Refractory sprue, coeliac disease, and enteropathy-associated T-cell lymphoma. French Coeliac Disease Study Group

[Celiac disease]

Celiac disease is an enteropathy due to gluten intake in genetically predisposed individuals (HLA DQ2/DQ8). Celiac disease occurs in adults and children at rates approaching 1% of population in Europe and USA. Clinical features observed in celiac disease are extremely various and anaemia, oral aphthous stomatis, amenorrhea or articular symptoms may be the only presenting manifestations. Diagnosis relies on the evidence of histological villous atrophy in proximal small bowel and the presence of specific serum antibodies. Treatment relies on eviction of gluten (wheat, barley, rye) from diet. Gluten free diet allows prevention of malignant complications such as small bowel adenocarcinoma and lymphoma, and osteopenia. The main cause of resistance to gluten free diet is its poor observance. If not the case, serious complications of celiac disease, such as clonal refractory celiac sprue and intestinal T-cell lymphoma should be suspected. Current therapeutic challenges concern alternative to gluten free diet and new efficient treatments of lymphomatous complications.

PPAR signaling pathway and cancer-related proteins are involved in celiac disease-associated tissue damage

Celiac disease (CD) is an immune-mediated disorder triggered by the ingestion of wheat gliadin and related proteins in genetically predisposed individuals. To find a proteomic CD diagnostic signature and to gain a better understanding of pathogenetic mechanisms associated with CD, we analyzed the intestinal mucosa proteome alterations using two dimensional difference gel electrophoresis (2D-DIGE) coupled with matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF ms) of CD patients with varying degrees of histological abnormalities defined by Marsh criteria and controls. Our results clearly evidenced the presence of two groups of patients: Group A, including controls and Marsh 0-I CD patients; and Group B, consisting of CD subjects with grade II-III Oberhuber-Marsh classification. Differentially expressed proteins were involved mainly in lipid, protein and sugar metabolism. Interestingly, in Group B, several downregulated proteins (FABP1, FABP2, APOC3, HMGCS2, ACADM and PEPCK) were implicated directly in the peroxisome proliferator-activated receptor (PPAR) signaling pathway. Moreover, Group B patients presented a deregulation of some proteins involved in apoptosis/survival pathways: phosphatidylethanolamine-binding protein 1 (PEBP1), Ras-related nuclear protein (Ran) and peroxiredoxin 4 (PRDX4). PEBP1 downregulation and RAN and PRDX4 upregulation were associated with more severe tissue damage. Likewise, IgMs were found strongly upregulated in Group B. In conclusion, our results indicate that a downregulation of proteins involved in PPAR signaling and the modulation of several cancer-related proteins are associated with the highest CD histological score according to Oberhuber-Marsh classification.

Autoimmunity, autoinflammation and lymphoma in combined immunodeficiency (CID)

A number of primary immunodeficiencies are associated with autoimmune phenomena, e.g. Wiskott-Aldrich Syndrome, Common Variable Immunodeficiency and Hyper-IgM Syndrome. The common denominator is a dysregulation of immune responses affecting T and B cells with central and/or peripheral tolerance mechanisms being disturbed. Autoimmunity and autoinflammation may also occur in atypical phenotypes of combined immunodeficiencies (CID) usually associated with severe infectious complications. These unexpected presentations of classical CID are very instructive in how low numbers of T and B cells go hand in hand with skewing of lymphoid repertoires and function. The resulting immune dysregulation may lead to self-reactivity with organ damage and malignancy.

Enteropathy associated T-cell lymphoma and its precursor lesions

Enteropathy Associated T-cell Lymphoma (EATL) is an intestinal tumour of intra-epithelial lymphocytes. Based on morphology, immunohistochemistry and genetic profile EATL can be divided into two groups. EATL type I is a large cell lymphoma which is highly associated with Coeliac Disease (CD) and mostly presents with malabsorption, weight loss and CD-related symptoms. EATL type II consists of small to medium-sized cells and presents often with obstruction or perforation of the small bowel. This type of EATL has no known association with CD. When EATL has been diagnosed a thorough diagnostic work-up is needed. This work-up preferably includes video capsule enteroscopy (VCE), double-balloon enteroscopy (DBE), computed tomography (CT) combined with 18F-fluorodeoxyglucose positron emission tomography scan (18F-FDG-PET scan) if possible and magnetic resonance enteroclysis (MRE). Nowadays, most EATL patients are treated with chemotherapy mostly preceded by resection of the tumour and followed by stem cell transplantation. Despite these therapies outcome of EATL remains very poor with a 5-year survival of 8-20%. In order to improve survival prospective multicentre trials, studying new therapies are needed. The combination of chemotherapy, monoclonal antibodies and/or apoptosis inducing small molecules might be a potential treatment for EATL in the (nearby) future.

Diagnosis and staging in gastrointestinal lymphoma

The diagnosis gastrointestinal lymphoma can be made on endoscopic biopsies in the vast majority of cases. Definitive subtyping of the lymphoma according to the WHO classification with the use of additional immunological and molecular markers is the cornerstone for further decision making. Several lymphomas may occur multifocally or show both small cell and large cell components. Therefore, a second endoscopy with an extensive biopsy protocol (mapping) may be mandatory. Staging procedures are required for therapeutic decision making and should include CT-scan, laboratory studies and bone marrow examination as required in other lymphomas. Additional studies must be performed depending subtype and localisation of the lymphoma. In gastric lymphoma endosonography reveals prognostic information. In marginal zone lymphoma of MALT-type attention to other MALT-sites and autoimmune diseases is necessary. In enteropathy-associated T-cell lymphoma screening for coeliac disease and enteroscopy are required. In several lymphomas (diffuse large B-cell lymphoma and mantle cell lymphoma) a PET-scan is considered as standard of care. The value of staging procedures after treatment is less well defined. At least in gastric lymphomas, histology is the gold standard after treatment and during follow-up.

