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.

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.

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.

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.

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.

Effect of Bifidobacterium infantis NLS super strain in symptomatic coeliac disease patients on long-term gluten-free diet - an exploratory study

Bifidobacterium infantis NLS super strain (B. infantis NLS-SS) was previously shown to alleviate gastrointestinal symptoms in newly diagnosed coeliac disease (CD) patients consuming gluten. A high proportion of patients following a gluten-free diet experiences symptoms despite dietary compliance. The role of B. infantis in persistently symptomatic CD patients has not been explored. The aim of the study was to evaluate the effect of B. infantis NLS-SS on persistent gastrointestinal symptoms in patients with CD following a long-term GFD. We conducted a randomised, cross-over, double-blind, placebo-controlled trial in symptomatic adult CD patients on a GFD for at least two years. After one-week run-in, patients were randomised to B. infantis NLS-SS or placebo for 3 weeks with cross-over after a 2-week wash-out period. We estimated changes (Δ) in celiac symptom index (CSI) before and after treatment. Stool samples were collected for faecal microbiota analysis (16S rRNA sequencing). Gluten immunogenic peptide (GIP) excretion in stool and urine samples was measured at each study period. Eighteen patients were enrolled; six patients were excluded due violations in protocol. For patients with the highest clinical burden, CD symptoms were lower in probiotic than in placebo treatment (P=0.046). B. infantis and placebo treated groups had different microbiota profiles as assessed by beta diversity clustering. In probiotic treated groups, we observed an increase in abundance of B. infantis. Treatment with B. infantis was associated with decreased abundance of Ruminococcus sp. and Bifidobacterium adolescentis. GIP excretion in stools and urine was similar at each treatment period. There were no differences in adverse effects between the two groups. B. infantis NLS-SS improves specific CD symptoms in a subset of highly symptomatic treated patients (GFD). This is associated with a shift in stool microbiota profile. Larger studies are needed to confirm these findings. ClinicalTrials.gov: NCT03271138.

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.

Toward New Paradigms in the Follow Up of Adult Patients With Celiac Disease on a Gluten-Free Diet

Gluten free diet is the only available treatment for celiac disease (CeD). Patients with CeD who do not adhere to a strict gluten-free diet (GFD) have been found to have complications involving nutritional deficiencies, increased risk of bone fractures, increased risk of mortality, and certain types of cancers. Complete removal of gluten from the diet in a patient with CeD often results in symptomatic, serologic, and histologic remission. However, strict compliance with the diet is challenging. Long-term follow-up care is needed to assure treatment compliance and positive health outcomes. Monitoring celiac specific serology, nutrient deficiencies, bone mineral density, and assessment of GFD compliance have been recommended in clinical practice. However, there is no consensus on which specific tests and how often they should be performed during the follow up. Here, we have performed a review of the literature on current strategies to follow up patients with CeD. There are new tools for monitoring adherence to the GFD which could change some paradigms in following up treated patients.

Follow-up of Celiac Disease

Currently, the only effective treatment for celiac disease is complete removal of gluten from the diet. However, patients need to follow a strict gluten-free diet that results in symptomatic, serologic, and histologic remission in most patients. Histologic remission is usually complete in children, but recovery is slower and more frequently incomplete in adults. When remission has been achieved, yearly follow-up is recommended for adults, children, and adolescents. This article deals with conventional strategies used in order to follow-up patients on treatment and aiming to obtain the best clinical outcome.

Galectins in Intestinal Inflammation: Galectin-1 Expression Delineates Response to Treatment in Celiac Disease Patients

Galectins, a family of animal lectins characterized by their affinity for N-acetyllactosamine-enriched glycoconjugates, modulate several immune cell processes shaping the course of innate and adaptive immune responses. Through interaction with a wide range of glycosylated receptors bearing complex branched N-glycans and core 2-O-glycans, these endogenous lectins trigger distinct signaling programs thereby controling immune cell activation, differentiation, recruitment and survival. Given the unique features of mucosal inflammation and the differential expression of galectins throughout the gastrointestinal tract, we discuss here key findings on the role of galectins in intestinal inflammation, particularly Crohn’s disease, ulcerative colitis, and celiac disease (CeD) patients, as well as in murine models resembling these inflammatory conditions. In addition, we present new data highlighting the regulated expression of galectin-1 (Gal-1), a proto-type member of the galectin family, during intestinal inflammation in untreated and treated CeD patients. Our results unveil a substantial upregulation of Gal-1 accompanying the anti-inflammatory and tolerogenic response associated with gluten-free diet in CeD patients, suggesting a major role of this lectin in favoring resolution of inflammation and restoration of mucosal homeostasis. Thus, a coordinated network of galectins and their glycosylated ligands, exerting either anti-inflammatory or proinflammatory responses, may influence the interplay between intestinal epithelial cells and the highly specialized gut immune system in physiologic and pathologic settings.

Creation of a model to predict survival in patients with refractory coeliac disease using a multinational registry

BACKGROUND

Refractory coeliac disease is a severe complication of coeliac disease with heterogeneous outcome.

AIM

To create a prognostic model to estimate survival of patients with refractory coeliac disease.

METHODS

We evaluated predictors of 5-year mortality using Cox proportional hazards regression on subjects from a multinational registry. Bootstrap resampling was used to internally validate the individual factors and overall model performance. The mean of the estimated regression coefficients from 400 bootstrap models was used to derive a risk score for 5-year mortality.

RESULTS

The multinational cohort was composed of 232 patients diagnosed with refractory coeliac disease across seven centres (range of 11-63 cases per centre). The median age was 53 years and 150 (64%) were women. A total of 51 subjects died during a 5-year follow-up (cumulative 5-year all-cause mortality = 30%). From a multiple variable Cox proportional hazards model, the following variables were significantly associated with 5-year mortality: age at refractory coeliac disease diagnosis (per 20 year increase, hazard ratio = 2.21; 95% confidence interval, CI: 1.38-3.55), abnormal intraepithelial lymphocytes (hazard ratio = 2.85; 95% CI: 1.22-6.62), and albumin (per 0.5 unit increase, hazard ratio = 0.72; 95% CI: 0.61-0.85). A simple weighted three-factor risk score was created to estimate 5-year survival.

CONCLUSIONS

Using data from a multinational registry and previously reported risk factors, we create a prognostic model to predict 5-year mortality among patients with refractory coeliac disease. This new model may help clinicians to guide treatment and follow-up.

