Refractory celiac disease

Novel Drug Therapeutics in Celiac Disease: A Pipeline Review

Celiac disease (CeD) is a chronic, autoimmune systemic disorder triggered by the ingestion of gluten, a protein found in foods such as wheat, rye, and barley. The only effective treatment for CeD is complete removal of gluten from the diet. A strict gluten-free diet (GFD) results in symptomatic, serologic, and histologic remission in most patients. However, GFD may fail to induce clinical or histologic improvement and some patients may alternatively have difficulty strictly adhering to the GFD for other reasons. Despite this, there are currently no FDA-approved drugs for the treatment of CeD. The complex pathogenic process of CeD is becoming increasingly studied and better understood, enabling the identification of various targets for future therapies. Mechanisms under evaluation include probiotics, digestion of peptides, gluten sensitization, tight junction modulation, deamidation, and immune targets. Multiple investigational drugs are in the pipeline, and several drug candidates have entered late-phase clinical trials. Indeed, current and future studies are needed to target specific etiological mechanisms and provide an alternative to GFD alone. This review provides a broad overview of the various investigative treatment approaches for CeD, summarizing the latest progress in the pipeline.

DNA damage, oxidative stress, and inflammation in children with celiac disease

The objective of this study was to evaluate the level of genomic instability in patients with celiac disease and to establish a relationship between inflammation, oxidative stress, and DNA damage in these patients. Myeloperoxidase (MPO) activity, adenosine deaminase, nitric oxide (NOx), thiobarbituric acid, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and DNA damage were evaluated in peripheral blood samples from 47 celiac disease patients and 31 controls. Patients with celiac disease presented higher levels of DNA damage in comparison to controls (p=0.023). This difference was also observed for markers of oxidative stress, such as CAT (p=0.011) and SOD (p=0.013), and inflammatory markers such as MPO (p < 0.001) and NOx (p=0.009). Positive correlations were found between DNA damage levels and the values of CAT (r=0.405; p=0.009) and SOD (r=0.516; p < 0.001). Positive correlations were also found between GPx and NOx (r=0.349; p=0.030) and MPO and NOx (r=0.239; p=0.039). CAT and NOx showed a negative correlation (r= −0.315; p=0.042). In conclusion, intestinal inflammation can have systemic effects, causing an imbalance between oxidant and antioxidant markers, which may promote increased levels of DNA damage.

The Influence of Small Intestinal Bacterial Overgrowth in Digestive and Extra-Intestinal Disorders

Small intestinal bacterial overgrowth (SIBO) is a condition hallmarked by an increase in the concentration of colonic-type bacteria in the small bowel. Watery diarrhea, bloating, abdominal pain and distension are the most common clinical manifestations. Additionally, malnutrition and vitamin (B12, D, A, and E) as well as minerals (iron and calcium) deficiency may be present. SIBO may mask or worsen the history of some diseases (celiac disease, irritable bowel disease), may be more common in some extra-intestinal disorders (scleroderma, obesity), or could even represent a pathogenetic link with some diseases, in which a perturbation of intestinal microbiota may be involved. On these bases, we performed a review to explore the multiple links between SIBO and digestive and extra-intestinal diseases.

Celiac Disease and Its Role in the Development of Metabolic Bone Disease

Celiac disease (CD) is an immune-mediated enteropathy that occurs in genetically susceptible hosts with the ingestion of gluten-containing products. Ongoing gluten consumption leads to intestinal damage, characterized by villous blunting and increased intraepithelial lymphocytes, resulting in malabsorption. Pertinent to the development of bone disease, malabsorption of calcium and vitamin D leads to secondary hyperparathyroidism and metabolic bone disease among individuals with CD. In this article, we review the pathogenesis of CD and the effects of malabsorption on bone health. Imbalances in bone resorption and formation particularly in individuals with CD and persistent disease activity ultimately lead to a state of bone loss and impaired mineralization. Initiation of a gluten-free diet is critical in the management of CD-related metabolic bone disease, demonstrating improvements in bone mineral density within the first year of dietary adherence.

Multifactorial Etiology of Anemia in Celiac Disease and Effect of Gluten-Free Diet: A Comprehensive Review

Celiac disease (CD) is a multisystemic disorder with different clinical expressions, from malabsorption with diarrhea, anemia, and nutritional compromise to extraintestinal manifestations. Anemia might be the only clinical expression of the disease, and iron deficiency anemia is considered one of the most frequent extraintestinal clinical manifestations of CD. Therefore, CD should be suspected in the presence of anemia without a known etiology. Assessment of tissue anti-transglutaminase and anti-endomysial antibodies are indicated in these cases and, if positive, digestive endoscopy and intestinal biopsy should be performed. Anemia in CD has a multifactorial pathogenesis and, although it is frequently a consequence of iron deficiency, it can be caused by deficiencies of folate or vitamin B₁₂, or by blood loss or by its association with inflammatory bowel disease (IBD) or other associated diseases. The association between CD and IBD should be considered during anemia treatment in patients with IBD, because the similarity of symptoms could delay the diagnosis. Vitamin B₁₂ deficiency is common in CD and may be responsible for anemia and peripheral myeloneuropathy. Folate deficiency is a well-known cause of anemia in adults, but there is little information in children with CD; it is still unknown if anemia is a symptom of the most typical CD in adult patients either by predisposition due to the fact of age or because biochemical and clinical manifestations take longer to appear.

