Villous tip intraepithelial lymphocytes as markers of early-stage coeliac disease

Clinical Data Do Not Reliably Predict Duodenal Histology at Follow-up in Celiac Disease: A 13 Center Correlative Study

Validated nonbiopsy methods to assure duodenal mucosal healing in celiac disease are lacking, yet ongoing mucosal injury is associated with anemia, osteoporosis, and lymphoma. Most providers utilize clinical data as surrogates of mucosal status to avoid additional esophagogastroduodenoscopy. The reliability of such surrogates to predict mucosal recovery has been incompletely evaluated. The aim of this study was to rigorously assess patterns of histologic mucosal recovery at follow-up in celiac disease and to correlate findings with clinical data. Gastrointestinal pathologists from 13 centers evaluated initial and follow-up duodenal biopsies from 181 celiac disease patients. Marsh scores and intraepithelial lymphocytes (IELs)/100 enterocytes were assessed blindly. Histology at follow-up was correlated with symptoms, immunoglobulin A anti-tissue transglutaminase titers and gluten-free diet adherence. Fifty-six/181 (31%) patients had persistent villous blunting and 46/181 (25%) patients had just persistently elevated IELs at follow-up, with only 79/181 (44%) patients having complete histologic remission. IEL normalization (82/181; 45%) lagged villous recovery (125/181;69%). In a minority of patients, villous blunting was limited to proximal duodenal biopsies. No correlation was found between Marsh scores and symptoms, normalization of immunoglobulin A anti-tissue transglutaminase serology, or diet adherence. Children showed greater recovery of Marsh score ( P <0.001) and IELs ( P <0.01) than adults. Persistent mucosal injury is common in celiac disease, with discordant villous/IEL normalization. Pathologist awareness of expected findings in celiac disease follow-up biopsies, including their frequent lack of correlation with clinical data, is important for patient management, and has implications for eligibility criteria for therapeutics currently in development.

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.

Immunohistochemical analysis of intestinal biopsies in individuals with celiac disease

Background and Aims

The immunohistochemical application of CD3 (T lymphocytes) and CD20 (B lymphocytes) markers in duodenal biopsy can facilitate the detection of the number and distribution of intraepithelial lymphocytes along the villi, which is regarded as a key factor for accurate diagnosis of celiac disease. This study aims at finding a relationship between CD3 and CD20 immunohistochemical and histopathological alterations of celiac disease, and at investigating whether the application of those immunohistochemical stainings would improve the detection of lymphocytosis within the epithelium and add advantages to celiac disease diagnosis.

Methods

Biopsies were obtained from 100 individuals and stained with hematoxylin and eosin (H&E). They were then evaluated according to the Marsh classification. After that, staining for CD3 and CD20 was individually done and assessed.

Results

The overall mean intraepithelial lymphocyte count per 100 enterocytes for H&E was 23.1 (95% confidence interval [CI] = 19.52–26.68), and for immunohistochemistry by CD3 and CD20 was 27.84 (95% CI = 24.31–31.38). The difference was highly significant, P = 0.001. The expression of CD3 immunohistochemically was as follows: Less‐than‐half staining pattern was reported in 16% cases, and half staining pattern was seen in 26%, while most cases 58% had more than half staining pattern. This discovery was consistent with the histological classification of March III among most cases. The expression of CD20 immunohistochemically was as follows: mild crypt involvement was observed in 16% of cases, while moderate crypt involvement and intense crypt involvement were seen in 43% and 41% of cases, respectively.

Critical diagnoses in paediatric gastrointestinal diseases

Gastrointestinal biopsies represent an increasing proportion of the paediatric pathologist's workload, an increase fundamentally due to an expansion of the understanding of the basic clinical, molecular, genetic, and histopathological features of paediatric gastrointestinal disorders. The histological interpretation of endoscopically retrieved gastrointestinal biopsies in children requires a unique set of diagnostic expertise and detailed knowledge of various gastrointestinal disorders that have a predilection for the paediatric population. This article's major role is to highlight the unique problems inherent to paediatric gastrointestinal disorders that require immediate communication with the paediatric surgeon or the gastroenterologist. For this, we tried to cover the most important diseases that a paediatric pathologist might encounter in daily practice. Some of these diseases are relatively rare, such as microvillous inclusion disease and tufting enteropathy, but some are more common such as eosinophilic disorders and inflammatory bowel disease. Awareness of the histopathological features of these diseases, particularly those that are relatively uncommon, is crucial to spare the patient a lengthy and costly evaluation. We made a particular effort to abundantly reference this article should the reader wish to expand on the content of any section.

Frontiers in Celiac Disease: Where Autoimmunity and Environment Meet

Celiac disease is a chronic, immune-mediated enteropathy driven by dietary gluten found in genetically susceptible hosts. It has a worldwide distribution, is one of the most common autoimmune disorders globally, and is the only autoimmune condition for which the trigger is known. Despite advances in characterizing mechanisms of disease, gaps in understanding of celiac disease pathogenesis remain. A "frontier" concept is considering what moves an HLA-DQ2 or DQ8-positive individual from asymptomatic gluten tolerance to celiac disease manifestation. In this arena, environmental triggers, including age at the time of initial gluten exposure, the occurrence of usual childhood viral infections, and microbiome alterations have emerged as key events in triggering the symptomatic disease. Pathologists play a major role in frontier aspects of celiac disease. This includes the discovery that duodenal mucosal histology in follow-up biopsies does not correlate with ongoing patient symptoms, antitissue transglutaminase antibody titers and diet adherence in celiac disease patients. Further, in light of recent evidence that the detection of monoclonal T-cell populations in formalin-fixed biopsies is not specific for type II refractory celiac disease, pathologists should resist performing such analyses until common causes of "apparent" refractoriness are excluded. The promise of therapies in celiac disease has led to clinical trials targeting many steps in the inflammatory cascade, which depend upon a pathologist's confirmation of the initial diagnosis and evaluation of responses to therapies. As pathologists continue to be active participants in celiac disease research, partnering with other stakeholders, we will continue to impact this important autoimmune disease.

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.

Morphological evaluation of bulb and distal duodenal biopsies in pediatric celiac disease with clinical and serological correlation

Background and Aims

An early correct diagnosis of celiac disease (CD) is fundamental to reversal of symptoms and prevention of complications in pediatric patients. Our aim was to evaluate the role of duodenal bulb biopsy by studying the degree of mucosal damage in the duodenal bulb (D1) and second part of the duodenum (D2) and correlating the findings with serum IgA anti-tTG levels.