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.

Psychological morbidity of celiac disease: A review of the literature

BACKGROUND

Celiac disease has been linked to decreased quality of life and certain mood disorders. The effect of the gluten free diet on these psychological aspects of the disease is still unclear.

OBJECTIVES

The objective of this article is to review the literature on psychological morbidity of celiac disease.

METHODS

We performed a PubMed search for the time period from 1900 until June 1, 2014, to identify papers on psychological aspects of celiac disease looking specifically at quality of life, anxiety, depression and fatigue.

RESULTS

Anxiety, depression and fatigue are common complaints in patients with untreated celiac disease and contribute to lower quality of life. While aspects of these conditions may improve within a few months after starting a gluten-free diet, some patients continue to suffer from significant psychological morbidity. Psychological symptoms may affect the quality of life and the dietary adherence.

CONCLUSION

Health care professionals need to be aware of the ongoing psychological burden of celiac disease in order to support patients with this disease.

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.

Issues associated with the emergence of coeliac disease in the Asia–Pacific 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 Asia–Pacific 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 Asia–Pacific region, Europe, North America, and South America reviewed relevant existing literature with focus on those issues specific to Asia–Pacific 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 Asian–Pacific 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 Asia–Pacific region define extent of problem and get prepared to handle impending epidemic of CD.

IL-15 controls T cell functions through its influence on CD30 and OX40 antigens in Celiac Disease

AIM

To evaluate the ability of interleukin (IL)-15 to control T cell functions through its influence on CD30 and OX40 expressing cells in Celiac Disease (CD). In peripheral blood (PB), by examining the expression of OX40 in conventional effectors cells and T cells with a phenotypic specialization of regulatory cells [CD4+CD25high forkhead box protein 3 (Foxp3)+], and the co stimulation of IFN-γ and IL-4 production within CD30 and OX40 positive subsets of T cells. At the duodenal mucosa, by assessing the expression of CD30 and OX40 in intraepithelial (IE) and lamina propria (LP) lymphocytes (IEL, LPL).

PATIENTS AND METHODS

PB and duodenal mucosal biopsies were obtained from 38 patients with classic CD (Cel) and 38 healthy controls (HC). Analysis of cell surface and/or intracellular antigens was performed in anti-CD3-treated PB mononuclear cells (PBMC) before and after treatment with recombinant IL-15 (rIL-15), and in IE and LP cellular suspensions prepared from duodenal biopsies pre-treated with/without rIL-15.

RESULTS

A subpopulation of CD3+OX40+ T blasts was induced in Cel and HC by a 3days treatment of PBMC with anti-CD3 and decreased its size thereafter, regardless of the presence of rIL-15. However, the addition of rIL-15 to T blasts distinctively induced the survival of T cells with a regulatory phenotype that expresses OX40 antigen in Cel (p<0.05). Celiac patients showed higher frequencies of IFN-γ-producing CD3+CD30+ blasts before and after treatment with rIL-15 (p<0.05, vs. HC). IL-15 increased the frequencies of CD3+CD30+ LPL (HC: p<0.05, Cel: p<0.05) but not of CD3+OX40+ LPL, and CD30 or OX40 positive IEL.

CONCLUSIONS

The distinctive control of OX40+ cells with a T regulatory phenotype mediated by the influence of IL-15 comes out as new function of this cytokine in the context of CD. The higher production of IFN-γ by a subpopulation of peripheral CD3+CD30+ cells contributes to the type I biased immune response.

Non-Celiac Gluten sensitivity: the new frontier of gluten related disorders

Non Celiac Gluten sensitivity (NCGS) was originally described in the 1980s and recently a “re-discovered” disorder characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food, in subjects that are not affected with either celiac disease (CD) or wheat allergy (WA). Although NCGS frequency is still unclear, epidemiological data have been generated that can help establishing the magnitude of the problem. Clinical studies further defined the identity of NCGS and its implications in human disease. An overlap between the irritable bowel syndrome (IBS) and NCGS has been detected, requiring even more stringent diagnostic criteria. Several studies suggested a relationship between NCGS and neuropsychiatric disorders, particularly autism and schizophrenia. The first case reports of NCGS in children have been described. Lack of biomarkers is still a major limitation of clinical studies, making it difficult to differentiate NCGS from other gluten related disorders. Recent studies raised the possibility that, beside gluten, wheat amylase-trypsin inhibitors and low-fermentable, poorly-absorbed, short-chain carbohydrates can contribute to symptoms (at least those related to IBS) experienced by NCGS patients. In this paper we report the major advances and current trends on NCGS.

Diagnosis of celiac disease during pre-operative work-up for bariatric surgery

BACKGROUND AND AIM

Morbid obesity is a highly prevalent condition. In selected cases, bariatric surgery is indicated. Although for decades celiac disease (CD) has been associated with chronic diarrhea and weight loss, now it becomes clear that the clinical spectrum is extremely wide.

METHODS

We report 5 morbidly obese patients that were diagnosed of CD during preoperative work-up for bariatric surgery. Diagnosis was suspected during routine upper endoscopy, and confirmed by histology and positive CD-specific serology.

RESULT

Four of the 5 cases were asymptomatic. One complained of chronic diarrhea and anemia. All cases initiated a gluten-free diet. Due to CD, patients were offered a purely restrictive bariatric procedure. Three patients underwent a sleeve gastrectomy while the other two are still undergoing pre-operative evaluations.

CONCLUSION

This report enlarges the clinical spectrum of untreated CD. Although prevalence of CD in obese patients seems to be similar to that in the general population, morbid obese patients should be tested for CD in order to establish the best surgical strategy and outcome.

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.

Celiac disease serology in patients with different pretest probabilities: Is biopsy avoidable?

AIM: To establish the diagnostic performance of several serological tests, individually and in combination, for diagnosing celiac disease (CD) in patients with different pretest probabilities, and to explore potential serological algorithms to reduce the necessity for biopsy.

METHODS: We prospectively performed duodenal biopsy and serology in 679 adults who had either high risk (n = 161) or low risk (n = 518) for CD. Blood samples were tested using six assays (enzyme-linked immunosorbent assay) that detected antibodies to tissue transglutaminase (tTG) and deamidated gliadin peptide (DGP).