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.

Diagnosis of chronic anaemia in gastrointestinal disorders: A guideline by the Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO) and the Italian Society of Paediatric Gastroenterology Hepatology and Nutrition (SIGENP)

Anaemia is a common pathologic condition, present in almost 5% of the adult population. Iron deficiency is the most common cause; other mechanisms can be involved, making anaemia a multi-factorial disorder in most cases. Anaemia being a frequent manifestation in the diseases of the gastrointestinal tract, patients are often referred to gastroenterologists. Furthermore, upper and lower endoscopy and enteroscopy are pivotal to the diagnostic roadmap of anaemia. In spite of its relevance in the daily clinical practice, there is a limited number of gastroenterological guidelines dedicated to the diagnosis of anaemia. For this reason, the Italian Association of Hospital Gastroenterologists and Endoscopists and the Italian Society of Paediatric Gastroenterology, Hepatology and Nutrition commissioned a panel of experts to prepare a specific guideline on anaemia and its diagnostic roadmap in the gastroenterological scenario. The panel also discussed about the potential involvement of gastroenterologists and endoscopists in the management of patients with anaemia, with particular attention to the correct use of investigations. The panel paid particular attention to practical issues with the aim to support gastroenterologists in their clinical practice when dealing with patients with anaemia.

Translational Chemistry Meets Gluten-Related Disorders

Gluten‐related disorders are a complex group of diseases that involve the activation of the immune system triggered by the ingestion of gluten. Among these, celiac disease, with a prevalence of 1 %, is the most investigated, but recently, a new pathology, named nonceliac gluten sensitivity, was reported with a general prevalence of 7 %. Finally, there other less‐prevalent gluten‐related diseases such as wheat allergy, gluten ataxia, and dermatitis herpetiformis (with an overall prevalence of less than 0.1 %). As mentioned, the common molecular trigger is gluten, a complex mixture of storage proteins present in wheat, barley, and a variety of oats that are not fully degraded by humans. The most‐studied protein related to disease is gliadin, present in wheat, which possesses in its sequence many pathological fragments. Despite a lot of effort to treat these disorders, the only effective method is a long‐life gluten‐free diet. This Review summarizes the actual knowledge of gluten‐related disorders from a translational chemistry point of view. We discuss what is currently known from the literature about the interaction of gluten with the gut and the critical host responses it evokes and, finally, connect them to our current and novel molecular understanding of the supramolecular organization of gliadin and the 33‐mer gliadin peptide fragment under physiological conditions.

Oral nucleic acid therapy using multicompartmental delivery systems

Nucleic acid-based therapeutics has the potential for treating numerous diseases by correcting abnormal expression of specific genes. Lack of safe and efficacious delivery strategies poses a major obstacle limiting clinical advancement of nucleic acid therapeutics. Oral route of drug administration has greater delivery challenges, because the administered genes or oligonucleotides have to bypass degrading environment of the gastrointestinal (GI) tract in addition to overcoming other cellular barriers preventing nucleic acid delivery. For efficient oral nucleic acid delivery, vector should be such that it can protect encapsulated material during transit through the GI tract, facilitate efficient uptake and intracellular trafficking at desired target sites, along with being safe and well tolerated. In this review, we have discussed multicompartmental systems for overcoming extracellular and intracellular barriers to oral delivery of nucleic acids. A nanoparticles-in-microsphere oral system-based multicompartmental system was developed and tested for in vivo gene and small interfering RNA delivery for treating colitis in mice. This system has shown efficient transgene expression or gene silencing when delivered orally along with favorable downstream anti-inflammatory effects, when tested in a mouse model of intestinal bowel disease. WIREs Nanomed Nanobiotechnol 2018, 10:e1478. doi: 10.1002/wnan.1478 This article is categorized under: Biology-Inspired Nanomaterials > Nucleic Acid-Based Structures Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Multimodal Immunosuppressant Therapy in Steroid-Refractory Common Variable Immunodeficiency Sprue: A Case Report Complicating Cytomegalovirus Infection

Immunodeficient patients can develop malabsorption, mimicking celiac disease clinically and histologically. Such individuals may also occasionally require immunosup pressive therapy for autoimmune disorders. We have identified a patient with common variable immunodeficiency (CVID)-associated sprue complicated by duodenal cytomegalovirus (CMV) infection following corticosteroid and ancillary immunomodulatory therapy. Ganciclovir and a modification of the immunosuppressant regimen improved both clinical symptoms and villous atrophy. To our knowledge, this is original documentation of duodenal CMV infection secondary to immunomodulatory therapy for steroid-refractory CVID-sprue.