Settings and Design

Pediatric patients (age <18 years) with clinical suspicion of CD and positive IgA anti-tTG titers were consecutively enrolled over a period of one year. Demographic variables, anthropometry, clinical history, laboratory values and endoscopic findings were studied. Endoscopic biopsies obtained from D1 and D2 were evaluated and assigned histopathologic grades that were correlated with serology.

Statistical Analysis Used

Descriptive statistics were employed.

Results

A total of 37 clinically suspected cases of pediatric CD were studied. The mean age was 6.7 years and the M:F ratio was 1:1.3. Thirty-two (32) children had varying degrees of growth impairment. Eight (8) children had only extra-intestinal symptoms. Thirty (30) children were anemic, hypoalbuminemia was seen in five (5) children while transaminitis was seen in two (2) children. IgA anti-tTG >300 U/ml was associated with Marsh-Oberhuber Grade 3 morphology at atleast one site.

Conclusions

Low positive serology values should be confirmed by histopathology. Biopsies should be taken even in the absence of endoscopic abnormality. Additional D1 biopsies placed in a separate container can increase the diagnostic yield.

The role of histopathology in the diagnosis and management of coeliac disease and other malabsorptive conditions

Most absorption of nutrients takes place in the proximal small intestine, and the most common disorders leading to malabsorption are associated with a morphological abnormality in the duodenal mucosa that is appreciable in histological sections of biopsy specimens. Coeliac disease is the most well-known example, causing intraepithelial lymphocytosis, inflammation and villous atrophy in the duodenum. Remarkably similar inflammatory changes can be induced by other processes, including medications, e.g. angiotensin II receptor blockers and immune checkpoint inhibitors, immune dysregulation disorders, e.g. common variable immunodeficiency and autoimmune enteropathy, infections, collagenous sprue, and tropical sprue. However, there are often subtle histological differences from coeliac disease in the type of inflammatory infiltrate, the presence of crypt apoptosis, and the extent and type of inflammation beyond the duodenum. The clinical setting and serological investigation usually allow diagnostic separation, but some cases remain challenging. Histopathology is also important in assessing the response to treatment, such as the change in villous architecture caused by a gluten-free diet, or the response to cessation of a potentially causative medication. This review examines the practical role that histopathology of duodenal biopsy specimens plays in the assessment and management of inflammatory malabsorptive processes of the proximal small intestine, with a particular emphasis on coeliac disease.

Coeliac Disease Pathogenesis: The Uncertainties of a Well-Known Immune Mediated Disorder

Coeliac disease is a common small bowel enteropathy arising in genetically predisposed individuals and caused by ingestion of gluten in the diet. Great advances have been made in understanding the role of the adaptive immune system in response to gluten peptides. Despite detailed knowledge of these adaptive immune mechanisms, the complete series of pathogenic events responsible for development of the tissue lesion remains less certain. This review contributes to the field by discussing additional mechanisms which may also contribute to pathogenesis. These include the production of cytokines such as interleukin-15 by intestinal epithelial cells and local antigen presenting cells as a pivotal event in the disease process. A subset of unconventional T cells called gamma/delta T cells are also persistently expanded in the coeliac disease (CD) small intestinal epithelium and recent analysis has shown that these cells contribute to pathogenic inflammation. Other unconventional T cell subsets may play a local immunoregulatory role and require further study. It has also been suggested that, in addition to activation of pathogenic T helper cells by gluten peptides, other peptides may directly interact with the intestinal mucosa, further contributing to the disease process. We also discuss how myofibroblasts, a major source of tissue transglutaminase and metalloproteases, may play a key role in intestinal tissue remodeling. Contribution of each of these factors to pathogenesis is discussed to enhance our view of this complex disorder and to contribute to a wider understanding of chronic immune-mediated disease.

Non-immunological biomarkers for assessment of villous abnormalities in patients with celiac disease

BACKGROUND AND AIM

Demonstration of villous abnormalities is an essential component of diagnosis of celiac disease (CeD) that requires duodenal biopsies. There is a need for non-invasive biomarker(s) that can predict the presence of villous abnormalities.

METHODS

Levels of plasma citrulline, plasma intestinal fatty acid binding protein (I-FABP), and serum regenerating gene 1α (Reg1α) were estimated in treatment naïve patients with CeD and controls. The levels of these biomarkers and their cyclical pattern were validated in a predicted model of enteropathy. Optimum diagnostic cut-off values were derived, and the results were further validated in a prospective validation cohort.

RESULTS

While level of plasma citrulline was significantly lower, the levels of plasma I-FABP and serum Reg1α were significantly higher in patients with CeD (n = 131) in comparison with healthy (n = 216) and disease controls (n = 133), and their levels reversed after a gluten-free diet (GFD). In the model of predicted enteropathy (n = 70), a sequential decrease and then increase in the level of plasma citrulline was observed; such a sequential change was not observed with I-FABP and Reg1α. The diagnostic accuracy for prediction of presence of villous abnormality was 89% and 78% if citrulline level was  ≤ 30 μM/L and I-FABP levels were ≥ 1100 pg/mL, respectively. The results were validated in a prospective validation cohort (n = 104) with a sensitivity and specificity of 79.5% and 83.1%, respectively, for predicting villous abnormalities of modified Marsh grade > 2 at calculated cut-off values of citrulline and I-FABP.

CONCLUSIONS

Plasma citrulline  ≤ 30 μM/L is the most consistent, highly reproducible non-invasive biomarker that can predict the presence of villous abnormality and has the potential for avoiding duodenal biopsies in 78% patients suspected to have CeD.

Prevalence and diagnostic outcomes of children with duodenal lesions and negative celiac serology

BACKGROUND

Celiac disease diagnostics begin by measuring autoantibodies, which may fail to identify seronegative patients. Duodenal lesion in the absence of antibodies is scarcely studied, especially in children.

AIMS

To investigate the prevalence and diagnostic outcomes of children with seronegative duodenal lesion in two countries with different disease profiles.

METHODS

Medical data, including the results of histology and transglutaminase (tTGab) and endomysium (EmA) antibody measurements were collected from 1172 Finnish and 264 Romanian children with systematic duodenal sampling. Database of 509 Finnish children with celiac disease was examined to identify earlier seronegative patients.

RESULTS

Celiac disease was diagnosed in 307 Finnish and 83 Romanian children in the endoscopy cohorts. No seronegative patients were found among 899 celiac disease patients, although some were only tTGab or EmA positive. Non-celiac duodenal lesion was detected in eight Finnish and 32 Romanian children, their most common diagnoses being inflammatory bowel disease and infections, respectively. Six children with morphological lesion received no diagnosis. None of them developed celiac disease during a follow-up of 3-11 years.

