Clinical and Immunologic Features of Ultra-Short Celiac Disease

Laboratory Testing for Celiac Disease: Clinical and Methodological Considerations

BACKGROUND

Celiac disease (CeD) has an estimated prevalence of 1%-3%. The classical clinical presentation is malabsorption, but now patients may present with more subtle symptoms such as constipation, osteoporosis, or iron deficiency anemia. Children may also present with poor growth.CeD has a strong genetic component, and high-risk groups include first-degree relatives with CeD, patients with co-existing autoimmune diseases, and patients with chromosomal aberrations.

CONTENT

Diagnostic tests for CeD include duodenal histology, serology, and genetic testing. Duodenal histology has traditionally been the gold standard of diagnosis. However, serological tests, especially IgA tissue transglutaminase antibodies (TTG-IgA), are widely used and diagnostic algorithms are based primarily on TTG-IgA as a starting point. Human leukocyte antigen typing may also be incorporated to determine genetic risk for CeD. Guidelines for children endorse biopsy avoidance provided high levels of TTG-IgA, with diagnostic accuracy being comparable to duodenal biopsy. Confirmation may be achieved by identifying IgA endomysial antibodies in a separate blood sample. Subjects with low positive TTG-IgA levels and subjects with IgA deficiency need a biopsy to establish a diagnosis of CeD. The clinical follow-up of CeD usually includes a repeat TTG-IgA examination. In adults, healing may be delayed or incomplete, and a rare consequence of refractory celiac disease is transformation to enteric T-cell lymphoma.

SUMMARY

Laboratory testing, in particular TTG-IgA, plays a central role in the diagnosis and has an accuracy comparable to histology. Diagnostic algorithms utilizing laboratory testing are critical for the development of novel strategies to improve diagnosis.

Clinical outcomes of potential coeliac disease: a systematic review and meta-analysis

OBJECTIVE

Potential coeliac disease (PCD) is characterised by positive serological and genetic markers of coeliac disease with architecturally preserved duodenal mucosa. The clinical outcomes and rates of progression to overt coeliac disease in patients with PCD remain uncertain. In this systematic review and meta-analysis, we aimed to evaluate the clinical outcomes of patients with PCD.

DESIGN

We searched Medline, Embase, Scopus and Cochrane Library from 1991 through May 2024 to identify studies evaluating the clinical outcomes of patients with PCD. The progression rates to villous atrophy, seroconversion and response to a gluten-free diet (GFD) were analysed. A random-effect meta-analysis was performed, and the results were reported as pooled proportions with 95% CIs.

RESULTS

Seventeen studies comprising 1010 patients with PCD were included in the final analyses. The pooled prevalence of PCD among patients with suspected coeliac disease was 16% (95% CI 10% to 22%). The duration of follow-up in most of the studies was at least 1 year, with follow-up periods within individual studies ranging from 5 months to 13 years. During follow-up, 33% (95% CI 18% to 48%; I2=96.4%) of patients with PCD on a gluten-containing diet developed villous atrophy, and 33% (95% CI 17% to 48%; I2=93.0%) had normalisation of serology. Among those who adhered to a GFD, 88% (95% CI 79% to 97%; I2=93.2%) reported symptomatic improvement.

CONCLUSION

Almost a third of patients with PCD develop villous atrophy over time, whereas a similar proportion experience normalisation of serology despite a gluten-containing diet. Most symptomatic patients benefit from a GFD. These findings highlight the importance of structured follow-up and individualised management for patients with PCD.

Role of Duodenal Bulb Biopsy in Diagnosing Suspected Celiac Disease in Adult Patients: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

Current guidelines recommend multiple biopsies from the first (D1) and second (D2) part of duodenum to establish a diagnosis of celiac disease. In this meta-analysis we aimed to find whether D1 biopsy can increase the diagnostic yield of adult celiac disease.

METHODS

Literature databases were searched until January 2023 for studies reporting diagnosis of celiac disease in the adult population using D1 biopsy. Meta-analysis was done using a random-effects model. Heterogeneity was assessed by I 2 % and 95% prediction interval statistics. Measured outcomes were diagnostic yield with D1 and D2 biopsies and from 4 versus 2 biopsy samples.

RESULTS

A total of 16 studies were included in the final analysis. The pooled diagnostic rate of celiac disease from D1 biopsy was 77.4% [95% CI (64.7-86.5, I 2 94%)] and from D2 biopsy was 75.3% [60.8-85.7, I 2 96%]. The pooled rate of increase in diagnostic yield with D1 biopsy was 6.9% I [4.6-10.2, I 2 66%]. The pooled diagnosis rate with 2 biopsy samples were 77.3% [50-92, I 2 93%] and 86.4% I [58.4-96.7, I 2 87%] from D1 and D2 respectively, whereas that with 4 biopsy samples were 83.3% [49.8-96.2, I 2 76%] and 70.5% I [51-84.6, I 2 96%] from D1 and D2, respectively, the difference being non-significant.

CONCLUSION

Our study demonstrates that taking 4 biopsy samples does not incur any additional diagnostic value over taking 2 biopsy samples from each duodenum segment. Although biopsy from the D1 and D2 has similar diagnostic yield in the adult population, there was an overall increase in diagnostic yield with D1 biopsy, especially in those with a patchy disease distribution.

New entity of adult ultra-short coeliac disease: the first international cohort and case-control study

BACKGROUND

Ultra-short coeliac disease (USCD) is defined as villous atrophy only present in the duodenal bulb (D1) with concurrent positive coeliac serology. We present the first, multicentre, international study of patients with USCD.

METHODS

Patients with USCD were identified from 10 tertiary hospitals (6 from Europe, 2 from Asia, 1 from North America and 1 from Australasia) and compared with age-matched and sex-matched patients with conventional coeliac disease.

FINDINGS

Patients with USCD (n=137, median age 27 years, IQR 21-43 years; 73% female) were younger than those with conventional coeliac disease (27 vs 38 years, respectively, p<0.001). Immunoglobulin A-tissue transglutaminase (IgA-tTG) titres at index gastroscopy were lower in patients with USCD versus conventional coeliac disease (1.8×upper limit of normal (ULN) (IQR 1.1-5.9) vs 12.6×ULN (IQR 3.3-18.3), p<0.001).Patients with USCD had the same number of symptoms overall (median 3 (IQR 2-4) vs 3 (IQR 1-4), p=0.875). Patients with USCD experienced less iron deficiency (41.8% vs 22.4%, p=0.006).Both USCD and conventional coeliac disease had the same intraepithelial lymphocytes immunophenotype staining pattern; positive for CD3 and CD8, but not CD4.At follow-up having commenced a gluten-free diet (GFD) (median of 1181 days IQR: 440-2160 days) both USCD and the age-matched and sex-matched controls experienced a similar reduction in IgA-tTG titres (0.5 ULN (IQR 0.2-1.4) vs 0.7 ULN (IQR 0.2-2.6), p=0.312). 95.7% of patients with USCD reported a clinical improvement in their symptoms.

INTERPRETATION

Patients with USCD are younger, have a similar symptomatic burden and benefit from a GFD. This study endorses the recommendation of D1 sampling as part of the endoscopic coeliac disease diagnostic workup.

Diagnosis of Seronegative and Ultrashort Celiac Disease

In its conventional form, celiac disease (CeD) is characterized by both positive serology and flat villi in the duodenum, and is well known by gastroenterologists and general practitioners. The aim of this review was to shed light on 2 neglected and not yet well-defined celiac phenotypes, that is, seronegative and ultrashort CeD. Seronegative CeD can be suspected in the presence of flat villi, positive HLA-DQ2 and/or HLA-DQ8, and the absence of CeD antibodies. After ruling out other seronegative enteropathies, the diagnosis can be confirmed by both clinical and histologic improvements after 1 year of a gluten-free diet. Ultrashort CeD is characterized by the finding of flat villi in the duodenal bulb in the absence of mucosal damage in the distal duodenum and with serologic positivity. Data on the prevalence, clinical manifestations, histologic lesions, genetic features, and outcome of seronegative and ultrashort CeD are inconclusive due to the few studies available and the small number of patients diagnosed. Some additional diagnostic tools have been developed recently, such as assessing intestinal transglutaminase 2 deposits, flow cytometry technique, microRNA detection, or proteomic analysis, and they seem to be useful in the identification of complex cases. Further cooperative studies are highly desirable to improve the knowledge of these 2 still-obscure variants of CeD.

