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Celiac Disease Q&A With Dr. Stefano Guandalini, MD

Stefano Guandalini, MD

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Celiac disease is an autoimmune disease that affects at least 3 million people in the US, and many of them are undiagnosed. Because there are hundreds of symptoms, and in some cases, no symptoms at all — it can be incredibly challenging to diagnose, and leaves patients with a flood of questions.

In support of Celiac Disease Awareness Month, we tackled your burning questions in partnership with our medical advisor and internationally recognized expert on celiac, Stefano Guandalini, MD.

Screening for celiac & diagnosis

Q: Is celiac something you are born with or is it triggered in a person by some environmental exposure?

A: Great question! You are born with the genes that you have right now. However, there’s something called “epigenetics” - meaning how the environment shapes your genes that you’ve been given since birth.

Almost 40% of the general population have the most common genes for celiac disease, but you have to have exposure to gluten (the only necessary environmental factor), and one or more of certain triggers to “turn on” the immune system and trigger the reaction to gluten that defines celiac disease. Among these factors, research has identified primarily viruses (affecting in early life the intestines as well as the respiratory system), but also stress, surgery, or even a pregnancy can trigger celiac disease. 

Q: I had a biopsy and was diagnosed with celiac disease. My confusion is over how I can have celiac disease if I do not have the genetic marker for it. This is based on my 23&Me genetic testing result.  

A: Genes are tricky! We have only recently (compared to the time we’ve known about celiac) understood the most common genes related to celiac disease. It’s indeed extremely rare (but not impossible) that you can have celiac without having any of the HLA haplotypes tested for celiac disease.

Now, one must add that the testing performed by 23&Me, while they have done a great job to help people understand their risk of celiac disease as well as of so many more conditions, may not be as extensive as that performed by a geneticist-associated lab that would run a more detailed research.

Q: My question involves my 7 year old grandson. His mother has celiac disease as does my grandson's brother. My grandson has had "borderline" results on labs, most recently in the past year. He had a negative endoscopy at age 4. He is completely asymptomatic with excellent growth. At what point might repeat endoscopy and biopsy be advisable? 

A: It depends on whether or not he has symptoms and even more on what you mean by ‘borderline results' on their lab work. What labs were run? What are their results and what is the range of normal given by the specific lab for each test?. Without this information, I can’t give any meaningful recommendation, but your gastroenterologist can!

Q: I just had a negative blood test at 11 weeks into a gluten challenge. My GI will scope me next month. If it is negative, should I continue the gluten challenge? I have the gene and symptoms, my daughter is celiac and my mother had Sjogren's Syndrome and Rheumatoid Arthritis, and her doctors assumed she was celiac as well, though she died before getting a firm diagnosis. I want to know if I have celiac so I can avoid autoimmune diseases and further complications.

A: If the upcoming scope, done after more than 3 months on daily gluten will be negative, then I don’t think prolonging the challenge would be necessary; celiac disease would be excluded and eating gluten or not would be your free choice. If you then choose not to continue eating gluten, know that if you want to get retested in the future you will need to go back on a gluten challenge.

From your question, it seems that you are inclined to believe that if you turn out to be celiac, going gluten-free would prevent you from other autoimmune diseases and further complications. While a GFD would of course be needed and can prevent specific complications, whether this can also prevent autoimmune conditions is not firmly proven.

Q: My blood work does not indicate celiac, yet I am still having symptoms. Perhaps my next step is to eliminate gluten from my diet. How long would you recommend I do that to see if my symptoms go away?

A: Never begin a GFD without having firmly ruled out or in a diagnosis of celiac disease! This would only cloud the waters and make any further diagnostic and therapeutic approach murky. Your symptoms may not be linked to gluten, as there are a myriad of disorders that can mimic celiac.

Furthermore, blood work is only part of the story - if your doctor strongly suspects celiac, even in the presence of negative blood work (a rare but documented circumstance), then your doctor may opt for an upper endoscopy with biopsy. Keep in mind that you still must eat gluten to have accurate blood test and endoscopy results. If you are eating gluten and still have a negative blood test and endoscopy then you don’t have celiac, and at that point eating a gluten-containing or a gluten-free diet is purely your choice.

