Celiac Disease-Related Conditions: Who to Test?

Celiac disease (CeD) is a chronic immune-mediated condition triggered by gluten consumption in genetically predisposed individuals. Approximately 1% of the general population is affected by the disorder. Disease presentation is heterogeneous and, despite growing awareness among physicians and the public, it continues to be underestimated. The most effective strategy for identifying undiagnosed CeD is proactive case finding through serologic testing in high-risk groups. We reviewed the most recent evidence on the association between CeD and more than 20 conditions. In light of this review, CeD screening is recommended in individuals with (1) autoimmune disease and accompanying symptoms suggestive of CeD; (2) diseases that may mimic CeD (eg, irritable bowel syndrome [IBS], inflammatory bowel disease [IBD], and microscopic colitis); and (3) among patients with conditions with a high CeD prevalence: first-degree relatives, idiopathic pancreatitis, unexplained liver enzyme abnormalities, autoimmune hepatitis, primary biliary cholangitis, hyposplenism or functional asplenia with severe bacterial infection, type 1 diabetes mellitus, Hashimoto's thyroiditis and Graves' disease, Sjögren's syndrome, dermatitis herpetiformis, recurrent aphthous syndrome and enamel defects, unexplained ataxia, peripheral neuropathy, delayed menarche or premature menopause, Down syndrome, Turner syndrome, Williams syndrome, chronic fatigue syndrome, IgA nephropathy, and IgA deficiency. CeD serology should be the initial step in the screening process. However, for patients with any of the aforementioned disorders who are undergoing upper endoscopy, biopsies should be performed to rule out CeD.

Accuracy of a no-biopsy approach for the diagnosis of coeliac disease across different adult cohorts.

OBJECTIVE: We aimed to determine the predictive capacity and diagnostic yield of a 10-fold increase in serum IgA antitissue transglutaminase (tTG) antibody levels for detecting small intestinal injury diagnostic of coeliac disease (CD) in adult patients. DESIGN: The study comprised three adult cohorts. Cohort 1: 740 patients assessed in the specialist CD clinic at a UK centre; cohort 2: 532 patients with low suspicion for CD referred for upper GI endoscopy at a UK centre; cohort 3: 145 patients with raised tTG titres from multiple international sites. Marsh 3 histology was used as a reference standard against which we determined the performance characteristics of an IgA tTG titre of ≥10×ULN for a diagnosis of CD. RESULTS: Cohort 1: the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for IgA tTG levels of ≥10×ULN at identifying individuals with Marsh 3 lesions were 54.0%, 90.0%, 98.7% and 12.5%, respectively. Cohort 2: the sensitivity, specificity, PPV and NPV for IgA tTG levels of ≥10×ULN at identifying individuals with Marsh 3 lesions were 50.0%, 100.0%, 100.0% and 98.3%, respectively. Cohort 3: the sensitivity, specificity, PPV and NPV for IgA tTG levels of ≥10×ULN at identifying individuals with Marsh 3 lesions were 30.0%, 83.0%, 95.2% and 9.5%, respectively. CONCLUSION: Our results show that IgA tTG titres of ≥10×ULN have a strong predictive value at identifying adults with intestinal changes diagnostic of CD. This study supports the use of a no-biopsy approach for the diagnosis of adult CD.

Gluten-Free Diet Reduces Symptoms, Particularly Diarrhea, in Patients With Irritable Bowel Syndrome and Antigliadin IgG.