RESULTS: CD prevalence was 39.1% in the high-risk population and 3.3% in the low-risk group. In high-risk patients, all individual assays had a high diagnostic efficacy [area under receiving operator characteristic curves (AU ROC): 0.968 to 0.999]. In contrast, assays had a lower diagnostic efficacy (AU ROC: 0.835 to 0.972) in the low-risk group. Using assay combinations, it would be possible to reach or rule out diagnosis of CD without biopsy in 92% of cases in both pretest populations. We observed that the new DGP/tTG Screen assay resulted in a surplus compared to more conventional assays in any clinical situation.

CONCLUSION: The DGP/tTG Screen assay could be considered as the best initial test for CD. Combinations of two tests, including a DGP/tTG Screen, might be able to diagnose CD accurately in different clinical scenarios making biopsy avoidable in a high proportion of subjects.

New Serology Assays Can Detect Gluten Sensitivity among Enteropathy Patients Seronegative for Anti–Tissue Transglutaminase

Background: Some patients with celiac disease (CD) may be seronegative with the commonly used test for IgA anti–tissue transglutaminase (anti-tTG) antibodies. Our aim was to explore whether newer assays incorporating synthetic deamidated gliadin-related peptides (DGPs) or other TG isoenzymes as antigen are useful for detecting gluten sensitivity in IgA anti-tTG–seronegative patients.

Methods: We assayed serum samples obtained at diagnosis from (a) anti-tTG–seronegative patients with a CD-like enteropathy (n = 12), (b) skin biopsy–proven dermatitis herpetiformis (DH) patients (n = 26), and (c) IgA anti-tTG–positive CD patients (n = 26). All patients had typical total IgA concentrations. All patients underwent intestinal biopsy and serum testing for (a) detection of IgA and IgG isotypes of both anti-DGP and anti-tTG in a single assay (tTG/DGP Screen; INOVA Diagnostics), (b) simultaneous detection of both IgA and IgG anti-DGP antibody isotypes (DGP Dual; INOVA Diagnostics), and (c) detection of antibodies to transglutaminase 3 (TG3) or transglutaminase 6 (TG6).

Results: All anti-tTG–seropositive patients also tested positive in anti-DGP assays. Overall, tTG/DGP Screen detected 6 (31.6%) of the 19 anti-tTG seronegatives, and anti-DGP Dual produced positive results in 5 (26.3%) of these cases. Whereas both assays detected 2 anti-tTG–negative DH patients with partial villous atrophy, they were positive in only 2 of the 5 cases with no histologically discernible mucosal damage. Testing for antibodies to TG3 and TG6 identified 7 (36.8%) of the 19 anti-tTG–negative patients, 5 of which were also positive for anti-DGP.

Conclusions: Detection of anti-DGP with tTG/DGP Screen or anti-DGP Dual, or detection of antibodies to other TG isoenzymes, enhances the sensitivity for detecting gluten sensitivity among non–IgA- deficient, anti-tTG–seronegative patients with CD-like enteropathy.

Low-dose aspirin affects the small bowel mucosa: results of a pilot study with a multidimensional assessment

BACKGROUND & AIMS

Whether low-dose aspirin (acetylsalicylic acid [ASA]) produces intestinal damage is controversial. Our aim was to determine whether the small bowel is damaged by low-dose ASA on a short-term basis.

METHODS

Twenty healthy volunteers (age range, 19-64 years) underwent video capsule endoscopy (VCE), fecal calprotectin, and permeability tests (sucrose and lactulose/mannitol [lac/man] ratio) before and after ingestion of 100 mg of enteric-coated ASA daily for 14 days. Video capsule images were assessed by 2 independent expert endoscopists, fully blinded to the treatment group, by using an endoscopic scale.

RESULTS

Post-ASA VCE detected 10 cases (50%) with mucosal damage not apparent in baseline studies (6 cases had petechiae, 3 had erosions, and 1 had bleeding stigmata in 2 ulcers). The median baseline lac/man ratio (0.021; range, 0.011-0.045) increased after ASA use (0.036; range, 0.007-0.258; P = .08), and the post-ASA lac/man ratio was above the upper end of normal (>0.025) in 10 of 20 volunteers (vs baseline, P < .02). The median baseline fecal calprotectin concentration (6.05 microg/g; range, 1.9-79.2) also increased significantly after ASA use (23.9 microg/g; range, 3.1-75.3; P < .0005), with 3 patients having values above the cutoff (>50 microg/g). Five of 10 subjects with abnormal findings at VCE also had lac/man ratios above the cutoff. Median baseline sucrose urinary excretion (70.0 mg; range, 11.8-151.3) increased significantly after ASA administration (107.0 mg; range, 22.9-411.3; P < .05).

CONCLUSIONS

The short-term administration of low-dose ASA is associated with mucosal abnormalities of the small bowel mucosa, which might have implications in clinical practice.

[Why are there few publications by the Argentine gastroenterology? Considerations on a bibliometric analysis of Argentine publications on gastroenterology]

The publication of scientific findings is the main way to communicate advances. Our aim was to perform a bibliometric and comparative analysis of the Argentinean gastroenterological research output. We analyzed Argentinean gastroenterological publications selectively retrieved from LILACS (between years 1982-2006) and EMBASE (1996-2007) databases by means of specially constructed filter based on author address and subject headings. The global Argentinean scientific research output is far below that of developed countries and has been affected in direct manner by economic, political and social disturbances in the country. The gastroenterological research output from Argentina represent about 6% of national biomedical research. While 54% belongs to gastroenterology and 46% to hepatology, 65% are based on clinical research and 67% were originally contributions. Only 11% have been published in high impact factor journals. The comparative analysis within countries with health indicators similarities has shown a low biomedical and gastroenterology research output, however, the rate of acceptance at the 18 top gastroenterological journals is acceptable (15%). The contributions of registered specialists were lower for gastroenterologists compared with those from hepatologists (8.7% and 16.4% respectively). The research projects at public hospital funded by the pharmaceutical industry overcome those funded independently. Indeed, it seems that the independent research is being progressively replaced by that supported by the industry due to economic benefits for researchers even when there is a very low participation rate in publications (3%) by Argentinean researchers. We conclude that the Argentinean biomedical and gastroenterological research output is scanty compared with developed countries and countries with comparable health indicators. Our analysis suggests that efforts must be taken to attain objectives directed to develop and improve the Argentinean biomedical and gastroenterological scientific work and publication.

