Testing is the key to getting a definitive answer.
I’ll never forget when my daughter was officially diagnosed with celiac disease. The entire journey, from the onset of symptoms to the final confirmation from Emma’s gastroenterologist, is seared into my mind. Fifteen years ago I didn’t even know how to spell “celiac.”
The day you hear your child’s doctor say the words “celiac disease,” “tests” and “endoscopy” can be daunting as you face the prospect of dealing with a lifelong, chronic condition.
And then there’s the restrictive and unfamiliar diet that’s the only treatment. Even as it begins to sink in, your head is likely to be spinning with questions. What is involved in celiac disease testing? Does my child really need to go through all this? What are the long-term prospects for a normal, healthy life?
Testing is the place to start.
Emma started getting sick in 2000, around her first birthday. For months she had a cold she couldn’t shake. She had diarrhea and was vomiting and losing weight. At the same time, her belly was distended.
Despite the fact that Emma had classic gastrointestinal symptoms of celiac disease, it took four months and three doctors to get a final diagnosis.
Alessio Fasano, M.D., chief of the division of pediatric gastroenterology and nutrition at MassGeneral Hospital for Children in Boston and director of the Center for Celiac Research and Treatment there, says it is sometimes still hard to get a diagnosis of celiac disease because the common symptoms are just that…common.
“These are symptoms that every child at some point in his or her first years of life will experience,” Fasano says.
That might explain why our first doctor responded to my concerns about Emma’s bouts with vomiting by saying, “You know kids throw up, right?”
Extra-intestinal symptoms such as anemia, short stature and discoloration of teeth can also indicate celiac disease. Fasano says whether a child is suffering from classic gastrointestinal or extra-intestinal symptoms, when they are prolonged and start to affect the child’s lifestyle, doctors should begin looking for answers.
How celiac disease is diagnosed
Diagnosis of celiac disease begins with a blood test, which you might also hear called serology. The simple test can be done at your pediatrician’s office, and you get the results in a few days. The test looks for specific biomarkers, known as anti-tissue transglutaminase (tTG) antibodies, indicative of celiac disease.
Tasha Miller of Naperville, Illinois, was shocked when her then 14-year-old son Ryan’s bloodwork came back positive for celiac disease. He was tested along with his older and younger brothers in 2014 because Miller’s husband was concerned their youngest son, Adam, had symptoms that might be celiac disease. But Adam’s test came back negative, and Ryan was the only one who had positive results.
Ryan then went through the traditional second step. He had an endoscopy to confirm his diagnosis. During an endoscopy the child is put under anesthesia, and doctors insert a tube through the mouth and into the small intestine to biopsy a few samples of the intestinal lining. After the procedure, doctors might have some idea how likely celiac disease is based on what they’ve observed, but they cannot confirm the diagnosis until the biopsy sample is analyzed by a pathologist. That procedure usually takes a few days.
Some gastroenterologists wonder whether children still need to undergo the endoscopy to confirm celiac disease. Fasano says the European Society for Pediatric Gastroenterology, Hepatology and Nutrition supports the idea that if a child has symptoms, a positive blood test, carries the HLA DQ2 and/or DQ8 gene found in people with celiac disease and has resolution of symptoms on the gluten-free diet, the endoscopy is unnecessary.
But Fasano always recommends the endoscopy to confirm the final diagnosis. “The information you gain from this really overcomes the possible risk of putting your kids through a procedure like an endoscopy,” he notes.
When Ryan had his endoscopy, Miller says doctors explained what they were going to do before the procedure started. “He came out of the procedure slowly but fine,” Miller recalls. “It took him about an hour or so to wake up and readjust to the world.” Since the throat can be a bit tender after having the tube inserted, Miller says Ryan had a gluten-free milkshake on the way home.
Unlike Emma, Ryan had no symptoms of celiac disease. But his mother says it was good fortune that he was diagnosed. “I am glad we discovered it,” Miller says, adding that Ryan took charge of his gluten-free diet and does not cheat. And he has grown several inches since his diagnosis.
