of testing and the pros and cons of each.
Celiac disease is an autoimmune disorder characterized by a reaction to ingested gluten in genetically predisposed individuals. The immune response to gluten damages the villi of the small intestine, leading to malabsorption of nutrients and a number of other health complications.
Celiac disease is sometimes confused with a wheat allergy or non celiac gluten sensitivity, but these are different conditions.
A wheat allergy causes an immune response in the body when wheat is either ingested (food allergy) or inhaled (respiratory allergy).
An allergic reaction to wheat can manifest with a variety of symptoms that include hives, skin swelling, asthma, allergic rhinitis, abdominal pain, vomiting, acute exacerbation of atopic dermatitis, and exercise-induced anaphylaxis.
Wheat allergy can be diagnosed with testing from your doctor. The tests include either skin prick or blood tests measuring IgE response to wheat.
Non Celiac Gluten Sensitivity (Gluten Sensitivity) is a condition where individuals experience symptoms similar to those of celiac disease after consuming gluten, but without evidence of villous atrophy occurring in the intestinal lining. The exact mechanism is not fully elucidated, but genetics, history of infection, using certain medications (antibiotics, steroids, NSAIDS, and ARB’s), altered gut microbiota and low-grade inflammation are all believed to play a role.
In both celiac disease and non celiac gluten sensitivity, gluten consumption triggers symptoms. The symptoms of gluten exposure can vary greatly from person to person which can make a diagnosis challenging. In addition, symptoms extend far beyond the digestive concerns that are most commonly discussed with respect to celiac disease,. Common symptoms include the following:
The process for getting a celiac disease test may vary slightly depending on your healthcare practitioner.
For many providers, blood tests are the first step in a diagnosis of celiac disease. These blood tests measure your body’s response to gluten. Before getting into the specifics of the tests, it is important to understand that a few things first.
Range of Sensitivity and Specificity and Use of Current Serologic Tests for Celiac Disease
Serologic Study | Sensitivity | Specificity | Application in Clinical Practice |
|---|---|---|---|
IgA tTg | 73.9% – 100% | 77.8% – 100% | First-line testing to screen for celiac disease |
IgG DGP | 80.1% – 96.9% | 86.0% – 96.9% | First-line testing for celiac disease in patients with IgA deficiency |
IgA EMA | 82.6% – 100% | 94.7% – 100% | Second-line confirmatory test to screen for celiac disease |
IgG tTG | 12.6% – 99.3% | 86.3% – 100% | Not recommended for routine use because of poor sensitivity compared with IgG DGP |
IgA DGP | 80.7% -95.1% | 86.3% – 93.1% | Not recommended for routine use because of poor sensitivity and specificity compared with IgA tTG and IgA EMA |
Leonard, M. M., Sapone, A., Catassi, C., & Fasano, A. (2017). Celiac Disease and Nonceliac Gluten Sensitivity: A Review. JAMA, 318(7), 647–656. https://doi.org/10.1001/jama.2017.9730
However, all of the above blood tests are not 100% reliable as they can easily present false negatives. IgA deficiency is 10-15 times more common in those with celiac disease, therefore contributing to the potential for false negative tTG, anti gliadin antibodies, and EMA IgA based tests.
If any of the blood test markers do come back high, some practitioners will have a patient try a gluten free diet, while others will move onto further testing with an endoscopy. We discuss the process for endoscopy below.
The process for testing may not be the same for everybody, but it is important to advocate for a comprehensive evaluation in order to get to the root of your symptoms. Don’t let one negative test derail your quest for answers and an accurate diagnosis.
There are several different options to test for celiac disease, described below.
As discussed above, a blood test checks for certain antibodies. People with celiac disease who eat gluten produce antibodies in their blood because their immune systems view gluten as a threat. It is important to note that you must be on a gluten-containing diet for antibody blood testing. It is also important to note that these types of tests can also be misleading, as they can come back falsely negative. There are several studies that highlight inaccurate results.
A food sensitivity blood test can also be helpful for identifying foods that trigger similar symptoms like bloating, diarrhea, abdominal discomfort, skin issues, brain fog, and more.