CONCLUSION

Pediatric seronegative celiac disease is exceptional in the era of modern autoantibodies. Other reasons for duodenal lesion should therefore be sought, bearing in mind possible differences across countries.

Clinical Insignficance of Monoclonal T-Cell Populations and Duodenal Intraepithelial T-Cell Phenotypes in Celiac and Nonceliac Patients

Refractory celiac disease (RCD) is a rare condition, usually managed at specialized centers. However, gastroenterologists and pathologists in general practices are often the first to consider a diagnosis of RCD in celiac patients with persistent symptoms. The distinction between type I and type II RCD is crucial as patients with RCD II have a shortened life expectancy. The diagnosis of RCD II requires the demonstration of abnormal intraepithelial lymphocytes and/or monoclonal T-cell populations in duodenal biopsies, typically assessed in formalin-fixed paraffin-embedded tissue. We investigated the clinical significance of T-cell receptor gene rearrangements and CD3/CD8 staining in formalin-fixed paraffin-embedded biopsies from 32 patients with RCD I (4), RCD II (3), newly diagnosed celiac disease (CD) (10), established CD patients with follow-up biopsies (10), and Helicobacter pylori-associated lymphocytosis (5). Clonal T-cell populations were present in all lymphocytosis groups but not in normal controls. No difference in the frequency of clonal populations or persistence of identical clones was found between RCD I and II patients. The degree of villous blunting did not correlate with clonal status in any group. No difference in the number of CD3/CD8-positive intraepithelial lymphocytes per 100 enterocytes was found between groups. We suggest that clonal evaluation of T cells should not be employed routinely in the evaluation of CD patients with persistent symptoms until common causes of "apparent refractoriness" have been excluded. In addition, lymphocyte phenotyping and T-cell clonal analysis appear to be insufficient as stand-alone tests to reliably distinguish RCD I and II.

The Challenge of Treatment in Potential Celiac Disease

Potential celiac disease (PCD) is defined by the presence of positive serum antibodies, HLA-DQ2/DQ8 haplotypes, and a normal small intestinal mucosa (Marsh grade 0-1). This condition occurs in one-fifth of celiac disease (CD) patients and usually represents a clinical challenge. We reviewed genetic, histologic, and clinical features of this specific condition by performing a systematic search on MEDLINE, Embase, and Scholar database. Accordingly, we identified different genetic features in patients with PCD compared to the classical forms. Frequently, signs of inflammation (deposits of immunoglobulin A (IgA) and/or increased number of intraepithelial lymphocytes) can be clearly identify in the mucosa of PCD patients after an accurate histological assessment. Finally, the main challenge is represented by the treatment: the gluten-free diet should be considered only in the presence of gluten-dependent symptoms in both children and adults. What is known: (i) potential celiac disease (PCD) occurs in one-fifth of all celiac diseases (CD), and (ii) despite the absence of classical lesions, clear signs of inflammation are often detectable. What is new: (i) patients with PCD show different genetic features, and (ii) the presence of gluten-dependent symptoms is the main determinant to initiate the gluten-free diet, after a complete diagnostic work-up.

Celiac Disease: Updates on Pathology and Differential Diagnosis

Celiac disease is a gluten-triggered immune-mediated disorder, characterized by inflammation of the enteric mucosa following lymphocytic infiltration and eventually resulting in villous blunting. There have been many developments in refining diagnostic laboratory tests for celiac disease in the last decade. Biopsy-sparing diagnostic guidelines have been proposed and validated in a few recent prospective studies. However, despite these developments, histologic evaluation of duodenal mucosa remains one of the most essential diagnostic tools as it helps in the diagnosis of celiac disease in individuals who do not fulfill the biopsy-sparing diagnostic criteria and in those not responding to a gluten-free diet. Histologic evaluation also allows for the assessment of mucosal recovery after treatment and in the identification of concurrent intestinal diseases. Therefore, pathologists should be familiar with the histologic spectrum of celiac disease and need to be aware of other disorders with similar symptoms and histopathology that may mimic celiac disease. This review aims to provide pathologists with updates on celiac laboratory testing, biopsy-sparing diagnostic criteria, histopathology, complications, and differential diagnoses of celiac disease.

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.

Progression of Celiac Disease in Children With Antibodies Against Tissue Transglutaminase and Normal Duodenal Architecture

BACKGROUND & AIMS

Potential celiac disease is characterized by positive results from serologic tests for tissue transglutaminase antibodies (anti-TG2) but normal duodenal architecture (Marsh stages 0-1). There is controversy over the best way to manage these patients. We investigated risk factors associated with the development of villous atrophy in children with potential celiac disease.

METHODS

We performed a prospective study of 280 children (ages 2-18 years) in Italy with suspected celiac disease, followed for up to 12 years (range, 18-150 months; median 60 months). The subjects had 2 consecutive positive results from tests for anti-TG2, tested positive for the endomysial antibody (anti-EMA), had total serum levels of immunoglobulin A in the normal range, normal duodenal architecture (Marsh stages 0-1) in 5 biopsies, and HLA DQ2- or DQ8-positive haplotypes. The children underwent serologic tests and clinical analyses every 6 months and a small bowel biopsy was taken every 2 years. A total of 210 patients of the original cohort were assessed at the 9-year follow-up evaluation. We performed multivariate analyses of clinical, genetic, and histologic data to identify factors associated with progression to villous atrophy.

RESULTS

During the follow-up period, 42 (15%) of 280 children developed villous atrophy, whereas 89 (32%) children no longer tested positive for anti-TG2 or anti-EMA. The cumulative incidence of progression to villous atrophy was 43% at 12 years. In multivariate analysis, the baseline factors most strongly associated with development of villous atrophy were numbers of γδ intraepithelial lymphocyte cells followed by age and homozygosity for the HLA DQB1*02. In discriminant analysis, these baseline factors identified 80% of the children who developed baseline atrophy.

CONCLUSIONS

In a long-term study of 280 children with suspected celiac disease (based on anti-TG2 and anti-EMA) on gluten-containing diets, the cumulative incidence of progression to villous atrophy was 43% over a 12-year period. We identified factors that can be used to identify children at highest risk for villous atrophy. This approach might be used to determine whether children with suspected celiac disease should immediately start a gluten-free diet or be monitored on their regular diet.

Quantitative histology-based classification system for assessment of the intestinal mucosal histological changes in patients with celiac disease

Background/Aims

The existing histological classifications for the interpretation of small intestinal biopsies are based on qualitative parameters with high intraobserver and interobserver variations. We have developed and propose a quantitative histological classification system for the assessment of intestinal mucosal biopsies.