Measured levels of positive transglutaminase 2 antibodies are not associated with presentation or incidental endoscopic findings at celiac disease diagnosis

OBJECTIVES

It has been suggested that celiac disease could be diagnosed non-invasively in adults with transglutaminase antibody (TGA) levels >10x upper limit of normal (ULN). It is, however, unclear if high values signify more advanced disease and higher risk of co-morbidities. We investigated the association between the TGA levels, clinical characteristics and non-celiac endoscopic findings.

METHODS

Medical data on 450 celiac disease patients at diagnosis were collected. They were further divided into those with high positive (>10x ULN, n = 164), moderately positive (1-10x ULN, n = 219), and negative (n = 67) TGA.

RESULTS

Median age of patients was 50 years and 60% were women. Patients with negative TGA were older (median age 58 vs. 51 vs. 46 years respectively, p = 0.002) and had more often weight loss (27% vs. 10% vs. 9%, p < 0.001) and abdominal pain or dyspepsia (40% vs 27% vs. 22%, p = 0.017) than did those with moderately positive/high TGA. The groups did not differ in sex, BMI, or other symptoms. Major endoscopic findings included one esophageal adenocarcinoma presenting with dysphagia, six esophagitis, three gastric ulcers, and 39 H. Pylori or other active gastritis. High, moderately positive or negative TGA levels were not associated with these findings in crude or age-adjusted analyses.

CONCLUSIONS

Presentation was similar in patients with moderate or high levels of TGA, whereas patients with negative TGA were different. The level of TGA was not associated with incidental endoscopic findings and the only malignancy presented with an alarm symptom atypical to celiac disease.

Reduced expression of Ankyrin-G and E-cadherin in duodenal mucosal biopsy of subjects with celiac disease

Confirmatory diagnosis of celiac disease (CD) include histopathology of duodenal biopsy and tissue trans-glutaminase-IgA. Identification of tissue-specific histological markers is warranted to improve the diagnosis. A genetic study in CD identified the association of ankyrin-G that connects E-cadherin with β2-spectrin in epithelial cells of the duodenal tissue. We attempted to investigate the differential expression of ankyrin-G, E-cadherin and β2-spectrin in duodenal biopsy of CD subjects compared to non-CD controls. Duodenal tissue was collected from 83 study participants, of which 50 were CD, and 33 were non-CD controls. Whole RNA was isolated from 32 CD and 23 non-CD controls from available tissues, and differential mRNA expression was measured using real-time PCR. Tissue sections from 18 CD cases and 10 non-CD controls were immunostained using monoclonal antibodies. Tissue immunohistochemistry were evaluated for differential expression and pattern of expression. RT-PCR revealed significantly reduced expression of ankyrin-G (fold change=0.63; p=0.03) and E-cadherin (fold change=0.50; p=0.02) among CD subjects compared to non-CD controls. Tissue immunohistochemistry confirmed the reduced expression of ankyrin-G and E-cadherin in CD. Differential expression is grossly limited within the outer columnar epithelial cell layer. Expression fold change of E-cadherin was seen to partially correlate with the serum tTG level (r=0.4; p=0.04). In CD, reduced expression of two key cytoskeletal proteins (ankyrin-G and E-cadherin) in duodenum mucosa was observed, which indicates its implication in disease biology and could be tested as a tissue-specific biomarker for CD. Functional studies may unravel the specific contribution of these proteins in CD pathophysiology.

Cutaneous Disorders Masking Celiac Disease: Case Report and Mini Review with Proposal for a Practical Clinical Approach

Celiac disease (CD) is an immune-mediated systemic gluten-related disorder characterized by a wide spectrum of intestinal and extra-intestinal manifestations, including damage to cutaneous and connective tissue. We report a rare case of chronic severe dermatitis involving connective tissue and cutaneous vascular vessels as the main clinical presentation of undiagnosed seronegative gluten disorder. A gluten-free diet dramatically improved the intestinal and cutaneous clinical damage in the patient. Pitfalls and the steps of differential diagnosis are described. We also review the literature regarding studies of CD and connective tissue diseases to extend the knowledge of these rare associations. We propose a practical diagnostic approach in suspected CD in autoimmune cutaneous disorders.

Prevalence of Coagulopathy in Patients with Celiac Disease: A Single-Center Retrospective Case-Control Study

Introduction: Despite being one of the most frequent chronic digestive diseases worldwide, with a prevalence of 1%, celiac disease (CD) remains severely underdiagnosed. Among the instruments used to improve its diagnostic rate, hematologic parameters have been proposed as screening tests to select patients with an increased probability of having CD. Assessment of coagulation is included in routine check-ups, and CD has been reported to be associated with coagulopathy. We aimed to assess if subtle changes in coagulation tests could be used in clinical practice to prompt testing for CD. Methods: We retrospectively recruited all patients with clinical suspicion for CD during a study period of 7 years (between 2015 and 2022), who were tested using IgA tissue transglutaminase (tTG) serology and serum total IgA (IgG tTG in case of IgA deficiency) and who underwent upper gastrointestinal endoscopy with multiple biopsy sampling of the duodenal bulb and distal duodenum. We stratified patients into three groups: newly diagnosed CD, gluten-free diet-treated CD, and non-CD controls. Results: Altogether, there were 133 CD patients (71 newly diagnosed, 62 GFD-treated) and 57 non-CD controls. Mean age and gender distribution were similar among the three groups: 43.3 years for newly diagnosed CD, 41.6 years for non-CD controls, and 44 years for GFD-treated CD patients, with a male gender distribution of 21.1%, 28%, and 24.1%, respectively. Among the included newly diagnosed CD patients, 14% had a prolonged INR. The mean INR was slightly higher in newly diagnosed CD patients, compared to GFD-treated CD patients and non-CD controls: 1.12 ± 0.30, 1.02 ± 0.83, and 1.00 ± 0.08, respectively (p = 0.009). Consequently, prothrombin activity was slightly lower in newly diagnosed CD patients, compared to GFD-treated CD and non-CD controls: 94.9 ± 19.3%, 102.3 ± 12.8%, and 101.9 ± 15.15, respectively. Interestingly, after GFD, the mean INR and prothrombin activity of CD individuals reached a value similar to that of non-CD controls. Conclusions: Subtle changes in INR, defined as a value within the normal range, but closer to the upper limit, could be an indicator of probability for CD.

Is There a Time and a Place for the Gluten-Free Diet in Potential Celiac Disease?

Potential celiac disease (PCD) is characterized by the absence of villous atrophy on duodenal biopsies (Marsh 0 or 1) despite positive celiac serology and HLA DQ2 or DQ8 heterodimers. Recent epidemiological studies report that PCD represents one fifth of the total CD diagnoses. Compared to patients with CD, the majority of adult patients with PCD show lower rates of nutrient deficiencies and extraintestinal symptoms at diagnosis. Recommending a gluten-free diet (GFD) to PCD patients depends on whether they have symptoms or not. A significant clinical improvement is reported by symptomatic patients, but for asymptomatic PCD, diet implementation is still a matter of debate. Some questions remain to be answered: does PCD serve as an intermediary phase leading to the progression of true CD? Is it reasonable to hypothesize that PCD and active CD represent different manifestations of the same condition? Is there a potential for both underdiagnosis and overdiagnosis of CD in those who may have the condition? Additional research is required to address these inquiries and ascertain the specific subset of people with potential progression to overt CD, as well as to determine the potential advantages of early implementation of a GFD for these individuals. The investigation of risk factors in CD warrants examination of variables such as the timing of diagnosis, the genetic profile, the extent of gluten exposure, and the composition of the microbiome.