A prospective evaluation of endoscopic markers for identifying celiac disease in patients with high and low probability of having the disease

BACKGROUND/OBJECTIVES

the usefulness of duodenoscopic markers for predicting celiac disease (CD) has been questioned. We assessed the diagnostic efficacy of endoscopic markers of mucosal atrophy in individuals with different pretest probability of CD.

METHODS

we prospectively performed endoscopic intestinal biopsies and CD-related serology tests in 661 individuals, including 143 consecutive patients attending a malabsorption clinic (high pretest probability) and 518 subjects randomly selected fom those undergoing routine endoscopy because of upper GI symptoms (low pretest probability). Duodenoscopic markers reported were: mosaic pattern, scalloped folds, and reduction in number or loss of Kerkring's folds.

RESULTS

sixty-three (44.1%) and 18 (3.5%) patients were diagnosed with CD in the high and low risk groups, respectively Among high pretest subjects, the presence of any marker had very high sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for the identification of CD (92.1%, 93.8%, 92.1%, 93.8% and 93.0%, respectively). The performance of these parameters for the presence of any marker in the low pretest population were 61.1%, 96.8%, 40.7%, 98.6% and 95.6%, respectively. Sensitivity (p < 0.004) and positive predictive value (p < 0.0001) of markers were significantly higher for the high risk patients. The identification of a reduction in number or loss of Kerkring'sfolds was not a reliable finding unless other signs were also present.

CONCLUSIONS

we confirm that endoscopic markers are useful in predicting CD in different clinical scenarios. The high negative predictive value in the low probability group suggests that intestinal biopsy is not required if endoscopic markers are absent.

Systematic review and meta-analysis of observational studies on the prevalence of fractures in coeliac disease

BACKGROUND/AIMS

Evidence of an increased bone fracture risk in coeliac disease is on debate. Our aim was to review systematically the current published information on fractures in coeliac disease and to perform a meta-analysis.

METHODS

Case-control and cohort designs were identified by searching MEDLINE (1966-April 2007) and LILACS (1982-April 2007). Participants were adult coeliac disease patients of any sex and the outcome measure was the presence of any fracture. Studies were screened for inclusion by two authors who independently extracted the data. Methodological quality was assessed using the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology Statement) recommendations. Data were analysed using the RevMan Analyses statistical package in Review Manager (version 4.2.8) and reported as pooled odds ratio using a random effect model. Heterogeneity was investigated (standard chi(2) test) and sensitivity analysis was performed based on the reported quality and design type.

RESULTS

While 60 of 405 studies met the initial screening criteria, only 8 met inclusion criteria after detailed review. These studies evaluated a total of 20,955 coeliac disease patients having 1819 (8.7%) fractures and 96,777 controls with 5955 (6.1%) fractures (pooled odds ratio=1.43; 95% confidence interval 1.15-1.78) with considerable heterogeneity among studies (p<0.00001).

CONCLUSIONS

Our meta-analysis confirms a significant association between bone fractures and coeliac disease. However, qualitative and quantitative differences among studies were evident. Further research is necessary to investigate the relevance of this heterogeneity.

Antibodies against synthetic deamidated gliadin peptides as predictors of celiac disease: prospective assessment in an adult population with a high pretest probability of disease

BACKGROUND

Noninvasive serologic tests have shown high diagnostic accuracy for celiac disease (CD) in selected populations. Our aim was to determine prospectively the performance of CD-related serology in individuals undergoing intestinal biopsy because of clinical suspicion of small-bowel disorders.

METHODS

We enrolled 141 unselected consecutive adult patients attending a small-bowel disease clinic. Patients underwent endoscopy and biopsy; serum samples were obtained at that time for measurements of anti-tissue transglutaminase (a-tTG), IgA and IgG anti-deamidated gliadin-related peptide (a-DGP), and IgA antiactin antibodies (AAAs). Characterization of patients was based on histological criteria (Marsh type II lesion or greater).

RESULTS

The prevalence of CD was 42.5%. Sensitivity, specificity, and positive and negative predictive values were >90% for most assays. Diagnostic accuracy based on ROC curve analysis was similar for all assays [area under the curve (95% CI): 0.996 (0.967-0.998) for a-tTG, 0.995 (0.964-0.998) for IgA a-DGP, 0.989 (0.954-0.999) for IgG a-DGP, 0.996 (0.966-0.998) for blended conjugated of IgA + IgG a-DGP in a single assay, and 0.967 (0.922-0.990) for AAA]. The combinations of 2 tests, IgG a-DGP plus IgA a-tTG or the single blended conjugate detecting IgA + IgG a-DGP plus IgA a-tTG had 100% positive and negative predictive values if concentrations of both tests in either combination were above or below the cutoff.

CONCLUSIONS

In a population with high pretest probability, the newly developed a-DGP tests have diagnostic accuracy that is at least equivalent to that of established assays.

Clinical utility of counting intraepithelial lymphocytes in celiac disease intestinal mucosa

BACKGROUND/AIMS

Our aims were to establish the clinical utility of assessing the intraepithelial lymphocyte (IEL) density in intestinal biopsies from a large series of individuals and to determine the best threshold discriminating celiac disease (CD) patients and controls in two populations with different pre-test prevalence.

METHODS

We prospectively performed intestinal biopsy and CD-related serology in 349 subjects undergoing upper GI endoscopy. While 116 had symptoms suggestive of a small bowel disorder (high prevalence), 233 individuals were randomly selected from patients referred to endoscopy because upper GIsymptoms (low prevalence). Diagnosis of CD was based on the concordance of classical histological features and a positive CD serology.

RESULTS

While 58 patients had a newly diagnosed CD (52 in the high and 6 in the low prevalence groups), 291 subjects did not meet diagnostic criteria of the disorder. Patients had a highly significant greater IEL density than controls (p < 0.00001). Based on the ROC curve, a count of 22.8 IEL/100 epithelial cells had the highest performance for diagnosing CD in the overall population and for subjects in the high pre-test probability subgroup and 22.5% was ,he best cut-off for those diagnosed in the low risk population (area under the curves: 0.979, 0.979 and 0.993, respectively). An abnormal CD serology confirmed the diagnosis of CD in all the four patients with counts below 22.8%.

CONCLUSIONS

Our study confirms that an IEL density of 22.8% is an adequate threshold to discriminate CD patients and controls in individuals irrespective of the prevalence of the disorder.

Celiac disease serology in dermatitis herpetiformis. Which is the best option for detecting gluten sensitivity?