BACKGROUND & AIMS: Many patients with irritable bowel syndrome (IBS) perceive that their symptoms are triggered by wheat-containing foods. We assessed symptoms and gastrointestinal transit before and after a gluten-free diet (GFD) in unselected patients with IBS and investigated biomarkers associated with symptoms. METHODS: We performed a prospective study of 50 patients with IBS (ROME III, all subtypes), with and without serologic reactivity to gluten (antigliadin IgG and IgA), and 25 healthy subjects (controls) at a university hospital in Hamilton, Ontario, Canada, between 2012 and 2016. Gastrointestinal transit, gut symptoms, anxiety, depression, somatization, dietary habits, and microbiota composition were studied before and after 4 weeks of a GFD. HLA-DQ2/DQ8 status was determined. GFD compliance was assessed by a dietitian and by measuring gluten peptides in stool. RESULTS: There was no difference in symptoms among patients at baseline, but after the GFD, patients with antigliadin IgG and IgA reported less diarrhea than patients without these antibodies (P = .03). Compared with baseline, IBS symptoms improved in 18 of 24 patients (75%) with antigliadin IgG and IgA and in 8 of 21 patients (38%) without the antibodies. Although constipation, diarrhea, and abdominal pain were reduced in patients with antigliadin IgG and IgA, only pain decreased in patients without these antibodies. Gastrointestinal transit normalized in a higher proportion of patients with antigliadin IgG and IgA. Anxiety, depression, somatization, and well-being increased in both groups. The presence of antigliadin IgG was associated with overall reductions in symptoms (adjusted odds ratio compared with patients without this antibody, 128.9; 95% CI, 1.16-1427.8; P = .04). Symptoms were reduced even in patients with antigliadin IgG and IgA who reduced gluten intake but were not strictly compliant with the GFD. In controls, a GFD had no effect on gastrointestinal symptoms or gut function. CONCLUSIONS: Antigliadin IgG can be used as a biomarker to identify patients with IBS who might have reductions in symptoms, particularly diarrhea, on a GFD. Larger studies are needed to validate these findings. ClinicalTrials.gov: NCT03492333.

Measurement of Forearm Bone Density by Dual Energy X-Ray Absorptiometry Increases the Prevalence of Osteoporosis in Men With Celiac Disease.

BACKGROUND & AIMS: Guidelines advise measurement of bone mineral density (BMD) in patients with a diagnosis of celiac disease. The lumbar spine (LS) and hip sites are usually measured. Although skeletal sites rich in trabecular bone are believed to be vulnerable to osteoporosis in patients with celiac disease, most studies have not measured the cortical distal 1/3-radius. METHODS: We collected data from 721 patients (mean age, 43.6 years; 68.4% female) with celiac disease who underwent 3-site dual energy x-ray absorptiometry (DXA, at a median 1.22 years after diagnosis). We assessed skeletal site- and sex-specific osteoporosis prevalence and the incremental utility of 1/3-radius measurement by DXA. RESULTS: Mean T- and Z-scores were normal in patients, but 43.3% had osteopenia and 19.6% had osteoporosis. Osteoporosis was found in 12.1% of patients at the LS, 5.3% of patients at the total hip, 7.6% of patients at the femoral neck, and 11.5% of patients at the 1/3-radius. A greater degree of villous atrophy at diagnosis was associated with male sex and lower T-scores at the 1/3-radius (P = .03), but not other skeletal sites. Isolated forearm osteoporosis was detected in 4.9% of patients. A higher proportion of patients with isolated forearm osteoporosis were male and had a greater weight and body mass index (all P < .01, compared to patients with osteoporosis only at other sites). Z-scores were lower at the LS and 1/3-radius and osteoporosis was more common in men than women. In men, the 1/3-radius was the most frequent site for osteoporosis. Among patients 50 years or older, isolated forearm osteoporosis was present in 10.7%. CONCLUSIONS: Based on DXA analysis of patients with celiac disease, the prevalence of osteoporosis appears to be underestimated-particularly in men when BMD at the 1/3-radius is not measured. Degree of villous atrophy is associated with BMD at the 1/3-radius and nearly 5% of patients have osteoporosis limited to that site. Recommendations for osteoporosis screening in patients with celiac disease should include measurement of the distal 1/3-radius in addition to the hip and LS.

A Prospective Study on Cognitive Impairment in Middle-aged Adults With Newly Diagnosed Celiac Disease.

AIMS: Our objectives were to: (1) determine whether celiac disease (CD) patients have cognitive impairment at diagnosis; and (2) compare their cognitive performance with nonceliac subjects who have similar chronic symptoms and healthy controls. MATERIALS AND METHODS: Fifty adults (age range: 18 to 50 y) with symptoms and signs compatible with CD were enrolled in a prospective cohort irrespective of the final diagnosis. At baseline, all individuals underwent cognitive functional and psychological evaluation. CD patients were compared with subjects in whom CD was ruled out and with healthy controls matched by sex, age, and years of schooling. RESULTS: Thirty-three subjects (66%) were diagnosed with CD. Compared with the healthy controls (n=26), CD cases and disease controls (n=17; mostly irritable bowel syndrome) had impaired cognitive performance (P=0.02 and P=0.04, respectively), functional impairment (P<0.01), and higher depression (P<0.01). CD patients had similar cognitive performance and anxiety, but nonsignificant lower depression scores compared with disease controls. CONCLUSIONS: Abnormal cognitive functions detected in newly diagnosed CD adult patients seem not to be disease specific. Our results suggest that cognitive dysfunction could be related to the presence of prolonged symptoms due to a chronic disease.