Computer-Based Diagnosis of Celiac Disease by Quantitative Processing of Duodenal Endoscopy Images

Celiac disease (CD) is a lifelong chronic autoimmune systemic disease that primarily affects the small bowel of genetically susceptible individuals. The diagnostics of adult CD currently rely on specific serology and the histological assessment of duodenal mucosa on samples taken by upper digestive endoscopy. Because of several pitfalls associated with duodenal biopsy sampling and histopathology, and considering the pediatric no-biopsy diagnostic criteria, a biopsy-avoiding strategy has been proposed for adult CD diagnosis also. Several endoscopic changes have been reported in the duodenum of CD patients, as markers of villous atrophy (VA), with good correlation with serology. In this setting, an opportunity lies in the automated detection of these endoscopic markers, during routine endoscopy examinations, as potential case-finding of unsuspected CD. We collected duodenal endoscopy images from 18 CD newly diagnosed CD patients and 16 non-CD controls and applied machine learning (ML) and deep learning (DL) algorithms on image patches for the detection of VA. Using histology as standard, high diagnostic accuracy was seen for all algorithms tested, with the layered convolutional neural network (CNN) having the best performance, with 99.67% sensitivity and 98.07% positive predictive value. In this pilot study, we provide an accurate algorithm for automated detection of mucosal changes associated with VA in CD patients, compared to normally appearing non-atrophic mucosa in non-CD controls, using histology as a reference.

Computer-Based Diagnosis of Celiac Disease by Quantitative Processing of Duodenal Endoscopy Images

Celiac disease (CD) is a lifelong chronic autoimmune systemic disease that primarily affects the small bowel of genetically susceptible individuals. The diagnostics of adult CD currently rely on specific serology and the histological assessment of duodenal mucosa on samples taken by upper digestive endoscopy. Because of several pitfalls associated with duodenal biopsy sampling and histopathology, and considering the pediatric no-biopsy diagnostic criteria, a biopsy-avoiding strategy has been proposed for adult CD diagnosis also. Several endoscopic changes have been reported in the duodenum of CD patients, as markers of villous atrophy (VA), with good correlation with serology. In this setting, an opportunity lies in the automated detection of these endoscopic markers, during routine endoscopy examinations, as potential case-finding of unsuspected CD. We collected duodenal endoscopy images from 18 CD newly diagnosed CD patients and 16 non-CD controls and applied machine learning (ML) and deep learning (DL) algorithms on image patches for the detection of VA. Using histology as standard, high diagnostic accuracy was seen for all algorithms tested, with the layered convolutional neural network (CNN) having the best performance, with 99.67% sensitivity and 98.07% positive predictive value. In this pilot study, we provide an accurate algorithm for automated detection of mucosal changes associated with VA in CD patients, compared to normally appearing non-atrophic mucosa in non-CD controls, using histology as a reference.

The Characteristics of Isolated Bulb Celiac Disease in Children

OBJECTIVES

Mucosal injury in celiac disease (CD) patients can be patchy, and up to 12% of CD patients can have mucosal changes limited to the duodenal bulb. Hence, recent guidelines recommend obtaining bulb biopsies in addition to distal duodenum. This study aimed to describe a cohort of children with isolated bulb CD and assess the benefit of separating bulb biopsies.

METHODS

A retrospective chart review between January 2011 and January 2022 at 2 medical centers was conducted. We included children with CD who underwent endoscopy with separated biopsies from the bulb and distal duodenum. A blinded pathologist performed Marsh-Oberhuber grading on selected cases.

RESULTS

We identified 224 CD patients, of which 33 (15%) had histologically confirmed isolated bulb CD. Patients with isolated bulb CD were older at diagnosis (10 vs 8 years; P = 0.03). Median anti-tissue transglutaminase immunoglobulin A (TTG IgA) level was lower in isolate bulb CD (2.8 vs 16.7 times the upper limit of normal [ULN], P < 0.001). Almost 88% (29/33) of isolated bulb CD patients had an anti-TTG IgA value of less than 10 times the ULN. Time to anti-TTG IgA normalization (mean 14 months) was similar between the 2 groups. A pathologist review of diagnostic biopsies could not distinguish between the bulb and distal duodenum biopsies in approximately one-third of the reviewed samples.

CONCLUSIONS

Separating bulb from distal duodenum biopsies can be considered during CD diagnosis, particularly in children with anti-TTG IgA levels less than 10 times the ULN. Larger prospective cohorts are needed to decide whether isolated bulb CD is a unique cohort or an early stage of the conventional CD.

Updates in the diagnosis and management of coeliac disease

Coeliac disease is a common autoimmune disorder induced by ingesting gluten, the protein component of wheat, barley, and rye. It is estimated that one-in-hundred people worldwide have coeliac disease, of whom the majority remain undiagnosed. Coeliac disease is characterized by a wide range of gastrointestinal and extraintestinal symptoms but can also present asymptomatically. Diagnosing coeliac disease depends on the concordance of clinical, serological and histopathological data. However, the diagnosis can be challenging and frequently overlooked. Undiagnosed coeliac disease is associated with an increased risk of complications and detrimental effects on quality of life. Early diagnosis and treatment of coeliac disease are necessary to reduce the risk of long-term complications.

[Immunopathology of the small intestine]

The gastrointestinal tract is the site of exciting immunological interactions between the epithelium and the mucosa-associated lymphoid tissue, leading to the immune response to food and microbial antigens in the digestive lumen. The objective of this review is to present the main dysimmune pathologies of the digestive tract leading to an enteropathy. As examples, we describe celiac and non-celiac enteropathies to clarify a florid diagnostic framework, by identifying a spectrum of elementary lesions, which must be confronted with the clinico biological context of the patient to orient the diagnosis. The microscopic lesions observed are most often non-specific and may be encountered in several diagnostic settings. Moreover, it is a set of elementary lesions in each clinical context that will orient the diagnostic framework. Celiac disease is the main etiology of enteropathy with villous atrophy, its diagnosis is multidisciplinary and there are many differential diagnoses. We will discuss celiac disease lymphomatous complications as enteropathy associated T-cell lymphoma including refractory sprue type 2. We will then present the non-celiac enteropathies. Among these, enteropathies of unknown etiology may be associated with a primary immune deficiency that may be reflected by florid lymphoid hyperplasia of the gastrointestinal tract and/or be associated with an infectious etiology that should also be constantly sought. Finally, we will discuss of induced enteropathy by new immunomodulatory treatments.

The debate in the diagnosis of coeliac disease - time to go 'no-biopsy'?

PURPOSE OF REVIEW

Duodenal biopsies have been central to making a diagnosis of coeliac disease for the last 70 years. Recent paediatric guidelines have reduced the emphasis on duodenal biopsies with the incorporation of a 'no-biopsy' arm to the diagnostic pathway. This review discusses the no-biopsy approach in adults and highlights advances in alternative (non-biopsy) diagnostic modalities in coeliac disease.

RECENT FINDINGS

Evidence suggests that a no-biopsy approach for the diagnosis of adult coeliac disease is accurate. However, a number of factors still favour duodenal biopsy sampling in specific patient groups. Moreover, several factors need to be considered if this pathway is implemented into local gastroenterology services.

SUMMARY

Duodenal biopsies remain an important step in the diagnosis of adult coeliac disease. However, an alternative approach that removes the necessity for biopsies may be an option in selected adults. If further guidelines incorporate this pathway, then efforts should focus on supporting a dialogue between primary and secondary care to facilitate the appropriate implementation of this approach.

Histologic evaluation in the diagnosis and management of celiac disease: practical challenges, current best practice recommendations and beyond

Celiac disease (CD) is an immunoallergic enteropathy affecting genetically susceptible individuals upon dietary exposure to gluten. In current clinical practice, the diagnosis of CD is based on a combination of clinical, serologic, and histologic factors with the possible exception of pediatric patients. Histopathologic evaluation of small intestinal tissue plays a critical role in the disease diagnosis and management, despite many practical challenges. Recently published best practice guidelines help to standardize biopsy sample procurement, tissue preparation, histology interpretation, and reporting, to optimize patient care. In addition, an increasing demand for monitoring the disease course, particularly demonstrating the efficacy of dietary and nondietary interventions for disease management, calls for the use of quantitative histology. With the advent of a gradual transition toward digital pathology in routine diagnostic practice, quantitative histopathologic evaluation in CD shows a promising future.

Guidelines of the Italian societies of gastroenterology on the diagnosis and management of coeliac disease and dermatitis herpetiformis

INTRODUCTION

Coeliac disease and dermatitis herpetiformis are immune-mediated diseases triggered by the consumption of gluten in genetically predisposed individuals. These guidelines were developed to provide general practitioners, paediatricians, gastroenterologists, and other clinicians with an overview on the diagnosis, management and follow-up of coeliac patients and those with dermatitis herpetiformis.