Fasano is often asked whether an asymptomatic child really needs to go gluten free. He says asymptomatic children who have been diagnosed should go on the gluten-free diet to help prevent future, and potentially worse, symptoms, such as diabetes. “Then it is too late, there is nothing you can do about it,” Fasano says. Additionally lack of symptoms does not mean that damage is not being done to the absorbing lining of the intestine.
Young children are more likely to have classic gastrointestinal symptoms, making them easier to diagnose than teenagers, Fasano says. Teens’ symptoms tend to be more random. And they are more independent and more focused on their friends and fitting in. As a result they might not share information with their parents.
“In general parents’ IQs drop 100 points when a kid goes from childhood to being a teenager,” Fasano says. “Therefore they are not seeking their parents’ advice with the symptoms they may be experiencing.”
What parents need to know
If your child is having symptoms of celiac disease or you have a family history of the condition, Fasano says these are the things you need to know:
Get the blood test. It is simple, cheap and reliable.
Do not put your child on a gluten-free diet to see if he or she feels better before getting tested.
“Among all the mistakes that can be made, [taking your child off gluten before testing] is the most severe one you can imagine,” Fasano says. Test results may not be accurate if the gluten-free diet is being followed, and you will not be able to get a definitive diagnosis. “You would not do this with any other disease,” Fasano says. “Nobody would dare put their child on insulin just because he or she is urinating or drinking too much [even though these are common signs of diabetes].”
Follow the blood testing with an endoscopy and biopsy of the small intestine.
“In lieu of more solid data, I would suggest the endoscopy is still needed to confirm a celiac diagnosis,” Fasano says. “I am not disputing the fact that in the future we may get rid of the endoscopy, but I don’t think we are there yet.”
If your child does have celiac disease, other family members should also be tested because it is a genetic autoimmune disease.
You should also consider genetic testing for the family. This test, which is also done by collecting a blood sample, determines if you carry the genes necessary to have celiac disease. If someone has a negative test result, it rules out the possibility that celiac disease will develop and makes repeated antibody tests unnecessary. If the test is positive, it does not mean you or your child have celiac disease, only the potential to develop it, in which case antibody tests should be done periodically.
Armed with this information, you can prepare yourself and your child for testing for celiac disease, with the goal of getting the most accurate result possible.
Blood tests for celiac disease
- Anti-tissue transglutaminase antibody (tTG-IgA): This is the primary blood test used to diagnose celiac disease. It looks for the two types of antibodies found in the blood when someone has celiac disease: immunoglobulin A (IgA) and immunoglobulin G (IgG). The test is also used as a follow up to see how well a celiac disease patient is doing on a gluten-free diet. If gluten is getting into the diet, antibodies will show up.
- Total serum IgA: This tests for IgA deficiency, a condition that can cause a false IgA-anti-tTG or EMA result. This test is often done in conjunction with the tTg-IgA.
- Deamidated gliadin peptide (DGP IgA and IgG): This is a go-to test if the IgA levels are low and the anti-tTg test is negative. It is also a good test for celiac disease in children younger than 2 years old because their levels of IgA-anti-tTG can fluctuate at this age, Fasano says.
- IgA endomysial antibody (EMA): While very accurate, this test is not as sensitive as the IgA-anti-tTg. EMA is done by an indirect immunofluorescent assay, a more expensive and time-consuming process than the anti-tTG’s ELISA testing. It is often reserved for patients who are more difficult to diagnose.
Sources: Alessio Fasano, M.D. director of MassGeneral Hospital for Children’s Center for Celiac Research and Treatment, Celiac.org, LabTestsOnline.org and NIDDK.NIH.gov
Amy Leger is the family editor for Gluten-Free Living. She lives in Minnesota with her husband and two daughters, one of whom has celiac disease. She also blogs about the gluten-free lifestyle on her website, thesavvyceliac.com.