Collagenous sprue is not always associated with dismal outcomes: a clinicopathological study of 19 patients

Collagenous sprue is associated with high morbidity; however, the etiology of this disorder is unclear. Data regarding the pathological and clinical manifestations of patients with collagenous sprue are also limited. We, thus, undertook this study to gain insight into the etiology, disease manifestations and outcomes of collagenous sprue. We searched our departmental database (1999-2008) to identify cases of collagenous sprue and to obtain clinical and laboratory data. Small bowel histology, including thickness of subepithelial collagen, intra-epithelial lymphocyte phenotype and results of T-cell clonality assays were evaluated. Nineteen patients (15 women, 4 men, age 22-80 years, mean 57 years) were identified. Seventeen (89%) had celiac disease and two had unclassified sprue; 9 of 17 (53%) celiac disease patients had refractory disease; 5 of 15 (33%) lacked diarrhea (atypical presentation), including 2 of 6 (33%) with active (untreated) celiac disease and 3 of 9 (33%) with refractory celiac disease. Autoimmune disorders were seen in 12 of 19 (63%) patients and microscopic colitis (n=7), lymphocytic gastritis (n=2) or collagenous gastritis (n=2) were seen in nine patients. Subepithelial collagen thickness was mildly (n=6), moderately (n=10), or markedly (n=3) increased and villous atrophy was total (n=13) or subtotal (n=6). Phenotypically aberrant intraepithelial lymphocytes were not detected in any case. Polymerase chain reaction analysis showed a dominant T-cell clone in the only patient with refractory celiac disease type II. Histological improvement occurred in 7 of 11 (64%) patients. Overall, 8 of 19 (42%) responded to gluten-free diet, including 2 of 9 (22%) with refractory celiac disease and 10 responded to immunomodulatory therapy, including 6 of 9 (67%) with refractory celiac disease. Only one patient died from complications of refractory celiac disease. No patient developed lymphoma. The vast majority of our patients with collagenous sprue had celiac disease. Although, many patients required immunomodulatory therapy for symptom control, a subset responded to gluten-free diet alone. In our experience, collagenous sprue patients had relatively good clinical outcomes.

Celiac disease: from pathogenesis to novel therapies

Celiac disease has become one of the best-understood HLA-linked disorders. Although it shares many immunologic features with inflammatory bowel disease, celiac disease is uniquely characterized by (1) a defined trigger (gluten proteins from wheat and related cereals), (2) the necessary presence of HLA-DQ2 or HLA-DQ8, and (3) the generation of circulating autoantibodies to the enzyme tissue transglutaminase (TG2). TG2 deamidates certain gluten peptides, increasing their affinity to HLA-DQ2 or HLA-DQ8. This generates a more vigorous CD4(+) T-helper 1 T-cell activation, which can result in intestinal mucosal inflammation, malabsorption, and numerous secondary symptoms and autoimmune diseases. Moreover, gluten elicits innate immune responses that act in concert with the adaptive immunity. Exclusion of gluten from the diet reverses many disease manifestations but is usually not or less efficient in patients with refractory celiac disease or associated autoimmune diseases. Based on the advanced understanding of the pathogenesis of celiac disease, targeted nondietary therapies have been devised, and some of these are already in phase 1 or 2 clinical trials. Examples are modified flours that have been depleted of immunogenic gluten epitopes, degradation of immunodominant gliadin peptides that resist intestinal proteases by exogenous endopeptidases, decrease of intestinal permeability by blockage of the epithelial ZOT receptor, inhibition of intestinal TG2 activity by transglutaminase inhibitors, inhibition of gluten peptide presentation by HLA-DQ2 antagonists, modulation or inhibition of proinflammatory cytokines, and induction of oral tolerance to gluten. These and other experimental therapies will be discussed critically.

Aberrant T-lymphocytes in refractory coeliac disease are not strictly confined to a small intestinal intraepithelial localization

BACKGROUND

Refractory coeliac disease (RCD) is characterized by persisting mucosal pathology in spite of a strict gluten free diet (GFD). In RCD type II, phenotypically aberrant (CD7+CD3-CD4/8-cytoplasmicCD3+) T-lymphocytes are present within the intraepitelial lymphocyte (IEL) population in the small intestine, and 50-60% of these patients develops an enteropathy associated T-cell lymphoma (EATL).

AIM

To investigate whether aberrant T-lymphocytes in RCD II can be detected in other parts of the small intestinal mucosa besides the intraepithelial compartment. Additionally, the presence of aberrant T-lymphocytes was analyzed in two RCD II patients that developed atypical skin lesions.

METHODS

Multiparameter flow cytometric immunophenotyping was performed on both IEL and lamina propria lymphocyte (LPL) cell suspensions, isolated from small bowel biopsy specimens of RCD II patients (n = 14), and on cutaneous lymphocytes isolated from skin-lesion biopsy specimens of RCD II patients (n = 2). In addition, immunofluorescence analysis of frozen RCD II derived small intestinal biopsies was performed.

RESULTS

Our results clearly show that aberrant T-lymphocytes may be present in both the IEL and the LPL compartments of RCD II derived small intestinal biopsies. Although the highest percentages are always present in the IEL compartment, aberrant LPL can exceed 20% of total LPL in half the RCD II patients. Interestingly, cutaneous lymphocytes isolated from atypical skin lesions that developed in some RCD II patients showed a similar aberrant immunophenotype as found in the intestinal mucosa.

CONCLUSIONS

In RCD II, the aberrant T-lymphocytes may also reside in the subepithelial layer of the small intestinal mucosa, in the lamina propria, and even in extraintestinal localizations including the skin. Whether this phenomenon represents a passive overflow from the intestinal epithelium or active trafficking towards other anatomical localizations remains to be elucidated. RCD II appears to be a disseminated disease, which may impose the risk of EATL development outside the intestine.

Endocytoscopy for the detection of microstructural features in adult patients with celiac sprue: a prospective, blinded endocytoscopy-conventional histology correlation study

BACKGROUND

Endocytoscopy (EC) is a novel technique that allows magnified live inspection of the intestinal mucosa.

OBJECTIVE

To evaluate EC for the detection of key pathological findings in patients with celiac sprue.

DESIGN

A total of 166 EC recordings were prospectively acquired. Matched videos, images, and biopsy specimens were obtained by duodenal argon beamer labeling of the respective sites.