Bifidobacterium infantis NLS Super Strain Reduces the Expression of α-Defensin-5, a Marker of Innate Immunity, in the Mucosa of Active Celiac Disease Patients.

BACKGROUND: We have previously shown a reduction of gastrointestinal symptoms after the oral administration of Bifidobacterium infantis Natren Life Start super strain (NLS-SS) in untreated celiac disease (CD) patients. The symptomatic improvement was not associated with changes in intestinal permeability or serum levels of cytokines, chemokines, or growth factors. Therefore, we hypothesized that the beneficial symptomatic effect observed previously in patients with CD treated with B. infantis may be related to the modulation of innate immunity. GOALS: To investigate the potential mechanisms of a probiotic B. infantis Natren Life Start super strain on the mucosal expression of innate immune markers in adult patients with active untreated CD compared with those treated with B. infantis×6 weeks and after 1 year of gluten-free diet (GFD). METHODS: Numbers of macrophages and Paneth cells and α-defensin-5 expression were assessed by immunohistochemistry in duodenal biopsies. RESULTS: We showed that GFD decreases duodenal macrophage counts in CD patients more effectively than B. infantis. In contrast, B. infantis decreases Paneth cell counts and expression of α-defensin-5 in CD (P<0.001). CONCLUSIONS: The results identify differential innate immune effects of treatment with B. infantis compared with 1 year of GFD. Further studies are needed to investigate synergistic effects of GFD and B. infantis supplementation in CD.

Advances in diagnosis and management of celiac disease.

Celiac disease is an autoimmune disorder that is induced by dietary gluten in genetically predisposed individuals. It has a prevalence of approximately 1% in many populations worldwide. New diagnoses have increased substantially, owing to increased awareness, better diagnostic tools, and probable real increases in incidence. The breadth of recognized clinical presentations continues to expand, making the disorder highly relevant to all physicians. Newer diagnostic tools, including serologic tests for antibodies against tissue transglutaminase and deamidated gliadin peptide, greatly facilitate diagnosis. Tests for celiac-permissive HLA-DQ2 and HLA-DQ8 molecules are useful in defined clinical situations. Celiac disease is diagnosed by histopathologic examination of duodenal biopsy specimens. However, according to recent controversial guidelines, a diagnosis can be made without a biopsy in certain circumstances, especially in children. Symptoms, mortality, and risk for malignancy each can be reduced by adherence to a gluten-free diet. This treatment is a challenge, however, because the diet is expensive, socially isolating, and not always effective in controlling symptoms or intestinal damage. Hence, there is increasing interest in developing nondietary therapies.

Extraintestinal manifestations of celiac disease.