METHODS

Guidelines were developed by the Italian Societies of Gastroenterology. Following a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the certainty of the evidence. Statements and recommendations were developed by working groups consisting of gastroenterologists and a paediatrician with expertise in this field.

RESULTS

These guidelines provide a practical guidance for the diagnosis, management and follow-up of coeliac patients and dermatitis herpetiformis in children and adults, both in primary care and in specialist settings. We developed four sections on diagnosis, gluten-free diet, follow-up and risk of complications in adults, one section focused on diagnosis and follow-up in children and one on the diagnosis and management of dermatitis herpetiformis.

CONCLUSIONS

These guidelines may support clinicians to improve the diagnosis and management of patients with coeliac disease.

The global burden of coeliac disease: opportunities and challenges

Coeliac disease is a systemic disorder characterized by immune-mediated enteropathy, which is caused by gluten ingestion in genetically susceptible individuals. The clinical presentation of coeliac disease is highly variable and ranges from malabsorption through solely extra-intestinal manifestations to asymptomatic. As a result, the majority of patients with coeliac disease remain undiagnosed, misdiagnosed or experience a substantial delay in diagnosis. Coeliac disease is diagnosed by a combination of serological findings of disease-related antibodies and histological evidence of villous abnormalities in duodenal biopsy samples. However, variability in histological grading and in the diagnostic performance of some commercially available serological tests remains unacceptably high and confirmatory assays are not readily available in many parts of the world. Currently, the only effective treatment for coeliac disease is a lifelong, strict, gluten-free diet. However, many barriers impede patients' adherence to this diet, including lack of widespread availability, high cost, cross-contamination and its overall restrictive nature. Routine follow-up is necessary to ensure adherence to a gluten-free diet but considerable variation is evident in follow-up protocols and the optimal disease management strategy is not clear. However, these challenges in the diagnosis and management of coeliac disease suggest opportunities for future research.

Ultra-short celiac disease exhibits differential genetic and immunophenotypic features compared to conventional celiac disease

BACKGROUND

Ultra-short coeliac disease (USCD) is a novel celiac disease (CD) subtype limited to the duodenal bulb (D1). HLA haplotypes and flow cytometry have not been assessed yet.

AIMS

To compare genetic, clinical, serologic, histopathologic and inmmunophenotypic parameters between USCD and conventional celiac disease (CCD) patients.

METHODS

Prospective single-center study in children and adult patients undergoing duodenal biopsies on a gluten-containing diet. Biopsies for histology and flow cytometry were taken separately from D1 and distal duodenum. Biopsies in seronegative patients with celiac lymphogram were repeated after 2 years on a gluten-free diet.

RESULTS

Among 505 included patients, 127 were diagnosed with CD, of whom 7 (5.5%) showed USCD. HLADQ2 was significantly less common in USCD compared to CCD (71% vs. 95%, p 0.003). Likewise, USCD patients showed more frequent non-significant seronegativity (28% vs. 8%, p 0.07) and significantly lower titrations (7-15 IU/ml) of tissue transglutaminase antibodies (tTG-IgA) (60% vs. 13%, p<0.001). Biopsies from D1 revealed significant less NK cells down-expression in USCD patients (1.4 vs. 5, p 0.04).

CONCLUSIONS

Up to 5.5% of CD patients showed USCD. A lower frequency of HLADQ2, along with less serum tTG-IgA titration and duodenal NK cell suppression, were differential features of USCD.

Upper Gastrointestinal Tract Associated Lesions in Patients with Newly Diagnosed Celiac Disease

(1) Background: Currently available guidelines require upper gastrointestinal (GI) endoscopy with biopsy sampling for adult celiac disease (CD) diagnosis. Based on the pediatric experience, there has been a growing interest if serology-based diagnosis would be possible for adult CD also. Our aim was to analyze the associated upper GI tract lesions in newly diagnosed CD patients, to see if significant associated pathology is detected during index endoscopy, which might impact patient management not related to CD. (2) Methods: We performed a retrospective analysis of newly diagnosed CD cases diagnosed over a period of 7 years (2014–2020). Demographic, clinical, laboratory, endoscopy and histopathology data were collected from the patients’ charts. Diagnosis was set according to ACG Guideline 2013. (3) Results: Altogether 79 patients were recruited for this study purpose, 75.9% female, median age 39 years. All patients had positive CD-specific serology and atrophic mucosal injury in duodenal biopsy samples. Besides villous atrophy, associated endoscopic findings were detected in 42/79 (53.16%) of patients. Most of the gastric lesions were minor endoscopic findings—small sliding hiatal hernias, non-specific chronic gastritis, but we also found two cases of peptic ulcers, one case of metaplastic gastritis, six cases of atrophic gastritis and one subepithelial lesion. Only one patient had changes in the duodenum except CD-related findings—an inflammatory polyp in the duodenal bulb. No malignancies were found. (4) Conclusions: In our cohort, there was a significant number of newly diagnosed CD patients who had associated lesions during the index upper GI endoscopy, but most of them were minor endoscopic findings.

Endoscopic tissue sampling - Part 1: Upper gastrointestinal and hepatopancreatobiliary tracts. European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that, where there is a suspicion of eosinophilic esophagitis, at least six biopsies should be taken, two to four biopsies from the distal esophagus and two to four biopsies from the proximal esophagus, targeting areas with endoscopic mucosal abnormalities. Distal and proximal biopsies should be placed in separate containers.Strong recommendation, low quality of evidence. 2: ESGE recommends obtaining six biopsies, including from the base and edge of the esophageal ulcers, for histologic analysis in patients with suspected viral esophagitis.Strong recommendation, low quality of evidence. 3: ESGE recommends at least six biopsies are taken in cases of suspected advanced esophageal cancer and suspected advanced gastric cancer.Strong recommendation, moderate quality of evidence. 4: ESGE recommends taking only one to two targeted biopsies for lesions in the esophagus or stomach that are potentially amenable to endoscopic resection (Paris classification 0-I, 0-II) in order to confirm the diagnosis and not compromise subsequent endoscopic resection.Strong recommendation, low quality of evidence. 5: ESGE recommends obtaining two biopsies from the antrum and two from the corpus in patients with suspected Helicobacter pylori infection and for gastritis staging.Strong recommendation, low quality of evidence. 6: ESGE recommends biopsies from or, if endoscopically resectable, resection of gastric adenomas.Strong recommendation, moderate quality of evidence. 7: ESGE recommends fine-needle aspiration (FNA) and fine-needle biopsy (FNB) needles equally for sampling of solid pancreatic masses.Strong recommendation, high quality evidence. 8: ESGE suggests performing peroral cholangioscopy (POC) and/or endoscopic ultrasound (EUS)-guided tissue acquisition in indeterminate biliary strictures. For proximal and intrinsic strictures, POC is preferred. For distal and extrinsic strictures, EUS-guided sampling is preferred, with POC where this is not diagnostic.Weak recommendation, low quality evidence. 9: ESGE suggests obtaining possible non-neoplastic biopsies before sampling suspected malignant lesions to prevent intraluminal spread of malignant disease.Weak recommendation, low quality of evidence. 10: ESGE suggests dividing EUS-FNA material into smears (two per pass) and liquid-based cytology (LBC), or the whole of the EUS-FNA material can be processed as LBC, depending on local experience.Weak recommendation, low quality evidence.

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.

Nonbiopsy Approach for Celiac Disease Is Accurate When Using Exact Duodenal Histomorphometry: Prospective Study in 2 Countries

GOALS

To test the accuracy of serology-based criteria for diagnosing celiac disease utilizing quantitative histomorphometry.

BACKGROUND

The revised European pediatric guidelines allow noninvasive celiac disease diagnosis for a subgroup of children. However, in some of the studies on this issue, the positive predictive value (PPV) of serology has remained suboptimal, possibly because of challenges of histopathology as the reference standard.

