Saturday, December 21, 2013

Misdiagnosis, noncompliance often culprits in refractory celiac disease

Refractory celiac disease is often the result of patients having either received an incorrect diagnosis, or their noncompliance, according to Dr. Joseph Murray of the Mayo Clinic in Rochester, Minn. “When faced with such a patient, it’s important to reconfirm the original diagnosis,” said Dr. Murray, who made his remarks during a clinical track presentation at a conference on inflammatory bowel. In cases in which the diagnosis can be confirmed and the patient is compliant, discovering if there are other conditions, and whether to intervene and how, are the important next steps, according to Dr. Murray. When patients present with symptoms of nonresponsive celiac disease, besides taking the patient’s history, which should include whether the patient has any first-degree family members with “true” celiac disease, not just family members who have chosen to stop eating gluten, “I will always ask for the original biopsies,” said Dr. Murray. In addition, original serology tests, if they were done, can confirm whether there are celiac-specific antibodies. “Gliadin antibodies are not celiac specific,” said Dr. Murray. “You can get gliadin antibodies in virtually every other disorder that affects the intestines, so they are pretty much worthless.” Better specificity comes from tissue transglutaminase or endomysial antibodies, he said at the meeting diseases sponsored by the Crohn’s & Colitis Foundation of America. Human leukocyte antigen genotyping, and whether the patient had a clinically obvious response to a gluten-free diet also will help the clinician puzzle out if the original diagnosis was correct, according to Dr. Murray. Worth noting is whether the patient has dermatitis herpetiformis, “That’s pathognomonic for celiac disease,” said Dr. Murray. For example, in the case of a 90-year-old woman whose biopsy 10 years before had been interpreted as presumptive celiac disease and who had had an initial response to a gluten-free diet, had symptoms that persisted for a decade because she’d contracted tropical sprue from annual visits to Indonesia that were not noted in her original patient history. Treated properly, her symptoms abated entirely, according to Dr. Murray. “She wasn’t exactly happy about her 10 years of living gluten free,” he said. Dangers of noncompliance As for patients who claim to follow a gluten-free diet, “That’s not true most of the time,” said Dr. Murray. “A positive serology test in a patient who’s been following a gluten-free diet for a year or more means they’re not just getting a little gluten. They’re getting a lot of gluten.” It can either be advertent or inadvertently, he said. However, serology is insensitive for lower levels of gluten contamination, but a gram of gluten, roughly one-half a slice of bread per day, can be detected, according to Dr. Murray. If noncompliance is the reason for the refractory condition, patients are at greater risk for increased mortality, osteoporosis, lymphomas, and other cancers, and psychological effects such as depression. “Eliminating the gluten may take time. Often we have to use behavioral counselors to help,” said Dr. Murray. Also key is to stay in touch with the patient. “Follow-up in patients with celiac disease is abysmal,” Dr. Murray said, “It’s almost like once the disease is diagnosed, it’s forgotten about medically.” “The complicating thing about celiac disease can be that autoimmune disorders and like disorders hang out together,” said Dr. Murray. “Complications of celiac disease also can occur in multiples.” Bacterial overgrowth, microscopic colitis, lymphoma, and systemic sclerosis associated–dysmotility are all concurrent conditions Dr. Murray reported seeing in his own practice when treating refractory celiac disease. Because lactose intolerance is also common in celiac disease, Dr. Murray said he will often advises patients to avoid dairy for a year, and then gradually add that back into the diet with good results. “Often, that will work, so I don’t even test for lactose intolerance initially,” he said. Despite all the possible etiologies for nonresponsive celiac disease, gluten exposure was found in more than a third of cases, while “true refractory celiac disease really makes up only about 10% or 11% of these nonresponsive patients,” said Dr. Murray, referring to a study on the topic (Clin. Gastroenterol. Hepatol. 2007;5:445-50). Patients with celiac disease also can have multifocal strictures in the proximal duodenum that reach the jejunum, “but rarely affect the ileum,” according to Dr. Murray. Possible lymphomas “The first thing that I think about when I see a really sick patient previously diagnosed with celiac disease several years before is, ‘Does the patient have lymphoma?’” said Dr. Murray. Ulcerative jejunoileitis typically indicates that lymphoma is imminent, although shallower ulcers are often linked to the use of NSAIDs, he said. Giant cavitating lymphadenopathy, while rare, is also a consideration, according to Dr. Murray. “A premalignant type of disorder, sometimes will respond to immunosuppressives, but often can presage the development of lymphoma,” he said. True refractory celiac disease involves symptomatic malabsorption, severe enteropathy, and a primary or secondary nonresponse to a gluten-free diet. “By definition, there should be no lymphoma,” said Dr. Murray. Refractory celiac disease is either characterized as type 1, which has a normal T-cell population and responds well to immunosuppression, or as type 2 with clonal T cells. Dr. Murray said he often uses topical budesonide to treat type 1 patients, with good results, since there is about a 90% recovery rate in this patient population. Type 2 is the most pernicious, with nearly half of patients dying within 5 years of diagnosis, either from malignant or infectious complications, according to Dr. Murray. “Type 2 refractory disease is not a trivial disease,” he said. Although most adults with celiac disease don’t heal, many are asymptomatic; however, this does not mean a patient’s risk of mortality from the disease has improved. Patients are also at greater risk for malignant complications. (Am. J. Gastroenterol. 2010;105:1412-20 [doi:10.1038/ajg.2010.10]). “We really don’t know what we should do about those asymptomatic patients,” said Dr. Murray. He noted that, “Failure to heal is not entirely benign, but it’s not refractory celiac disease,” said Dr. Murray.

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