BACKGROUND

Dermatitis herpetiformis (DH), a well-established gluten-sensitive skin disorder presenting variable degrees of enteropathy, constitutes a very useful model in order to assess the utility of the celiac disease (CD)-related serology in patients with mild intestinal damage.

OBJECTIVE

Our aim was to explore comparatively the performance of a panel of CD-related serologic tests in patients with DH.

METHODS

We assessed a series of 18 consecutive patients with skin biopsy proven DH presenting the overall spectrum of intestinal damage ranging from normal mucosa (n = 6) to total villous atrophy (TVA) (n = 6) through partial villous atrophy (PVA) (n = 6). Sera were obtained from all patients while consuming a gluten containing diet. Serologic tests were antiendomysial, anti-tissue transglutaminase and antigliadin antibodies, and newly developed tests detecting both antibody isotypes (IgA and IgG) against deamidated synthetic gliadin-derived peptides (a-GDP).

RESULTS

Serologic tests had a variable behaviour depending on the degree of enteropathy. While the majority of tests detected patients with TVA, only 50% of those with normal histology had positive assays. Patients with PVA had discordant results. Classical CD-specific tests were positive in only some patients with mild damage while all of them were identifed by a single assay detecting both isotypes of a-GDR CONCLUSION: The detection of a-GDP antibodies was the most reliable tool in order to identify gluten sensitivity in DH patients presenting a wide range of intestinal damage. Further studies should explore if these findings can be extrapolated to patients with CD having mild enteropathy.

Accuracy of testing for antibodies to synthetic gliadin-related peptides in celiac disease

BACKGROUND & AIMS

Our aim was to explore the diagnostic value of a newly developed synthetic peptide antibody assay addressing specific synthetic gliadin-derived deamidated peptides (AGA II) for the diagnosis of celiac disease (CD).

METHODS

We assayed serum samples obtained prospectively at diagnosis from a population of 92 consecutive adult patients with CD and 113 non-CD controls. Patients were reevaluated after 6 months (n = 56) and 1 year (n = 20) of treatment. All patients and controls underwent intestinal biopsy and a set of CD-related serology tests. A newly developed enzyme-linked immunosorbent assay (ELISA) for detecting IgA and IgG antibodies against synthetic deamidated gliadin epitopes was used.

RESULTS

At diagnosis, sensitivity and specificity were 94.6% and 99.1% for AGA II IgA and 92.4% and 100% for AGA II IgG. Absolute values and the proportion of positive samples for both antibodies were significantly reduced at 6 months (P < .0000) and 1 year (P < .001) after initiation of a gluten-free diet. Compared with conventional AGA, the peptide antibodies had greater sensitivity, specificity, positive and negative predictive values, accuracy, and likelihood ratios. Compared with antitissue transglutaminase antibodies, AGA II had similar sensitivity but greater specificity and predictive values, better likelihood ratios, and an excellent agreement (kappa statistic = .92).

CONCLUSIONS

This study assessed the value of an ELISA assay in detecting antibodies to gliadin-related peptides. This assay appears to be a reliable tool for diagnosing CD and suggests promising accuracy that may be very useful in clinical practice.

Decision analysis: an aid to the diagnosis of Whipple's disease

BACKGROUND

Diagnosis of Whipple's disease, a rare systemic infection affecting predominantly the small bowel, is based on the identification of the bacterium Tropheryma whipplei.

AIMS

To make explicit diagnostic uncertainties in Whipple's disease through a decision analysis, considering two different clinical scenarios at presentation.

METHODS

Using appropriate software, a decision tree estimated the consequences after testing different strategies for diagnosis of Whipple's disease. Probabilities and outcomes to determine the optimum expected value were based on MEDLINE search.

RESULTS

In patients with clinically-predominant intestinal involvement, diagnostic strategies considering intestinal biopsy for histology (including appropriate staining) and the polymerase chain reaction testing for bacterial DNA were similarly effective. In case of failure of one procedure, the best sequential choice was a polymerase chain reaction analysis after a negative histology. Of the five strategies tested for cases with predominant focal neurological involvement, the stereotaxis cerebral biopsy evidenced the highest expected value. However, using quality-adjusted life-years considering the morbidity of methods, intestinal biopsy for PCR determination was the best choice.

CONCLUSIONS

In patients with Whipple's disease having predominant digestive involvement, intestinal biopsies for histology should be indicated first and, if negative, a bacterial polymerase chain reaction determination should be the next option. Although the molecular polymerase chain reaction assessment of cerebral biopsies has the highest diagnostic yield in neurological Whipple's disease, its associated morbidity means that analyses of intestinal samples are more appropriate.

The IL-1 gene family and bone involvement in celiac disease

Celiac disease (CD) is associated with decreased bone mineral mass. Its pathogenesis is multifactorial since both systemic and local mechanisms may play a role. Our objective was to determine whether single-nucleotide polymorphisms in genes encoding members of the interleukin-1 family are associated with bone damage measured by densitometry in a series of 71 adult CD patients assessed at diagnosis. When compared with non-carrier CD patients, carriers of allele T of the interleukin-1beta gene (IL1B-511T) had a significantly lower bone mass at the total skeleton level (p = 0.0484) and a greater prevalence of osteopenia/osteoporosis (p = 0.0102). To our knowledge, this is the first evidence on the association between a genetic predisposition and low bone mass in CD patients. This finding supports the postulated inflammation-associated bone loss pathogenesis as one of the causes of bone weakness in CD.

Bones in coeliac disease: diagnosis and treatment

Coeliac disease predisposes to metabolic osteopathy. The entity of bone loss is higher in patients with malabsorption at diagnosis but it is also present in asymptomatic or poorly symptomatic patients, occurring in roughly half of them. Calcium malabsorption and the release of proinflammatory cytokines, activating osteoclasts, represent the main mechanisms responsible for bone derangement. In coeliacs, the presence of an increased fracture risk was recently questioned and its importance on clinical grounds was reconsidered, in view of the fact that gluten-free diet generally improves bone mass and, consequently, reduces fracture risk. However, gluten-free diet rarely normalizes bone mass and the co-administration of mineral active drugs may be useful in a subgroup of coeliacs.

Significance of smooth muscle/anti-actin autoantibodies in celiac disease

BACKGROUND/AIM

Smooth muscle antibody (SMA) specific for the protein actin, a major component of the cytoskeleton of epithelial cells, is one of the most prevalent non-organ specific autoantibodies in the serum of celiac disease (CD) patients. Our aim was to explore the clinical relevance of the presence of IgA type anti-actin antibody (AAA) and SMA in a series of patients with CD.

