Celiac Presentations at the National Digestive Disease Conference: May 19-22, 2002 - Summary by Laura Yick

Dr. Kelly, who is a refractory sprue specialist, had interesting insights into Celiac Disease. He first described once having a patient say to him that eating at a restaurant or food take out is the gastronomic equivalent of promiscuous and unprotected sex because (you) dont know where food has been, who else its been with, and what you might get from it. Dr. Kelly explained that his job when seeing a patient with possible Refractory Sprue is to first confirm that the patient really has Celiac Disease and is adhering to a gluten-free (gluten-free) diet. He explained that some patients would rather prefer an iron shot than adhere to a gluten-free diet and that sensitivities vary which removes another drive to say gluten-free; however, if symptomatic, he has found that the patient has the motivation to adhere. Hes even had to recruit and train dieticians to take an interest in Celiac Disease. He said that Celiac Disease or Gluten Sensitive Enteropathy is driven by activated lamina propria T-cells to whom gliadin is being presented through their T-cell receptors. In Refractory Sprue, he said that the cells are evident at intraepithelial lymphocytes rather than lamina propria lymphocytes and they no longer require gluten in order to be driven. So, theyre on auto-pilot. He emphasized that this is a rare disease and advised that doctors get a competent dietician to help patient adhere to diet.

If the concern is that the patient is adhering but is not responding, Dr. Kelly advised doctors to think of other disorders masquerading as Celiac Disease, especially if patient is IgA, EmA (anti-endomysial) negative or if not HLA DQ2 or DQ8 (common Celiac genes) positive. He added that not every flat mucosa consistent with Celiac Sprue is Gluten Sensitive Enteropathy but that there can be a differential diagnosis such as cow protein intolerance. He said that there are unusual immunologic disorders that can be mistaken for sprue or refractory sprue. He said that doctors should consider these if the patient was not IgA endomysial or human tTg (transglutaminase) antibody positive at diagnosis. He explained that the positive predictive value of those tests are so strong that really its in some ways has a higher positive predictive value than even biopsy that you dont get very, very if any false positives at least by the immunofluorescence assay. So, if theyre negative at diagnosis considering other possibilities and this is one instance where HLA typing actually may be clinically useful if you have a patient you think has Celiac Sprue but isnt behaving or responding as you would expect with a gluten free diet and you ask do they really have Sprue. If they are HLA DQ2/DQ8 negative, then the likelihood of them having gluten sensitive disease is much, much lower. He said that serology (blood tests) were helpful but not be relied upon. He said that IG antibody levels against gliadin, or tissue transglutaminase tend to drop fairly quickly usually within 2 to 3 months provided they (patient) were positive to begin with. ...The IgG takes much longer so it tends to be less useful and of course, if they are IgA deficient, they wont be IgA positive to begin with and you cant use then. Even if their antibody levels are high to begin with, and remain high, that to me means that theyre still exposed to the antigen and they still have T-cells. Their lamina propia T-cells are still being driven by the antigen. But if theyre negative, Im afraid that its not particularly sensitive and low levels of gluten exposure may result in symptoms and poor response would not necessarily be identifiable by antibody.... Dr. Kelly said that patients with subtle manifestations of Celiac Sprue who have been previously diagnosed with irritable bowel or host of other disorders are now being more frequently seen. He said that there has been a lot of discussion in the past year about Celiac Sprue being misdiagnosed as Irritable Bowel Syndrome.

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Dr. Kelly also described the circumstance that patients with Celiac Sprue show improvement both serologically (blood) and histologically (biopsy) but their symptoms persist. He said that doctors need to be aware that just because a patient has gluten sensitive enteropathy doesnt mean they cant get another gastrointestinal disorder. He gave examples such as microscopic colitis and what he called a classical association, hyperthyroidism, or something else which could also cause diarrhea and weight loss.