Methods

We performed a computer-assisted quantitative histological assessment of digital images of duodenal biopsies from 137 controls and 124 patients with celiac disease (CeD) (derivation cohort). From the receiver-operating curve analysis, followed by multivariate and logistic regression analyses, we identified parameters for differentiating control biopsies from those of the patients with CeD. We repeated the quantitative histological analysis in a validation cohort (105 controls and 120 patients with CeD). On the basis of the results, we propose a quantitative histological classification system. The new classification was compared with the existing histological classifications for interobserver and intraobserver agreements by a group of qualified pathologists.

Results

Among the histological parameters, intraepithelial lymphocyte count of ≥25/100 epithelial cells, adjusted villous height fold change of ≤0.7, and crypt depth-to-villous height ratio of ≥0.5 showed good discriminative power between the mucosal biopsies from the patients with CeD and those from the controls, with 90.3% sensitivity, 93.5% specificity, and 96.2% area under the curve. Among the existing histological classifications, our quantitative histological classification showed the highest intraobserver (69.7%–85.03%) and interobserver (24.6%–71.5%) agreements.

Conclusions

Quantitative assessment increases the reliability of the histological assessment of mucosal biopsies in patients with CeD. Such a classification system may be used for clinical trials in patients with CeD.

Epithelial MHC Class II Expression and Its Role in Antigen Presentation in the Gastrointestinal and Respiratory Tracts

As the primary barrier between an organism and its environment, epithelial cells are well-positioned to regulate tolerance while preserving immunity against pathogens. Class II major histocompatibility complex molecules (MHC class II) are highly expressed on the surface of epithelial cells (ECs) in both the lung and intestine, although the functional consequences of this expression are not fully understood. Here, we summarize current information regarding the interactions that regulate the expression of EC MHC class II in health and disease. We then evaluate the potential role of EC as non-professional antigen presenting cells. Finally, we explore future areas of study and the potential contribution of epithelial surfaces to gut-lung crosstalk.

Discriminant value of IEL counts and distribution pattern through the spectrum of gluten sensitivity: a simple diagnostic approach

Intraepithelial lymphocytosis (IELosis) with or without villous abnormality is a characteristic feature of gluten sensitivity (GS) including celiac disease (CD) and non-celiac-GS, although various conditions may also be associated with IELosis. In order to distinguish GS from the other causes of IELosis, a threshold for IEL counts is necessary. We aimed to determine a cut-off value for IELs and monitor its value in the spectrum of GS in a large cohort. For this purpose, the duodenal biopsies from four groups of individuals including Types 1 (n = 88) and 3 (n = 92) CD, non-CD IELosis (n = 112), and control (n = 82) cases, all strictly defined by their clinical, laboratory, and serologic features, were evaluated. The number of IELs/100 enterocytes and their distribution pattern on H&E- and CD3-immunostained sections were assessed for each group. Kruskal-Wallis test and ROC curve analysis for discriminant value were employed for statistics. The IEL counts showed an increasing trend through the spectrum of mucosal pathology including controls (12.06; 21.40), non-CD IELosis (28.62; 39.46), Type 1 CD (49.27; 60.15), and Type 3 CD (58.53; 71.74) both on H&E- and CD3-immunostained sections, respectively (p < 0.001). ROC analysis revealed 20.5 on H&E and 28.5 on CD3 as the IEL cut-off values with a sensitivity of 95.9 and 87.7% and a specificity of 98.8% and 93.9%, respectively, for controls. IELs showed a diffuse distribution pattern per biopsy piece and per villus (90.9%, 100%, respectively) in nearly all of Type 1 CD cases (p < 0.001). An IEL cut-off value of 20.5 on H&E together with a diffuse distribution pattern seem to be the most discriminant features for the diagnosis of CD, even for the milder forms of the disease.

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.

Intestinal epithelium, intraepithelial lymphocytes and the gut microbiota - Key players in the pathogenesis of celiac disease

Celiac disease (CD) is a chronic immune-mediated disorder triggered by the ingestion of gluten in genetically predisposed individuals. Before activating the immune system, gluten peptides are transferred by the epithelial barrier to the mucosal lamina propria, where they are deamidated by intestinal tissue transglutaminase 2. As a result, they strongly bind to human leucocyte antigens (HLAs), especially HLA-DQ2 and HLA-DQ8, expressed on antigen-presenting cells. This induces an inflammatory response, which results in small bowel enteropathy. Although gluten is the main external trigger activating both innate and adaptive (specific) immunity, its presence in the intestinal lumen does not fully explain CD pathogenesis. It has been hypothesized that an early disruption of the gut barrier in genetically susceptible individuals, which would result in an increased intestinal permeability, could precede the onset of gluten-induced immune events. The intestinal barrier is a complex functional structure, whose functioning is dependent on intestinal microbiota homeostasis, epithelial layer integrity, and the gut-associated lymphoid tissue with its intraepithelial lymphocytes (IELs). The aim of this paper was to review the current literature and summarize the role of the gut microbiota, epithelial cells and their intercellular junctions, and IELs in CD development.

Gluten-related disorders: certainties, questions and doubts

In the last decade, the ingestion of gluten, a heterogeneous complex of proteins present in wheat, rice, barley and probably in oats, has been associated with clinical disorders, such as celiac disease, wheat allergy and recently to non-celiac gluten sensitivity or wheat intolerance syndrome. Gluten-related disorders, which are becoming epidemiologically relevant with an estimated global prevalence of about 5%, require the exclusion of gluten from the diet. For the past 5 years, an important shift in the availability of gluten-free products, together with increased consumption in the general population, has been recorded and is estimated to be about 12-25%. Many people follow a self-prescribed gluten-free diet, despite the fact that the majority have not first been previously excluded, or confirmed, as having gluten disorders. They rely on claims that a gluten-free diet improves general health. In this review, we provide an overview of the clinical disorders related to gluten or wheat ingestion, pointing out the current certainties, open questions, possible answers and several doubts in the management of these conditions. KEY MESSAGE Incidence of gluten-related disorders is increased in the last decade and self-diagnosis is frequent with inappropriate starting of a gluten-free diet. Gluten and wheat are considered as the most important triggers to coeliac disease, wheat allergy and non-celiac gluten sensitivity. Pediatricians, allergologist and gastroenterologist are involved in the management of these conditions and appropriate diagnostic protocols are required.

Morphologic Spectrum of Duodenal Biopsies in Malabsorption: A Study from Southern India

INTRODUCTION

Duodenal endoscopic biopsy is a common investigation for various non-neoplastic conditions. Malabsorption is a common indication for duodenal biopsy in our setting.

