In part three of our series on type 1 diabetes (T1D) and celiac disease (CD), we interviewed Dr. Edwin Liu, a pediatric gastroenterologist at Children’s Hospital Colorado and the director of the Colorado Center for Celiac Disease. We wanted to know how he screens people for CD, how CD changes diabetes management, and any advice he has for someone recently diagnosed with CD.
How do you determine if someone should be tested for Celiac Disease?
There are two ways to think about celiac disease screening: one is to test when someone has symptoms suggestive of celiac disease. The other is to screen someone because they have a known risk for celiac disease, such as a family history of celiac disease, type 1 diabetes, autoimmune thyroid disease or Down Syndrome to name a few. However, the problem with either approach is that targeted screening based purely on symptoms would miss about half of all cases, and testing based on genetic risk would also miss most cases since the majority of people with celiac disease actually don’t fall into a high-risk category. Therefore, the only effective way to truly find all cases would be to screen everyone, or first do genetic testing and then screen those with HLA-permissive genes.
What symptoms, if any, do you most commonly see before testing someone?
In the GI clinic, the most common symptom is probably abdominal pain, which can be very nonspecific. Therefore, having a high index of suspicion for celiac disease is important. However, nearly half of all patients that we see with celiac disease have been identified based on screening and have mostly subclinical features.
How do you test someone for Celiac Disease and do you feel the test is accurate enough?
The single best test for celiac disease is the tissue Transglutaminase autoantibody test in conjunction with a total IgA level. This test is very sensitive for identifying someone with celiac disease, particularly when symptoms are present. It is a little less predictive for celiac disease when it is used to proactively screen someone based solely on a genetic risk.
Do you see a lot of people with T1D and Celiac Disease? What percentage of your patients have both diseases?
The reason why T1D and CD tend to coexist is due to shared genetics. In general, about 8-10% of those with T1D will develop evidence of celiac disease autoimmunity. When you look at it the other way, the percentage of those with CD who subsequently develop T1D is much smaller, for a variety of reasons, but the risk is estimated to be about 1-2%.
How does Celiac Disease affect someone’s diabetes management?
Having CD that is untreated could result in unstable blood glucose control and more hypoglycemic events. Coexisting untreated CD can also compound risk for metabolic bone disease and microvascular complications.
What is the most common complaint or challenge you hear about having Celiac Disease?
One of the most common challenges that families and patients have with managing their CD is being able to stay safe when traveling to new places.
What are the long-term effects of celiac disease?
There are many potential long-term complications that can occur with untreated celiac disease, including osteoporosis and fractures, neurologic complications and an increased risk of certain malignancies. However, these complications occur in some, but not all untreated patients, and we are unable to predict who will develop them.
What is one major misconception of having Celiac Disease?
I think that one common misconception about CD is that a patient only needs to be gluten-free enough to control symptoms. At least in Pediatrics, we try to have our children with CD maintain as strict of a grain-free diet (GFD) as possible, with hopes of minimizing the possibility of long-term complications.
What advice would you give to a patient newly diagnosed with Celiac Disease?
Starting a GFD can be overwhelming – remember that this is more like a “marathon” rather than a “sprint.” Start off with the major sources of gluten first, then deal with the hidden gluten sources and cross contact afterwards. But keep in mind that the long-term goal is to be as strict as possible with the GFD.
Dr. Edwin Liu is a pediatric gastroenterologist at Children’s Hospital Colorado and the director of the Colorado Center for Celiac Disease.
Comment below and tell us your story about how CD changes your diabetes management!