Gliadin-Specific T-Cells Mobilized in the Peripheral Blood of Coeliac Patients by Short Oral Gluten Challenge: Clinical Applications

Celiac disease (CD) is a common lifelong food intolerance triggered by dietary gluten affecting 1% of the general population. Gliadin-specific T-cell lines and T-cell clones obtained from intestinal biopsies have provided great support in the investigation of immuno-pathogenesis of CD. In the early 2000 a new in vivo, less invasive, approach was established aimed to evaluate the adaptive gliadin-specific T-cell response in peripheral blood of celiac patients on a gluten free diet. In fact, it has been demonstrated that three days of ingestion of wheat-containing food induces the mobilization of memory T lymphocytes reactive against gliadin from gut-associated lymphoid tissue into peripheral blood of CD patients. Such antigen-specific T-cells releasing interferon-γ can be transiently detected by using the enzyme-linked immunospot (ELISPOT) assays or by flow cytometry tetramer technology. This paper discusses the suitability of this in vivo tool to investigate the repertoire of gluten pathogenic peptides, to support CD diagnosis, and to assess the efficacy of novel therapeutic strategies. A systematic review of all potential applications of short oral gluten challenge is provided.

Pathologic bone alterations in celiac disease: etiology, epidemiology, and treatment

Low bone mineral density (BMD), osteopenia, and osteoporosis are frequent complications of celiac disease (CD). The etiology of pathologic bone alterations in CD is multifactorial; however, two main mechanisms are involved: intestinal malabsorption and chronic inflammation. A strict gluten-free diet (GFD) is thought to be the only effective treatment for CD; but treating bone complications related to CD remains complex. The objective of this review is to elucidate the bones problems related to CD and to increase awareness of osteoporosis development, considered as a sign of atypical CD presentation. Currently, a question of whether GFD alone is an effective treatment to correct the bone alterations in patients with CD is under debate. This review presents factors contributing to pathologic bone derangement, recent research on the epidemiology of low BMD, osteoporosis, and fractures, and the treatment of bone problems in patients with CD. The roles of calcium and transport mechanisms are additionally presented.

Assessment of the response to gluten-free diet in an Iraqi population with coeliac disease. A histological and serological follow-up study

INTRODUCTION

Coeliac disease (CD) is a common diagnosis among children and adults in Iraq; however, removal of gluten from the diet is essential for patients with CD. The aim of this study, the first such study in Iraq, was to assess the serological and histological recovery profiles of coeliac patients, in both children and adults groups after commencing a gluten-free diet (GFD) for at least 1 year ± 1 month.

MATERIAL AND METHODS

The study group comprised 78 proved coeliac patients (46 children and 32 adults, median age: 15 years, range: 1-66 years) who all agreed to undergo endoscopy in addition to serological assessment before and after treatment. The duodenal biopsies were interpreted histologically according to modified Marsh criteria and the sera were tested for anti-gliadin antibody (AGA), endomysium antibody (EMA) and anti-tissue transglutaminase antibody (tTG).

RESULTS

Complete histological remission was seen in 29 (63.1%) of 46 treated children CD patients, while only 5 (10.9%) showed Marsh IIIa changes compared with 11 (24%) before GFD. Similarly none of the 32 adults after GFD showed Marsh IIIb and Marsh IIIc compared with 46.9% and 28.1% before treatment respectively (p = 001). Meanwhile, there was strongly significant reduction in AGA, EMA, and tTG antibodies levels (p = 0.00001) following GFD.

CONCLUSIONS

Repeating the duodenal biopsy 1 year ±1 month after diagnosis and starting a GFD supports the routine measurement of using histological findings as a gold standard test to confirm recovery of Iraqi CD patients along with using known coeliac serology antibodies.

Glutathione redox cycle in small intestinal mucosa and peripheral blood of pediatric celiac disease patients

The celiac disease is an autoimmune gastrointestinal disorder caused by gluten from wheat, rye or barley. In genetically predisposed persons, gluten induces the immune-mediated inflammation of small intestinal mucosa. Histological lesions include intraepithelial lymphocytosis, crypt hypertrophy and villous atrophy, resulting in malabsorption of micro- and macronutrients. The only treatment for celiac patients is a permanent gluten-free diet (GFD). Reactive oxygen species (ROS) and oxidative stress are strongly associated with the celiac disease. Glutathione (GSH) is a main detoxifier of endogenous and exogenous ROS in the intestine. In order to explain the role of glutathione redox cycle in celiac patients, we examined the activities of GSH-related antioxidant (AO) enzymes glutathione peroxidase (GPx) and glutathione reductase (GR), as well as the concentration of GSH in small intestinal biopsies and peripheral blood of children affected by the celiac disease. The concentration of lipid hydroperoxides (LOOH) as markers of oxidative damage was measured in the same samples. The results clearly demonstrate a significant malfunction of GSH redox cycle with a concomitant decrease in the capacity to regenerate GSH and detoxify LOOH in celiac patients, even after several years of GFD. The oral administration of GSH and a diet rich in natural antioxidants, as well as appropriate dietary supplements, could be of great benefit to the patients.

Celiac disease

Celiac disease is common, affecting approximately 1 in 100 people, yet it remains underdiagnosed. This article reviews our current understanding of celiac disease, diagnosis, and common pitfalls. Although the cornerstone of treatment is a gluten-free diet, some patients may still have persisting symptoms and warrant further investigations.