SETTING

Academic tertiary referral center.

PATIENTS

Forty patients (mean age 51.5 years, 70% women) with established (n = 32) or suspected (n = 8) celiac disease (CD).

INTERVENTIONS

A validated scoring system (Marsh classification) was used to assess disease activity. EC criteria were independently evaluated by 2 gastroenterologists and 1 pathologist.

MAIN OUTCOME MEASUREMENTS

The primary endpoint was to examine EC correlation with conventional CD histology.

RESULTS

Of 166 duodenal biopsy sites, 23% were classified as Marsh III (moderate to severe), 10% as Marsh I (mild), and 67% as Marsh 0 (normal). Using the 450x magnification, we found that identification of crypts was diagnostic for celiac pathology. Four criteria were significant predictors of Marsh III pathology when adjusted by multivariate analysis: low number of villi per visual field (<3; odds ratio [OR] 9.1; 95% CI, 1.3-62.0), confluence of villi (OR 37.1; 95% CI, 1.3-1021.2), irregular epithelial lining (OR 10.9; 95% CI, 2.5-46.7), and inability to delineate loop capillaries (OR 14.9; 95% CI, 3.3-67.0). None was a good predictor of Marsh I pathology.

LIMITATIONS

Single-center experience. No prospective validation of the criteria in an independent patient population.

CONCLUSIONS

EC at 450x magnification accurately identifies mucosal histopathology of advanced CD, but not early morphological changes.

Free perforation of the small intestine in collagenous sprue

A 67-year-old man with celiac disease developed recurrent diarrhea, profound weakness and weight loss, with evidence of marked protein depletion. His clinical course was refractory to a strict gluten-free diet and steroid therapy. Postmortem studies led to definition of unrecognized collagenous sprue that caused ulceration and small intestinal perforation. Although PCR showed identical monoclonal T-cell populations in antemortem duodenal biopsies and postmortem jejunum, careful pathological evaluation demonstrated no frank lymphoma. Rarely, overt or even cryptic T-cell lymphoma may complicate collagenous sprue, however, small intestinal ulcers and perforation may also develop independently. The dramatic findings here may reflect an underlying or early molecular event in the eventual clinical appearance of overt T-cell lymphoma.

Celiac disease in the elderly

It has become apparent recently that celiac disease, once believed to be primarily a childhood disease, can affect people of any age. Epidemiologic studies have suggested that a substantial portion of patients are diagnosed after the age of 50. Indeed, in one study, the median age at the diagnosis was just under the age of 50 with one-third of new patients diagnosed being older than 65 years. The purpose of this review is to address the prevalence, clinical features, diagnosis, and consequences of celiac disease in the elderly. The authors also review management strategies for celiac disease and adjust these with emphasis on the particular nutritional and nonnutritional consequences or associations of celiac disease as they pertain to the elderly.

Recent advances in refractory coeliac disease: a review

Coeliac disease (CD) is an immune-mediated disease of the small intestine caused by intolerance to gluten. Removal of gluten from the diet results in a return to normal health for the majority of patients. A significant proportion of patients do not respond to a gluten-free diet and are considered to be suffering from refractory coeliac disease (RCD). Two types of RCD are now recognized: type 1 RCD is characterized by a polyclonal population of intraepithelial lymphocytes (IELs) with a normal immunophenotype, and type 2 RCD shows monoclonal IELs with an aberrant immunoprofile. Patients with RCD have a high risk of complications such as ulcerative jejunitis (UJ) and enteropathy-type T-cell lymphoma (ETTL). RCD2 may represent an early stage in the development of overt lymphoma. The diagnosis of RCD, therefore, has important implications, but remains a challenging area. In this paper we review the latest developments in RCD, including the diagnostic approach and a discussion of the key clinical, histological, immunohistochemical and molecular features of RCD and its complications.

Symposium 1: Joint BAPEN and British Society of Gastroenterology Symposium on ‘Coeliac disease: basics and controversies’ Coeliac disease: optimising the management of patients with persisting symptoms?

The vast majority of patients with coeliac disease will derive benefit from a gluten-free diet. However, some patients will not improve on the gluten-free diet or they will have a relapse of their symptoms. The present review will focus on this group of patients. Definitions for non-responsive coeliac disease and refractory coeliac disease will be provided. The most common reason for recurrent symptoms is continued gluten exposure. Other causes of persisting symptoms are discussed, including alternative causes of villous atrophy or co-existent pathology. Current literature is reviewed, including an initial investigation strategy for patients with persisting symptoms. A pragmatic management plan is described that can be initiated by any clinician. Finally, the current optimal investigational pathway for patients with refractory (or suspected refractory) coeliac disease is discussed and the reported effects of a number of therapeutic options are summarised. The aim of the present article is to provide clinicians with an up-to-date review of the literature in this clinical field and allow them to determine the most appropriate management strategy.

A blinded pilot comparison of capsule endoscopy and small bowel histology in unresponsive celiac disease

This study compares video capsule endoscopy (VCE) with histological specimens of proximal small bowel in patients with celiac disease who have failed to respond to a gluten-free diet. Patients with nonresponsive celiac disease underwent capsule endoscopy, and concordance between endoscopy and histology was then calculated using the kappa statistic. In 19 patients, endoscopy videos were reported as normal in ten (53%) case, as having mild changes in three (16%) cases, and as having moderate-severe changes in six (31%) cases. Two (11%) had acute ulcers. No small bowel tumors were seen. Endoscopy demonstrated concordance with histological changes in 14 of the 18 patients with histology available (78% concordance). The kappa statistic suggested a substantial degree of concordance between histology and endoscopic findings. Endoscopy with distal duodenal biopsies is superior to VCE in detecting proximal, nonresponsive celiac disease, but more distal lesions may be missed such that the strength of VCE lies in its ability to visualize the entire small bowel.