AIM

Our study was undertaken to study the morphologic spectrum of non-neoplastic conditions of duodenum emphasizing on Intraepithelial Lymphocytes (IELs) and to have a clinico-pathologic correlation.

MATERIALS AND METHODS

This was a prospective descriptive study. Duodenal biopsies from 101 patients with symptoms of malabsorption were studied according to inclusion and exclusion criteria. Informed written consent was taken. Clinical, laboratory, endoscopic, and serological parameters were collected wherever available. Histomorphological parameters were studied on Haematoxylin and Eosin (H&E) stained sections. Intraepithelial lymphocyte counts were done on CD3, CD4 and CD8 Immunohistochemical (IHC) stained sections and correlated.

RESULTS

We studied 101 duodenal biopsies. Our spectrum included 16 patients of celiac disease (CD) (15.8%), 15 autoimmune duodenitis (14%), 13 nutritional deficiency associated duodenitis (12.8%), five infectious duodenitis (5%) and 41 patients of non-specific duodenitis (40.6%) and 10.9% miscellaneous causes of duodenitis. Villous crypt architecture, IEL counts; villous tip IEL counts were statistically significant between CD and other disease groups.

CONCLUSION

A constellation of clinical, serological, endoscopic and histopathologic features is essential in diagnosing CD and autoimmune duodenitis. Biopsy is also a useful tool in diagnosing infectious duodenitis that are missed in other investigations.

Intraepithelial lymphocyte immunophenotype: a useful tool in the diagnosis of celiac disease

According to new ESPGHAN guidelines, gluten challenge is considered necessary when there is doubt about the initial diagnosis of celiac disease (CD). The main aim of this study was to quantify intraepithelial lymphocyte (IEL) immunophenotype on celiac patients on gluten-containing diet (GCD) compared to those on gluten-free diet (GFD). Another aim was to evaluate the clinical utility of IELs in the CD diagnosis, especially in selected patients on GFD where diagnostic uncertainty remains. IEL immunophenotype (TCRγδ and NK-like IELs) were studied by flow cytometry in 111 children with CD (81 children with CD on GCD and 30 celiac patients on GFD) and a control group (10 children). Duration of GFD was 5.4 ± 1.6 years. TCRγδ IELs in celiac patients receiving a GCD or GFD were significantly higher (p < 0.001) than in the control group. NK-like IELs in patients receiving a GCD or GFD were significantly lower than in the control group (p < 0.001). We observed a permanent decrease of NK-like IELs and an increment of TCRγδ IELs after following an adequate establishment and compliance of a long-term GFD in celiac patients. Recognition of IELs changes in the intestinal mucosa on celiac patients after long-term establishment of a GFD could constitute a useful tool for CD diagnosis in various situations: in which there is doubt about the initial diagnosis and repeat biopsy is necessary (avoiding the need of gluten challenges), and in those patients with symptoms/signs suggestive of CD who maintain a low gluten diet.

Flow cytometry of duodenal intraepithelial lymphocytes improves diagnosis of celiac disease in difficult cases

BACKGROUND

Diagnosis of celiac disease is difficult when the combined results of serology and histology are inconclusive. Studies using flow cytometry of intraepithelial lymphocytes (IELs) have found that celiac patients have increased numbers of γδ IELs, along with a decrease in CD3-CD103 + IELs.

OBJECTIVE

The objective of this article is to assess the role of flow cytometric analysis of IELs in the diagnosis of celiac disease in difficult cases.

METHODS

A total of 312 patients with suspicion of celiac disease were included in the study. Duodenal biopsy samples were used for histological assessment and for flow cytometric analysis of IELs.

RESULTS

In 46 out of 312 cases (14.7%) the combination of serology and histology did not allow the confirmation or exclusion of celiac disease. HLA typing had been performed in 42 of these difficult cases. Taking into account HLA typing and the response to a gluten-free diet, celiac disease was excluded in 30 of these cases and confirmed in the remaining 12. Flow cytometric analysis of IELs allowed a correct diagnosis in 39 out of 42 difficult cases (92.8%) and had a sensitivity of 91.7% (95% CI: 61.5% to 99.8%) and a specificity of 93.3% (95% CI: 77.9% to 99.2%) for the diagnosis of celiac disease in this setting.

CONCLUSION

Flow cytometric analysis of IELs is useful for the diagnosis of celiac disease in difficult cases.

Revisiting Pathological Criteria for Earlier Diagnosis of Coeliac Disease

OBJECTIVES

The diagnosis of coeliac disease (CD) remains sometimes difficult because the histological criteria are not fully met. The aim of this study was to refine histological diagnostic criteria of CD.

METHODS

One hundred seventy-five duodenal bulb D1 (n = 79) and duodenal D2 (n = 96) biopsies of 96 patients with CD (58 girls, mean age 7 years), 135 normal D2 biopsies (69 girls, mean age 12 years), and 64 D2 biopsies of other digestive disorders (DDs) (39 girls, mean age 13 years) obtained from children during a period of 4 years were reviewed.

RESULTS

Interobserver agreement was greater for the classification of Corazza-Villanacci than for Marsh-Oberhuber (κ = 0.812 vs κ = 0.409, respectively). Between 40 and 70 intraepithelial lymphocytes (IELs) per 100 epithelial cells (ECs), 32% of patients were CD, whereas 50% had other DD. Above 70 IELs per 100 EC, 53% were CD, and only 6% had other DD. In CD, IELs were significantly located above EC nuclei compared with other DD, (12 IELs/100 EC vs 2 IELs/100 EC, respectively). In 21% of CD cases, D2 were normal and the diagnosis could only be made on D1. Finally, 6% of CD cases showed isolated increase of IELs in D1 without architectural modification.

CONCLUSIONS

D1 allowed diagnosis of CD in 21% of cases and IEL >70 per 100 EC correlated strongly with CD. Between 40 and 70 IELs per 100 EC, CD is very likely but other DD must be considered. Finally, the preferential localisation of IELs above EC nuclei favours CD, and increased IEL in D1 may be the sole abnormality.