Recent advances in the development of new treatments for celiac disease

INTRODUCTION

Celiac disease is a common autoimmune condition induced by dietary gluten in genetically susceptible individuals. So far, the only available treatment for the disorder is a lifelong strict gluten-free diet, because of which small intestinal histological changes recover and symptoms disappear. However, gluten-free dieting is restrictive, and nutritionally less than optimal, and gluten is difficult to avoid.

AREAS COVERED

With improving insight into the pathogenesis of celiac disease, several possible drug targets have been suggested. The new strategies include degradation of gluten intraluminally, reduction of mucosal permeability, inhibition of the transglutaminase 2 enzyme, blocking antigen presentation by HLA-DQ2 or HLA-DQ8, modulation of the immune responses of many cytokines, and vaccination.

EXPERT OPINION

Non-dietary treatment options are warranted either as adjunctive therapy together with dieting or to replace the gluten-free diet. The key question is whether the envisaged novel drug is able to prevent gluten-induced small intestinal mucosal injury as efficiently as a strict gluten-free diet, alleviating symptoms and signs of the disease. Furthermore, the gluten dose that can be detoxified, if at all, must be established. The new drug should also be as safe as dietary treatment. Several novel treatment options are under development.

A review of rifaximin and bacterial overgrowth in poorly responsive celiac disease

A proportion of patients with celiac disease have a poor response to a gluten-free diet, which may be due to small-intestinal bacterial overgrowth (SIBO). Treatment with rifaximin is often used in the clinical setting, but there is limited literature to support this practice. In addition, challenges in the diagnosis of SIBO confound response interpretation. Our recent placebo-controlled trial did not demonstrate any improvement in gastrointestinal symptoms after treatment with rifaximin and casts doubt on the utility of lactulose-hydrogen breath testing for SIBO in this population.

Adult coeliac disease in Ireland: a case series

BACKGROUND

The clinical spectrum of adult coeliac disease (ACD) is varied with limited Irish data.

AIMS AND OBJECTIVES

The aim of this study was to analyse the presenting symptoms, associated conditions and complications in a consecutive series of patients with ACD.

METHODS

Data were obtained from database on patients with ACD between 1988 and 2004.

RESULTS

One hundred and six patients (69F:37M, mean age: 46, range: 23-95 years) were included. The modes of presentation were diarrhoea in 44 patients (45%), weight loss in 41 (42%), anaemia in 37 (38%), abdominal pain in 15 (15%), fatigue in 8 (8%), hypocalcaemia in 4 (4%) and steatorrhoea in 4 (4%). Associated conditions included thyroid disorders in 7 patients (7%), bipolar affective disorder in 4 (4%), major depression in 3 (3%), rheumatoid disease in 3 (3%), inflammatory bowel disease in 4 (4%) and type I diabetes mellitus in 2 (2%). Malignancy emerged as a major complication in 15 patients (15%)

CONCLUSION

The presenting features of ACD are diverse and associated with high risk of malignancy.

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.

[Enteropathy-associated T-cell lymphoma: a diagnostic challenge]

Diagnosis of refractory celiac disease (CD) is based on exclusion of other disorders, persistence of malabsorptive symptoms and villous atrophy, despite a strict gluten-free diet for at least 6-12 months. Detection of alterations in the intraepithelial lymphocyte population is crucial for diagnosis. A subgroup of patients with refractory CD may develop severe complications such as enteropathy-associated T cell lymphoma (EATL). We present the case of a patient with longstanding silent CD who developed EALT, highlighting the challenge posed by the diagnosis and treatment of this entity.

Risk of morbidity in contemporary celiac disease

Celiac disease is one of the most common chronic diseases encountered in the Western world with a serological prevalence of approximately 1%. Since it is so common, much comorbidity will occur either as associations or simply by chance, or as complications of the disorder. Many of the published studies purporting to establish the frequency of these occurrences have been limited by factors such as the source and number of patients considered, choice of control groups and ascertainment bias. Recent epidemiological studies have attempted to minimize these sources of error and provide more reliable information. Autoimmune diseases constitute clinically important associations, of which Type 1 diabetes mellitus and thyroid disorders are the most important. Several liver disorders, including primary biliary cirrhosis and primary sclerosing cholangitis, are also associated. The frequency of malignant complications of celiac disease is much lower than earlier studies have indicated, with lymphoma increased by approximately fivefold and the absolute number of tumors is small. The increase in fracture risk in celiac disease is only modest. Although neurological and psychiatric conditions affect celiac patients, no disorder specifically associated with celiac disease has been identified. Reproductive problems have been overexaggerated. It is important that these co-morbidities are recognized because if not, symptoms will be falsely attributed to deliberate or inadvertent ingestion of gluten, rather than prompt a search for a second diagnosis. Furthermore, in a patient with an established diagnosis that is considered falsely to account for the whole clinical picture, celiac disease is likely to remain undetected.