Case finding for celiac disease (CD) is becoming increasingly common practice and is conducted in a wide range of clinical situations ranging from the presence of gastrointestinal symptoms to failure to thrive in children, prolonged fatigue, unexpected weight loss and anemia. Case finding is also performed in associated conditions, such as autoimmune thyroid disease, dermatitis herpetiformis and type 1 diabetes, as well as in patients with irritable bowel syndrome, unexplained neuropsychiatric disorders and first-degree relatives of patients with diagnosed CD. This aggressive active case finding has dramatically changed the clinical characteristics of newly diagnosed patients. For instance, higher numbers of patients who present with extraintestinal symptoms are now being diagnosed with CD. Current recommendations state that due to a high risk for complications if the disease remains undiagnosed, patients with extraintestinal symptoms due to CD require appropriate diagnosis and treatment. Despite criticism regarding the cost-effectiveness of case finding in CD, such an aggressive approach has been considered cost-effective for high-risk patients. The diagnosis of CD among patients with extraintestinal symptoms requires a high degree of awareness of the clinical conditions that carry a high risk for underlying CD. Also, understanding the correct use of specific serology and duodenal histology is key for an appropriate diagnostic approach. Both procedures combined are able to confirm diagnosis in the vast majority of cases. However, in certain circumstances, serology and even duodenal histology cannot confirm or rule out CD. A common cause of negative IgA serology is IgA deficiency. For such eventuality, IgG-based serological tests can help confirm the diagnosis. Importantly, some histologically diagnosed cases still remain seronegative despite exclusion of IgA deficiency. On the other hand, duodenal histology may be normal despite the presence of CD-specific antibodies and active CD. This has been clearly demonstrated in some cases of untreated dermatitis herpetiformis, but may also be due to the patchy condition of CD or lesions that are not adequately recognized by nonexpert endoscopists and/or pathologists. The effectiveness of agluten-free diet depends on the clinical end point addressed. A good example is the outcome of bone loss. While risk for fracture normalizes after the first year of dietary treatment, bone parameters measured by densitometry may not be normalized in the long-term follow-up. Moreover, it is still unclear how far an early gluten-free diet will positively affect associated autoimmune diseases like type 1 diabetes and autoimmune thyroiditis.

Diagnosis and management of adult coeliac disease: guidelines from the British Society of Gastroenterology.

A multidisciplinary panel of 18 physicians and 3 non-physicians from eight countries (Sweden, UK, Argentina, Australia, Italy, Finland, Norway and the USA) reviewed the literature on diagnosis and management of adult coeliac disease (CD). This paper presents the recommendations of the British Society of Gastroenterology. Areas of controversies were explored through phone meetings and web surveys. Nine working groups examined the following areas of CD diagnosis and management: classification of CD; genetics and immunology; diagnostics; serology and endoscopy; follow-up; gluten-free diet; refractory CD and malignancies; quality of life; novel treatments; patient support; and screening for CD.

Novel role of the serine protease inhibitor elafin in gluten-related disorders.

OBJECTIVES: Elafin, an endogenous serine protease inhibitor, modulates colonic inflammation. We investigated the role of elafin in celiac disease (CD) using human small intestinal tissues and in vitro assays of gliadin deamidation. We also investigated the potential beneficial effects of elafin in a mouse model of gluten sensitivity. METHODS: Epithelial elafin expression in the small intestine of patients with active CD, treated CD, and controls without CD was determined by immunofluorescence. Interaction of elafin with human tissue transglutaminase-2 (TG-2) was investigated in vitro. The 33-mer peptide, a highly immunogenic gliadin peptide, was incubated with TG-2 and elafin at different concentrations. The degree of deamidation of the 33-mer peptide was analyzed by liquid chromatography-mass spectrometry. Elafin was delivered to the intestine of gluten-sensitive mice using a recombinant Lactococcus lactis vector. Small intestinal barrier function, inflammation, proteolytic activity, and zonula occludens-1 (ZO-1) expression were assessed. RESULTS: Elafin expression in the small intestinal epithelium was lower in patients with active CD compared with control patients. In vitro, elafin significantly slowed the kinetics of the deamidation of the 33-mer peptide to its more immunogenic form. Treatment of gluten-sensitive mice with elafin delivered by the L. lactis vector normalized inflammation, improved permeability, and maintained ZO-1 expression. CONCLUSIONS: The decreased elafin expression in the small intestine of patients with active CD, the reduction of 33-mer peptide deamidation by elafin, coupled to the barrier enhancing and anti-inflammatory effects observed in gluten-sensitive mice, suggest that this molecule may have pathophysiological and therapeutic importance in gluten-related disorders.

Issues associated with the emergence of coeliac disease in the Asia­Pacific region: a working party report of the World Gastroenterology Organization and the Asian Pacific Association of Gastroenterology.

