One of the big misconceptions floating around about celiac disease is how to get tested and when to stop eating gluten. Because of ongoing frustrations with convincing some physicians to order a celiac disease blood test or possibly all of the media attention on how a gluten-free diet can change your life, many people are taking it upon themselves to test out a gluten-free diet to see if they feel better after a few weeks. In many cases, the diet works out perfectly and the patients begin feeling relief of the symptoms.
At this point, the patient goes to the doctor to tell them about their success and asks for the celiac test. The problem begins here if the doctor immediately runs the test. In order to receive an accurate celiac disease blood test or endoscopy (small bowel biopsy), a patient must be eating gluten for a considerable about of time to build up the antibodies that are measured on the test. If the patient is not eating gluten, the test will come back negative even if the person has celiac disease. Thus it is incredibly important to be on a full gluten-containing diet before the test.
How much gluten should you eat? Medical professionals disagree on the exact amount, but the Canadian Celiac Association suggests the equivalent of 1 to 4 slices of bread daily for 4 weeks.
So what are the various tests for celiac disease?
Antibody Celiac Test
An antibody celiac test is measuring anti-endomysium and anti-tissue transglutaminase. The antibody test will determine the response a patient's body is having to the gluten protein. A person with Celiac Disease will have higher-than-normal antibody levels.
antibody test is made up of a panel consisting of Anti-Tissue
Transglutaminase (tTG-IgA), Total Serum IgA and anti-endomysial
antibody (EMA-IgA). In order for the test to be accurate, patients must
be eating gluten regularly. This is equivalent to about four servings
per day for six weeks. If a patient has a positive antibody test, they
will need a small intestine biopsy to confirm a celiac diagnosis.
The genetic test for Celiac Disease is used for two reasons. The first is to rule out a celiac disease diagnosis if the HLA-DQ2 and HLA-DQ8 genes are not present. If a patient does not have these genes, it is nearly impossible for them to develop Celiac Disease. In this case, they would not need a follow-up antibody test or small intestine biopsy
The second reason for the genetic test is to determine a possible diagnosis in patients that are already living on a gluten-free diet. Having the HLA-DQ2 and HLA-DQ8 genes does not definitely mean a person has celiac disease, however it does put them in a high-risk group that requires further testing.
Small Intestine Biopsy
If a patient receives a positive antibody or genetic test, it is strongly recommended that he or she undergo a small bowel biopsy to determine if there is damage to the villi. The biopsy is taken using an endoscope, which is a long, thin tube that the physician weaves through the mouth and stomach to reach the small intestine. The biopsy is the gold standard of diagnosis and the only definite way to determine an accurate celiac diagnosis.
Home Celiac Test Kit
The Biocard Celiac Test Kit is an at-home test that measures (anti-tTG) IgA antibodies from a fingertip blood sample. It works by taking a small blood sample from pricking your finger, mixing the blood with a buffer and applying the mixture onto a test cartridge. The test can be administered from the comfort of your own home and you’ll get results in just 10 minutes. The Biocard Celiac Test is positive if you have two red lines on the test cartridge. One red line appears in the control field, which indicates that you have done the test correctly. The second red line will only appear if you are having an immune system response to the gluten protein. If the test comes out positive for celiac disease, the makers of the test recommend consulting with a doctor to confirm the diagnosis with an intestinal biopsy.