Flow cytometry of intestinal intraepithelial lymphocytes in celiac disease

This article reviews the multiple uses of flow cytometry in the diagnosis, monitoring and research of celiac disease, the most prevalent chronic autoimmune gastrointestinal disease. The phenotyping of intraepithelial lymphocytes (IELs) is of clinical relevance in the diagnosis of the disease given the characteristic features of elevated CD3+ IELs (αβ and γδ TcR) and the decrease in CD3- IELs. IEL biomarkers are also useful in the assessment of the response to the gluten-free diet and, importantly, in the diagnosis of the severe complications of celiac disease: refractory celiac disease and enteropathy-associated T-cell lymphoma. Novel applications of flow cytometry for the detection of anti-transglutaminase antibodies (a validated biomarker of celiac disease) and of gluten (the triggering antigen of the autoimmune process) are also discussed. The assessment of diagnostic and prognostic biomarkers by flow cytometry in celiac disease is performed routinely in a growing number of centers and it is an example of the versatility of this technique and its applicability to the research and clinical study of solid tissues.

Visualization of transepithelial passage of the immunogenic 33-residue peptide from alpha-2 gliadin in gluten-sensitive macaques

Background

Based on clinical, histopathological and serological similarities to human celiac disease (CD), we recently established the rhesus macaque model of gluten sensitivity. In this study, we further characterized this condition based on presence of anti-tissue transglutaminase 2 (TG2) antibodies, increased intestinal permeability and transepithelial transport of a proteolytically resistant, immunotoxic, 33-residue peptide from α₂-gliadin in the distal duodenum of gluten-sensitive macaques.

Methodology/Principal Findings

Six rhesus macaques were selected for study from a pool of 500, including two healthy controls and four gluten-sensitive animals with elevated anti-gliadin or anti-TG2 antibodies as well as history of non-infectious chronic diarrhea. Pediatric endoscope-guided pinch biopsies were collected from each animal's distal duodenum following administration of a gluten-containing diet (GD) and again after remission by gluten-free diet (GFD). Control biopsies always showed normal villous architecture, whereas gluten-sensitive animals on GD exhibited histopathology ranging from mild lymphocytic infiltration to villous atrophy, typical of human CD. Immunofluorescent microscopic analysis of biopsies revealed IgG+ and IgA+ plasma-like cells producing antibodies that colocalized with TG2 in gluten-sensitive macaques only. Following instillation in vivo, the Cy-3-labeled 33-residue gluten peptide colocalized with the brush border protein villin in all animals. In a substantially enteropathic macaque with “leaky” duodenum, the peptide penetrated beneath the epithelium into the lamina propria.

Conclusions/Significance

The rhesus macaque model of gluten sensitivity not only resembles the histopathology of CD but it also may provide a model for studying intestinal permeability in states of epithelial integrity and disrepair.

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.

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.

Antioxidant status and lipid peroxidation in small intestinal mucosa of children with celiac disease

OBJECTIVE

To explain the role of oxidative stress in the pathology of celiac disease.

DESIGN AND METHODS

The activities of antioxidant enzymes and the levels of glutathione and lipid hydroperoxides were measured in the samples of small intestinal biopsies from 39 children with different forms of the disease and in 19 control subjects.

RESULTS

The activities of analyzed enzymes varied significantly between the examined groups. An increase in the activities of superoxide dismutase was observed in patients with active and silent celiac disease, while the activities of glutathione peroxidase and glutathione reductase and the glutathione content were significantly reduced. The level of lipid hydroperoxides was significantly elevated in these groups.

CONCLUSIONS

Oxidative stress is an important factor in the pathogenesis of celiac disease. The antioxidant capacity of celiac patients is significantly reduced, mostly by a depletion of glutathione. Natural antioxidants and appropriate dietary supplements could be important complements to the classic therapy of celiac disease.

Arachidonic acid metabolites follow the preferential course of cyclooxygenase pathway for the basal tone in the internal anal sphincter

Present studies determined the roles of the cyclooxygenase (COX) versus the lipoxygenase (LO) pathways in the metabolic pathway of arachidonic acid (AA) in the internal anal sphincter (IAS) tone. Studies were performed in the rat IAS versus the nontonic rectal smooth muscle (RSM). Indomethacin, the dual COX inhibitor, but not nordihydroguaiaretic acid (NDGA), the LO inhibitor, produced a precipitous decrease in the IAS tone. However, when added in the background of indomethacin, NDGA caused significant reversal of the IAS tone. These inhibitors had no significant effect on the RSM. To follow the significance of COX versus LO pathways, we examined the effects of AA and its metabolites. In the IAS, AA caused an increase in the IAS tone (Emax=38.8+/-3.0% and pEC50=3.4+/-0.1). In the RSM, AA was significantly less efficacious and potent (Emax=11.3+/-3.5% and pEC50=2.2+/-0.3). The AA metabolites (via COXs) PGF2alpha and U-46619 (a stable analog of thromboxane A2) produced increases in the IAS tone and force in the RSM. Conversely, AA metabolites (via 5-LO) lipoxin A4, 5-HETE, and leukotriene C4 decreased the IAS tone. Finally, the contractile effects of AA in the IAS were selectively attenuated by the COX-1 but not the COX-2 inhibitor. Collectively, the specific effects of AA and the COX inhibitor, the Western blot and RT-PCR analyses showing specifically higher levels of COX-1, suggest a preferential role of the COX (specifically COX-1) pathway versus the LO in the regulation of the IAS tone.

