Fatigue as an Extra-Intestinal Manifestation of Celiac Disease: A Systematic Review.

Celiac disease may present with a range of different symptoms, including abdominal problems in a broader sense, iron deficiency and “constant tiredness”. All of these symptoms should consequently lead the clinicians to consider celiac disease as a potential etiopathogenetic cause. Although the pathophysiology of celiac disease is well documented, the actual mechanisms for disease presentation(s) are less well understood. We here address the topic of fatigue in celiac disease. A systematic literature search identified 298 papers of which five met the criteria for full evaluation. None of the reviewed papers were of high quality and had several methodological weaknesses. We conclude that there is an unmet need to study the contributing factors and management of fatigue in celiac disease.publishedVersio

Strong Clonal Relatedness between Serum and Gut IgA despite Different Plasma Cell Origins

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Rapid Accumulation of CD14+CD11c+ Dendritic Cells in Gut Mucosa of Celiac Disease after in vivo Gluten Challenge

Of antigen-presenting cells (APCs) expressing HLA-DQ molecules in the celiac disease (CD) lesion, CD11c(+) dendritic cells (DCs) co-expressing the monocyte marker CD14 are increased, whereas other DC subsets (CD1c(+) or CD103(+)) and CD163(+)CD11c(-) macrophages are all decreased. It is unclear whether these changes result from chronic inflammation or whether they represent early events in the gluten response. We have addressed this in a model of in vivo gluten challenge.Treated HLA-DQ2(+) CD patients (n = 12) and HLA-DQ2(+) gluten-sensitive control subjects (n = 12) on a gluten-free diet (GFD) were orally challenged with gluten for three days. Duodenal biopsies obtained before and after gluten challenge were subjected to immunohistochemistry. Single cell digests of duodenal biopsies from healthy controls (n = 4), treated CD (n = 3) and untreated CD (n = 3) patients were analyzed by flow cytometry.In treated CD patients, the gluten challenge increased the density of CD14(+)CD11c(+) DCs, whereas the density of CD103(+)CD11c(+) DCs and CD163(+)CD11c(-) macrophages decreased, and the density of CD1c(+)CD11c(+) DCs remained unchanged. Most CD14(+)CD11c(+) DCs co-expressed CCR2. The density of neutrophils also increased in the challenged mucosa, but in most patients no architectural changes or increase of CD3(+) intraepithelial lymphocytes (IELs) were found. In control tissue no significant changes were observed.Rapid accumulation of CD14(+)CD11c(+) DCs is specific to CD and precedes changes in mucosal architecture, indicating that this DC subset may be directly involved in the immunopathology of the disease. The expression of CCR2 and CD14 on the accumulating CD11c(+) DCs indicates that these cells are newly recruited monocytes

Linking Spatial Structure and Community-Level Biotic Interactions through Cooccurrence and Time Series Modeling of the Human Intestinal Microbiota

The gastrointestinal (GI) microbiome is a densely populated ecosystem where dynamics are determined by interactions between microbial community members, as well as host factors. The spatial organization of this system is thought to be important in human health, yet this aspect of our resident microbiome is still poorly understood. In this study, we report significant spatial structure of the GI microbiota, and we identify general categories of spatial patterning in the distribution of microbial taxa along a healthy human GI tract. We further estimate the biotic interaction structure in the GI microbiota, both through time series and cooccurrence modeling of microbial community data derived from a large number of sequentially collected fecal samples. Comparison of these two approaches showed that species pairs involved in significant negative interactions had strong positive contemporaneous correlations and vice versa, while for species pairs without significant interactions, contemporaneous correlations were distributed around zero. We observed similar patterns when comparing these models to the spatial correlations between taxa identified in the adherent microbiota. This suggests that colocalization of microbial taxon pairs, and thus the spatial organization of the GI microbiota, is driven, at least in part, by direct or indirect biotic interactions. Thus, our study can provide a basis for an ecological interpretation of the biogeography of the human gut

Non-coeliac gluten sensitivity

Irritable bowel syndrome‐like symptoms in response to wheat ingestion is common and well described, but whether the reaction is due to gluten (i.e., non‐coeliac gluten sensitivity), other wheat proteins, or FODMAPs (mostly fructans) alone or in combinations has not been clearly defined. Exclusion of coeliac disease in the presence of negative serology, and normal villous architecture but increased density of intraepithelial lymphocytes on duodenal biopsies, is difficult. Furthermore, the confidence by which a positive diagnosis is made or non‐coeliac gluten sensitivity is excluded by blinded placebo‐controlled rechallenge with wheat protein is reduced by strong nocebo responses generally found in patients with self‐reported non‐coeliac gluten sensitivity. The absence of a clear biological mechanism of action and difficulties with the design and interpretation of research studies have plunged this entity into even deeper controversy. In the absence of clarity in its diagnosis, the epidemiology, prognosis, and therapeutic approaches to a patient who may be gluten sensitive remain to be determined. Adequate understanding of the issues surrounding the controversy and further research will slowly unravel the truth behind the problem. This research has been published in Journal of Gastroenterology and Hepatology. © 2017 Wile