Coeliac disease

Coeliac disease is a chronic inflammatory disorder of the small bowel induced in genetically susceptible people by the irritant gluten and possibly other environmental cofactors. The disorder is characterised by a diverse clinical heterogeneity that ranges from asymptomatic to severely symptomatic, and it manifests with frank malabsorption, an increased morbidity attributable to the frequent association with autoimmune disorders and increased mortality resulting from the emergence of T-cell clonal proliferations that predispose the patient to enteropathy-type T-cell lymphoma. Our understanding of the molecular basis for this disorder has improved and enabled the identification of targets for new therapies, although a strict gluten-free diet remains the mainstay of safe and effective treatment. In this Seminar we critically reassess the clinical and diagnostic aspects of this disease and new perspectives in its pathogenesis and treatment.

Malignancy in adult celiac disease

Prior studies have suggested that the incidence of some neoplastic disorders, particularly malignant lymphoma and small intestinal adenocarcinoma, are increased in celiac disease. Earlier studies from the United Kingdom have also suggested a link between celiac disease and esophageal carcinoma, although this has not been confirmed in North America. The risk of other gastrointestinal cancers seems to be limited. Gastric cancer does not appear to be detected more frequently, although direct endoscopic visualization of the upper gastrointestinal tract is now very common in patients with celiac disease. Colon cancer also appears to be limited in celiac disease, even in patients first diagnosed with celiac disease late in life. This has led to the hypothesis that untreated celiac disease may be protective, possibly owing to impaired absorption of fat or fat-soluble agents, including hydrocarbons and putative co-carcinogens implicated in the pathogenesis of colon cancer, which may be poorly absorbed and rapidly excreted.

Aspects of B-cell non-Hodgkin's lymphoma development: a transition from immune-reactivity to malignancy

The development of B-cell lymphomas is an intricate interplay among various pathogenic factors, leading to a multi-step process, encompassing various stages of B-cell maturation. Besides genetic abnormalities, a variety of environmental and microbial factors, as well as disproportional immune-regulatory processes lead to the malignant transformation. Yet, little is known about the exact chain of events, which lead from the physiological polyclonal B-cell activation as a response to exogenous antigens through oligoclonality to a monoclonal, uncontrolled, malignant B-cell proliferation. The aim of the present review was to summarize the potential harmful steps in the development of B-cell lymphomas, according to conventional and novel theories, and to depict therapeutic regimens presently in use as well as to envision future drug developments, beneficial in the battle against this lymphoid malignancy.

Selected luminal mucosal complications of adult celiac disease

Celiac disease is a gluten-dependent intestinal disorder that appears to be associated with several clinical conditions. Some involve the luminal mucosa of the stomach and intestinal tract and may, occasionally, complicate the course of celiac disease. Collagenous colitis has been associated with celiac disease and may lead to chronic diarrhea. Conversely, some of these clinical disorders that involve the luminal mucosa of the stomach and intestine may represent the initial clinical presentation of celiac disease. These disorders should be considered in patients with celiac disease who develop recurrent or refractory symptoms despite adherence to a strict gluten-free diet. Detection of collagenous disorders that affect the luminal mucosa of the stomach or intestinal tract may result in recognition of underlying celiac disease.

Incidence and outcomes of the peripheral T-cell lymphoma subtypes in the United States

Peripheral T-cell lymphomas (PTCL) represent a small subgroup of non-Hodgkin lymphomas historically difficult to diagnose. We conducted a comprehensive assessment of 3287 PTCL cases diagnosed from 1992 to 2005 in 13 Surveillance, Epidemiology and End Results registries. Incidence trends, age-adjusted incidence rates and relative survival rates were compared across the study period, and by sex, race and age groups. From 1992 to 2005, PTCL incidence increased by 280%. Age-adjusted incidence rates were higher in males (Male/Female incidence rate ratio (IRR) 1.8) and in Blacks (Black/White IRR 1.2). Asian predominance was pronounced for extranodal NK/T-cell lymphoma, nasal type. Whites had higher 5-year survival than other racial groups for most histologic subtypes; however, the differences were not statistically significant. The variance in incidence rates and outcomes across PTCL subtypes support the pursuit of ongoing research to identify the etiology, pathophysiology, treatment patterns and differences in treatment response for PTCL subsets.

Clinical staging and survival in refractory celiac disease: a single center experience

BACKGROUND & AIMS

Refractory celiac disease (RCD) occurs when both symptoms and intestinal damage persist or recur despite strict adherence to a gluten-free diet. In RCD, the immunophenotype of intraepithelial lymphocytes may be normal and polyclonal (RCD I) or abnormal and monoclonal (RCD II). The aim is to describe the clinical characteristics, treatment, and long-term outcome in a large single-center cohort of patients with RCD.

METHODS

We compared the clinical characteristics and outcome in 57 patients with RCD: 42 with RCD I and 15 with RCD II.

RESULTS

Fifteen of 57 patients died during follow-up (n=8 with RCD I and n=7 with RCD II), each within the first 2 years after RCD diagnosis. The overall 5-year cumulative survival is 70%, 80%, and 45% for the entire cohort, RCD I, and RCD II, respectively. The refractory state itself and enteropathy-associated T-cell lymphoma (EATL) were the most common causes of death, respectively. A new staging system is proposed based on the cumulative effect of 5 prognostic factors investigated at the time of the refractory state diagnosis: for patients in stages I, II, and III, the 5-year cumulative survival rate was 96%, 71%, and 19%, respectively (P< .0001).

CONCLUSIONS

RCD is associated with high mortality with RCD II having an especially poor prognosis because of the development of EATL. A new staging model is proposed that may improve the precision of prognosis in patients with RCD.

Presentation and long-term follow-up of refractory celiac disease: comparison of type I with type II

BACKGROUND & AIMS

Refractory celiac disease (RCD) was recently subdivided into 2 subtypes (RCD I and II) based on a normal or abnormal phenotype of intraepithelial lymphocytes (IELs), respectively. It is not clear, however, if these 2 entities differ in their presentation at diagnosis or long-term outcome. We compared the clinical and biological characteristics of RCD I and RCD II at diagnosis, the risk of developing an overt lymphoma, and the predictive factors of survival.

METHODS

Medical files of 14 patients with RCD I and 43 with RCD II were analyzed retrospectively. Predictive factors of overt lymphoma and survival were studied in univariate and multivariate analyses.

