Refractory Celiac Disease Patients Research Articles

Budesonide Induces Favourable Histologic and Symptomatic Recovery in Patients with Non-responsive and Refractory Coeliac Disease When Given in an Open Capsule Format

IntroductionNon-responsive coeliac disease (NRCD), where symptoms and enteropathy persist despite a prolonged gluten-free diet (GFD), is common. Refractory coeliac disease (RCD), characterised by malabsorption and extensive enteropathy, is rare but serious. In both, treatment options are limited. Topical budesonide may help and an open capsule format promoting proximal small intestinal delivery may be advantageous.AimTo describe the effect of budesonide and its presentation on mucosal healing, symptoms, and tolerability in NRCD and RCD.MethodsA retrospective cohort study of NRCD and RCD patients who received budesonide for enteropathy despite a strict GFD for over 12 months. Primary outcome was improvement in histology. Symptoms and adverse treatment effects were recorded.Results50 patients with NRCD (n = 14; 86% F), RCD type 1 (n = 30; 60% F), and RCD type 2 (n = 6 based on aberrant duodenal T cells; 33% F) were identified. Common RCD symptoms were diarrhoea (68%), fatigue (40%), and weight loss (34%). 16 received closed capsule budesonide (CCB) 9 mg OD and 35 open capsule budesonide (OCB) 3 mg 3 times a day. Complete and partial mucosal healing was significantly higher after OCB compared to CCB (p < 0.001, Mann–Whitney U test). Symptom improvement was also significantly higher after OCB compared to CCB (p = 0.002, Mann–Whitney U test). Side effects were mild and self-limiting and were reported in 25% of both cohorts.ConclusionOCB was well tolerated and associated with improvements in enteropathy (83%) and symptoms (90%) in NRCD and RCD. Our findings support OCB as the preferred 1st-line therapy for NRCD and RCD type 1.

The combination of clinical parameters and immunophenotyping of intraepithelial lymphocytes allows to assess disease severity in refractory celiac disease

BackgroundFlow cytometry of intestinal lymphocytes is discussed to be a stronger predictor of enteropathy-associated T-cell lymphoma development in refractory celiac disease than T-cell clonality analysis. AimsTo investigate possible associations between clinical characteristics of refractory celiac disease patients and aberrant intraepithelial lymphocytes and to evaluate the accuracy of immunophenotyping for the identification of high-risk refractory celiac disease. MethodsFlow cytometry of isolated lymphocytes from duodenal biopsies of controls and celiac disease patients was performed and results were compared to clinical data. ResultsFlow cytometry analysis was performed on 42 controls, 37 non-complicated celiac disease and 30 refractory celiac disease cases with or without T-cell receptor clonality. Elevated aberrant intraepithelial lymphocyte counts were significantly associated with severe malabsorption. A 15% cut-off (aberrant lymphocytes among all lymphocytes) had the best discriminatory ability to identify high-risk patients. However, this technique failed to identify some high-risk cases (sensitivity 63%, specificity 100%). The severity of malabsorption was added to the criteria for high-risk refractory celiac disease, improving the correct patients’ allocation (sensitivity 100%, specificity 96%). ConclusionImmunophenotyping of aberrant intraepithelial lymphocytes is a good predictor for high-risk refractory celiac disease. Furthermore, adding the evaluation of malabsorption to the diagnostic assessment of refractory celiac disease optimizes accuracy.

Frequency of Gluten-Reactive T Cells in Active Celiac Lesions Estimated by Direct Cell Cloning.