An endoscopy is when a tube is inserted down your throat so that a practitioner can look at your small intestine for inflammation or damage (villous atrophy). They may also take a small biopsy of your intestines. Like blood testing, you must be eating a diet that contains gluten for this test to be accurate. This type of testing is accurate when positive, but missed diagnosis is common. In fact, one study found that endoscopy had low sensitivity (below 50%) in detection of persistent villous atrophy. The authors called for “more-accurate non-invasive markers of mucosal damage in children and adults with celiac disease.”
A biopsy finding villous atrophy can also be misleading because other things can cause atrophy beyond gluten, such as parasites, glyphosate, non steroidal anti inflammatories (NSAIDS), proton pump inhibitors (PPIs) used traditionally for heartburn, selective serotonin reuptake inhibitors (SSRIs) used for depression and mood disorders, etc. If you are taking any of these medications, it is important to inform your doctor before scheduling a biopsy so as to avoid the possibility of a false positive test. A more comprehensive list of other causes and contributing factors to villous atrophy and intestinal inflammation can be found in the diagram below:
Medication Induced | Infections | Chemical Exposure | Malnutrition | Food Reaction |
|---|---|---|---|---|
Antibiotics | Parasitic | Glyphosate | Anorexia | Food Allergies |
NSAIDs | Bacterial | Mercury | B3 Deficiency | Food Sensitivities |
Proton Pump Inhibitors | Viral Infections | Cadmium | Vit. A Deficiency | Alcoholic Drinks |
SSRI’s | SIBO | Use of Nitrogen Fertilizers on Grains | L-Glutamine Deficiency | Artificial Sweeteners |
Chemotherapy | Candida Overgrowth | Persistent Organic Pollutants | Butyrate Deficiency | Emulsifiers |
Radiation | Mycotoxins | Protein Deficiency | Food Dyes | |
Corticosteroids | Iron Deficiency | Meat Glue | ||
Angiotensin Receptor Blockers | Folate Deficiency | |||
Biologics | B12 Deficiency |
The benefit of blood testing is that it is quick, non invasive, and if positive can help a person understand the need to go gluten free. The downside is that it can be misleading and show false negative results.
Although helpful in determining a celiac diagnosis, endoscopy testing can be misleading because there are other things that can cause villous atrophy beyond gluten.
The downside to both tests is that you must be eating gluten in order to get an accurate test result. Many people who suspect celiac disease have started eating gluten free and have started to feel better. Having to reintroduce gluten can cause a resurgence of symptoms and further deterioration of health.
Genetic testing is a highly accurate look at your genes to understand whether you have a genetic predisposition to reacting to gluten. You do not need to be eating gluten in order to get an accurate test result. Research indicates that clinical manifestations, like those found through blood testing and endoscopy, are not sufficient for a true diagnosis. A genetic test shows a more complete picture. Make sure to get a test that measures for all genes linked to gluten sensitivity (HLA-DQ1/HLA-DQ3) and celiac disease (HLA-DQ2/HLA-DQ8). Some tests only check for genes linked to celiac disease.
Put simply, a celiac disease diagnosis can change your life. This isn’t just because a celiac disease diagnosis involves some lifestyle changes, but because there are risks involved with undiagnosed celiac disease. Some of these risks include the following:
One of the most common misconceptions about celiac disease testing is that it is foolproof. As discussed above, celiac disease testing can result in false negatives. If you are having symptoms and/or have a family history of celiac disease and your test is negative, continue onto other testing methods.
Occasionally, people are concerned about discomforts associated with testing. The least invasive testing is genetic testing, which involves a simple swab of your cheek. Blood testing is also minimally invasive, but can be stressful for those who have a fear of blood or needles. Endoscopy is the most invasive testing method, however, you will be sedated and should not feel any discomfort during the procedure. Discuss any fears or concerns about testing with your practitioner.
Accurate testing and diagnosis for celiac disease is critical for your health in both the short and long term. Please feel empowered to seek the appropriate testing and practitioner support that you need and deserve.
Want to start simply? Take the Gluten Sensitivity Test.
Stay up-to-date with the latest articles, tips, recipes and more.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
If you are pregnant, nursing, taking medication, or have a medical condition, consult your physician before using this product.
The entire contents of this website are based upon the opinions of Peter Osborne, unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Peter Osborne and his community. Peter Osborne encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional.
© 2024 Gluten Free Society. All rights reserved.