Q: I have tested 'unlikely' for celiac. A colonoscopy also didn't show celiac disease, but did show diverticulosis. However, I have a strong family history of celiac and I cannot eat gluten. Gluten causes IBS-like problems, severe bloating, stomach cramps and body-wide pain.I do have Hashimoto's and I know there is a connection. Is it possible to have celiac disease even though those two tests didn't show anything significant? Or is it truly just an intolerance?

A: First, it’s important to make sure you were tested properly. You only mentioned having a colonoscopy. However, celiac disease does not affect the colon (with rare exceptions), so a colonoscopy is not recommended to diagnose celiac disease. An upper endoscopy, with biopsies taken from the duodenum, however, is key to diagnosis. Secondly, you might have been eating gluten-free at the time of the blood work, but instead you need to be on a gluten-containing diet for it to be accurate.

Oftentimes, a doctor not familiar with celiac will test patients who are already avoiding gluten, and thus the tests are not accurate. Finally, could you perhaps have an intolerance, the so-called “Non-Celiac Wheat Sensitivity”? Entirely possible! But for this entity there is no diagnostic test; so we can conclude with this diagnosis only after celiac has been properly ruled out and you find the GFD to be really beneficial.

Q: I’ve been battling something for over ten years. Every time I ate pasta or wheat ingredients I would get sick out of both ends simultaneously. My attacks were very violent and I had my gallbladder removed. Since surgery my attacks have decreased significantly. Yet, I still have an occasional attack. I decided to take a celiac disease test, and my results are negative and I am unsure what to do next to get some answers. 

A: The negative blood results might have been due to you avoiding gluten. It’s critically important to be tested for celiac disease while on a gluten-containing diet to have accurate results. The nature of the symptoms and their acute occurrence would rather suggest a wheat allergy. I would most definitely recommend being seen by a gastroenterologist who is familiar with diagnosing celiac disease and wheat allergy.  

Q: How should I convince my family members to get tested for celiac disease? I'm the first in the family with a celiac diagnosis, but we have a history of autoimmune illnesses. Nobody wants to have to go gluten-free because of the social and financial burdens of the gluten-free diet.

A: I completely understand, getting the news of a diagnosis of an autoimmune disease can be scary - and expensive. However, it’s important to be properly diagnosed. Without a proper diagnosis, a person with undiagnosed celiac disease can face many issues like nutritional deficiencies, osteoporosis or even some forms of cancer, including lymphoma. Celiac disease is serious and should be treated seriously - including diagnosing first degree relatives that are at an increased risk. Trying to avoid the burden of the diet and instead pay a serious medical price does not seem logical! 

Q: My daughter started with multiple food allergies as a child, then as a teen was diagnosed with celiac disease. In her twenties, she developed eosinophilic esophagitis (EoE). She has added foods that cause EoE symptoms at times when she was probably getting gluten contamination.  My question is, do you think people with multiple food allergies or EoE should be screened for celiac disease? 

A: Interesting question! Indeed, even though Eosinophilic Esophagitis and celiac disease follow completely different pathways to develop, they can indeed co-exist. At the University of Chicago, we were among the first to document this association.

We also recently showed in a series of children with both EoE and celiac, that in one third of the cases eliminating gluten only would bring both conditions in remission. So, my answer is yes, people with EoE should be tested for celiac; and indeed probably most are, because at the time of the upper endoscopy biopsies are typically taken not just from the esophagus, but also from stomach and duodenum. 

Q: Can celiac soon be diagnosed with methods other than biopsy - e.g., HLA tetramers

A: Quite possible and exciting indeed! HLA tetramers and other laboratory markers are being investigated to this aim, but none are ready for application. That said, since almost a decade the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) promulgated new, evidence-based, diagnostic guidelines for children (updated in 2020) that allow to skip the biopsy and still reach a 100% accurate diagnosis when certain criteria (mostly based on results of blood work) are met. Adult societies might be on their way to reach similar conclusions in the future, so stay tuned!

Q: Can celiac antibodies be positive for reasons other than autoimmune celiac, and how to help immunologists differentiate/diagnose without need for biopsy?   