Chronic inflammation of the small intestine in celiac disease is driven by activation of CD4+ T cells that recognize gluten peptides presented by disease-associated HLA-DQ molecules. We have performed direct cell cloning of duodenal biopsies from five untreated and one refractory celiac disease patients, and three non-celiac disease control subjects in order to assess, in an unbiased fashion, the frequency of gluten-reactive T cells in the disease-affected tissue as well as the antigen fine specificity of the responding T cells. From the biopsies of active disease lesions of five patients, 19 T-cell clones were found to be gluten-reactive out of total 1,379 clones tested. This gave an average of 1.4% (range 0.7% - 1.9%) of gluten-reactive T cells in lamina propria of active celiac lesions. Interestingly, also the patient with refractory celiac disease had gluten-reactive T cell clones in the lamina propria (5/273; 1.8%). In comparison, we found no gluten-reactive T cells in any of the total 984 T-cell clones screened from biopsies from three disease control donors. Around two thirds of the gluten-reactive clones were reactive to a panel of peptides representing known gluten T-cell epitopes, of which two thirds were reactive to the immunodominant DQ2.5-glia-α1/DQ2.5-glia-α2 and DQ2.5-glia-ω1/DQ2.5-glia-ω2 epitopes. This study shows that gluten-reactive T cells in the inflamed duodenal tissue are prevalent in the active disease lesion, and that many of these T cells are reactive to T-cell epitopes that are not yet characterized. Knowledge of the prevalence and epitope specificity of gluten-specific T cells is a prerequisite for therapeutic efforts that target disease-specific T cells in celiac disease.

Verifying Diagnosis of Refractory Celiac Disease With Urine Gluten Immunogenic Peptides as Biomarker.

Refractory celiac disease (RCD) involves T-lymphocyte activation despite supposed absence of gluten exposure. Assessing dietary adherence is the cornerstone of RCD diagnosis, but available diagnostic tools fail to monitor gluten-free diet (GFD). A recently acknowledged GFD biomarker is gluten immunogenic peptides (GIP) in urine. This study assessed urine GIP to verify whether RCD patients could be reclassified as “exposed to gluten.” Three out of four RCD patients had at least two positive-GIP urine samples in a follow-up of 3 months, demonstrating gluten exposure. Urine GIP may enable the accurate RCD verification and decrease overuse of immunosuppressants, increasing cost effectiveness.

Faecal Scent as a Novel Non-Invasive Biomarker to Discriminate between Coeliac Disease and Refractory Coeliac Disease: A Proof of Principle Study.

Currently, the gold standard for diagnosis of coeliac disease (CD) is based on serology and gastroduodenoscopy with histology of duodenal mucosal biopsies. The aim of this study was to evaluate the potential of faecal volatile organic compounds (VOCs) analysis as a novel, non-invasive tool to discriminate between CD in remission in patients on a gluten-free diet (GFD), refractory coeliac disease (RCD) and controls without CD. Patients with an established diagnosis of CD on a GFD, RCD and healthy controls (HC) were instructed to collect a faecal sample. All subjects completed questionnaires on clinical symptoms, lifestyle and dietary information. Faecal VOCs were measured using gas chromatography-ion mobility spectrometry. A total of 13 CD, 7 RCD and 10 HC were included. A significant difference in VOC profiles between CD and RCD patients (area under the curve (AUC) ± 95% CI: 0.91 (0.79–1) p = 0.000) and between CD and HC (AUC ± 95% CI: 0.71 (0.51–0.91) p = 0.0254) was observed. We found no significant differences between faecal VOC patterns of HC and RCD. Based on faecal VOCs, CD could be discriminated from RCD and HC. This implies that faecal VOC analysis may hold potential as a novel non-invasive biomarker for RCD. Future studies should encompass a larger cohort to further investigate and validate this prior to application in clinical practice.

Open-Capsule Budesonide for Refractory Celiac Disease.