STUDY

Prospectively enrolled children with transglutaminase 2 antibodies (TGA) above the upper limit of normal (ULN) underwent blood sampling and duodenal biopsy in Finland and Romania. Those with TGA ≥10× ULN, positive endomysium antibodies (EmA), and disease-associated genetics were considered to fulfill triple criteria for celiac disease. Initial histopathologic analysis was conducted using grouped classification, whereupon centralized morphometry was performed.

RESULTS

Altogether 88 (54%) children were triple positive. In local evaluation, 99% of triple-positive children and 73% of children with TGA <10× ULN had celiac disease. These figures increased to 100% and 85% after more precise morphometric analysis. Triple-positive children had more anemia and higher median EmA and liver enzyme values than those with TGA<10× ULN; the groups were comparable in other clinical features and laboratory parameters.

CONCLUSIONS

When applied as recommended, the nonbiopsy strategy had already yielded excellent PPV regardless of the site of diagnosis or clinical presentation in the local analysis. PPV further increased to 100% with standardized duodenal morphometry.

Best practices of handling, processing, and interpretation of small intestinal biopsies for the diagnosis and management of celiac disease: A joint consensus of Indian association of pathologists and microbiologists and Indian society of gastroenterology

The Indian Association of Pathologists and Microbiologists (IAPM) and Indian Society of Gastroenterology (ISG) decided to make a joint consensus recommendation for handling, processing, and interpretation of SI biopsies for the diagnosis and management of celiac disease (CD) recognizing the inhomogeneous practice of biopsy sampling, orientation, processing, and interpretation. A modified Delphi process was used to develop this consensus document containing a total of 42 statements and recommendations, which were generated by sharing the document draft, incorporating expert's opinion, followed by three cycles of electronic voting as well as a full-day face-to-face virtual ZOOM meeting and review of supporting literature. Of the 42 statements, 7 statements are on small intestinal (SI) biopsy in suspected patients of CD, site and the number of biopsies; 7 on handling, fixative, orientation, processing, and sectioning in pathology laboratories; 2 on histological orientation; 13 statements on histological interpretation and histological grading; 3 on the assessment of follow-up biopsies; 2 statements on gluten-free diet (GFD)-nonresponsive CD; 4 on challenges in the diagnosis of CD; 2 statements each on pathology reporting protocol and training and infrastructure in this area. The goal of this guideline document is to formulate a uniform protocol agreed upon both by the experienced pathologists and gastroenterologists to standardize the practice, improve the yield of small bowel biopsy interpretation, patients' compliance, overall management in CD, and generate unified data for patient care and research in the related field.

AGA Clinical Practice Update on the Evaluation and Management of Seronegative Enteropathies: Expert Review

DESCRIPTION

Our aim was to provide a consensus statement for the best approaches for diagnosis and management of patients with suspected enteropathy, but negative results from serologic tests for celiac disease (seronegative enteropathy).

METHODS

We collected findings from published cohort, case-control, and cross-sectional studies of diagnosis and case series and descriptive studies of management of patients believed to have celiac disease or other enteropathies unrelated to gluten, but negative results from serologic tests. BEST PRACTICE ADVICE 1: Review histologic findings with experienced pathologists who specialize in gastroenterology. BEST PRACTICE ADVICE 2: Serologic tests are essential for an accurate diagnosis of celiac disease. For patients with suspected celiac disease but negative results from serologic tests, total IgA level should be measured; patients should also be tested for anti-tissue transglutaminase, IgA against deamidated gliadin peptide, and endomysial antibody (IgA). Patients with total IgA levels below the lower limit of detection and IgG against tissue transglutaminase or deamidated gliadin peptide, or endomysial antibody, should be considered to have celiac disease with selective IgA deficiency rather than seronegative celiac disease. BEST PRACTICE ADVICE 3: Patients' diets should be carefully reviewed and duodenal biopsies should be collected and analyzed at the time of serologic testing to determine exposure to gluten and accuracy of test results. BEST PRACTICE ADVICE 4: Thorough medication histories should be collected from patients, with attention to angiotensin II receptor blockers, such as olmesartan, along with travel histories to identify potential etiologies of villous atrophy. This will guide additional testing. BEST PRACTICE ADVICE 5: Patients should be analyzed for disease-associated variants in human leukocyte antigen genes; results must be carefully interpreted. Negative results can be used to rule out celiac disease in seronegative patients. BEST PRACTICE ADVICE 6: Patients with suspected celiac disease who are seronegative but have villous atrophy and genetic risk factors for celiac disease must undergo endoscopic evaluation after 1-3 years on a gluten-free diet to evaluate improvements in villous atrophy. A diagnosis of seronegative celiac disease can then be confirmed based on clinical and histologic markers of improvement on the gluten-free diet. BEST PRACTICE ADVICE 7: Seronegative patients with an identified cause for enteropathy should be treated accordingly; a follow-up biopsy might or might not be necessary. BEST PRACTICE ADVICE 8: Patients with persistent signs and symptoms who do not respond to a gluten-free diet, and for whom no etiology of enteropathy is ultimately identified, should be treated with budesonide.

CONCLUSIONS

These best practice guidelines will aid in diagnosis and management of patients with suspected celiac disease, but negative results from serologic tests.

Duodenal bulb biopsy in the diagnostic work-up of coeliac disease

Coeliac disease (CD) is an autoimmune enteropathy which can present with patchy mucosal lesions. The aim of the present study is to investigate the significance of duodenal bulb biopsy in the diagnostic work-up of CD in both pediatric and adult patients, and to highlight the key points for pathologists. D1 (duodenal bulb) and D2 (distal duodenum) biopsies of 153 newly diagnosed serology-positive CD patients were evaluated for villous/crypt ratio and intraepithelial lymphocyte (IEL) counts on CD3-stained slides and were classified according to Marsh. Mucosal pathology was patchy in 15% (13% only D1 and 2% only D2) of patients, and 85% of patients had diffuse mucosal pathology involving both D1 and D2 biopsies which showed concordant histology in 60% and discordant in 25% of the cases. Though majority of the patients (75%) with only D1 involvement were pediatric cases, no significant difference was found between pediatric and adult patients when all cases were considered (17 vs 14%). Our results clearly indicate that without D1 sampling, diagnosis of CD would have been missed in a significant number of cases (13%), thereby highlighting the importance of taking duodenal biopsies from multiple sites in the diagnostic work-up of CD. We, therefore, conclude that every biopsy piece from both D1 and D2 should be carefully evaluated for the whole spectrum of mucosal changes caused by gluten ingestion and classified using a scheme based on Marsh to allow recognition of mild lesions.

Ocular manifestations in celiac disease: an overview

PURPOSE

To review and highlight the ocular manifestations associated with celiac disease (CD) and presentation of their pathogenetic mechanisms.

METHODS

A thorough review of the literature was performed using PubMed to identify articles about serrated polyposis syndrome. The search was performed using the search string: ("celiac disease" OR "coeliac disease") AND ("ocular manifestations" OR "eye" OR "orbitopathy" OR "uveitis" OR "neuro-ophthalmic manifestations"). Only articles in English were reviewed.

RESULTS

Several ocular symptoms and disorders have been associated with CD and are a result of defective intestinal absorption and immunological mechanisms. These include nyctalopia, dry eye, cataract, thyroid-associated orbitopathy, uveitis, central retinal vein occlusion and neuro-ophthalmic manifestations. In addition, CD-related ocular disease may represent the first manifestation of CD.

CONCLUSION

CD may hold accountable for the development of ocular diseases of obscure etiology.

Diagnostic accuracy and applicability of intestinal auto-antibodies in the wide clinical spectrum of coeliac disease

BACKGROUND

Intestinal coeliac auto-antibodies are the marker of coeliac disease (CD). Since the determination of these antibodies is still not widely available, we used immunoassays to identify the most suitable technology for revealing intestinal auto-antibodies in the wide clinical spectrum of CD.

METHODS

Intestinal auto-antibodies have been prospectively investigated in CD suspected children using two immunoassays: intestinal-deposits of IgA anti-tissue transglutaminase antibodies (anti-tTG) and biopsy-culture IgA anti-endomysium (AEA). Intestinal IgM antibodies have been determined in IgA-deficient subjects.