No major reduction in bone mineral density after long-term treatment of patients with Celiac Disease

Background At time of diagnosis, patients with celiac disease (CD) have been shown to have lower bone mineral density (BMD) than healthy controls. It is unclear whether adult patients with CD can regain a normal BMD after treatment with a gluten-free diet (GFD). Methods Patients diagnosed with CD as adults, who had been treated with GFD for a minimum of two years, were examined by dual energy X-ray absorptiometry (DXA) to determine BMD at femoral neck and spine L2-4. Adherence to GFD was measured using the Celiac Disease Adherence Test (CDAT) scoring tool. Results 143 CD patients underwent DXA assessment, mean age was 55.8 years and mean treatment duration was 9.3 years. 67% of the patients were women, and 51% of these were postmenopausal. The prevalence of low bone mass (Z-score ≤ −1.0) was 18.2% (95%CI: 12.7–25.3%) at femoral neck and 23.1% (95%CI: 16.9–30.6%) at spine L2-4. An increase in low bone density prevalence at spine L2-4 compared to the expected prevalence (p = 0.016) was limited to the postmenopausal women. In a multiple regression analysis, only postmenopausal status and poor adherence to GFD was independently associated with reduced bone density, this however limited to spine L2-4. Conclusion Our study shows a small increase in the prevalence of low bone density at lumbar spine limited to the postmenopausal women. The main finding is that the majority of the CD patients after two years of treatment with GFD had a normal bone density when adjusted for age, gender, ethnicity and weight

No major reduction in bone mineral density after long-term treatment of patients with Celiac Disease

Background At time of diagnosis, patients with celiac disease (CD) have been shown to have lower bone mineral density (BMD) than healthy controls. It is unclear whether adult patients with CD can regain a normal BMD after treatment with a gluten-free diet (GFD). Methods Patients diagnosed with CD as adults, who had been treated with GFD for a minimum of two years, were examined by dual energy X-ray absorptiometry (DXA) to determine BMD at femoral neck and spine L2-4. Adherence to GFD was measured using the Celiac Disease Adherence Test (CDAT) scoring tool. Results 143 CD patients underwent DXA assessment, mean age was 55.8 years and mean treatment duration was 9.3 years. 67% of the patients were women, and 51% of these were postmenopausal. The prevalence of low bone mass (Z-score ≤ −1.0) was 18.2% (95%CI: 12.7–25.3%) at femoral neck and 23.1% (95%CI: 16.9–30.6%) at spine L2-4. An increase in low bone density prevalence at spine L2-4 compared to the expected prevalence (p = 0.016) was limited to the postmenopausal women. In a multiple regression analysis, only postmenopausal status and poor adherence to GFD was independently associated with reduced bone density, this however limited to spine L2-4. Conclusion Our study shows a small increase in the prevalence of low bone density at lumbar spine limited to the postmenopausal women. The main finding is that the majority of the CD patients after two years of treatment with GFD had a normal bone density when adjusted for age, gender, ethnicity and weight

Machine Learning Analysis of Naïve B-Cell Receptor Repertoires Stratifies Celiac Disease Patients and Controls

Celiac disease (CeD) is a common autoimmune disorder caused by an abnormal immune response to dietary gluten proteins. The disease has high heritability. HLA is the major susceptibility factor, and the HLA effect is mediated via presentation of deamidated gluten peptides by disease-associated HLA-DQ variants to CD4+ T cells. In addition to gluten-specific CD4+ T cells the patients have antibodies to transglutaminase 2 (autoantigen) and deamidated gluten peptides. These disease-specific antibodies recognize defined epitopes and they display common usage of specific heavy and light chains across patients. Interactions between T cells and B cells are likely central in the pathogenesis, but how the repertoires of naïve T and B cells relate to the pathogenic effector cells is unexplored. To this end, we applied machine learning classification models to naïve B cell receptor (BCR) repertoires from CeD patients and healthy controls. Strikingly, we obtained a promising classification performance with an F1 score of 85%. Clusters of heavy and light chain sequences were inferred and used as features for the model, and signatures associated with the disease were then characterized. These signatures included amino acid (AA) 3-mers with distinct bio-physiochemical characteristics and enriched V and J genes. We found that CeD-associated clusters can be identified and that common motifs can be characterized from naïve BCR repertoires. The results may indicate a genetic influence by BCR encoding genes in CeD. Analysis of naïve BCRs as presented here may become an important part of assessing the risk of individuals to develop CeD. Our model demonstrates the potential of using BCR repertoires and in particular, naïve BCR repertoires, as disease susceptibility markers