Refractory celiac disease (RCD) is a rare condition often associated with poor prognosis. Various immunosuppressive medications (IMs) have been used with modest success. We describe outcomes in patients treated with open-capsule budesonide (OB), including those for whom IM treatment failed. We identified RCD patients treated with OB at Mayo Clinic, Rochester, Minnesota from 2003 to 2015. Demographic, serologic, and clinical variables were analyzed. We identified 57 patients who received OB for suspected RCD. Based on clonal T-cell receptor gamma gene rearrangement or aberrant phenotype of intraepithelial lymphocytes (IELs), 13 patients (23%) were classified as having RCD-2 and 43 (75%) as RCD-1. In one patient (2%) TCR gene rearrangement status was unknown. Most patients were women (69%), mean (s.d.) age was 60.5 (3.5) years and body mass index was 28.4 (4.5) kg/m2. The majority had diarrhea (72%), with median of 6 bowel movements per day (range, 4-25). IM treatment (azathioprine, systemic corticosteroids, or regular budesonide) had failed in nearly half. Twenty-four patients (42%) had anemia and 12 (21%) had hypoalbuminemia. All had Marsh 3 lesions on biopsy: 3a (19%), 3b (46%), and 3c (35%). After OB therapy, the majority had clinical (92%) and histologic (89%) improvement. Follow-up biopsy in 7 out of 13 patients with RCD-2 (53%) showed an absence of clonal TCR gamma gene rearrangement/aberrant IEL phenotype previously seen. On follow-up, 2 patients (4%) died of enteropathy-associated T-cell lymphoma. Most patients with RCD show clinical and histopathologic improvement with OB therapy, including those with failure of IMs. OB is a promising therapeutic option for management of RCD.

Salivary Gluten Degradation and Oral Microbial Profiles in Healthy Individuals and Celiac Disease Patients.

Celiac disease (CD) is a chronic immune-mediated enteropathy induced by dietary gluten in genetically predisposed individuals. Saliva harbors the second highest bacterial load of the gastrointestinal (GI) tract after the colon. We hypothesized that enzymes produced by oral bacteria may be involved in gluten processing in the intestine and susceptibility to celiac disease. The aim of this study was to investigate salivary enzymatic activities and oral microbial profiles in healthy subjects versus patients with classical and refractory CD. Stimulated whole saliva was collected from patients with CD in remission (n = 21) and refractory CD (RCD; n = 8) and was compared to healthy controls (HC; n = 20) and subjects with functional GI complaints (n = 12). Salivary gluten-degrading activities were monitored with the tripeptide substrate Z-Tyr-Pro-Gln-pNA and the α-gliadin-derived immunogenic 33-mer peptide. The oral microbiome was profiled by 16S rRNA-based MiSeq analysis. Salivary glutenase activities were higher in CD patients compared to controls, both before and after normalization for protein concentration or bacterial load. The oral microbiomes of CD and RCD patients showed significant differences from that of healthy subjects, e.g., higher salivary levels of lactobacilli (P < 0.05), which may partly explain the observed higher gluten-degrading activities. While the pathophysiological link between the oral and gut microbiomes in CD needs further exploration, the presented data suggest that oral microbe-derived enzyme activities are elevated in subjects with CD, which may impact gluten processing and the presentation of immunogenic gluten epitopes to the immune system in the small intestine.IMPORTANCE Ingested gluten proteins are the triggers of intestinal inflammation in celiac disease (CD). Certain immunogenic gluten domains are resistant to intestinal proteases but can be hydrolyzed by oral microbial enzymes. Very little is known about the endogenous proteolytic processing of gluten proteins in the oral cavity. Given that this occurs prior to gluten reaching the small intestine, such enzymes are likely to contribute to the composition of the gluten digest that ultimately reaches the small intestine and causes CD. We demonstrated that endogenous salivary protease activities are incomplete, likely liberating peptides from larger gluten proteins. The potentially responsible microbes were identified. The study included refractory CD patients, who have been studied less with regard to CD pathogenesis.

Cross-sectional imaging in refractory celiac disease.

The purpose of this study is to identify unique imaging findings of refractory celiac disease (RCD) including Type I RCD, Type II RCD versus healed celiac disease (CD). A retrospective study of patients with known CD and refractory symptoms with cross-sectional imaging was performed. We included patients who underwent T cell receptor rearrangement or T-cell immunophenotyping studies on small bowel (SB) biopsies to classify patients into: healed CD, Type I RCD, or Type II RCD. GI radiologists performed a blinded review of the imaging studies. One-hundred eighteen patients (32 healed; 67 Type I RCD; 19 Type II RCD) were included (mean age 53±6years; 62% female). The presence of any fold pattern abnormality was more likely to be found in Type II and Type I RCD than healed CD (53% vs. 43% vs.16%; p=0.009). Type II RCD patients were more likely than Type I RCD and healed CD to have imaging findings of ulcerative jejunitis (26% vs. 6% vs. 3%; p=0.009), SB wall thickening (37% vs. 16% vs. 0%; p=0.002) and SB dilation (26% vs. 7% vs. 6%; p=0.04). Type II RCD demonstrated non-significant trends for decreased number of jejunal folds only, SB mass, mesenteric lymphadenopathy, localized peri-mural edema, and intramural duodenal edema. Fold pattern abnormalities, ulcerative jejunitis, SB wall thickening, and SB dilation are more likely to be identified in cross-sectional imaging of RCD than healed CD. SB dilatation and ulcerative jejunitis are more likely to be found in Type II than Type I RCD.