METHODS

We evaluated frozen serum samples collected at diagnosis from 92 adult patients with CD and 52 control individuals in whom CD was excluded. Patients were re-evaluated a median time of 5 yr after treatment. IgA type AAA was detected using a modified commercial ELISA assay and IgA SMA was detected using indirect immunofluorescence on primate esophagus substrate.

RESULTS

At diagnosis, samples from CD patients had significantly higher AAA values than controls (p<0.00001). While all active CD patients had serum AAA values over the cut-off for healthy controls, we observed a very significant reduction of these antibodies after treatment (p>0.0001). AAA had a highly significant correlation with both, tissue, transglutaminase (r=0.62) and antigliadin (r=0.60, p<0.00001) antibodies as well as the severity of the intestinal injury (p<0.05). SMA was detected in sera of 35 consecutive CD patients. At diagnosis, SMA positive patients had significantly higher values of AAA (p<0.0002), increased number of autoimmune disorders (p<0.04), delayed menarche (p<0.04), lower hemoglobin levels (p<0.01), increased fecal a-I antitrypsin clearance (p<0.01) and more severe diarrhea (p<0.06). We also detected a trend to more severe complications at follow-up (p=0.059).

CONCLUSIONS

Based on our findings we suggest that the presence of increased IgA AAA serum levels is a highly sensitive marker of the disturbed architecture of intestinal epithelial cells of CD patients with a potential relevance to diagnosis and follow-up. The presence of SMA seems to define a distinct subset of CD patients with a more severe clinical outcome.

[Activity index in Crohn's disease]

The gold standard to quantify Crohn's disease activity is still not defined and a world consensus to unify criteria is necessary. Criticism has been directed towards every existing indexes. We summarize some of the currently used criteria for the assessment of disease activity, point out the controversies and issues that will need further investigations, and discuss their usefulness based on our experience.

Whipple's disease

Whipple's disease is a rare multisystemic infectious disorder affecting predominantly middle-aged men. Clinical manifestations are very variable with a very long, insidious, prediagnostic course. Weight loss, chronic diarrhea, arthralgias, and low-grade fever are characteristic features in most patients. Although gastrointestinal compromise is very common, atypical clinical forms are being increasingly recognized. Although a bacterial cause was strongly suggested for many years, the infectious agent was elusive until recently. The bacillus that was classified as an actinomycete was named Tropheryma whipplei and has singular characteristics. It presents affinity for the periodic acid-Schiff stain, but it is negative for Ziehl-Neelsen staining and has a characteristic trilamellar cell wall. Its genetic material has been recently sequenced, and culture was finally performed on a human fibroblast cell line. Pathological specimens show macrophage infiltration with mostly intracellular invasion of live bacteria. Immunologic factors, such as a subtle defect of cellular immunity possibly specific for the Whipple's bacterium, are believed to play a role in pathogenesis. The diagnosis requires the histologic assessment of diseased tissue, showing the characteristic infiltration, as a first approach, and confirmatory tests such as electron microscopy and/or polymerase chain reaction. Antibiotic treatment is mandatory and leads to a rapid clinical improvement and remission in most patients. Although the rationale for treatment is largely empiric, current recommendations include a 2-week parenteral therapy (third generation cephalosporin) followed by a long-term therapy with trimethoprim-sulphamethoxazole. This approach has been shown to reduce the number of relapses and was effective for prevention and/or treatment of the neurologic compromise.

Stratification of bone fracture risk in patients with celiac disease

BACKGROUND AND AIMS

Our objective in this cross-sectional, case-control study was to gain insight into celiac osteopathy by examining a well-defined cohort of patients with a wide clinical spectrum of the disease.

METHODS

We studied 148 unselected celiac patients and 296 (1:2) age- and sex-matched controls diagnosed with functional gastrointestinal disorders. Based on the clinical history, 53% were classically symptomatic, 36% had subclinical celiac disease, and 11% were silent, detected by screening. The fracture information was obtained through an in-person interview using a pre-designed questionnaire.

RESULTS

Classically symptomatic patients had an increased number of fractures in the peripheral skeleton (47%) compared with age- and sex-matched controls (15%; odds ratio, 5.2; 95% confidence interval, 2.8-9.8). However, fractures in subclinical/silent celiac cases (20%) were no different from those in controls (14%; odds ratio, 1.7, 0.7-4.4). Compared with the subclinical/silent group, a significantly greater prevalence of fractures was detected in classically symptomatic patients (odds ratio, 3.6, 1.7-7.5). Compared with controls, celiac disease patients had significantly more fractures produced by mild trauma (P < 0.01), but there were no differences in the severity of trauma events that induced fractures. Mean bone density femoral neck z score was higher for subclinical/silent cases compared with classically symptomatic patients (P < 0.05).

CONCLUSIONS

Celiac patients show a very wide variation in fracture risk, with increased risk in classically symptomatic patients. Diagnostic and therapeutic strategies to prevent bone loss and fracture should be preferentially used in the subgroup of patients with classic clinical disease.

Antibodies to human recombinant tissue transglutaminase may detect coeliac disease patients undiagnosed by endomysial antibodies

BACKGROUND

The screening and diagnosis of coeliac disease have been simplified by the advent of new serological tools.

AIM

To assess the clinical utility of a newly developed kit for antibodies to human recombinant tissue transglutaminase (hu-anti-tTG) in a large population of patients undergoing intestinal biopsy for suspected intestinal disorders.

METHODS

We evaluated 426 serum samples from consecutive adult patients (250 from untreated coeliac disease patients and 176 from individuals in whom a diagnosis of coeliac disease had been excluded), obtained at the time of intestinal biopsy. Samples were tested for immunoglobulin A (IgA) hu-anti-tTG by enzyme-linked immunoabsorbent assay, IgA endomysial antibodies (EmA) by indirect immunofluorescence and IgA and IgG antigliadin antibodies by enzyme-linked immunoabsorbent assay. A sub-group of samples was also assessed for a guinea-pig-based anti-tissue transglutaminase.