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.

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.

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.

[Primary T-cell lymphoma of the small bowel]

Primary malignancies in the small intestine are relatively rare. There are no specific methods to find these tumours in early stage. The authors report a case of a primary T-cell lymphoma in the small bowel that caused diagnostic challenges. A 66-year-old woman presenting with abdominal pain and and a palpable mass in the left upper quadrant of her abdomen was admitted into the hospital. Blood tests, endoscopic examinations, ultrasonography and CT scan could not reveal a definitive diagnosis. While a small bowel follow through examination demonstrated an entero-enteral fistula, its exact position could not have been determined. Consequently, an exploratory laparotomy was carried out, and a tumour was found involving the small bowel loops. The involved portion of the small intestine (with the fistula) was resected, and a side-to-side small bowel anastomosis was performed. Histological and immunohistochemical analyses revealed a primary T-cell lymphoma of the small bowel. There was no evidence of metastatic disease at the time of surgery. The patient received adjuvant chemotherapy, but three months later multiple lung metastases were detected. Small bowel malignant tumours cause significant diagnostic difficulties. Therefore, diagnosis and adequate treatment are usually delayed for some weeks. In the future, capsule endoscopy could help in the diagnostic work-up. Nevertheless, surgical exploration and resection of the tumour will be necessary for the correct diagnosis and treatment.

Refractory celiac disease

Celiac disease (CD) is a small intestinal inflammatory disorder characterized by an immune-mediated enteropathy triggered by the ingestion of wheat gluten or related rye and barley proteins in genetically predisposed individuals carrying the human leukocyte antigens (HLA)-DQ2 or -DQ8. Nonresponsive CD (NRCD) is a clinical diagnosis defined by the persistence of signs, symptoms, and/or laboratory abnormalities typical of CD despite adherence to a gluten-free diet for at least 6 months. One cause for NRCD is refractory CD (RCD), defined as the persistence of severe villous atrophy on small intestinal biopsy despite strict gluten withdrawal for at least 6 months with no evidence of other pathology. Although rare, RCD should be suspected in individuals with an established diagnosis of CD who fail to respond primarily or secondarily to a strict gluten-free diet, particularly if they manifest significant weight loss. A thorough evaluation must be performed to distinguish RCD from other causes of NRCD. RCD may be categorized into type I or type II. Type I RCD has a more favorable prognosis compared with type II and can often be managed with nutritional supplementation and possibly low level immunosuppressive therapy. Type II RCD carries a poor prognosis and is more likely to progress to life-threatening malnutrition or intestinal T-cell lymphoma. Immunosuppressive agents and, more recently, autologous stem cell transplant have been used to treat type II RCD.

Clinical symptoms in celiac patients on a gluten-free diet

OBJECTIVE

Persistent villous atrophy in patients with celiac disease (CD) on a gluten-free diet (GFD) is reported with increasing frequency. The aim of this study was to evaluate a possible association between persistent damage of the villi and "atypical" gastrointestinal symptoms in CD patients on a GFD.

MATERIAL AND METHODS

Sixty-nine CD patients on a GFD were divided into two groups: Group A included 42 patients (6 M, 36 F, age range 17-62 years) undergoing esophagogastroduodenoscopies (EGDs) due to the presence of symptoms; Group B included 27 control patients (6 M, 21 F, age range 24-71 years) who were asymptomatic at the time of the study. Both groups underwent EGDs and a duodenal histologic study.

RESULTS

Persistent endoscopic lesions were more frequent in Group A (30/42) than in Group B (12/27; p=0.01). Villous atrophy was significantly more frequent in Group A than in Group B: 85% versus 33% (p<0.0001; odds ratio (OR)=12; 95% CI 3.7-38.9). Gastrointestinal symptoms in the Group A patients were different from those present at CD diagnosis: anemia/diarrhea/weight loss in 6 cases; gastroesophageal reflux disease (GERD)-like symptoms in 12 cases; abdominal pain/constipation in 24 cases. In Group A there was no difference in gender distribution, age and duration of GFD between subjects with normal villi and those with persistent partial villous atrophy. Patients with persistent symptoms showed a higher intraepithelial eosinophil count (p=0.005) than the asymptomatic patients (p=0.01).

CONCLUSIONS

Persistent intestinal villous atrophy in CD patients on a GFD is associated with gastrointestinal symptoms considered "atypical" for CD and not present at CD diagnosis.