RESULTS

At diagnosis, malnutrition, ulcerative jejunitis, and lymphocytic gastritis were more common in patients with RCD II than RCD I (P< .05). Overt lymphomas occurred in 2 patients with RCD I and 16 with RCD II. In the univariate analysis, abnormal IEL phenotype and increased age at diagnosis of RCD were predictive factors for overt lymphoma. Abnormal IEL phenotype (P< .01), clonality (P= .01), and overt lymphoma (P= .001) predicted short survival time. Only abnormal IEL phenotype (P= .03) and overt lymphoma (P= .04) were predictive in the multivariate analysis. The 5-year survival rate was 93% in patients with RCD I and 44% with RCD II.

CONCLUSIONS

RCD II has a much more severe presentation and prognosis than patients with RCD I; <44% of patients with RCD II survive 5 years after diagnosis. Abnormal IEL phenotype is a predictive factor but not a necessary condition for the development of overt lymphoma.

Celiac Disease in the 21st Century: Issues of Under-and Over-Diagnosis

Until the 1960s celiac disease (CD) or sprue was considered a pediatric disease that was rarely diagnosed in adulthood. Thanks to greater awareness of the disease and the availability of improved diagnostic tools (above all, sophisticated endoscopic techniques and the development of reliable serological markers), the prevalence of CD in Western countries has been increasing steadily, and it is now recognized as a common disorder, even in adults. However, many cases of this disease still go undiagnosed, especially among the elderly and in patients with atypical clinical presentations (which are by no means uncommon). On the other hand, the frequency of unfounded diagnoses of CD is also on the rise. This reflects a tendency toward exclusively symptomatic diagnosis as well as the growing use of invalidated tests for CD (e.g., the cytotoxic test, the sublingual or subcutaneous provocation/neutralization test, etc.). As a result, public healthcare spending is being increased in several countries (Italy included) by the growing number of prescriptions for gluten-free diets. This editorial discusses the problems of under- and over-diagnosis of CD and provides an algorithm for management of suspected cases designed to minimize both problems with particular importance to morphologic aspects of small bowel (also in electron microscopy), in basal conditions or in gluten-free diets.

High rates of complications and substantial mortality in both types of refractory sprue

INTRODUCTION

Refractory sprue (RS) is a rare malabsorption syndrome defined by persisting small bowel villous atrophy despite a strict gluten-free diet. The clinical picture and long-term outcome of RS is highly variable and is not well described.

AIM

To define underlying and accompanying diseases and clinical outcome in consecutive patients with RS.

PATIENTS AND METHODS

Clinical and histological data from patients with RS at our department were analyzed retrospectively. RS was defined as villous atrophy and malabsorption despite a strict gluten-free diet persisting without improvement for more than 6 months or requiring earlier therapeutic intervention.

RESULTS

Thirty-two patients with RS were identified (23 RS type I, nine RS type II). Follow-up period was 55 (12-372) months. Two patients progressed from RS type I into type II. Thrombembolic events occurred in nine cases, and additional autoimmune diseases were found in 17 patients. Overt intestinal T-cell lymphoma developed in four patients with RS type II. Three patients with RS type II died during the observation period owing to intestinal T-cell lymphoma and four with RS type I owing to infectious complications. Five-year cumulative survival was 90% (95% confidence interval 76-100) in patients with RS type I and higher than in patients with RS type II (53%, 12-94%; P<0.05).

CONCLUSION

RS comprises a very heterogenous group of patients with long-term survival seen even in single patients with RS type II. Overall, survival is shorter in RS type II in comparison with RS type I. Patients with RS type I, however, show similar rates of disease-related complications as well as substantial mortality.

Celiac disease: from oral tolerance to intestinal inflammation, autoimmunity and lymphomagenesis

Celiac disease is a multifactorial disorder and provides a privileged model to decipher how the interplay between environmental and genetic factors can alter mucosal tolerance to a food antigen, lead to chronic intestinal inflammation, and ultimately promote T-cell lymphomagenesis. Here we summarize how HLA-DQ2/8 molecules, the main genetic risk factor for this disease can orchestrate a CD4(+) T-cell adaptive immune response against gluten, and discuss recent data which shed light on the innate and adaptive immune stimuli that collaborate to induce a proinflammatory TH1 response, a massive expansion of intraepithelial lymphocytes, and a cytolytic attack of the epithelium. The intestinal immune response driven in genetically predisposed patients by chronic exposure to gluten emerges as the pathological counterpart of normal acute intestinal responses to intracellular pathogens.

Autoimmune and inflammatory disorders and risk of malignant lymphomas--an update

As specific autoimmune disorders now constitute established risk factors for malignant lymphomas, we describe this association. We review reported risk levels, risk determinants, lymphoma subtypes and biological mechanisms in autoimmunity/inflammation, emphasizing on recent findings. Whilst numerous reports describe average lymphoma risks in large patient groups, there's a recent shift of focus to risk determinants and the role of inflammatory activity. Studies highlight associations with diffuse large B-cell lymphoma, apart from lymphoma development in target organs of inflammation. Future studies of high-risk patient subsets using detailed assessments of autoimmunity/inflammation and lymphoma may give important clues to lymphomagenesis.

Analysis of genomic instability in adult-onset celiac disease patients by microsatellite instability and loss of heterozygosis

BACKGROUND AND AIMS

Malignant complications of celiac disease (CD) include carcinomas and lymphomas. The genetic basis behind cancer development in CD is not known, but acquisition of genetic abnormalities and genomic instability has been involved. The aim of this study was to explore molecular characteristics of genomic instability in CD patients by analyzing microsatellite instability (MSI) and loss of heterozygosis (LOH) with carefully selected microsatellites.

METHODS

We genotyped small bowel biopsies and peripheral blood samples from 20 untreated CD patients using five microsatellites related to MMR genes (panel A), and five repeats associated with tumor suppressor genes, chromosome instability, inflammation, and cancer (panel B).