FINDINGS

Two-hundred and twenty-one suspected CD patients were enrolled. Intestinal antibodies were tested positive for both assays in classical CD patients (n = 178) with villous atrophy and positive serum-CD antibodies, potential CD patients (n = 16) with normal intestinal mucosa and positive serum-CD antibodies, and pre-potential CD patients (n = 14) with normal intestinal mucosa and negative serum-CD antibodies. In 13/221 with normal intestinal mucosa, negative CD-serum antibodies and negative intestinal antibodies CD has been excluded. All classical, 14/16 potential and 11/14 pre-potential CD patients on gluten-free diet (GFD) improved their symptoms. In 9/11 pre-potential patients intestinal antibodies disappeared on GFD. Both assays were negative in 69/71 control subjects. The two assays showed high diagnostic sensitivity (100%) and specificity (99%).

INTERPRETATION

Intestinal CD-antibodies make prompt diagnosis in the wide clinical spectrum of CD reducing the delay in diagnosis and treatment, especially in pre-potential CD patients. The easy handling biopsy culture assay is an effective diagnostic tool which should be carried out by any gastroenterology unit to recognize all CD clinical manifestations.

FUNDING

Interreg Central-Europe, IRCCS "Burlo Garofolo".

Statement on Best Practices in the Use of Pathology as a Diagnostic Tool for Celiac Disease: A Guide for Clinicians and Pathologists

Small intestinal biopsy interpretation has been the cornerstone for the diagnosis of celiac disease for over 50 years. Despite the existence of sensitive and specific serological tests, duodenal mucosal biopsies continue to be obtained in the vast majority of patients in whom a diagnosis of celiac disease is being considered. The accurate evaluation of these biopsies requires coordination and information sharing between the gastroenterologist, laboratory, and pathologist in order to optimize tissue sampling, preparation and interpretation. This document, a collaboration between the Rodger C. Haggitt Gastrointestinal Pathology Society and the North American Association for the Study of Celiac Disease, is intended to provide clinicians and pathologists with a summary of best practices in the use of endoscopy and biopsy for patients with suspected celiac disease. The authors present a comprehensive and critical appraisal of the literature with respect to the topics of endoscopic findings, best methods for the obtaining biopsies, completing the pathology form and pathologic assessment, including evaluating intraepithelial lymphocytes and villous architecture. A discussion of conditions with overlapping pathologic findings in duodenal mucosal biopsies is presented. In order to provide additional guidance for challenging situations, the authors include an appendix containing practical suggestions. This review may be utilized in interdisciplinary discussions to optimize care for patients with possible celiac disease.

Hematologic Manifestations in Celiac Disease-A Practical Review

Celiac disease (CD) is a systemic autoimmune disease driven by gluten-ingestion in genetically predisposed individuals. Although it primarily affects the small bowel, CD can also involve other organs and manifest as an extraintestinal disease. Among the extraintestinal features of CD, hematologic ones are rather frequent and consist of anemia, thrombocytosis (thrombocytopenia also, but rare), thrombotic or hemorrhagic events, IgA deficiency, hyposplenism, and lymphoma. These hematologic alterations can be the sole manifestation of the disease and should prompt for CD testing in a suggestive clinical scenario. Recognition of these atypical, extraintestinal presentations, including hematologic ones, could represent a great opportunity to increase the diagnostic rate of CD, which is currently one of the most underdiagnosed chronic digestive disorders worldwide. In this review, we summarize recent evidence regarding the hematological manifestations of CD, with focus on practical recommendations for clinicians.

Hematologic Manifestations in Celiac Disease-A Practical Review

Celiac disease (CD) is a systemic autoimmune disease driven by gluten-ingestion in genetically predisposed individuals. Although it primarily affects the small bowel, CD can also involve other organs and manifest as an extraintestinal disease. Among the extraintestinal features of CD, hematologic ones are rather frequent and consist of anemia, thrombocytosis (thrombocytopenia also, but rare), thrombotic or hemorrhagic events, IgA deficiency, hyposplenism, and lymphoma. These hematologic alterations can be the sole manifestation of the disease and should prompt for CD testing in a suggestive clinical scenario. Recognition of these atypical, extraintestinal presentations, including hematologic ones, could represent a great opportunity to increase the diagnostic rate of CD, which is currently one of the most underdiagnosed chronic digestive disorders worldwide. In this review, we summarize recent evidence regarding the hematological manifestations of CD, with focus on practical recommendations for clinicians.

Micronutrient Deficiencies Are Common in Contemporary Celiac Disease Despite Lack of Overt Malabsorption Symptoms

OBJECTIVE

To evaluate micronutrient deficiencies in a contemporary cohort of adult patients with newly diagnosed celiac disease (CD).

PATIENTS AND METHODS

This is a retrospective study of prospective adults newly diagnosed with CD from January 1, 2000, through October 31, 2014, at Mayo Clinic. Micronutrient data were collected for tissue transglutaminase IgA, zinc, 25-hydroxy vitamin D, ferritin, albumin, copper, vitamin B₁₂, and serum folate. Data were analyzed for absolute number of deficiencies and associations with age, sex, body mass index, presenting symptoms, and tissue transglutaminase IgA; each deficiency was assessed using logistic regression. Deficiencies were compared with age- and sex-matched controls from the National Health and Nutrition Examination Survey.

RESULTS

In total, 309 patients with CD (196 women and 113 men; mean age, 46.1±15.1 years; mean body mass index, 25.9 kg/m²) were included. Weight loss was seen in only 25.2% (78/309) of patients. Zinc was deficient in 59.4% (126/212) of patients with CD compared with 33.2% (205/618) of controls (P<.001). Albumin was low in 19.7% (24/122) compared with 1.1% of controls (P<.001). Copper was low in 6.4% (13/204) compared with 2.1% (13/618) of controls (P=.003). Vitamin B₁₂ was low in 5.3% (13/244) compared with 1.8% (11/618) of controls (P=.004). Folate was low in 3.6% (6/159) compared with 0.3% (2/618) of controls (P=.002). 25-Hydroxy vitamin D was low in 19.0% (44/213) compared with 18% (111/618) of controls (P=.72). Ferritin was low in 30.8% (66/214) of patients; no NHANES controls were available for comparison for ferritin.

CONCLUSION

Micronutrient deficiencies remain common in adults with CD despite increased nonclassic presentation. This study provides support for micronutrient assessment at the time of CD diagnosis.

Recent advances in celiac disease and refractory celiac disease

Celiac disease (CeD), defined as gluten-induced enteropathy, is a frequent and largely underdiagnosed disease. Diagnosis relies on the detection of highly specific serum IgA anti-transglutaminase auto-antibodies and on the demonstration of duodenal villous atrophy. Treatment necessitates a strict gluten-free diet, which resolves symptoms and enables histological recovery. However, regular follow-up is necessary to assess mucosal healing, which emerges as an important prognostic factor. Recent work on CeD pathogenesis has highlighted how the cross-talk between gluten-specific CD4 + T cells and interleukin-15 can activate cytotoxic intraepithelial lymphocytes and trigger epithelial lesions. Moreover, acquisition by a subset of intraepithelial lymphocytes of somatic gain-of-function mutations in the JAK-STAT pathway was shown to be a decisive step in the progression toward lymphomas complicating CeD, thus opening new therapeutic perspectives for these rare but life-threatening complications.

AGA Clinical Practice Update on Diagnosis and Monitoring of Celiac Disease-Changing Utility of Serology and Histologic Measures: Expert Review

PURPOSE

The purpose of this clinical practice update is to define key modalities in the diagnosis and monitoring of celiac disease (CD) in adults as well as in children and adolescents.