Causes and Outcomes of Non-responsive Celiac Disease

Introduction: Majority of patients with celiac disease (CD) show improvement of symptoms on a gluten free diet(GFD). However, a subset, that ranges from 7-30%, have nonresponsive celiac disease (NRCD), and continue to have manifestations suggestive of CD even after GFD for 6-12 months. In previous studies, the most common etiology of NRCD was inadvertent gluten intake. Others included irritable bowel syndrome (IBS), refractory celiac disease(RCD), microscopic colitis(MC), lactase deficiency, small-intestinal bacterial overgrowth (SIBO). With this study we aim to expand our knowledge of NRCD through long term follow up of a large cohort of patients with NRCD. Methods: This is a retrospective review and preliminary analyses of follow up of 50 out of 162 patients identified with NRCD from 2004 to 2016. The study population were identified using a pre-established BIDMC CD database. Results: The mean follow up time after NRCD diagnosis was 6 years. In the 18 patients without a secure diagnosis initially, 14(78%) were later diagnosed. In 32 patients with a suspected etiology previously, 10(31%) changed diagnosis. The mean age of NRCD diagnosis was 61.9 and 78% were female. 7 patients(14%) had RCD. 4 developed RCD (all type I) while 3 previous RCD patients (2 were type II) continued to remain refractory. 26% were lost to follow up and 1 patient (with type II RCD) died from AML. Status of patients lost to follow up will be ascertained as possible as a part of our final study. 66% responded to treatment directed to NRCD etiology. 42% had inadvertent ingestion of gluten, with NRCD of 18% attributed to this exposure. MC and IBS were each present in 20%. 16% had GERD/Peptic ulcer disease(PUD) or H. pylori gastritis. 12% had SIBO while 8% had gastroparesis. Lactose intolerance was present in 2 patients. Conclusion: In our preliminary analysis, many patients(42%) had inadvertent gluten ingestion, emphasizing the importance of follow up with an expert dietitian. The mean follow up period (6 years) suggests the need for continued assessment for etiology. Almost half the patients had an update in the etiology for NRCD (see table), and most patients that were previously of unknown etiology were later diagnosed. About two-third of those who followed up, responded to treatment. Gluten exposure, MC, IBS, GERD/PUD/H.pylori gastritis, SIBO and RCD were the most common etiologies for NRCD. NRCD is treatable in most patients and continued evaluation in those of unknown etiology will usually result in diagnosis.Table 1

Despite sequence homologies to gluten, salivary proline-rich proteins do not elicit immune responses central to the pathogenesis of celiac disease.

Celiac disease (CD) is an inflammatory disorder triggered by ingested gluten, causing immune-mediated damage to the small-intestinal mucosa. Gluten proteins are strikingly similar in amino acid composition and sequence to proline-rich proteins (PRPs) in human saliva. On the basis of this feature and their shared destination in the gastrointestinal tract, we hypothesized that salivary PRPs may modulate gluten-mediated immune responses in CD. Parotid salivary secretions were collected from CD patients, refractory CD patients, non-CD patients with functional gastrointestinal complaints, and healthy controls. Structural similarities of PRPs with gluten were probed with anti-gliadin antibodies. Immune responses to PRPs were investigated toward CD patient-derived peripheral blood mononuclear cells and in a humanized transgenic HLA-DQ2/DQ8 mouse model for CD. Anti-gliadin antibodies weakly cross-reacted with the abundant salivary amylase but not with PRPs. Likewise, the R5 antibody, recognizing potential antigenic gluten epitopes, showed negligible reactivity to salivary proteins from all groups. Inflammatory responses in peripheral blood mononuclear cells were provoked by gliadins whereas responses to PRPs were similar to control levels, and PRPs did not compete with gliadins in immune stimulation. In vivo, PRP peptides were well tolerated and nonimmunogenic in the transgenic HLA-DQ2/DQ8 mouse model. Collectively, although structurally similar to dietary gluten, salivary PRPs were nonimmunogenic in CD patients and in a transgenic HLA-DQ2/DQ8 mouse model for CD. It is possible that salivary PRPs play a role in tolerance induction to gluten early in life. Deciphering the structural basis for the lack of immunogenicity of salivary PRPs may further our understanding of the toxicity of gluten.