RESULTS

Genomic instability was found in seven out of 20 (35%) cases at: D5S107, D18S58, GSTP, TP53 or DCC, being TP53 the most frequently affected (five out of seven cases; 71%). Microsatellite alterations were significantly found using panel B markers (P=0.04). No cases with high frequency of MSI and replication error phenotype were detected. Only one case displayed MSI-L alone. Three patients exhibited LOH and three other cases showed LOH with low level of MSI, being classified as having chromosome instability phenotype.

CONCLUSION

Two novel observations were found in this study: first, the finding that non-neoplastic cells from a group of untreated CD patients present genomic instability at nucleotide level; and second, the advantage to use carefully selected microsatellites to identify celiac patients with molecular instability. Our data support the existence of chromosome instability phenotype in CD, suggesting that stable and unstable patients are genomically distinct subtypes that may follow a different evolution.

The presence of small intestinal intraepithelial gamma/delta T-lymphocytes is inversely correlated with lymphoma development in refractory celiac disease

BACKGROUND

In refractory celiac disease (RCD) type II, a phenotypically aberrant (CD7+ CD3- CD4/8-cytoplasmicCD3+) intraepithelial lymphocyte (IEL) population is present, and 50-60% of these patients develop enteropathy-associated T-cell lymphoma (EATL). TCRgammadelta+ IELs play an important role in mucosal repair, homeostasis, and tumor surveillance. Recently, human small intestinal TCRgammadelta+ IELs were shown to have regulatory potential in uncomplicated celiac disease (CD).

AIM

In the present study, we investigated whether TCRgammadelta+ IELs are decreased in RCD II, providing a possible explanation for persisting mucosal damage and inflammation, and the emergence of aberrant T cells with clonal expansion to EATL.

DESIGN AND METHODS

Multiparameter flow cytometric immunophenotyping was performed on IELs isolated from fresh small bowel biopsy specimens of relatively large distinct CD patient and control groups (N = 87).

RESULTS

A significantly lower percentage of TCRgammadelta+ IELs was found in RCD II as compared to all other CD groups. In contrast, in uncomplicated CD patients significantly more TCRgammadelta+ IELs were found than in controls. Overall, there is a clear negative relation between TCRgammadelta+ IELs and aberrant IELs. Interestingly, TCRgammadelta+ IELs increase again in RCD II after effective therapy.

CONCLUSIONS

The observed negative relation between TCRgammadelta+ and aberrant IELs, along with their known regulatory capacity in uncomplicated CD, implies that TCRgammadelta+ IELs may play a crucial role in mucosal repair, regaining homeostasis and possibly even tumor surveillance. These cells may be important markers, in addition to the aberrant T cells, to differentiate between disease categories and to evaluate the effectiveness of therapeutic strategies.

Clinical trial: gluten microchallenge with wheat-based starch hydrolysates in coeliac disease patients - a randomized, double-blind, placebo-controlled study to evaluate safety

BACKGROUND

Wheat-based starch hydrolysates such as glucose syrups, dextrose and maltodextrins are found in more than 50% of European processed food. These products contain low amounts of residual gluten and it has been questioned whether they are safe for coeliac disease patients.

AIM

To investigate whether coeliac disease patients can safely consume wheat-based starch hydrolysate products.

METHODS

This randomized, double-blind, placebo-controlled, prospective follow-up study involved 90 coeliac disease patients in remission randomized to consume glucose syrups, maltodextrins or placebo for 24 weeks. Small bowel mucosal morphology and inflammation, symptoms, coeliac serology and malabsorption laboratory data were evaluated at baseline and at the end of the study.

RESULTS

Daily ingestion of wheat-based starch hydrolysates, glucose syrups and maltodextrins, had no deleterious effect on small-bowel mucosal villous architecture or inflammation in coeliac disease patients when compared to the placebo group. Neither were there any significant differences in gastrointestinal symptoms, serology or malabsorption parameters after 24 weeks.

CONCLUSIONS

Wheat-based starch hydrolysates, glucose syrups and maltodextrins did not have harmful effect on coeliac disease patients. Coeliac patients can thus safely continue to consume these products.

Systematic review: The evidence base for long-term management of coeliac disease

BACKGROUND

While gluten-free diet is an effective treatment for coeliac disease, the need for and goals of long-term management of patients are poorly defined.

AIM

To review systematically the complications and associations of coeliac disease, to identify potential risk factors, to define ways of assessing risk factors and to provide a strategy for management.

METHODS

Review of medical literature from 1975.

RESULTS

There is an increasing list of potential complications and/or conditions associated with coeliac disease, in particular, autoimmune disease, malignancy and bone disease. Risk factors that may predict or influence long-term outcomes include genetic susceptibility, environmental factors predominantly gluten ingestion, persistent small intestinal inflammation/injury and nutritional deficiencies. Genotyping of patients is yet to have an established clinical role in long-term management. Assessment of adherence to the gluten-free diet largely relies upon skilled dietary history, but the ultimate test is duodenal histopathology, which is the only currently established means of assessing healing. Symptoms, serology or other non-invasive means are poor predictors of healing and the likelihood of complications.

CONCLUSION

Evidence (albeit limited) that adherence to a gluten-free diet and mucosal healing prevent and/or ameliorate complications indicates that a planned long-term strategy for follow-up is essential.

Investigation of molecular markers in the diagnosis of refractory coeliac disease in a large patient cohort: Table 1

Aims:

Some patients with coeliac disease, despite strict adherence to a gluten-free diet, continue to have significant symptoms and/or a severe small intestinal histological lesion. The term “refractory coeliac disease” (rCD) is used to describe this condition. The purpose of this study was to investigate the value of tissue molecular markers reported to help in the diagnosis of rCD.

Methods:

Details on 61 patients with suspected rCD were collected. The clinical and laboratory findings in these patients were carefully evaluated, in part to determine whether patients were adhering to a strict gluten-free diet. The co-expression of CD3 and CD8 on intraepithelial lymphocytes was investigated by monoclonal antibody staining of small intestinal biopsy tissue; a finding of less than 50% CD3+ cells co-expressing CD8 was defined as an aberrant phenotype. T cell receptor gene rearrangement was assessed when a sufficient tissue sample was available.