METHODS

The recommendations outlined in this expert review are based on available published evidence, including cohort and case-control studies of the diagnostic process as well as controlled and descriptive studies of disease management. Best Practice Advice 1: Serology is a crucial component of the detection and diagnosis of CD, particularly tissue transglutaminase-immunoglobulin A (TG2-IgA), IgA testing, and less frequently, endomysial IgA testing. Best Practice Advice 2: Thorough histological analysis of duodenal biopsies with Marsh classification, counting of lymphocytes per high-power field, and morphometry is important for diagnosis as well as for differential diagnosis. Best Practice Advice 2a: TG2-IgA, at high levels (> ×10 upper normal limit) is a reliable and accurate test for diagnosing active CD. When such a strongly positive TG2-IgA is combined with a positive endomysial antibody in a second blood sample, the positive predictive value for CD is virtually 100%. In adults, esophagogastroduodenoscopy (EGD) and duodenal biopsies may then be performed for purposes of differential diagnosis. Best Practice Advice 3: IgA deficiency is an infrequent but important explanation for why patients with CD may be negative on IgA isotype testing despite strong suspicion. Measuring total IgA levels, IgG deamidated gliadin antibody tests, and TG2-IgG testing in that circumstance is recommended. Best Practice Advice 4: IgG isotype testing for TG2 antibody is not specific in the absence of IgA deficiency. Best Practice Advice 5: In patients found to have CD first by intestinal biopsies, celiac-specific serology should be undertaken as a confirmatory test before initiation of a gluten-free diet (GFD). Best Practice Advice 6: In patients in whom CD is strongly suspected in the face of negative biopsies, TG2-IgA should still be performed and, if positive, repeat biopsies might be considered either at that time or sometime in the future. Best Practice Advice 7: Reduction or avoidance of gluten before diagnostic testing is discouraged, as it may reduce the sensitivity of both serology and biopsy testing. Best Practice Advice 8: When patients have already started on a GFD before diagnosis, we suggest that the patient go back on a normal diet with 3 slices of wheat bread daily preferably for 1 to 3 months before repeat determination of TG2-IgA. Best Practice Advice 9: Determination of HLA-DQ2/DQ8 has a limited role in the diagnosis of CD. Its value is largely related to its negative predictive value to rule out CD in patients who are seronegative in the face of histologic changes, in patients who did not have serologic confirmation at the time of diagnosis, and in those patients with a historic diagnosis of CD; especially as very young children before the introduction of celiac-specific serology.

MANAGEMENT

Best Practice Advice 10: Celiac serology has a guarded role in the detection of continued intestinal injury, in particular as to sensitivity, as negative serology in a treated patient does not guarantee that the intestinal mucosa has healed. Persistently positive serology usually indicates ongoing intestinal damage and gluten exposure. Follow-up serology should be performed 6 and 12 months after diagnosis, and yearly thereafter. Best Practice Advice 11: Patients with persistent or relapsing symptoms, without other obvious explanations for those symptoms, should undergo endoscopic biopsies to determine healing even in the presence of negative TG2-IgA.

Management of celiac disease in daily clinical practice

Celiac disease (CD) is the most common autoimmune enteropathy worldwide. In CD, dietary gluten triggers a T cell driven small intestinal inflammation in a subset of genetically predisposed subjects, expressing the HLA DQ2 and/or DQ8 genes on their antigen presenting cells. HLA DQ2/DQ8 can bind gluten peptides after their prior modification by the CD autoantigen, tissue transglutaminase (TG2). This process leads to the activation of gluten reactive T cells, small bowel villous atrophy, crypt hyperplasia and intraepithelial lymphocytosis, the histological hallmarks of CD. The clinical picture of CD is extremely heterogeneous including intestinal (especially diarrhea, abdominal pain, bloating) and extraintestinal (especially associated autoimmune diseases, anemia, osteoporosis) manifestations. The prevalence of CD in most parts of the world is estimated at 1:100-1:150 and its diagnosis is based on the presence of circulating autoantibodies (anti-TG2) and the histological detection of villous atrophy. Treatment is a lifelong gluten free diet but adjunctive therapies are in development. Although CD is a well-characterized disease, it is grossly underdiagnosed, despite the severe consequences of long-term gluten ingestion in CD, such as enhanced autoimmunity, refractory CD and intestinal T cell lymphoma. The aim of the presented review is to provide a clinical guide and to summarize the most recent clinical progress in CD research.

Narrow band imaging evaluation of duodenal villi in patients with and without celiac disease: A prospective study

BACKGROUND

Duodenal biopsies are commonly obtained during esophagogastroduodenoscopy (EGD) but are very often histopathologically normal. Therefore, a more strategic method for evaluating the duodenal mucosa and avoiding unnecessary biopsies is needed.

AIM

To examine the clinical utility of narrow band imaging (NBI) for evaluating duodenal villous morphology.

METHODS

We performed a prospective cohort study of adult patients at Mayo Clinic Rochester from 2013-2014 who were referred for EGD with duodenal biopsies. A staff endoscopist scored, in real-time, the NBI-based appearance of duodenal villi into one of three categories (normal, partial villous atrophy, or complete villous atrophy), captured ≥ 2 representative duodenal NBI images, and obtained mucosal biopsies therein. Images were then scored by an advanced endoscopist and gastroenterology fellow, and biopsies (gold standard) by a pathologist, in a masked fashion using the same three-category classification. Performing endoscopist, advanced endoscopist, and fellow NBI scores were compared to histopathology to calculate performance characteristics [sensitivity, specificity, positive and negative, negative predictive value (NPV), and accuracy]. Inter-rater agreement was assessed with Cohen’s kappa.

RESULTS

112 patients were included. The most common referring indications were dyspepsia (47%), nausea (23%), and suspected celiac disease (14%). Duodenal histopathology scores were: 84% normal, 11% partial atrophy, and 5% complete atrophy. Performing endoscopist NBI scores were 79% normal, 14% partial atrophy, and 6% complete atrophy compared to 91%, 5%, and 4% and 70%, 24%, and 6% for advanced endoscopist and fellow, respectively. NBI performed favorably for all raters, with a notably high (92%-100%) NPV. NBI score agreement was best between performing endoscopist and fellow (κ = 0.65).

CONCLUSION

NBI facilitates accurate, non-invasive evaluation of duodenal villi. Its high NPV renders it especially useful for foregoing biopsies of histopathologically normal duodenal mucosa.

Ultra-short Celiac Disease Is a Distinct and Milder Phenotype of the Disease in Children

BACKGROUND AND AIMS

Approximately 10% of children with celiac disease (CD) have ultra-short celiac disease (USCD), where histological abnormalities are limited to the duodenal bulb. The aim of our retrospective study was to identify clinical and serological characteristics at baseline and at follow-up of children with USCD.

METHODS

All children that were diagnosed with CD in our unit during 7/2010-12/2017, in whom biopsies were taken from duodenal bulb and second part, were included. We compared disease characteristics and course between children with USCD and children with involvement in the second part of the duodenum.

RESULTS

Out of 3740 children who underwent upper gastrointestinal endoscopies, 648 were diagnosed with CD. Seventy-one (11%) of those children had limited involvement in the duodenal bulb. The USCD group included more females (P = 0.021), were older (P = 0.005), had a lower prevalence of diarrhea (P = 0.003), anemia (P = 0.007), anti-tissue transglutaminase (TTG) antibodies count (P < 0.001) at presentation, lower frequency of endoscopic abnormality, lower Marsh score, and a trend toward shorter time to the normalization of anti-TTG antibodies under a gluten-free diet compared to the extensive CD. There were no differences in body mass index or duration of symptoms before diagnosis.

CONCLUSION

Children with USCD presented with a distinct phenotype of milder symptoms, lower celiac serology, and milder endoscopic and histological findings, with a trend toward faster normalization under a gluten-free diet compared to those with extensive CD. Further studies are needed to determine the long-term course and prognosis of USCD.

Efficacy of duodenal bulb biopsy for diagnosis of celiac disease: a systematic review and meta-analysis

Background and study aims  Although duodenal biopsy is considered the "gold standard" for diagnosis of celiac disease, the optimal location of biopsy within the small bowel for diagnosis remains unclear. The primary aim of this study was to perform a structured systematic review and meta-analysis to evaluate the diagnostic utility of endoscopic duodenal bulb biopsy for celiac disease. Patients and methods  Searches of PubMed, EMBASE, Web of Science, and Cochrane Library databases were performed from 2000 through December 2017. Review of titles/abstracts, full review of potentially relevant studies, and data abstraction was performed. Measured outcomes of adult and pediatric patients included location of biopsy, mean number of biopsies performed, and diagnosis of celiac disease as defined by the modified Marsh-Oberhuber classification. Results  A total of 17 studies (n = 4050) were included. Seven studies evaluated adults and 11 studies assessed pediatric populations. Mean age of adults and pediatric patients was 46.70 ± 2.69 and 6.33 ± 1.26 years, respectively. Overall, sampling from the duodenal bulb demonstrated a 5 % (95 % CI 3 - 9; P  < 0.001) increase in the diagnostic yield of celiac disease. When stratified by pediatric and adult populations, duodenal bulb biopsy demonstrated a 4 % (95 % CI: 1 to 9; P  < 0.001) and 8 % (95 % CI: 6 to 10; P  < 0.001) increase in the diagnostic yield of celiac disease. Non-celiac histologic diagnoses including Brunner gland hyperplasia and peptic duodenitis were reported more commonly in the duodenal bulb as compared to the distal duodenum with an increase in diagnostic yield of 4 % (95 % CI 3 - 5; P  < 0.001) and 1 % (95 % CI 1 - 2; P  < 0.001), respectively. Conclusions  Based upon our results, biopsy and histologic examination of duodenal bulb during routine upper endoscopy increases the diagnostic yield of celiac disease.