Serum regenerating islet-derived 3-alpha is a biomarker of mucosal enteropathies.

The clinical presentation of organic and functional intestinal disorders can overlap and clinicians often rely on invasive and time-consuming procedures to make a final diagnosis. Regenerating islet-derived 3-alpha (Reg3α) is detectable in the circulation of patients with intestinal graft-versus host disease and patients with inflammatory bowel disease (IBD). To determine whether serum Reg3α testing is useful for discriminating mucosal enteropathies from functional intestinal disorders. We prospectively included 47 patients with active coeliac disease (ACD), 13 patients with refractory coeliac disease (RCD), seven patients with common variable immunodeficiency (CVID), 72 patients with active Crohn's disease, 22 patients with active ulcerative colitis (UC) and 28 patients with irritable bowel syndrome (IBS)-related diarrhoea. Sera were also taken from 10 CD patients before and after 6-12months of a gluten-free diet (GFD) and from 14 patients with IBD before and after induction therapy with Infliximab (IFX). Sera of 119 healthy volunteers were used to determine the cut-off value. Reg3α levels were measured by a commercial ELISA kit. Levels of Reg3α exceeded the cut-off value of the assay in 43/47(91%) ACD patients, 13/13(100%) RCD patients, 7/7(100%) CVID patients, 65/72(90%) Crohn's disease patients, 17/22(77%) UC patients and one patient with IBS(4%). Reg3α levels distinguished mucosal enteropathies from IBS with a sensitivity of 90% and a specificity of 96%. Reg3α levels significantly decreased in CD patients following a GFD and in IBD patients after treatment with IFX. Reg3α is a serum biomarker of intestinal damage that, combined with clinical data, identifies patients who should undergo invasive tests for diagnosing enteropathies.

PTH-117 Thymic Stromal Lymphopoietin Is Primarily Reduced In Refractory Coeliac Disease Duodenal Mucosa

IntroductionThymic stromal lymphopoietin (TSLP), a cytokine released by enterocytes and gut dendritic cells, promotes the development of Foxp3+ regulatory T cells and at the same time inhibits the development of...

Refractory coeliac disease in a country with a high prevalence of clinically‐diagnosed coeliac disease

Refractory coeliac disease (RCD) is thought to be a rare disorder, but the accurate prevalence is unknown. We aimed to identify the prevalence of and the risk factors for developing RCD in a Finnish population where the clinical detection rate of coeliac disease is high. The study involved 11 hospital districts in Finland where the number of treated RCD patients (n = 44), clinically diagnosed coeliac disease patients (n = 12 243) and adult inhabitants (n = 1.7 million) was known. Clinical characteristics at diagnosis of coeliac disease between the RCD patients and patients with uncomplicated disease were compared. The prevalence of RCD was 0.31% among diagnosed coeliac disease patients and 0.002% in the general population. Of the enrolled 44 RCD patients, 68% had type I and 23% type II; in 9% the type was undetermined. Comparing 886 patients with uncomplicated coeliac disease with these 44 patients that developed RCD later in life, the latter were significantly older (median 56 vs 44 years, P < 0.001), more often males (41% vs. 24%, P = 0.012) and seronegative (30% vs. 5%, P < 0.001) at the diagnosis of coeliac disease. Patients with evolving RCD had more severe symptoms at the diagnosis of coeliac disease, including weight loss in 36% (vs. 16%, P = 0.001) and diarrhoea in 54% (vs. 38%, P = 0.050). Refractory coeliac disease is very rare in the general population. Patients of male gender, older age, severe symptoms or seronegativity at the diagnosis of coeliac disease are at risk of future refractory coeliac disease and should be followed up carefully.