BACKGROUND AND AIM: Once thought to be uncommon in Asia, coeliac disease (CD) is now being increasingly recognized in Asia­Pacific region. In many Asian nations, CD is still considered to be either nonexistent or very rare. In recognition of such heterogeneity of knowledge and awareness, the World Gastroenterology Organization and the Asian Pacific Association of Gastroenterology commissioned a working party to address the key issues in emergence of CD in Asia. METHODS: A working group consisting of members from Asia­Pacific region, Europe, North America, and South America reviewed relevant existing literature with focus on those issues specific to Asia­Pacific region both in terms of what exists and what needs to be done. RESULTS: The working group identified the gaps in epidemiology, diagnosis, and management of CD in Asian­Pacific region and recommended the following: to establish prevalence of CD across region, increase in awareness about CD among physicians and patients, and recognition of atypical manifestations of CD. The challenges such as variability in performance of serological tests, lack of population-specific cut-offs values for a positive test, need for expert dietitians for proper counseling and supervision of patients, need for gluten-free infrastructure in food supply and creation of patient advocacy organizations were also emphasized. CONCLUSIONS: Although absolute number of patients with CD at present is not very large, this number is expected to increase over the next few years or decades. It is thus appropriate that medical community across the Asia­Pacific region define extent of problem and get prepared to handle impending epidemic of CD.

The Oslo definitions for coeliac disease and related terms.

OBJECTIVE: The literature suggests a lack of consensus on the use of terms related to coeliac disease (CD) and gluten. DESIGN: A multidisciplinary task force of 16 physicians from seven countries used the electronic database PubMed to review the literature for CD-related terms up to January 2011. Teams of physicians then suggested a definition for each term, followed by feedback of these definitions through a web survey on definitions, discussions during a meeting in Oslo and phone conferences. In addition to 'CD', the following descriptors of CD were evaluated (in alphabetical order): asymptomatic, atypical, classical, latent, non-classical, overt, paediatric classical, potential, refractory, silent, subclinical, symptomatic, typical, CD serology, CD autoimmunity, genetically at risk of CD, dermatitis herpetiformis, gluten, gluten ataxia, gluten intolerance, gluten sensitivity and gliadin-specific antibodies. RESULTS: CD was defined as 'a chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals'. Classical CD was defined as 'CD presenting with signs and symptoms of malabsorption. Diarrhoea, steatorrhoea, weight loss or growth failure is required.' 'Gluten-related disorders' is the suggested umbrella term for all diseases triggered by gluten and the term gluten intolerance should not to be used. Other definitions are presented in the paper. CONCLUSION: This paper presents the Oslo definitions for CD-related terms.

Guidelines for best practices in monitoring established coeliac disease in adult patients.

Coeliac disease (CeD) is an immunological disease triggered by the consumption of gluten contained in food in individuals with a genetic predisposition. Diagnosis is based on the presence of small bowel mucosal atrophy and circulating autoantibodies (anti-type 2 transglutaminase antibodies). After diagnosis, patients follow a strict, life-long gluten-free diet. Although the criteria for diagnosis of this disease are well defined, the monitoring phase has been studied less and there is a lack of specific guidelines for this phase. To develop a set of clinical guidelines for CeD monitoring, we followed the Grading of Recommendations Assessment, Development and Evaluation methodology. Statements and recommendations with the level of evidence were developed and approved by the working group, which comprised gastroenterologists, pathologists, dieticians and biostatisticians. The proposed guidelines, endorsed by the North American and European coeliac disease scientific societies, make recommendations for best practices in monitoring patients with CeD based on the available evidence. The evidence level is low for many topics, suggesting that further research in specific aspects of CeD would be valuable. In conclusion, the present guidelines support clinicians in improving CeD treatment and follow-up and highlight novel issues that should be considered in future studies.

Exploratory, randomized, double-blind, placebo-controlled study on the effects of Bifidobacterium infantis natren life start strain super strain in active celiac disease.