Coeliac disease and gluten-related disorders in childhood

Gluten-related disorders such as coeliac disease, wheat allergy and noncoeliac gluten sensitivity are increasingly being diagnosed in children. Coeliac disease occurs frequently, affecting 1-3% of the Western population. The condition manifests at a very young age, more so in girls, and is related to the HLA genotype. Coeliac disease might be considered a public health problem and, as primary prevention is not possible, the debate on mass screening should be reopened. Wheat proteins, including gluten, are responsible for one of the most common food allergies in children: wheat allergy. Unlike coeliac disease and wheat allergy, noncoeliac gluten sensitivity is an unclear and controversial entity. These three gluten-related disorders are treated with a gluten-free diet. In coeliac disease, the diet should be strictly followed, whereas wheat allergy only requires wheat elimination and in noncoeliac gluten sensitivity occasional trials of gluten reintroduction can be done. A good diagnostic work-up is important for gluten-related disorders in childhood to avoid unnecessary restrictive diets in children. In this Review, we provide an overview of the pathogenesis, diagnosis and management of the most common gluten-related disorders in children.

Adaptive diagnosis of coeliac disease

Coeliac disease has for a long time simply been regarded as a gluten-dependent enteropathy and a duodenal biopsy was required in all patients for the diagnosis. It is now accepted that autoimmunity against transglutaminase 2 is an earlier, more universal and more specific feature of coeliac disease than histologic lesions. Moreover, high serum levels of combined anti-transglutaminase 2 and anti-endomysium antibody positivity have excellent predictive value for the presence of enteropathy with villous atrophy. This makes the histology evaluation of the gut no longer necessary in well defined symptomatic paediatric patients with compatible HLA-DQ2 and/or DQ8 background. The biopsy-sparing diagnostic route is not yet recommended by gastroenterologists for adults, and certain clinical circumstances (immunodeficiency conditions, extraintestinal manifestations, type-1 diabetes mellitus, age less than 2 years) may require modified diagnostic approaches. Coeliac patients with preserved duodenal villous structure do exist and these need a more extended evaluation by immunologic and molecular biology tools.

Discriminant score for celiac disease based on immunohistochemical analysis of duodenal biopsies

OBJECTIVES

Celiac disease (CD) represents a spectrum, which includes cases with minor histological abnormalities (potential CD). The aim of this work is to evaluate the contribution of immunohistochemical analysis of duodenal biopsies to the diagnosis of gluten-related minor enteropathy.

METHODS

Duodenal biopsies from 56 patients with untreated CD and 56 controls were analyzed for CD3 and γδ intraepithelial lymphocyte number, γδ/CD3 ratio, and density of CD25+ lamina propria cells. A discriminant equation was obtained by which 61 more biopsies with normal villous architecture were blindly evaluated.

RESULTS

All of the immunohistochemical parameters were significantly different between patients with CD and controls. None of the single parameters showed sufficient specificity for CD. The combination of all of the 4 markers resulted in the following discriminant equation: discriminant score (Dscore) = (CD3 × 0.06) - (γδ × 0.119) + (CD25 × 0.012) + (γδ/CD3 × 0.131) - 4.709. Using this Dscore, patients were correctly classified as celiac or controls in 97.3% of the cases. When this equation was applied to a validation set of 61 patients with normal villous architecture and unknown diagnosis, 92.9% of those with a positive score turned out to be patients with potential CD. A normal score, however, did not exclude this condition.

CONCLUSIONS

Immunohistochemistry represents a specific tool for the diagnosis of CD, but does lack sensitivity in detecting all of the potential CD cases.

Duodenal lymphocytosis with no or minimal enteropathy: much ado about nothing?

Duodenal lymphocytosis is a nonspecific finding that is being detected with heightened frequency. Although increased intraepithelial lymphocytosis with normal villous architecture classically corresponds to grade 1 of the Marsh classification, many other conditions have been reported to be associated with this histologic pattern. In this article, we offer a broad review of the associations of isolated increased intraepithelial lymphocytosis with celiac and nonceliac gluten sensitivity, as well as of the broadening nonceliac etiologies.

Interleukin-18 gene promoter polymorphisms and celiac disease in Italian patients

Celiac disease (CD) is the most common food-sensitive enteropathy in genetically susceptible individuals. The major genetic risk factors known are specific human leukocyte antigen (HLA)-DQ haplotypes, but other genetic factors are supposed to be involved. Interleukin-18 (IL-18) is a pro-inflammatory cytokine that has an important role in the immune defense and it has the potential to influence inflammatory disorders. IL-18 is able to promote Th1 cell development and it is expressed in the mucosa of the small intestine in celiac patients. Given the IL-18 biological role, and since a few studies have previously suggested its involvement in CD, in order to investigate the role of IL18 gene in the susceptibility to CD we have performed a case-control study, analyzing two IL18 gene promoter polymorphisms, previously reported to impair the transcriptional activity of the gene, (-137G > C and -607C > A, rs187238 and rs1946518 respectively). A total of 556 CD Italian patients and 582 controls, further stratified for HLA class II (DQ) CD risk haplotypes were enrolled. The -607A > C A allele and A/A genotype, as well as the combination of this allele with the -137G allele in the AG haplotype, were associated with an increased risk towards CD development, in particular in HLA-DQ2.2 patients. Although the association was very moderate, our results indicate the possible involvement of IL18 gene in the susceptibility to CD, and for this reason we do think it should deserve further investigation.

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.

Potential celiac children: 9-year follow-up on a gluten-containing diet

OBJECTIVES

Potential celiac disease (CD) is defined by the presence of serum anti-tissue-transglutaminase (anti-TG2) antibodies and normal duodenal mucosa. The major clinical problem is the management of asymptomatic patients and how to predict the development of villous atrophy. This prospective longitudinal cohort study describes the natural history of potential CD up to 9 years and explores risk factors associated with the development of mucosal damage.

METHODS

Two hundred and ten potential CD children were eligible for the study; 175/210 asymptomatic children were left on a gluten-containing diet. Antibodies and clinical symptoms were checked every 6 months, and a small bowel biopsy was taken every 2 years to evaluate histological, immunohistochemical, and anti-TG2 deposits. Patients were genotyped for HLA and a set of non-HLA CD-associated genes.

RESULTS

Forty-three percent of patients showed persistently elevated anti-TG2 level, 20% became negative during follow-up, and 37% showed a fluctuant anti-TG2 course with transiently negative values. At 3 years of follow-up, 86% of cases remained potential; 73 and 67% still had normal duodenal architecture at 6 and 9 years, respectively. Male sex, slight mucosal inflammation at time 0, and a peculiar genetic profile delineate a cohort of individuals who were prone to develop mucosal damage during time.

CONCLUSIONS

A sizeable proportion of asymptomatic potential celiac patients showed fluctuation or negativization of antibody production, and many of these, with persistently positive anti-TG2, did not develop mucosal damage after 9 years of follow-up. Celiac population is a multivariate aggregate of individuals with different genetic and phenotypic profiles. Caution is required before prescribing a gluten-free diet for life to asymptomatic individuals with potential CD.