Results:

A diagnosis of rCD was made in 38 patients based on clinical, laboratory and histological data. An aberrant intraepithelial lymphocyte population was found in 20 of these patients and in this group a clonal T cell population was found in five of seven patients tested. In the remaining 18 patients, the CD3/CD8 ratio was normal and two of seven tested had a clonal T cell population. After detailed monitoring, a diagnosis of rCD was excluded in the remaining 23 patients.

Conclusions:

This study supports the use of phenotypic and T cell clonality investigations in identifying patients with true rCD.

Undetected coeliac disease in the elderly: a biopsy-proven population-based study

BACKGROUND

Up to 1% of the population suffer from coeliac disease. Data on the prevalence in elderly people is scant. We hypothesized that they would over time have developed obvious symptoms. Clinically silent or undiagnosed disease would thus be relatively uncommon.

AIMS

To evaluate the prevalence of coeliac disease in elderly people.

METHODS

The study comprised 2815 individuals aged 52-74 years. Clinical cases of coeliac disease were recorded. Sera from all subjects were screened by IgA class tissue transglutaminase antibodies, and seropositive underwent small bowel biopsy.

RESULTS

Coeliac disease was detected in altogether 60 individuals, in 25 (0.89%) on clinical grounds, and screening found in 35 (1.24%) new biopsy-proven cases. Thus, a total prevalence of 2.13% (95% confidence intervals 1.60-2.67%) was reached. Of the screen-detected cases, 15 had symptoms, albeit mostly mild. Two out of the 60 had small bowel T-cell lymphoma and two had gastric cancer. The total frequency of biopsy-proven coeliac disease and seropositive cases without histological confirmation was 2.45% (1.88-3.02%).

CONCLUSION

The prevalence of coeliac disease in elderly people was higher than what has been reported in the population in general. Active case finding by serologic screening is encouraged, since undetected cases may be prone to increased morbidity and mortality.

Defective synthesis or association of T-cell receptor chains underlies loss of surface T-cell receptor-CD3 expression in enteropathy-associated T-cell lymphoma

Enteropathy-associated T-cell lymphoma, an often fatal complication of celiac disease, can result from expansion of aberrant intraepithelial lymphocytes in refractory celiac disease type II (RCD II). Aberrant intraepithelial lymphocytes and lymphoma cells are intracellularly CD3epsilon(+) but lack expression of the T-cell receptor (TCR)-CD3 complex on the cell surface. It is unknown what causes the loss of TCR-CD3 expression. We report the isolation of a cell line from an RCD II patient with the characteristic phenotype of enteropathy-associated T-cell lymphoma. We demonstrate that in this cell line the TCR-alpha and -beta chains as well as the CD3gamma, CD3delta, CD3epsilon, and zeta-chains are present intracellularly and that assembly of the CD3gammaepsilon, CD3deltaepsilon, and zetazeta-dimers is normal. However, dimerization of the TCR chains and proper assembly of the TCR-CD3 complex are defective. On introduction of exogenous TCR-beta chains, but not of TCR-alpha chains, assembly and functional cell surface expression of the TCR-CD3 complex were restored. Defective synthesis of both TCR chains was found to underlie loss of TCR expression in similar cell lines isolated from 2 additional patients. (Pre)malignant transformation in RCD II thus correlates with defective synthesis or defective association of the TCR chains, resulting in loss of surface TCR-CD3 expression.

Is serum citrulline measurement clinically useful in coeliac disease?

Citrulline (CIT), a non-protein amino acid in circulating blood, is almost exclusively contained in the enterocytes of small bowel mucosa and may represent a reliable marker of functioning enterocyte mass. The aim of this study was to evaluate the clinical utility of measuring serum citrulline levels in a group of patients affected by coeliac disease (CD). Fifty healthy volunteers, 21 patients with untreated coeliac disease and 6 patients with refractory coeliac disease took part in the study. Serum citrulline levels and duodenal lesions were evaluated at the time of diagnosis, and after at least 24 months of gluten-free diet. Serum citrulline concentrations were determined by ion exchange chromatography. In comparison to healthy volunteers, serum citrulline concentrations were significantly lower in untreated and refractory coeliac disease patients. No significant difference was found between untreated and refractory coeliac disease patients and between patients with different patterns of clinical presentation or various degrees of duodenal lesions. After a gluten-free diet, the mean of serum citrulline concentration was increased in all but one patient. Although, as expected, serum citrulline levels turned out to be low in coeliac disease, the clinical utility of their measurement is, at least, questionable in this condition.

Anti-calreticulin immunoglobulin A (IgA) antibodies in refractory coeliac disease

Refractory coeliac disease (RCD) is a very rare and dangerous form of CD, in which gluten-free diet loses its therapeutic effect and the damage of intestinal mucosa persists. Because of the adherence to the diet, serological markers of CD [immunoglobulin A (IgA) antibodies against gliadin, tissue transglutaminase (tTG) and endomysium] are often missing in RCD patients. We found substantially elevated levels of IgA anti-calreticulin (CRT) antibodies in the sera of almost all RCD patients tested. These sera were negative for IgA antibodies to gliadin and tTG and only some of them showed IgA antibodies to enterocytes. Analysis of patients' IgA reactivity to CRT fragments (quarters and halves) by Western blotting revealed differences in the specificity of IgA antibodies between RCD and CD patients. We therefore used the Pepscan technique with synthetic overlapping decapeptides of CRT to characterize antigenic epitopes recognized by serum IgA antibodies of RCD patients. Employing this method we demonstrated several dominant antigenic epitopes recognized by IgA antibodies of RCD patients on the CRT molecule. Epitope GVTKAAEKQMKD was recognized predominantly by serum IgA of RCD patients. Our results suggest that testing for serum IgA antibodies against CRT and its selected peptide could be a very useful tool in RCD differential diagnosis.