RESULTS

According to the cut-off for hu-anti-tTG, the sensitivity, specificity and positive and negative predictive values were 91%, 96%, 97% and 87%, respectively. Simultaneous determination of EmA showed values of 86%, 100%, 100% and 83% for the same parameters. Although 19 coeliac disease patients (7.6%) were negative for EmA and hu-anti-tTG, both tests rendered superior statistical values to antigliadin antibody tests. At diagnosis, IgA deficiency was detected in 11 patients, but both assays were able to detect samples with mild to moderate deficiency. The comparison of hu-anti-tTG with EmA showed excellent concordance between the tests (kappa statistic, 0.85). Discordance was observed in 20 samples from coeliac disease patients (8%) and in nine samples from controls (5%). Fifteen samples had an EmA-negative but hu-anti-tTG-positive serology, and five showed the converse pattern. Comparison of human recombinant and guinea-pig tests showed concordant results in 96% of cases.

CONCLUSIONS

The quantitative determination of hu-anti-tTG type IgA using a commercial enzyme-linked immunoabsorbent assay kit was highly sensitive and specific for the detection of coeliac disease. Our results in a large population of patients with a clinical condition suggestive of the disorder demonstrated that the test can be used to detect a substantial number of patients otherwise unrecognized by IgA EmA.

Analysis of the structure and strength of bones in celiac disease patients

OBJECTIVE

The aim of this study was to gain insight into the pathogenesis of bone mass loss and weakening affecting patients with celiac disease, according to the new concepts of bone structure/strength and muscle/bone interrelationships.

METHODS

We studied serum variables and tomographic indicators of bone structure and strength and regional muscle masses in a series of patients at diagnosis and after 1 yr on a gluten-free diet and in gender- and age-matched controls.

RESULTS

At diagnosis, serum levels of calcium and vitamin D were low, and indicators of parathyroid hormone activity and bone formation and resorption were increased. All these parameters were normalized by treatment. Peripheral quantitative CT scans of the distal radius revealed that cortical bone was generally more affected than trabecular bone. The cross-sectional area (CSA) and the volumetric mineral content and density of cortical bone (indicators of cortical tissue mass and mechanical quality), and moments of inertia (CSMI, indicator of the bone architectural design) were in the lower end of normal range in men, and below that in 50% of women. In men, the CSMI/CSA ratio (indicator of the architectural efficiency of distribution of the available cortical tissue) was lower than expected and remained unchanged after treatment. In women, the baseline ratio was normal, but both the ratio and the CSMI were low at diagnosis and normalized after treatment. Both baseline values and the treatment-induced changes of cortical and trabecular bone in the radius and the axis (L3) correlated inversely with serum parathyroid hormone levels. Baseline values or changes in the mineral content of the vertebral bone correlated with the CSA of psoas and spine-extensor muscles. Multiple regression analyses showed that metabolic and mechanical parameters were independent determinants of different aspects of the vertebral bone weakening.

CONCLUSIONS

Our results show that bone weakening in celiac disease might result from both 1) a metabolic disturbances of bone remodeling affecting trabecular and cortical bone masses and the mechanical quality of the bone material, and 2) a reduction of muscle strength impairing the modeling-dependent optimization of bone architectural design and mass of cortical bone. Dietary treatment seems to correct almost exclusively the metabolically induced disturbances, which were predominant in women.

Azathioprine in refractory sprue: results from a prospective, open-label study

OBJECTIVE

Refractory sprue is a rare and severe malabsorptive disorder that mimics celiac disease but is refractory to a gluten-free diet and is without initial evidence of overt lymphoma. Treatment is largely empiric and often ineffective, with steroids and immunosuppression being the mainstream therapeutic options. The aim of this study was to evaluate prospectively the effect of azathioprine on a group of patients diagnosed with refractory sprue.

METHODS

We studied seven consecutive patients (five women and two men) with a well-defined diagnosis of refractory sprue and a lack of response to oral or parenteral steroids. At diagnosis, five patients had endoscopic evidence of ulcerative jejunitis, and five underwent exploratory laparotomy for exclusion of malignancies. The characteristic monoclonal TCRgamma gene rearrangement was shown in five of six patients studied. Patients were treated for a mean of 11 months (range 8-12 months), and clinical, biochemical, molecular, and histological parameters were reassessed at the end of the trial. The study was a prospective, open-label, non-placebo-controlled study using azathioprine (2 mg/kg/ day) plus oral prednisone (1 mg/kg/day). A gluten-free diet (n = 7) as well as enteral (n = 6) and parenteral nutrition (n = 5) were administered during the trial.

RESULTS

After treatment, five patients had a complete clinical remission, and biochemical and nutritional parameters were significantly improved. Steroids were tapered after the onset of azathioprine, and no patient was on steroids at the end of the trial. Intestinal histology improved significantly in all cases (normal histology in three cases and minor infiltration in the lamina propria in two). Two patients did not respond to treatment at any time and died in months 10 and 9, of an irreversible ventricular fibrillation and sepsis, respectively. No overt lymphoma was demonstrated during the follow-up.

CONCLUSIONS

The present study confirms earlier anecdotal reports on the efficacy of azathioprine in refractory sprue, with clear clinical and histological improvement shown in most patients. However, monoclonality persisted after treatment. We consider that a larger number of patients should be evaluated before a definitive recommendation is adopted for use of this drug in refractory sprue.

Bone-specific antibodies in sera from patients with celiac disease: characterization and implications in osteoporosis

Osteopenia and osteoporosis are well-known complications detected in celiac disease patients with still obscure pathogenesis. In the present study we investigated the presence of circulating anti-bone autoantibodies in patients with celiac disease and explored their role in the associated bone disease. We evaluated serum samples from 33 patients at the time of diagnosis and from 20 of them after treatment. Sera from patients with inflammatory bowel disease (n = 9), nonceliac osteoporotic (n = 18), and healthy individuals (n = 10) were used as controls. The presence of IgA specific anti-bone antibodies was first investigated using indirect immunofluorescence on cryosections of fetal rat tibia (20-day pregnancy). Furthermore, samples were homogenized and total tissue extracts were subjected to Western blot analysis to confirm immunoreactivity. At diagnosis, sera from 51.5% (17/33) of celiac patients had antibodies that recognized antigenic structures in chondrocytes and the extracellular matrix along mature cartilage, bone interface, and perichondrium of fetal rat bone. Among controls, only two osteoporotic patients showed very low titles of anti-bone autoantibodies. The immunostaining was localized in areas where an active mineralization process occurred and was similar to the distribution of the native bone tissue transglutaminase. The frequency of patients with positive baseline titers of anti-bone antibodies diminished significantly after treatment (P = 0.048). Western blot assays confirmed the presence of autoantibodies in sera from patients with a positive immunofluorescence staining. Autoantibodies recognized a major protein band on tissue extracts with a molecular weight of 77-80 kDa, which could be displaced when sera were preadsorbed with human recombinant tissue transglutaminase. We provide original evidence that patients with celiac disease have IgA-type circulating autoantibodies against intra- and extracellular structures of fetal rat tibia. Our findings suggest that these antibodies recognize bone tissue transglutaminase as the autoantigen, and based on the localization of the immunoreactivity we speculate that they might have an active role in the pathophysiology of celiac disease-associated bone complications.

