Frequently Asked Questions
1. What are the benefits of the Celiac Screening?
Semi-quantitative analysis of anti-gliadin antibodies and anti-tissue transglutaminase (tTG) antibody through ELISA procedure.
Only a few drops of blood required
Analysis completed in the U.S.
Comprehensive supporting information in client information sheets
2. Why shall I choose blood test for Celiac Disease?
Blood test is a very convenient way and much less invasive method, compared to upper endoscopy and intestinal biopsy. Using blood test can reduce the discomfort and lesions caused by these invasive methods. IgA-tTG, IgG-Gliadin and IgA-Gliadin tests constitute valuable diagnostic tools in the decision for more invasive intestinal biopsy. Also, they have been proven their values for the follow-up of CD and have revelaed the high prevalence of undiagnosed CD. Therefore, a scientific journal suggested that rather than ordering a redundant panel, it is far better to start with IgA-tTG and follow up as necessary.
3. How do I go about the Celiac Screening?
There are two ways for completing the test.
First, you can make an appointment to complete the blood collection process in our office.
You can purchase the test kit from us, collect the blood sample at home, and return it back to our office.
|Mon. - Fri.
||10am - 7pm
||9am - 5pm
|Sun. & Public Holidays Closed
We will send your sample direct to the US lab for testing. You will receive the results within within 10 - 20 days.
4. How much blood is needed for the Celiac Screening?
Only a few drops of blood are required.
5. How can you ensure the blood collected in the strips will not be contaminated during transit?
First of all, dry blood provides no medium for bacteria to attack. Therefore, it is essential that you follow the instruction and allow the blood to dry for at least 45 minutes in room temperature. In addition, our blood collection strips use a proprietary collection methodology that's proven to provide stable test results for the blood sample for at least 3 weeks. Our comparison study between blood sample collected on the strips and those stored in serum showed no discrepancy in results. So, the strips are as effective as blood collection serums.
6. Could we know more about the specificity and accuracy of the Celiac Screening?
Our Celiac Screening utilizes the state of the art ELISA Procedures and it is a stringent biochemical process whereby the antibodies are detected in your blood, and it is a direct measurement of your immune system's response to food. The Celiac Screening gives you the assurance of quality and reliability as all tests are completed by our Laboratories in the United States, and each patient's test is conducted twice to ensure accuracy and reliability. Our laboratory is an independent clinical laboratory approved by CLIA (US Clinical Laboratory Improvement Amendments) accredited by COLA (US Commission on Office Laboratory Accredition). The laboratory is also licensed by the State of Washington for performing testing worldwide.
7. Is Celiac Screening a diagnosis?
Celiac Screening consists of anti-gliadin antibodies and anti-tisue transglutaminase antibody screening, which in combination are considered to be a very reliable primary screening tool for Celiac Disease, even though it cannot replace any diagnosis made by medical doctor.
8. Why does the Celiac Screening test ‘IgA against tTG’ (tissue transglutaminase)?
In celiac disease, the body produces antibodies that attack tTG. IgA antibody is made in the small intestine where gliadin causes inflammation irritation in sensitive people. By measuring the IgA antibodies in blood, we investigate our body’s response to gliadin which is useful in detecting celiac disease.
9. Why does the Celiac Screening test IgA and IgG against gliadin?
It is expected a celiac sufferer makes antibodies against gliadin, the protein which is responsible for celiac disease and which the body recognizes as an antigen. IgA antibodies are normally measured since this is the major immunoglobulin involved in the gut immune response. In those people who are IgA deficient from birth, which we know is more common in celiac disease, IgG antibody produced by the body can be tested instead. Also, IgG represents a longer term immune response.
10. Why does my doctor order additional test?
Nowadays, blood test for CD relies heavily on IgA levels in individuals. However, there is one IgA-deficient CD patient in every forty CD patients while one in every four hundred normal people. For these IgA-deficient individuals, an additional test, which total IgA test, for IgA deficiency verification shall be used and analytes other than IgA shall be used, such as IgG against gliadin.
11. Is the Celiac Screening suitable for all ages?
Adults and children can take the test. In general, infants after 6 months start weaning and eating solid foods, probably containing gluten. Thus, kids age after 6 months and starting eating solid gluten-containing foods can take the test.
12. Do I need a doctor’s prescription to have the Celiac Screening done?
In general, any individual can order any tests for themselves. A doctor’s prescription is not required.
13. Can I have this test done if I am taking Chinese or Western medicine?
You may please consult your practitioner if you have any questions concerning your Chinese medicine. In general, the major concern is steroidal drugs, e.g. cortisone, because it can suppress the immune system, and thus may reduce the antibodies present, causing a "false negative" report. Thus it is advisable to stop taking the steroidal drug for at least 3 weeks before taking the test. Tropical steroid is not part of the concerns.
14. What information will the Celiac Screening report provide?
Celiac Screening result would be shown as values of different analytes and reference value for each analyte is provided.
Elevated serology is recognized in untreated celiac disease patients. Repeat testing may be used to assess response to treatment. Persistently elevated antibody levels may suggest lack of adherence to a gluten-free diet.
15. What do I have to be aware of after I get my test results?
IgA to tTG is recognized to be of over 90% accuracy and specificity internationally. But these parameters may be compromised in IgA-deficient individuals, individuals in mild disease or with karyotype abnormalities or with diabetes and children under three years of age. If anyone with a negative test result and symptoms suggestive of CD, they should visit physicians and consider an upper endoscopy and intestinal biopsy.
16. What if I have been following a gluten-free diet?
For all diagnostic tests for CD test to work properly, one must eat gluten daily. If you have avoided gluten for a long period of time, there may be false negative results in all diagnostic methods for CD. Some physicians recommend patients be on a gluten-containing diet for 2-4 weeks before serologic testing.
17. Can I overgrow Celiac Disease?
There is no scientific evidence that anyone can outgrow CD once he/she is diagnosed with CD because it is a genetic disease. Hence, the genetically predisposed individuals will develop symptoms every time when they eat gluten-containing foods, even though there are asymptomatic CD patients, whereas all symptoms and damages of their bodies will be fully recovered when they avoid gluten for a certain period of time. Therefore, the CD patients are recommended to avoid gluten once they are diagnosed.
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