How well do gluten-free diets eliminate gluten, and is home gluten testing a good thing?

gluten testing could help predict intestinal health in patients with celiac disease

For patients with celiac disease, following a gluten-free diet is complicated and often challenging.

“Our patients are navigating a gluten-free diet without any feedback to guide them,” says Jocelyn Silvester, MD, PhD, director of research at the Celiac Disease Program at Boston Children’s Hospital. “Symptoms are not a reliable indicator of gluten exposure. Many patients may not have any symptoms at all.”

For clinicians, assessing how well patients are doing on a gluten-free diet can be equally difficult. “There are no good measures of how well the gluten-free-diet is working or how well patients are following the diet,” Silvester says.

Moreover, tolerance to gluten can vary in celiac disease. Some children have symptoms despite being (apparently) on a gluten-free diet. Others have no symptoms after a gluten exposure, yet show severe atrophy of the nutrient-absorbing villi on intestinal biopsy. Villous atrophy poses a risk for complications, such as poor growth, anemia and osteoporosis.

Recently developed tests can detect gluten peptides in stool and urine, reflecting how much gluten is being consumed. Silvester is now leading a pair of studies utilizing these tests in children with celiac disease.

“These tools have the potential to revolutionize how a gluten-free diet is managed, similar to how patient testing of blood sugar has improved care for children with type 1 diabetes on insulin,” Silvester says. “But we need to figure out the best way to use them to help patients.”

How much gluten are children getting?

Both studies will use tests from a company called Glutenostics LLC. The tests can detect trace concentrations of gluten, and some tests can be done by patients at home.

The first study, to involve 200 children, will apply the tests to urine and stool samples provided by patients in the clinic. The test results will then be compared with blood measures of celiac disease activity and gluten-free diet adherence, such as antibodies and nutritional biomarkers.

The findings will help determine just how much of a problem gluten “contamination” is in a gluten-free diet. Silvester also hopes the tests will offer a better, non-invasive way to predict intestinal mucosal damage. She and her colleagues recently conducted a meta-analysis of existing antibody tests. The tests had poor sensitivity (below 50 percent) for detecting persistent villous atrophy in patients with biopsy-confirmed celiac disease who were trying to follow gluten-free diets.

Home gluten testing?

The second clinical trial is recruiting children age 6 and up and asking, “How does putting testing in parents’ hands affect them?”

Half the families will receive Gluten Detective, a home test that lets them monitor stool and urine gluten themselves. Over a period of 25 weeks, families will test their children’s urine and stool six times. A control group of families will simply collect and store the samples and bring them to a clinic visit.

Aside from seeing how well gluten-free diets actually eliminate gluten, Silvester and her colleagues hope to get a handle on whether home testing will help patients reduce gluten intake over time.

“We’re asking, ‘what is the impact of using this tool?’” Silvester says. “A lot of people are very anxious about gluten. Are we making their anxiety worse? Or does knowing how much gluten they’re getting reassure kids and their families and empower them to better avoid gluten in the future?”

For further information on enrolling in these studies, email celiacresearch@childrens.harvard.edu.