A: Celiac disease screening biomarkers are very sensitive and also specific to celiac disease. However, there are a few biomarkers that can be related to other conditions. For example, tTG-IgA can produce false positives for those with Type 1 Diabetes, Hashimoto’s, Crohn’s disease or autoimmune liver conditions. This is why each patient is different and after a positive result there is a need for a thorough, global assessment that includes family history and symptoms by an experienced physician before moving forward with a biopsy to diagnose celiac disease.

Celiac symptoms

Q: What does celiac disease damage?

A: Celiac disease damages primarily the villi of the small intestines. Because it blunts the villi, it prevents them from absorbing vital nutrients, leading to malnutrition and deficiencies. However, the inflammation caused by gluten while originating in the intestine, it ends up involving also other systems and - if left untreated for years - can cause damage to the joints, the liver, the bones, the heart, the brain and the kidneys, leading therefore to long term damage throughout the body. Thankfully the gluten-free diet helps greatly, in the vast majority of patients, to restore normal villi and eventually bring in remission many if not all of the systemic symptoms.

That all said, you need to know that there are different strategies being actively pursued to find alternative treatments and even one day finding a real cure. 

Q: Are there any known effects on ovarian reserve/fertility if on long-term, strict GF diet as a celiac? Different from infertility secondary to undiagnosed/mismanaged celiac.

A: Evidence suggests that women with undiagnosed celiac disease have an increased risk of infertility, pre-term birth and spontaneous miscarriage. However, there is no concrete research that I have seen about infertility after a strict gluten-free diet. But, studies have shown that women with celiac disease have an increased risk for polycystic ovarian syndrome and endometriosis, which might affect fertility. 

Q: My teen son's dentist has recommended he be tested because many of his adult teeth have spots with no enamel. Is this a common sign of celiac disease? 

A: Yes! Dental enamel defects are a common dental manifestation of celiac disease. Unfortunately, these are permanent and do not get better on a gluten-free diet. Other symptoms that a dentist might see that are from celiac include recurrent canker sores (or ulcers inside the mouth). 

Q: If I have celiac but have no symptoms or negative side effects at all, for what reasons should I not consume gluten?

A: Because your immune system does not care if you have or don’t have outward-facing symptoms. Your immune system is mobilized by gluten and keeps damaging the villi and many other systems outside the intestine, whether you experience symptoms or not.

A study on many hundreds of celiac individuals that were followed in Italy showed that those who chose to keep eating gluten had overall a significantly lower life expectancy compared to celiacs on the gluten-free diet. Anyone diagnosed with celiac disease - even without symptoms - should be on a strict gluten free diet. 

Q: As a celiac, I still have high antibodies despite a strict gluten-free diet. Is this refractory celiac or contamination? What do you recommend as the next steps?   

A: Thankfully, refractory celiac disease is rare. Typically if you have high antibodies it’s due from gluten contamination. I would evaluate your diet with the help of a skilled dietitian, including any dining out at a restaurant. Furthermore, consider that the decline of the antibodies may be slow, and their complete normalization depends also on how high they were at the beginning of the diet. For instance, if TTG were - say - 20 times higher than normal at the start, chances are they won’t be back to normal range for another couple of years, and sometimes even more. Patience is a virtue with celiac disease - along with a strict gluten-free diet. 

Q: Is it normal to get a lot of acid reflux when you have celiac? I found out I had celiac when I all of a sudden felt like something was blocking my airway every time I ate. My esophagus was swollen so when they did the endoscopy, my biopsy said I had celiac.

A: First of all, yes: celiac and reflux can go hand in hand, and many celiac patients have found that the gluten-free diet is helpful. However, if you did the endoscopy they should have also taken biopsies from the esophagus and be able to tell you whether you truly had a bad reflux or rather the rarer allergic condition called Eosinophilic Esophagitis (EoE), which would also give you a feeling of narrowing when swallowing.

In fact, you can have celiac disease and EoE at the same time. Definitely follow up with your gastroenterologist if these symptoms do not improve on a gluten-free diet. 