BACKGROUND/AIMS: The aim of this exploratory trial was to establish if the probiotic Bifidobacterium natren life start (NLS) strain strain may affect the clinical course and pathophysiological features of patients with untreated celiac disease (CD). Positive findings would be helpful in directing future studies. METHODS: Twenty-two adult patients having 2 positives CD-specific tests were enrolled. Patients were randomized to receive 2 capsules before meals for 3 weeks of either Bifidobacterium infantis natren life start strain super strain (Lifestart 2) (2×10(9) colony-forming units per capsule) (n = 12) or placebo (n = 10), whereas they also consumed at least 12 g of gluten/day. A biopsy at the end of the trial confirmed CD in all cases. The primary outcome was intestinal permeability changes. Secondary endpoints were changes in symptoms and the Gastrointestinal Symptom Rating Scale, and in immunologic indicators of inflammation. RESULTS: The abnormal baseline intestinal permeability was not significantly affected by either treatment. In contrast to patients on placebo, those randomized to B. infantis experienced a significant improvement in Gastrointestinal Symptom Rating Scale (P = 0.0035 for indigestion; P = 0.0483 for constipation; P = 0.0586 for reflux). Final/baseline IgA tTG and IgA DGP antibody concentration ratios were lower in the B. infantis arm (P = 0.055 for IgA tTG and P = 0.181 for IgA DGP). Final serum macrophage inflammatory protein-1ß increased significantly (P < 0.04) only in patients receiving B. infantis. The administration of B. infantis was safe. CONCLUSIONS: The study suggests that B. infantis may alleviate symptoms in untreated CD. The probiotic produced some immunologic changes but did not modify abnormal intestinal permeability. Further studies are necessary to confirm and/or expand these observations.

Comparison of weekly gluten immunogenic peptide measurement and conventional tools to assess adherence to the gluten-free diet in celiac disease: An observational prospective study.

BACKGROUND: Adherence to the gluten-free diet (GFD) is critical to achieving symptom control and mucosal healing in celiac disease (CeD), but its assessment is difficult. OBJECTIVES: We sought to compare stool gluten immunogenic peptides (GIPs) measurements over a 4-wk period with conventional tools commonly used to monitor compliance with a GFD. METHODS: Consecutive adult patients with CeD attending the Small Bowel Section of the Buenos Aires Gastroenterology Hospital were invited to this observational study and were instructed to collect stool samples on Fridays for 4 consecutive weeks. Weekly mean stool GIP concentration was measured was estimated. GIP results were compared with a self-assessment scale of adherence, specific CeD serology, the celiac symptom index, and the assessment by an expert dietitian. RESULTS: Fifty-three CeD patients were enrolled and those with stool GIP ≥0.65 µg/g/wk (n = 13; 24.5%) had higher serum concentrations of IgA deamidated gliadin peptides (DGPs) antibodies [69 (29-109) compared with 14 (13-29); P = 0.0005] and IgA tissue transglutaminase [42 (14-200) compared with 10 (7-16); P = 0.02], higher proportion of cases with IgA DGP antibodies >20 AU/mL (84.6% compared with 33.3%; P = 0.002), and a higher self-estimated adherence score [5 (4-9) compared with 9 (7-10); P = 0.003]. GIP did not correlate with celiac symptom index scores (55.6% compared with 30.8%; P = 0.9). Expert dietitian assessment identified 69% [odds ratio (OR): 5.25; 95% CI: 1.1-27.2; P = 0.01] of nonadherent cases when high stool GIP. Logistic regression analysis determined that IgA DGP (adjusted OR: 1.1; 95% CI: 1.01-1.11; P = 0.02) and males (adjusted OR: 28.3; 95% CI: 1.1-722.6; P = 0.04) were independently associated with excessive gluten exposure. CONCLUSIONS: Weekly stool GIP identifies gluten exposure that is not always detected by commonly used GFD adherence assessment methods. The higher the concentration of stool GIP, the better the predictive value of serology and dietitian interviews. Stool GIP is a useful and practical test for GFD monitoring, particularly for risky gluten exposure in real-life scenarios.

Spectrum of gluten-related disorders: consensus on new nomenclature and classification.

A decade ago celiac disease was considered extremely rare outside Europe and, therefore, was almost completely ignored by health care professionals. In only 10 years, key milestones have moved celiac disease from obscurity into the popular spotlight worldwide. Now we are observing another interesting phenomenon that is generating great confusion among health care professionals. The number of individuals embracing a gluten-free diet (GFD) appears much higher than the projected number of celiac disease patients, fueling a global market of gluten-free products approaching $2.5 billion (US) in global sales in 2010. This trend is supported by the notion that, along with celiac disease, other conditions related to the ingestion of gluten have emerged as health care concerns. This review will summarize our current knowledge about the three main forms of gluten reactions: allergic (wheat allergy), autoimmune (celiac disease, dermatitis herpetiformis and gluten ataxia) and possibly immune-mediated (gluten sensitivity), and also outline pathogenic, clinical and epidemiological differences and propose new nomenclature and classifications.