Dendritic cells promote expansion and survival of aberrant TCR-negative intraepithelial lymphocyte lines from refractory celiac disease type II patients

Celiac disease (CD) patients who fail to respond to a gluten-free diet suffer from refractory celiac disease (RCD). A marked expansion of intraepithelial lymphocytes (IEL) lacking surface TCR/CD3 expression characterizes the RCD subtype II. In up to 50% of RCDII patients these so-called aberrant IEL (a-IEL) develop into lymphoma and can disseminate into other tissues. Elevated levels of Interleukin-15 (IL-15) in the intestine of CD and RCD patients likely contribute to the expansion of a-IEL. Here, we investigated if interactions with other cells might also influence a-IEL expansion. Similar to IL-15, cells from the monocyte lineage, particularly mature dendritic cells (DCs), promoted proliferation, prevented apoptosis and induced IFNγ secretion of a-IEL derived from RCDII biopsies (RCDII cell lines), which in turn induced CXCL10. In contrast to IL-15, mature DCs did not induce proliferation of regular TCR+IEL lines, generated from CD biopsies and IL-15-blocking antibodies did not inhibit DC-induced proliferation of RCDII cell lines. Furthermore, proliferation was dependent on cell–cell contact, but independent of the HLA-genotype of the stimulating cells. Our results suggest that contact with DC, either in the epithelium or upon dissemination, contributes to uncontrolled expansion of a-IEL in RCDII, independent of HLA-genotype and IL-15.

Immunohistochemical and T-Cell Receptor Gene Rearrangement Analyses as Predictors of Morbidity and Mortality in Refractory Celiac Disease

Classification of refractory celiac disease (RCD) is based on the presence or absence of monoclonal expansions of intraepithelial lymphocytes (IELs) with an aberrant immunophenotype. To investigate the contribution of IEL parameters toward mortality and morbidity in RCD. IEL phenotype by immunohistochemistry and T-cell receptor (TCR) gene rearrangement by polymerase chain reaction were assessed in 73 RCD patients (type I=67, type II=6). Detection of a monoclonal TCR gene rearrangement and presence of <50% CD3 CD8 IELs were considered abnormal. Time to worsening of clinical symptoms and predictors of worsening were calculated by Kaplan-Meier and Cox proportional hazard analyses. Fewer than 50% CD3 CD8 IELs were detected in 30 patients and monoclonal TCR rearrangements in 6. Three patients died and 40 suffered clinical worsening despite treatment. Estimated 5-year survival rates decreased from 100% in patients with >50% CD3 CD8 IELs and polyclonal TCR to 88% and 50% in patients with <50% CD3 CD8 IELs and monoclonal TCR, respectively. Clinical worsening was more frequent (100%) among patients harboring a monoclonal TCR gene rearrangement with <50% CD3 CD8 IELs. These patients also showed shorter median time to clinical worsening (11 mo) when compared to patients with <50% CD3 CD8 IELs alone (21 mo), polyclonal TCR (38 mo), or >50% CD3 CD8 IELs alone (66 mo). After adjusting for age and gender, only the presence of <50% CD3 CD8 IELs was associated with increased risk for clinical worsening despite negative celiac serologies (hazard ratio=4.879; 95% confidence interval, 1.785-13.336; P=0.002). Presence of <50% CD3 CD8 IELs is a risk factor for clinical worsening in RCD and combined with a monoclonal TCR gene rearrangement result is associated with increased mortality. IEL phenotype and TCR gene rearrangement analyses provide differential information regarding morbidity and mortality in RCD.