Q: How important is avoidance of cross contamination? What makes celiac a serious disease?

A: It’s very important to avoid cross contamination when dining out, and within the home - assuming it is not 100% gluten free. The threshold for a GF food to be called indeed gluten-free is to have no more than 20ppm, that’s 20 parts per million, of gluten. This translates to about 10 mg/pound. Studies have shown that every celiac reacts to the ingestion of 50 mg of gluten per day; now these 50 mg - while almost impossible to reach by eating just GF foods as we have seen, is still a minuscule amount of gluten that can get in your plate through cross contamination.

While getting accidentally “glutened” every once in a while might not cause long-term damage, it’s important to be on a strict gluten free diet to avoid long-term issues. Even if you happen to be among the lucky ones who do not have symptoms after ingesting a minimal amount of gluten, remember that repeated ingestion may keep active celiac disease and this in turn can cause serious issues like infertility, nutrient deficiencies, bone density issues, and even cancer. 

Related illnesses

Q: Is Sjogren's Syndrome related to celiac disease? 

A: Sjogren’s Syndrome is related to celiac disease as both are autoimmune diseases, and one puts you at a slightly higher risk for getting the other. 

Q: Am at a higher risk if I caught COVID or if I’d be okay? I have no health issues except for celiac.

A: Many people with celiac disease are worried about COVID-19. A recent survey from Beyond Celiac showed that many people with celiac disease thought that they were at increased risk of getting COVID, or were unsure of their risk. Not to worry, those with celiac disease are at the same risk of getting COVID-19 as the general population. Similar safety measures should be in place, stay socially distanced and masked, unless you are fully vaccinated. The COVID-19 vaccine is safe for anyone with celiac disease. 

Q: I have read that gluten can be a problem for those with Hashimoto’s, so I had a celiac disease test, which came back as “unlikely to have celiac”. My question is, with that result, how likely am I to have a negative response to gluten, even if it is to a lesser degree that full blown celiac disease?

A: First you need to make sure that you were eating a gluten-containing diet when you were first screened for celiac disease. If that was the case, then you can continue to eat gluten if your blood work was negative, as this would basically rule out celiac disease. If you are experiencing symptoms while eating gluten, you should consult with a gastroenterologist to achieve a clear diagnosis. While there was a study suggesting that a gluten free diet might help with those with thyroid disease even in the absence of celiac disease, this is still uncertain.

Q: The same time I was diagnosed with celiac disease, I was also diagnosed with AFib.  Do you feel that there could be a connection with the two issues?

A: Yes, there appears to be a connection between celiac disease and the risk of atrial fibrillation. A review on all published studies found that there is an almost 40% increased risk of AFib with patients with celiac disease. 

A race for the cure

Q: I just want to know will this ever go away if I do everything right like eating gluten free? 

A: Unfortunately, celiac disease is a lifelong, presently incurable disease. However, if you eat a gluten free diet, you should be able to mitigate any risks, and be free from many symptoms of celiac disease and especially from its complications. 

Q: I have two adult daughters and one grandson with celiac disease. Both of my daughters saw you a number of years ago at University of Chicago and we would often talk about possible treatments on the horizon that would enable gluten intake. Nothing has come over the past 25 years and I'd be appreciative of your insights regarding potential treatments to enable gluten intake or (dare I ask?) cure. 

A: Thank you for your mention of University of Chicago and for being a past patient! While it may not seem that celiac disease research has made any momentum in the past decade, it has moved miles! Currently, there is one trial only in Phase III (the final phase) on a preparation (Larazotide) to be taken by mouth with meals that would prevent small amounts of gluten ingested from causing symptoms.

Other studies are in various stages of experimentation by several pharmaceutical companies, some in Phase II clinical trials. Unfortunately, what appeared to be the most exciting, a “therapeutic vaccine” able to restore the lost tolerance to gluten, proved to be disappointing in clinical trials, and has been abandoned. This is how science advances: by trial and error. But research does advance, and I am absolutely confident that in a few years the scenario of alternative therapies will be very rewarding!

You can read part two of our Q&A series with Dr. Stefano Guandalini here.

Updated on
August 5, 2021
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