Clinical guidelines on the diagnosis and treatment of celiac disease in Mexico

Celiac disease, celiac sprue, or gluten-sensitive enteropathy, is a generalized autoimmune disease characterized by chronic inflammation and atrophy of the small bowel mucosa. It is caused by dietary exposure to gluten and affects genetically predisposed individuals. In Mexico, at least 800,000 are estimated to possibly have the disease, prompting the Asociación Mexicana de Gastroenterología to summon a multidisciplinary group of experts to develop the "Clinical guidelines on the diagnosis and treatment of celiac disease in Mexico" and establish recommendations for the medical community, its patients, and the general population. The participating medical professionals were divided into three working groups and were given the selected bibliographic material by the coordinators (ART, LUD, JMRT), who proposed the statements that were discussed and voted upon in three sessions: two voting rounds were carried out electronically and one at a face-to-face meeting. Thirty-nine statements were accepted, and once approved, were developed and revised by the coordinators, and their final version was approved by all the participants. It was emphasized in the document that epidemiology and risk factors associated with celiac disease (first-degree relatives, autoimmune diseases, high-risk populations) in Mexico are similar to those described in other parts of the world. Standards for diagnosing the disease and its appropriate treatment in the Mexican patient were established. The guidelines also highlighted the fact that a strict gluten-free diet is essential only in persons with confirmed celiac disease, and that the role of gluten is still a subject of debate in relation to nonceliac, gluten-sensitive patients.

A prospective study to evaluate the role of duodenal bulb biopsy in the diagnosis of celiac disease

BACKGROUND

Celiac disease (CeD) requires a biopsy from the small intestine to confirm the diagnosis. Conventionally, duodenal bulb (D1) was avoided as a biopsy site due to histological confounding factors at this site. However, sometimes, the bulb mucosa is the only affected site. The aim of the present study was to assess changes in duodenal bulb histology and compare it to distal duodenal histology and to analyze whether the addition of duodenal bulb biopsy increases the diagnostic yield of the CeD.

METHODS

It was a prospective study comprising of 98 patients of CeD who were symptomatic clinically and had positive anti tissue transglutaminase (tTG) antibody. Endoscopically four mucosal biopsies were taken, two each from the bulb and distal duodenum, and morphology was graded as per modified Marsh grade.

RESULTS

Iron deficiency anemia (40%) was a most common clinical presentation followed by chronic diarrhea (30%). Sixty patients showed same Marsh grade and 38 showed different Marsh grade at both sites. Patients who were showing the difference in the Marsh grade at the two biopsy sites, in place of; descending duodenum showed higher grade in 24 patients while higher mucosal atrophy was documented in the bulb in 14 patients. No patient of CeD had isolated D1 involvement. In eight patients, the correct diagnosis of CeD could be made only because of bulb biopsy.

CONCLUSION

Majority of the patients had no classical symptoms. Different Marsh grade at the two biopsy sites was documented demonstrating the patchy distribution of CeD. Combining biopsy from both bulb and descending duodenum maximizes the diagnostic yield of the CeD.

Coeliac disease

Coeliac disease occurs in about 1% of people in most populations. Diagnosis rates are increasing, and this seems to be due to a true rise in incidence rather than increased awareness and detection. Coeliac disease develops in genetically susceptible individuals who, in response to unknown environmental factors, develop an immune response that is subsequently triggered by the ingestion of gluten. The disease has many clinical manifestations, ranging from severe malabsorption to minimally symptomatic or non-symptomatic presentations. Diagnosis requires the presence of duodenal villous atrophy, and most patients have circulating antibodies against tissue transglutaminase; in children, European guidelines allow a diagnosis without a duodenal biopsy provided that strict symptomatic and serological criteria are met. Although a gluten-free diet is an effective treatment in most individuals, a substantial minority develop persistent or recurrent symptoms. Difficulties adhering to a gluten-free diet have led to the development of non-dietary therapies, several of which are undergoing trials in human beings.

Celiac Disease and Other Causes of Duodenitis

CONTEXT

- Patients who receive an upper gastrointestinal endoscopic examination frequently have biopsies taken from the duodenum. Accurate interpretation of duodenal biopsies is essential for patient care. Celiac disease is a common clinical concern, but pathologists need to be aware of other conditions of the duodenum that mimic celiac disease.

OBJECTIVE

- To review the normal histologic features of duodenal mucosa and describe the clinical and histologic findings in celiac disease and its mimics, listing the differentiating features of biopsies with villous atrophy and epithelial lymphocytosis.

DATA SOURCES

- The study comprises a literature review of pertinent publications as of November 30, 2016.

CONCLUSIONS

- Celiac disease is a common cause of abnormal duodenal histology. However, many of the histologic features found in the duodenal biopsy of patients with celiac disease are also present in other conditions that affect the small bowel. Diagnostic precision may be enhanced by obtaining a careful patient history and by ancillary laboratory testing, particularly for the presence of antitissue transglutaminase antibodies.

Coeliac disease: to biopsy or not?

Coeliac disease is increasingly recognized as a global problem in both children and adults. Traditionally, the findings of characteristic changes of villous atrophy and increased intraepithelial lymphocytosis identified in duodenal biopsy samples taken during upper gastrointestinal endoscopy have been required for diagnosis. Although biopsies remain advised as necessary for the diagnosis of coeliac disease in adults, European guidelines for children provide a biopsy-sparing diagnostic pathway. This approach has been enabled by the high specificity and sensitivity of serological testing. However, these guidelines are not universally accepted. In this Perspective, we discuss the pros and cons of a biopsy-avoiding pathway for the diagnosis of coeliac disease, especially in this current era of the call for more biopsies, even from the duodenal bulb, in the diagnosis of coeliac disease. In addition, a contrast between paediatric and adult guidelines is presented.

Celiac Disease: A Review of Current Concepts in Pathogenesis, Prevention, and Novel Therapies

Our understanding of celiac disease and how it develops has evolved significantly over the last half century. Although traditionally viewed as a pediatric illness characterized by malabsorption, it is now better seen as an immune illness with systemic manifestations affecting all ages. Population studies reveal this global disease is common and, in many countries, increasing in prevalence. These studies underscore the importance of specific HLA susceptibility genes and gluten consumption in disease development and suggest that other genetic and environmental factors could also play a role. The emerging data on viral and bacterial microbe-host interactions and their alterations in celiac disease provides a plausible mechanism linking environmental risk and disease development. Although the inflammatory lesion of celiac disease is complex, the strong HLA association highlights a central role for pathogenic T cells responding to select gluten peptides that have now been defined for the most common genetic form of celiac disease. What remains less understood is how loss of tolerance to gluten occurs. New insights into celiac disease are now providing opportunities to intervene in its development, course, diagnosis, and treatment.

Practical Approach to the Flattened Duodenal Biopsy

Celiac disease features duodenal intraepithelial lymphocytosis with or without villous atrophy. Lymphocytosis without villous atrophy will be proven to represent celiac disease in 10% to 20% of cases. The differential diagnosis is broad: Helicobacter pylori gastritis, NSAID injury and bacterial overgrowth are considerations. Lymphocytosis with villous atrophy is very likely to be celiac disease, but there are mimics to consider, including collagenous sprue, tropical sprue, drug injury, and common variable immunodeficiency. Histologic clues to a diagnosis other than celiac disease include paucity of plasma cells, excess of neutrophils, granulomas, and relative paucity of intraepithelial lymphocytes.