Role of phospholipase A2 (group I secreted) in the genesis of basal tone in the internal anal sphincter smooth muscle

The role of phospholipase A(2) (PLA(2)) in the genesis of basal tone in the internal anal sphincter (IAS) is not known. We determined the effects of PLA(2) and inhibitors on the basal tone and intraluminal pressures (IASP) in the rat IAS vs. rectal smooth muscles (RSM). In addition, we determined the correlations between the IAS tone, PLA(2) levels, and the actual enzymatic activity. Inhibition of PLA(2) by 4-bromophenacyl bromide (universal inhibitor of PLA(2)) and MJ33 [selective inhibitor of secreted isoform of PLA(2) (sPLA(2))] caused concentration-dependent decrease in the IAS tone and in the IASP. Maximal decreases in the IAS tone and IASP by 4-bromophenacyl bromide and MJ33 were 58.8 +/- 6.9 and 51.5 +/- 6.3%, and 66.7 +/- 5.1 and 79.8 +/- 8.2%, respectively. The sPLA(2) inhibitors were approximately 100 times more potent in decreasing the IASP than the mean blood pressure. Conversely, the selective inhibitors of the cytosolic and calcium-independent PLA(2) arachidonyl trifluoromethyl ketone and bromoenol lactone, respectively, produced no significant effect. The IAS had characteristically higher levels of sPLA(2) activity (26.5 +/- 4.9 micromol.min(-1).ml(-1)) vs. the RSM (3.2 +/- 0.4 micromol.min(-1).ml(-1)), and higher levels of sPLA(2) as shown by Western blot and RT-PCR. Interestingly, administration of sPLA(2) transformed RSM into the tonic smooth muscle like that of the IAS: it developed basal tone and relaxed in response to the electrical field stimulation. From the present data, we conclude that sPLA(2) plays a critical role in the genesis of tone in the IAS. PLA(2) inhibitors may provide potential therapeutic target for treating anorectal motility disorders.

Budesonide in the treatment of refractory celiac disease

OBJECTIVE

Corticosteroids are used in patients with refractory celiac disease. In order to minimize their systemic side effects, we assessed the role of a locally active sustained release corticosteroid with minimal systemic bioavailability in patients with refractory celiac disease in an open labeled noncontrolled study.

METHODS

Patients who received budesonide for refractory celiac disease were classified according to whether they were primarily or secondarily unresponsive to the diet, and whether they had a polyclonal (type I) or clonal (type II) expansion of intraepithelial lymphocytes. The response to budesonide was assessed globally and by reduction in bowel movements.

RESULTS

Patients (N = 29, 72% female) received budesonide for a mean of 6.7 +/- 8.5 months, 5 patients (18%) had type II disease (clonal T-cell population); 76% responded to the medication, 55% completely. Response occurred when budesonide was used alone or with oral corticosteroids and/or azathioprine. There was an objective improvement in the number of bowel movements in those that responded. Response occurred in those with either primary or secondary refractory disease and in those with type II disease, irrespective of the presence of microscopic colitis (N = 7). There was no improvement in the duodenal biopsy over the study period and there were no side effects of budesonide.

CONCLUSIONS

Budesonide may be of value in the management of refractory celiac disease.

Cellular regulation of basal tone in internal anal sphincter smooth muscle by RhoA/ROCK

Sustained contractions of smooth muscle cells (SMC) maintain basal tone in the internal anal sphincter (IAS). To examine the molecular bases for the myogenic tone in the IAS, the present studies focused on the role of RhoA/ROCK in the SMC isolated from the IAS vs. the adjoining phasic tissues of the rectal smooth muscle (RSM) and anococcygeus smooth muscle (ASM) of rat. We also compared cellular distribution of RhoA/ROCK, levels of RhoA-GTP, RhoA-Rho guanine nucleotide dissociation inhibitor (GDI) complex formation, levels of p(Thr696)-MYPT1, and SMC relaxation caused by RhoA inhibition. Levels of RhoA/ROCK were higher at the cell membrane in the IAS SMC compared with those from the RSM and ASM. C3 exoenzyme (RhoA inhibitor) and Y 27632 (ROCK inhibitor) caused a concentration-dependent relaxation of the IAS SMC. In addition, active ROCK-II (primary isoform of ROCK in SMC) caused further shortening in the IAS SMC. C3 exoenzyme increased RhoA-RhoGDI binding and reduced the levels of RhoA-GTP and p(Thr696)-MYPT1. ROCK inhibitor attenuated PKC-induced contractions in IAS SMC. Conversely, a PKC inhibitor (Gö 6850, which causes partial relaxation of the SMC) had no significant effect on ROCK-II-induced contractions. Further experiments showed the highest levels of RhoA, active form of RhoA (RhoA-GTP), ROCK-II, 20-kDa myosin regulatory light chain (MLC(20)), phospho-MYPT1, and phospho-MLC(20) in the IAS vs. RSM and ASM SMC. However, the trend was the reverse with the levels of inactive RhoA (GDP-RhoA-RhoGDI complex) and MYPT1. We conclude that RhoA/ROCK play a critical role in maintenance of spontaneous tone in the IAS SMC via inhibition of myosin light chain phosphatase.

Possible drug targets for celiac disease

Celiac disease (CD) is an intestinal disorder caused by an altered immune response against wheat gluten, a common dietary antigen, and related cereal proteins. Both CD4+ and CD8+ T cells have a role in inducing the intestinal damage, although recent studies have also pinpointed the involvement of the innate immune response in CD pathogenesis. So far, the only available treatment for CD is the strict avoidance of gluten in the diet, but the poor compliance and the associated complications demand alternative therapies. During the last decade, the knowledge of genetic, molecular and cellular mechanisms leading to CD pathogenesis made great progress. The improved understanding of gluten peptides activating either adaptive or innate immune response, of HLA restriction molecules, as well as of cytokines that mediate most of the inflammatory reactions, opens several new promising perspectives for therapeutic intervention. This review discusses both molecular and cellular strategies to treat CD, including the use of proteolytic enzymes active on gluten peptides, antibodies neutralising IL-15 and IFN-gamma, drugs targeting HLA, regulatory cytokines and T cells.