A practical approach to small bowel biopsy interpretation: celiac disease and its mimics

While celiac disease is the most common cause of villous remodeling and intraepithelial lymphocytosis in the proximal small bowel, there are many entities that can mimic its histologic appearance. The purpose of this review is to discuss normal small bowel histology and the differential diagnosis of celiac disease. Approaches to evaluate increased intraepithelial lymphocytes are presented, followed by a detailed discussion of the pathology of celiac disease. Particular emphasis is given to those conditions that cause intraepithelial lymphocytosis in the setting of preserved villous architecture, although other important entities, such as peptic injury, idiopathic inflammatory bowel disease, medication injury, eosinophilic (allergic) gastroenteritis, autoimmune enteropathy, common variable immunodeficiency, and infections are also reviewed.

The clinical significance of duodenal lymphocytosis with normal villus architecture

CONTEXT

The finding of increased intraepithelial lymphocytes with normal villous architecture (Marsh I lesion) is seen in up to 3% of duodenal biopsies. The differential diagnosis includes a wide range of possibilities, including celiac disease, bacterial overgrowth, nonsteroidal antiinflammatory drug damage, reaction to Helicobacter pylori infection, tropical sprue, and chronic inflammatory bowel disease.

OBJECTIVES

To highlight the histologic features of the Marsh I lesion, review the diseases and conditions associated with that finding, and to provide pathologists with a rationale and a template for how to identify and report such cases.

DATA SOURCES

A review of the literature regarding the histologic features and clinical associations of Marsh I lesions.

CONCLUSIONS

Marsh I lesions are a nonspecific finding associated with a number of disease conditions. Historically, between 9% and 40% of cases have been shown to represent celiac disease. Current data do not suggest histologic features to differentiate between diseases associated with this histologic change.

Decreased Expression of Protease Inhibitor 9, a Granzyme B Inhibitor, in Celiac Disease: A Potential Mechanism in Enterocyte Destruction and Villous Atrophy

The objective of this study was to assess the expression of protease inhibitor 9, a granzyme B inhibitor, in human small intestine, and to evaluate its cytoprotective role in the celiac disease of children. Twelve subjects with untreated celiac disease and thirteen healthy controls were examined by endoscopy. The expression of protease inhibitor 9 was analyzed immunohistochemically from duodenal biopsies and compared to granzyme B expression, apoptosis rate, number of intraepithelial lymphocytes and villus and crypt height data from the biopsies. We discovered that protease inhibitor 9 is expressed in the cytoplasm of the duodenal epithelial cells in the majority of cases. The enterocyte expression of protease inhibitor 9 was lower in celiac disease patients than in controls. Protease inhibitor 9 expression also showed a negative correlation with the number of apoptotic cells, overall density of granzyme B expressing intraepithelial lymphocytes, the height of the crypts and the severity of villous atrophy in duodenum. Therefore, we conclude that the protease inhibitor 9 is constantly expressed in the enterocytes of normal duodenum and the expression is decreased in celiac disease. These findings suggest that protease inhibitor 9 has a role in duodenal homeostasis and in the protection of enterocytes from misdirected granzyme B. Indeed, observed associations of lowered protease inhibitor 9 expression together with increased granzyme B expression, apoptosis rate and severity of villous atrophy suggest that impaired balance between granzyme B mediated cytotoxicity and its inhibition by protease inhibitor 9 forms an important factor in the pathogenesis of villous atrophy in celiac disease.

Immunohistochemical stains for CD3 and CD8 do not improve detection of gluten-sensitive enteropathy in duodenal biopsies

Patients with gluten-sensitive enteropathy usually have increased numbers of duodenal intraepithelial lymphocytes even if the villous architecture is normal. Some authors advocate the use of CD8 and CD3 immunohistochemical stains to improve detection of intraepithelial lymphocytosis, yet the added value of immunohistochemistry when biopsies appear normal remains unproven. The purpose of this study was to evaluate the utility of CD3 and CD8 immunostains in detecting intraepithelial lymphocytosis among duodenal biopsies originally interpreted to be normal based on routine evaluation. We identified 200 duodenal biopsies from 172 patients, all of which were accompanied by a clinical question of gluten-sensitive enteropathy. Five well-oriented villi from each biopsy were assessed. Intraepithelial lymphocytes present in hematoxylin and eosin (H&E)-stained slides were counted and compared with the number of CD3 and CD8 immunopositive cells present in the villous epithelium. Results were expressed as the mean number of intraepithelial lymphocytes or immunopositive cells present per 20 villous tip enterocytes. Review of H&E-stained slides revealed a mean of 2.1 ± 0.1 intraepithelial lymphocytes, compared with 3.2 ± 0.1 CD3-positive and 2.1 ± 0.1 CD8-positive intraepithelial cells (P=<0.001 and 1, respectively), although none of the cases displayed sufficient numbers of intraepithelial lymphocytes to be considered abnormal (ie, ≥ 12/20 enterocytes) by any method. The number of intraepithelial lymphocytes detected by H&E evaluation or immunohistochemistry did not correlate with results of serologic studies for markers of gluten sensitivity. We conclude that immunostains for T cell markers do not improve detection of gluten-sensitive enteropathy when H&E-stained sections are normal.

Neutrophilic infiltration in gluten-sensitive enteropathy is neither uncommon nor insignificant: assessment of duodenal biopsies from 267 pediatric and adult patients

The histologic findings of celiac disease, that is, gluten-sensitive enteropathy (GSE), are dominated by increased intraepithelial lymphocytes, villous blunting, lymphoplasmacytic infiltration of lamina propria, and crypt hyperplasia. To date, neutrophils have not been thought to constitute a significant cell type in GSE, and their presence often invokes consideration of alternative diagnoses. Thus, we sought to determine the prevalence and severity of neutrophilic infiltration in duodenal biopsies from patients with GSE. The degree of neutrophilic infiltration and features characteristic of GSE were assessed in duodenal biopsies from 267 clinically confirmed GSE patients (116 adults and 151 children). These specimens were graded by the disease activity score (DAS) and the neutrophilic activity score (NAS). Gastric antral biopsies obtained from 195 patients were also evaluated for lymphocytic gastritis. NAS was correlated with DAS and other clinicopathologic features. We found that 56% of pediatric and 28% of adult GSE patients had significant duodenal neutrophilia. NAS was higher in children than in adults (2.3 vs. 1.2, P<0.001). Multivariate regression showed that DAS, eosinophilic infiltration, and foveolar metaplasia correlated positively, and age correlated negatively with NAS. Lymphocytic gastritis was seen in 21.5% of the gastric biopsies. The presence of lymphocytic gastritis correlated positively with NAS and DAS, and in the pediatric population it correlated negatively with age. Significant duodenal neutrophilia is often found in patients with celiac disease, especially in the pediatric population, and is associated with more active disease. Thus, the findings of duodenal neutrophilia in biopsies, otherwise consistent with GSE, should not preclude the diagnosis of GSE.