Value of a screening algorithm for celiac disease using tissue transglutaminase antibodies as first level in a population-based study

OBJECTIVE

Serological screening for celiac disease (CD) can detect a large number of otherwise undiagnosed patients based on the sequential evaluation of serological tests and intestinal biopsy. The aim of this study was to compare the screening value for CD of two different protocols for the same community-based population.

METHODS

We screened 1,000 consecutive subjects (497 women, age range 16-71 yr) attending a centralized laboratory for obligatory prenuptial blood tests. Serum samples obtained from all subjects were processed using two different protocols: I) a three-level classic screening consisting of the parallel use of IgG and IgA antigliadin antibodies as first level, followed by endomysial antibodies and total serum IgA for positive patients, and finally, intestinal biopsy of positive patients; and 2) a study screening protocol consisting of the parallel use of a commercial guinea pig antitissue transglutaminase antibody and total serum IgA as first line, endomysial antibodies (type IgA and/or IgG) for positive patients, and finally, intestinal biopsy.

RESULTS

The classic screening protocol identified five subjects who were eligible for intestinal biopsy, which confirmed the presence of CD in all (prevalence 5.0 x 1,000, 95% CI = 1.6-11.6). Using the study algorithm, we detected seven new patients including the five patients detected by the first protocol (prevalence 7.0 x 1,000, 95% CI = 2.8-14.4). The two additional patients diagnosed using the proposed algorithm had positive IgG antigliadin antibodies and normal total serum IgA and were not detected by the classic protocol. Both patients were endomysial antibodies positive. The comparative analysis showed that the classic approach was more expensive (U.S. $4,687 per new patient detected) compared with the proposed study algorithm (U.S. $3,006).

CONCLUSIONS

Our data showed that a new screening protocol using antitissue transglutaminase as first line followed by endomysial antibodies is a cost-effective screening and yielded more realistic figures of prevalence for CD in a community setting than the classic three-level sequential evaluation using antigliadin antibodies.

Azathioprine in refractory sprue: results from a prospective, open-label study

OBJECTIVE

Refractory sprue is a rare and severe malabsorptive disorder that mimics celiac disease but is refractory to a gluten-free diet and is without initial evidence of overt lymphoma. Treatment is largely empiric and often ineffective, with steroids and immunosuppression being the mainstream therapeutic options. The aim of this study was to evaluate prospectively the effect of azathioprine on a group of patients diagnosed with refractory sprue.

METHODS

We studied seven consecutive patients (five women and two men) with a well-defined diagnosis of refractory sprue and a lack of response to oral or parenteral steroids. At diagnosis, five patients had endoscopic evidence of ulcerative jejunitis, and five underwent exploratory laparotomy for exclusion of malignancies. The characteristic monoclonal TCRgamma gene rearrangement was shown in five of six patients studied. Patients were treated for a mean of 11 months (range 8-12 months), and clinical, biochemical, molecular, and histological parameters were reassessed at the end of the trial. The study was a prospective, open-label, non-placebo-controlled study using azathioprine (2 mg/kg/ day) plus oral prednisone (1 mg/kg/day). A gluten-free diet (n = 7) as well as enteral (n = 6) and parenteral nutrition (n = 5) were administered during the trial.

RESULTS

After treatment, five patients had a complete clinical remission, and biochemical and nutritional parameters were significantly improved. Steroids were tapered after the onset of azathioprine, and no patient was on steroids at the end of the trial. Intestinal histology improved significantly in all cases (normal histology in three cases and minor infiltration in the lamina propria in two). Two patients did not respond to treatment at any time and died in months 10 and 9, of an irreversible ventricular fibrillation and sepsis, respectively. No overt lymphoma was demonstrated during the follow-up.

CONCLUSIONS

The present study confirms earlier anecdotal reports on the efficacy of azathioprine in refractory sprue, with clear clinical and histological improvement shown in most patients. However, monoclonality persisted after treatment. We consider that a larger number of patients should be evaluated before a definitive recommendation is adopted for use of this drug in refractory sprue.

Is it necessary to screen for celiac disease in postmenopausal osteoporotic women?

Decreased bone mass is a frequent finding in celiac patients, and subclinical celiac disease (CD) appears to be unusually overrepresented among patients with idiopathic osteoporosis. Since silent CD may be more common than previously believed, it has been suggested that all osteoporotic patients should be checked for occult CD. The aim of this study was to explore the prevalence of CD in a well-defined population of postmenopausal osteoporotic women. We evaluated 127 consecutive postmenopausal patients (mean age: 68 years; range: 50-82 years) with verified osteoporosis. The observed prevalence of CD in this group was compared to that observed in a group of 747 women recruited for a population-based study. The screening algorithm used to diagnose CD was based on a 3-level screening using type IgA and IgG antigliadin antibodies (AGA) in all the patients (1st level) followed by antiendomysial antibodies (EmA) and total IgA (2nd level) of samples testing positive, and intestinal biopsy of positive cases (3rd level). At the end of the serological screening, only 1 of 127 osteoporotic women was eligible for jejunal biopsy showing a characteristic celiac flat mucosa (prevalence 7.9 x 1,000; 95% CI 0.2-43.1). In addition, CD was diagnosed in 6 of 747 women of the population-based study (prevalence: 8.0 x 1,000; 95% CI 3.3-18.3). There was no significant difference between the two groups. Therefore, our study showed that the prevalence of CD in postmenopausal osteoporotic women was lower than that reported in previous studies and similar to that of the general population. In conclusion, although the relatively small size of the group tested does not allow us to be conclusive, the results suggest that a case finding policy in postmenopausal osteoporosis would have a high cost/benefit ratio except for patients not responding to conventional therapies, or presenting borderline laboratory results.