Changes in Natural Foxp3+Treg but Not Mucosally-Imprinted CD62LnegCD38+Foxp3+Treg in the Circulation of Celiac Disease Patients

BackgroundCeliac disease (CD) is an intestinal inflammation driven by gluten-reactive CD4+ T cells. Due to lack of selective markers it has not been determined whether defects in inducible regulatory T cell (Treg) differentiation are associated with CD. This is of importance as changes in numbers of induced Treg could be indicative of defects in mucosal tolerance development in CD. Recently, we have shown that, after encounter of retinoic acid during differentiation, circulating gut-imprinted T cells express CD62LnegCD38+. Using this new phenotype, we now determined whether alterations occur in the frequency of natural CD62L+Foxp3+ Treg or mucosally-imprinted CD62LnegCD38+Foxp3+ Treg in peripheral blood of CD patients. In particular, we compared pediatric CD, aiming to select for disease at onset, with adult CD.MethodsCell surface markers, intracellular Foxp3 and Helios were determined by flow cytometry. Foxp3 expression was also detected by immunohistochemistry in duodenal tissue of CD patients.ResultsIn children, the percentages of peripheral blood CD4+Foxp3+ Treg were comparable between CD patients and healthy age-matched controls. Differentiation between natural and mucosally-imprinted Treg on the basis of CD62L and CD38 did not uncover differences in Foxp3. In adult patients on gluten-free diet and in refractory CD increased percentages of circulating natural CD62L+Foxp3+ Treg, but normal mucosally-imprinted CD62LnegCD38+Foxp3+ Treg frequencies were observed.ConclusionsOur data exclude that significant numeric deficiency of mucosally-imprinted or natural Foxp3+ Treg explains exuberant effector responses in CD. Changes in natural Foxp3+ Treg occur in a subset of adult patients on a gluten-free diet and in refractory CD patients.

Differential IL-13 Production by Small Intestinal Leukocytes in Active Coeliac Disease versus Refractory Coeliac Disease

A small fraction of coeliac disease (CD) patients have persistent villous atrophy despite strict adherence to a gluten-free diet. Some of these refractory CD (RCD) patients develop a clonal expansion of lymphocytes with an aberrant phenotype, referred to as RCD type II (RCDII). Pathogenesis of active CD (ACD) has been shown to be related to gluten-specific immunity whereas the disease is no longer gluten driven in RCD. We therefore hypothesized that the immune response is differentially regulated by cytokines in ACD versus RCDII and investigated mucosal cytokine release after polyclonal stimulation of isolated mucosal lymphocytes. Secretion of the TH2 cytokine IL-13 was significantly higher in lamina propria leukocytes (LPLs) isolated from RCDII patients as compared to LPL from ACD patients (P = 0.05). In patients successfully treated with a gluten-free diet LPL-derived IL-13 production was also higher as compared to ACD patients (P = 0.02). IL-13 secretion correlated with other TH2 as well as TH1 cytokines but not with IL-10 secretion. Overall, the cytokine production pattern of LPL in RCDII showed more similarities with LPL isolated from GFD patients than from ACD patients. Our data suggest that different immunological processes are involved in RCDII and ACD with a potential role for IL-13.

A New Model to Predict Survival in Patients with Refractory Celiac Disease (MRCD): Results from a Multinational Study

Purpose: Refractory celiac disease (RCD) is a severe complication of celiac disease. The aim of the study was to develop a new model to estimate survival of patients with RCD (MRCD). Methods: From a multinational registry of RCD patients, seven pre-selected variables were evaluated as predictors of 5-year mortality using Cox proportional hazards regression on the pooled set of subjects. To internally validate the individual factors and overall model performance, we used bootstrap re-sampling. With each bootstrap sample, the full multivariable model was estimated (training model) and then applied to the original sample to assess performance (testing model). To correct for bias in the original model fitting, we estimated the optimism in model accuracy as the average difference between training and test model c-statistic values. Regression coefficients from the final multivariable model were used to derive a risk score for 5-year mortality. Results: The multinational cohort was composed of 233 subjects across 7 centers (5 countries), with 150 (64%) women and a median age of 53 years (range, 15-88 years). One subject was excluded from the risk factor analyses due to lack of follow-up. Despite significant differences in several factors across the 7 centers, the rates of 5-year mortality did not differ significantly (p=0.41). The risk of 5-year mortality from the original multivariable model is summarized in Table 1 (apparent and bias-corrected model c-statistic was 0.756 and 0.725, respectively). The risk score point system (score range 0-14) is summarized in Table 2. Kaplan-Meier rates of survival are plotted by risk score quartiles in Figure (5-year survival 100% for score 0-4, 68-77% for score 5-9, and 38% for score 10-14).Table 1: Summary of variables and size of risk (Multivariable Model)Table 2: Risk score point systemFigure: [1469] Figure. Kaplan-Meier survival curves by risk score quartiles.Conclusion: The new MRCD score may be useful to estimate 5-year mortality risk in patients with RCD and may help guide therapeutic interventions in this most serious complication of celiac disease.