Histopathology of celiac disease

Small bowel biopsy remains the gold standard for diagnosing celiac disease (CD). Intraepithelial lymphocytosis in the context of villous atrophy is considered a characteristic histologic finding of CD. However, studies have also indicated that the detection of intraepithelial lymphocytosis in the absence of villous atrophy is not specific for CD, having been documented in other small intestinal disorders. This review summarizes key aspects regarding the histopathologic assessment, impact of the site and number of small bowel biopsy samples on diagnosis, old and emerging classifications, and benefit of standardized pathology report in the diagnostic workup of CD.

An update on celiac disease histopathology and the road ahead

CONTEXT

Celiac disease (CD) is a common immune-mediated disorder that occurs in genetically predisposed individuals (carriers of HLA-DQ2 and DQ8 haplotypes) on consumption of wheat (gluten). It is characterized by inflammation of the small-intestinal mucosa and myriad gastrointestinal and systemic manifestations. Celiac disease is common in the general population (prevalence, 0.5%-1%). Currently, small-bowel biopsy is considered the gold standard for diagnosing CD. However, the role of serologic testing in the diagnosis of CD has evolved, from being a supportive test to supplanting intestinal biopsies in certain patient populations.

OBJECTIVE

To summarize key aspects of histopathologic assessment, discuss the benefit of standardized pathology reports, impact of the site and number of small-bowel biopsy samples on diagnosis, and recommendations regarding serologic testing.

DATA SOURCES

Literature review of publications on CD and experience with histopathologic review of biopsies at the Department of Pathology and Cell Biology, Columbia University Medical Center, New York-Presbyterian Hospital, New York.

CONCLUSIONS

Intraepithelial lymphocytosis in the context of villous atrophy is considered a characteristic histologic finding of CD; however, it is a rather nonspecific finding. A growing list of publications has also indicated that the detection of intraepithelial lymphocytosis in the absence of villous atrophy has rather low specificity for CD. Therefore, communication between pathologists and gastroenterologists is paramount, as is knowledge regarding the pertinent clinical and laboratory data, in distinguishing between CD and other disorders with similar histopathologic and clinical manifestations.

European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for the diagnosis of coeliac disease

OBJECTIVE

Diagnostic criteria for coeliac disease (CD) from the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) were published in 1990. Since then, the autoantigen in CD, tissue transglutaminase, has been identified; the perception of CD has changed from that of a rather uncommon enteropathy to a common multiorgan disease strongly dependent on the haplotypes human leukocyte antigen (HLA)-DQ2 and HLA-DQ8; and CD-specific antibody tests have improved.

METHODS

A panel of 17 experts defined CD and developed new diagnostic criteria based on the Delphi process. Two groups of patients were defined with different diagnostic approaches to diagnose CD: children with symptoms suggestive of CD (group 1) and asymptomatic children at increased risk for CD (group 2). The 2004 National Institutes of Health/Agency for Healthcare Research and Quality report and a systematic literature search on antibody tests for CD in paediatric patients covering the years 2004 to 2009 was the basis for the evidence-based recommendations on CD-specific antibody testing.

RESULTS

In group 1, the diagnosis of CD is based on symptoms, positive serology, and histology that is consistent with CD. If immunoglobulin A anti-tissue transglutaminase type 2 antibody titers are high (>10 times the upper limit of normal), then the option is to diagnose CD without duodenal biopsies by applying a strict protocol with further laboratory tests. In group 2, the diagnosis of CD is based on positive serology and histology. HLA-DQ2 and HLA-DQ8 testing is valuable because CD is unlikely if both haplotypes are negative.

CONCLUSIONS

The aim of the new guidelines was to achieve a high diagnostic accuracy and to reduce the burden for patients and their families. The performance of these guidelines in clinical practice should be evaluated prospectively.

Selected disorders of malabsorption

Malabsorption syndrome encompasses numerous clinical entities that result in chronic diarrhea, abdominal distention, and failure to thrive. These disorders may be congenital or acquired and include cystic fibrosis and Shwachman-Diamond syndrome; the rare congenital lactase deficiency; glucose-galactose malabsorption; sucrase-isomaltase deficiency; adult-type hypolactasia leading to acquired lactose intolerance. The pathology may be due to impairment in absorption or digestion of nutrients resulting in Nutritional deficiency, gastrointestinal symptoms, and extra gastrointestinal symptoms. Treatment is aimed at correcting the deficiencies and symptoms to improve quality of life. Common disorders of malabsorption celiac disease, pernicious anemia, and lactase deficiency are discussed in this article.

Coeliac Disease in the 21st Century: No Longer "Kids' Stuff"

Background

We aimed to determine if Coeliac disease (CD) can be still be considered a predominantly paediatric disorder, in spite of the increased incidence of adult-onset CD reported in recent years.

Methods

An observational, descriptive, and retrospective study was developed at two Spanish hospitals. Data was collected and analyzed from all paediatric and adult patients newly diagnosed with CD throughout the year 2010. CD diagnoses were based on a concordant clinical history, serology, HLA-DQ compatibility, the presence of mucosal lesions in duodenal biopsies with gluten dependence of symptoms, and histological lesions.

Results

A total of 79 patients were diagnosed with CD throughout 2010, of which 68 (86.1%) were adults. Classic symptoms (diarrhoea and iron-deficiency anaemia) were more frequent in children (90.9%), being present in only 54.4% of adults (p = 0.02). Adult patients showed, mainly, abdominal pain, dyspepsia, and GERD-related symptoms. Villous atrophy (Marsh III) was present in 63.7% of children, but only in 19.1% of adults (p = 0.004). Positive tTGA was present in 81.8% of the children and only in 19.1% of the adults (p = 0.004). Haemoglobin levels were significantly lower in children (p = 0.025), but no differences were observed in iron and ferritin blood levels.

Conclusions

Our study shows that adult-onset CD was the predominant presentation in two hospitals in Spain in the year 2010. Therefore, CD can no longer be considered a predominantly paediatric disorder. Marsh I and negative tTGA titters are characteristic in most of adults. New diagnostic algorithms are needed to improve correct diagnosis of CD in adults.