The pathology of malabsorption: current concepts

Intestinal malabsorption results from a wide variety of causes, which can most easily be organized into three groups. Maldigestion arises from problems with mixing or with digestive mediators, and includes post-gastrectomy patients and those with deficiencies of pancreatic or intestinal enzymes, or of bile salts. Mucosal and mural causes of malabsorption are abundant, and include gluten-sensitive enteropathy, tropical sprue, autoimmune enteropathy, and HIV/AIDS-related enteropathy, as well as mural conditions such as systemic sclerosis. Finally, microbial causes of malabsorption include bacterial overgrowth, Whipple's disease, and numerous infections or infestations that are most frequently seen in immunocompromised patients. An overview of the most common and interesting entities in each of these categories follows, along with a discussion of current concepts. Mucosal conditions and microbial causes of malabsorption are given special attention.

Fatal encephalitis in a patient with refractory celiac disease presenting with myorhythmia and carpal spasm

We report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed.

Spontaneously tonic smooth muscle has characteristically higher levels of RhoA/ROK compared with the phasic smooth muscle

The internal anal sphincter (IAS) tone is important for the rectoanal continence. The RhoA/Rho kinase (ROK) pathway has been associated with the agonist-induced sustained contraction of the smooth muscle, but its role in the spontaneously tonic smooth muscle is not known. Present studies compared expression of different components of the RhoA/ROK pathway between the IAS (a truly tonic SM), the rectal smooth muscle (RSM) (a mixture of phasic and tonic), and anococcygeus smooth muscle (ASM) (a purely phasic SM) of rat. RT-PCR and Western blot analyses were performed to determine RhoA, ROCK-II, CPI-17, MYPT1, and myosin light-chain 20 (MLC20). Phosphorylated CPI-17 at threonine-38 residue (p(Thr38)-CPI-17), MYPT1 at threonine-696 residue (p(Thr696)-MYPT1), and MLC20 at threonine-18/serine-19 residues (p(Thr18/Ser19)-MLC20) were also determined in the basal state and after pretreatment with the ROK inhibitor Y 27632. In addition, we compared the effect of Y 27632 on the basal isometric tension and ROK activity in the IAS vs. the RSM. Our data show the highest levels of RhoA, ROCK-II, CPI-17, MLC20, and of phospho-MYPT1, -CPI-17, and -MLC20 in the IAS followed by in the RSM and ASM. Conversely, MYPT1 levels were lowest in the IAS and highest in the ASM. In the IAS, Y 27632 caused a concentration-dependent decrease in the basal tone, levels of phospho-MYPT1, -CPI-17, and -MLC20, and ROK activity. We conclude that RhoA/ROK plays a critical role in the basal tone in the IAS by the inhibition of MLC phosphatase via the phosphorylation of MYPT1 and CPI-17.

Monitoring non-responsive patients with celiac disease

Current data clearly suggest that VCE has an important role in the diagnostic workup of complicated Cd, especially in those cases with suspected RCd or EATL. This is supported by the high yield of relevant pathological findings in distal parts of the small intestine, such as severe ulceration and mucosal infiltration, by VCE compared to conventional upper GI endoscopy. In this setting, VCE allows for an assessment of the extent of small bowel involvement, detection of overt though often small neoplasms and assists in planning further diagnostic procedures, especially push or double-balloon enteroscopy which are necessary to obtain specimens either to rule out or to confirm aberrant monoclonal T cell proliferation. Currently, those patients in whom RCd type II or EATL are excluded profit most from a thorough diagnostic workup, since most of them can be treated or cured pharmacologically. At present the prognosis of RCd type II or EATL is poor due to lack of effective therapies. However, treatments that effectively target the aberrant lymphocytes can be anticipated.

An approach to duodenal biopsies

The introduction of endoscopy of the upper digestive tract as a routine diagnostic procedure has increased the number of duodenal biopsy specimens. Consequently, the pathologist is often asked to evaluate them. In this review, a practical approach to the evaluation of a duodenal biopsy specimen is discussed. An overview of the handling of specimens is given and the normal histology and commonly encountered diseases are discussed. Finally, a description of commonly seen infections is provided, together with an algorithmic approach for diagnosis.

Factitious diarrhea masquerading as refractory celiac disease

A 23-year-old female with a history of a histologically confirmed diagnosis of celiac disease was referred to our institution for refractory celiac disease for consideration of immunosuppressive therapy. Full workup revealed an elevated fecal magnesium level, and a concurrent diagnosis of laxative abuse was confirmed after discussion with the family. This case highlights the importance of considering factitious diarrhea in all patients admitted for refractory diarrhea, even those with documented underlying conditions.