TCRβ Clonality Improves Diagnostic Yield of TCRγ Clonality in Refractory Celiac Disease

Refractory celiac disease (RCD) is a preneoplastic condition as many patients develop an enteropathy-type T-cell lymphoma, a mature T-cell receptor α-β lymphoma arising in the gut with an ominous outcome. Recently, research focused on a population of intraepithelial intestinal lymphocytes expressing the same lymphoma T-cell receptor variable region (V)γ, as shown by polymerase chain reaction (PCR) analysis and sequencing. Meanwhile, the Biomedicine and Health-2 Concerted Action has made available standardized, highly specific, and sensitive PCR assays not only for Vγ but also for Vβ. We verified whether analyzing both rearrangements in duodenal biopsies from RCD patients increases the diagnostic accuracy of this method. Duodenal biopsies were analyzed from 15 RCD patients, 21 negative controls, and 2 positive controls (enteropathy-type T-cell lymphoma complicating celiac disease). Multiplex clonality analyses were performed according to the Biomedicine and Health-2 protocols. PCR products were cloned and sequenced. Monoclonal rearrangements were found in 5/15 samples from patients with RCD (both rearrangements in 2 cases, Vβ only in 2, and only 1 solitary Vγ clonality). Monoclonality was found in 4/8 of the RCD patients who subsequently died, whereas only 1/7 of the patients still alive presented a monoclonal rearrangement. Positive controls revealed both monoclonal rearrangements; rearrangements were not detected in 20 of 21 negative controls. Sequencing of the amplified fragments confirmed the results. The combined analysis of both rearrangements allowed recognition of monoclonal populations in otherwise negative patients, with detection rates from 20% (Vγ only) to 33% (Vγ and Vβ), thus raising the likelihood of early identification of RCD patients at high risk of death.

The immunopathogenesis of celiac disease reveals possible therapies beyond the gluten-free diet

Celiac disease is a T cell-mediated autoimmune inflammatory disease of the small intestine that is activated by gluten. The diagnosis of celiac disease is challenging as patients display a wide range of symptoms and some are asymptomatic. A lifelong gluten-free diet is the only currently approved treatment of celiac disease. Although the diet is safe and effective, the compliance rates and patient acceptance vary. Furthermore, many patients treated with a gluten-free diet continue to be mildly to severely symptomatic with persistent histological abnormalities, and a small number of patients develop refractory celiac disease. New therapeutic adjuncts and potential alternatives to the gluten-free diet could improve the treatment options for these patients. Advances in understanding the immunopathogenesis of celiac disease have suggested several types of therapeutic strategies that may augment or supplant the gluten-free diet. Some of these strategies attempt to decrease the immunogenicity of gluten-containing grains by manipulating the grain itself or by using oral enzymes to break down immunogenic peptides that normally remain intact during digestion. Other strategies focus on preventing the absorption of these peptides, preventing tissue transglutaminase from rendering gluten peptides more immunogenic, or inhibiting their binding to celiac disease-specific antigen-presenting molecules. Strategies that limit T cell migration to the small intestine or that reestablish mucosal homeostasis and tolerance to gluten antigens are also being explored. Additionally, it is vital to develop new therapeutic options for refractory celiac disease patients. This review highlights therapeutic strategies that may ultimately improve the health and well-being of individuals with celiac disease.