On the immune response to barley in celiac disease: Biased and public T-cell receptor usage to a barley unique and immunodominant gluten epitope

Celiac disease (CeD) is driven by CD4+ T‐cell responses to dietary gluten proteins of wheat, barley, and rye when deamidated gluten epitopes are presented by certain disease‐associated HLA‐DQ allotypes. About 90% of the CeD patients express HLA‐DQ2.5. In such patients, five gluten epitopes dominate the anti‐gluten T‐cell response; two epitopes unique to wheat, two epitopes present in wheat, barley, and rye and one epitope unique to barley. Despite presence of barley in commonly consumed food and beverages and hence being a prominent source of gluten, knowledge about T‐cell responses elicited by barley in CeD is scarce. Therefore, in this study, we explored T‐cell response toward the barley unique epitope DQ2.5‐hor‐3 (PIPEQPQPY) by undertaking HLA‐DQ:gluten peptide tetramer staining, single‐cell T‐cell receptor (TCR) αβ sequencing, T‐cell cloning, and T‐cell proliferation studies. We demonstrate that majority of the CeD patients generate T‐cell response to DQ2.5‐hor‐3, and this response is characterized by clonal expansion, preferential TCR V‐gene usage and public TCR features thus echoing findings previously made for wheat gluten epitopes. The knowledge that biased and public TCRs underpin the T‐cell response to all the immunodominant gluten epitopes in CeD suggests that such T cells are promising diagnostic and therapeutic targets

HLA-DQ-Gluten Tetramer Blood Test Accurately Identifies Patients With and Without Celiac Disease in Absence of Gluten Consumption

Background & Aims: Celiac disease is characterized by HLA-DQ2/8-restricted responses of CD4+ T cells to cereal gluten proteins. A diagnosis of celiac disease based on serologic and histologic evidence requires patients to be on gluten-containing diets. The growing number of individuals adhering to a gluten-free diet (GFD) without exclusion of celiac disease complicates its detection. HLA-DQ–gluten tetramers can be used to detect gluten-specific T cells in blood of patients with celiac disease, even if they are on a GFD. We investigated whether an HLA-DQ–gluten tetramer-based assay accurately identifies patients with celiac disease. Methods: We produced HLA-DQ–gluten tetramers and added them to peripheral blood mononuclear cells isolated from 143 HLA-DQ2.5+ subjects (62 subjects with celiac disease on a GFD, 19 subjects without celiac disease on a GFD [due to self-reported gluten sensitivity], 10 subjects with celiac disease on a gluten-containing diet, and 52 presumed healthy individuals [controls]). T cells that bound HLA-DQ–gluten tetramers were quantified by flow cytometry. Laboratory tests and flow cytometry gating analyses were performed by researchers blinded to sample type, except for samples from subjects with celiac disease on a gluten-containing diet. Test precision analyses were performed using samples from 10 subjects. Results: For the HLA-DQ–gluten tetramer-based assay, we combined flow-cytometry variables in a multiple regression model that identified individuals with celiac disease on a GFD with an area under the receiver operating characteristic curve value of 0.96 (95% confidence interval [CI] 0.89–1.00) vs subjects without celiac disease on a GFD. The assay detected individuals with celiac disease on a gluten-containing diet vs controls with an area under the receiver operating characteristic curve value of 0.95 (95% CI 0.90–1.00). Optimized cutoff values identified subjects with celiac disease on a GFD with 97% sensitivity (95% CI 0.92–1.00) and 95% specificity (95% CI 0.84–1.00) vs subjects without celiac disease on a GFD. The values identified subjects with celiac disease on a gluten-containing diet with 100% sensitivity (95% CI 1.00–1.00]) and 90% specificity (95% CI 0.83–0.98) vs controls. In an analysis of 4 controls with positive results from the HLA-DQ–gluten tetramer test, 2 had unrecognized celiac disease and the remaining 2 had T cells that proliferated in response to gluten antigen in vitro. Conclusions: An HLA-DQ–gluten tetramer-based assays that detects gluten-reactive T cells identifies patients with and without celiac disease with a high level of accuracy, regardless of whether the individuals are on a GFD. This test would allow individuals with suspected celiac disease to avoid gluten challenge and duodenal biopsy, but requires validation in a larger study. Clinicaltrials.gov no: NCT02442219