Humoral immunoreactivity to gliadin and to tissue transglutaminase is present in some patients with multiple myeloma

BACKGROUND

Multiple myeloma (MM) is a clonal B-cell disorder with many immunological disturbances. The aim of this work was to assess whether some of food antigens contribute to the imbalance of immune response by screening the sera of MM patients for their immunoreactivity to food constituent gliadin, to tissue transglutaminase-2 (tTG-2) and to Ro/SSA antigen.Sera from 61 patients with MM in various stages of disease, before, or after some cycles of conventional therapy were analyzed by commercial Binding Site ELISA tests. The control group consisted of 50 healthy volunteers. Statistical analysis of data obtained was performed by Mann Whitney Test.

RESULTS

The higher serum IgA immunoreactivity to gliadin was found in 14/56 patients and in one of control people. The enhanced serum IgG immunoreactivity to gliadin was found in only two of tested patients and in two controls. The enhanced IgA immunoreactivity to tTG-2 was found in 10/49 patients' sera, while 4/45 patients had higher serum IgG immunoreactivity. The enhanced serum IgG immunoreactivity to RoSSA antigen was found in 9/47 analyzed MM patients' sera. Statistical analysis of data obtained revealed that only the levels of anti-tTG-2 IgA immunoreactivity in patients with MM were significantly higher than these obtained in healthy controls (P < 0.02)

CONCLUSION

Data obtained showed the existence of the enhanced serum immunoreactivity to gliadin, tTG-2 and Ro/SSA antigens in some patients with MM. These at least partially could contribute to the immunological imbalance frequently found in this disease.

[Refractory sprue--precursor lesion of enteropathy type T-cell lymphoma--a clinicopathological case report]

INTRODUCTION

Refractory sprue is characterised by distinctive morphologic alterations and the emergence of clonal intraepithelial lymphocytes.

AIM

In this case report the authors emphasize the importance of histopathology in the diagnosis of refractory sprue.

METHODS

The sequential biopsies from this patient have been investigated with routine histology, immunohistochemistry and molecular genetics for T-cell clonality analysis.

RESULTS

The severely cachectic patient presenting with malabsorption syndrome has been diagnosed with celiac disease through a duodenal biopsy, and the CD8 negativity of the intraepithelial lymphocytes suggested the possible diagnosis of refractory sprue. Azathioprine and glucocorticoid therapy was administered due to the failed jejunal feeding and gluten-free diet, resulting in clinically complete, morphologically partial remission. Intestinal T-cell lymphoma developed in the ileocecal region within two years after the first clinical presentation.

DISCUSSION

Refractory sprue and the enteropathy-type T-cell lymphoma constitute a disease spectrum. The reported case shows how a simple method can provide crucial information in the diagnosis of refractory sprue.

Parallels between pathogens and gluten peptides in celiac sprue

Pathogens are exogenous agents capable of causing disease in susceptible organisms. In celiac sprue, a disease triggered by partially hydrolyzed gluten peptides in the small intestine, the offending immunotoxins cannot replicate, but otherwise have many hallmarks of classical pathogens. First, dietary gluten and its peptide metabolites are ubiquitous components of the modern diet, yet only a small, genetically susceptible fraction of the human population contracts celiac sprue. Second, immunotoxic gluten peptides have certain unusual structural features that allow them to survive the harsh proteolytic conditions of the gastrointestinal tract and thereby interact extensively with the mucosal lining of the small intestine. Third, they invade across epithelial barriers intact to access the underlying gut-associated lymphoid tissue. Fourth, they possess recognition sequences for selective modification by an endogenous enzyme, transglutaminase 2, allowing for in situ activation to a more immunotoxic form via host subversion. Fifth, they precipitate a T cell–mediated immune reaction comprising both innate and adaptive responses that causes chronic inflammation of the small intestine. Sixth, complete elimination of immunotoxic gluten peptides from the celiac diet results in remission, whereas reintroduction of gluten in the diet causes relapse. Therefore, in analogy with antibiotics, orally administered proteases that reduce the host's exposure to the immunotoxin by accelerating gluten peptide destruction have considerable therapeutic potential. Last but not least, notwithstanding the power of in vitro methods to reconstitute the essence of the immune response to gluten in a celiac patient, animal models for the disease, while elusive, are likely to yield fundamentally new systems-level insights.

Flow cytometric analysis of intestinal intraepithelial lymphocytes in the diagnosis of refractory celiac sprue

The etiology of refractory celiac sprue (RCS) is unclear. In a high proportion of cases, the clonal nature of intestinal intraepithelial lymphocytes (IEL) can be demonstrated and a pathogenetic implication of intestinal IEL has been postulated. The prognosis of this subgroup of RCS is poor, with a high risk to develop an overt lymphoma and uncontrolled malabsorption despite steroid/immunosuppressive therapy. Cases with a relatively indolent clinical course, however, exist and their early diagnosis may be difficult. To gain insight into the pathogenic implication of intestinal IEL in refractory celiac sprue, we have performed an extensive phenotypic and functional characterization of clonal intestinal IEL in a patient with an indolent form of refractory celiac sprue, using multiparametric flow cytometry. The abnormal lymphocyte infiltrate lacked surface membrane expression of CD3/T-cell receptor (TCR) complexes (TCR(-), CD4(-), CD8(-), sCD3(-)), but contained intracellular CD3(epsilon) (CyCD3(+)) and surface CD103(+) and CD7(+). In particular, these cells showed a unique spontaneous ex-vivo cytokine secretion profile with an increased percentage of CD3(-) IEL containing TNF-alpha and IL-10, in the absence of IL-2, IL-4 and IFN-gamma. Altogether our results suggest that flow cytometry immunophenotyping of intestinal IEL, in cases suspected of celiac disease and their complicated forms, could be of great help in the correct diagnosis of RCS and the understanding of the immunopathogenic mechanisms of the disease and their clinical and/or therapeutical implications.

Extranodal lymphoma

Lymphomas arising in extranodal sites are intriguing. The types of lymphomas encountered vary widely from one extranodal site to another. For many types of extranodal lymphomas, there are distinctive clinicopathologic features, sometimes including association with an underlying immunodeficiency syndrome, autoimmune disease, infection, or other immunologic disorder, or a predilection to affect patients of certain ethnic origins. Presented below is a review of lymphomas that are encountered most often in extranodal sites.