Dr. MacDonald, a celiac specialist, discussed new insights into the pathogenesis of Celiac Disease. Dr. MacDonald discussed primarily the role that other factors besides the DQ2 (gene) molecule, control the T-cells in the gut mucosa which produce the lesion or flat mucosa. In the genesis of the lesion, he explained how the T-cell immune response in the gut wall results in a gut shape of tall villi and short crypts which results in an increase in mucosa volume with flat mucosa and an increase in mucosa thickness. My husband, a PhD immunologist, interpreted this for me; He said that imagine the villi are the hill and the crypts are the valley. The valley is where things grow. The oldest cells are at the tip of the hill and as cells mature, they get transported up the hill. As damage occurs, the hill gets chopped down, valleys get deeper making more area for cells to replicate. Dr. MacDonald assumed that because the epithelium is turning over so fast in Celiac Disease that the lamina propria, the shape of the gut itself would be turning over, but actually the data says otherwise. The flat mucosa isnt turning over at all, ... a rather stable shape, its not really dynamic, its remodeled. He said that putting Celiacs on a gluten free diet may take them a long time to get better, because it takes a long time for this to go back because this is actually stable, its remodeled....

Dr. MacDonald explained that gliadin peptides associate with DQ2 and DQ8 molecules putting themselves into the grooves to be seen by T cells. However, he gave an instance where a particular gliadin peptide doesnt fit well into the pockets of DQ2 to be seen by T cells. Tissue Transglutaminase or Ttg deamidates (removes chemical groups on certain amino acids and allows peptide to bind to DQ2) this peptide in terms of glutamine into glutamic acid, gives a negative charge, fits very well into pocket, and binding increases 100 fold. Tightness of the binding ... controls the specificity and strength of the T-cell response.

Dr. MacDonald also described the case of a woman with cancer who was treated with interferon. He said that she had the endomysial antibodies, was DQ2 positive, and had Celiac Disease; however, he cited that the reason why the Celiac Disease was not found earlier was that interferon alpha/gamma used to treat the cancer may have precipitated clinical Celiac Disease. He added that her son was later diagnosed with Celiac Disease as well. It was also eluded to that a viral infection like a gastrointestinal flu would stimulate or produce interferon alpha.

Dr. Alessio Fasano from the Center for Celiac Research at the Univ. of Maryland also explained that its not just the gluten antigen and genes (i.e., HLA DQ2 or DQ8) but an added element like that alluded to by Dr. MacDonald such as a viral infection which can result in Celiac Disease. Dr. Fasano described a study performed on North African children who were thought to have symptoms resembling infectious disease with symptoms like anemia and diarrhea were found to have Celiac Disease at the rate of 1 in 18. He said because they have a high consumption of grains and seem to carry a high frequency of the genetic elements, he felt that non-profit organizations may intervene to help institute a gluten-free diet in this Celiac population. Dr. Fasano mentioned a study performed in Southern California which found Celiac Disease in 2 to 4% of people with symptoms or associated diseases and 5% in family members of Celiacs. Dr. Fasano stated that the overall prevalence is 1 in 266 which he said on a global scale, by far this is the most frequently genetic disease of human kind. Fasano said that in the 1970s, it was thought Celiac Disease was confined to the pediatric population but that since 1998 there has been a surge in adult versus child cases. He believes that the disease may have been overlooked in adults because adults have more atypical symptoms like anemia, osteoporosis, abortion that would NOT see a Gastroenterologist but would see an internist, reproductive OBGyn, endocrinologist, etc.

Dr. Fasano said that if the iceberg idea is diarrhea, weight loss, abdominal symptoms, you will surely crash into the iceberg, but he proposed, what about the people who have joint pain, constipation, fatigue, and so on. He said that if you are willing to see the monument of the problems, you have to get down under the water because in the vast majority of cases, Celiacs will not see a Gastroenterologist and that doctors must be aware of those under the water. Dr. Fasano during the question and answer session listened to a doctor in the audience describe a patient with diarrhea and schizophrenia whose diarrhea and schizophrenia resolved when put on a gluten-free diet. The doctor didnt know what to do with the patient but explained that the patients background, being of Irish descent, gave him a red flag into the possibility of Celiac Disease. Dr. Fasano in response described how there can be a change in behavior such as attention deficit disorder, depression, and schizophrenia. He described a theory that the epitopes of gluten could cross the intestinal barrier, cut into the bloodstream, and cross the blood brain barrier. He believes that there is a clear association between Celiac Disease and change in behavior.