Untreated Coeliac Disease Research Articles

Drug-induced Collagenous Sprue: A Reversible Small Bowel Mucosal Disorder

Collagenous sprue is an unusual small intestinal mucosal disorder characterized by flattened small intestinal mucosa, unusual sub-epithelial collagen deposits, increased intra-epithelial lymphocytes, often denuded epithelial cells and resistance to therapy, including a gluten-free diet. The disorder is heterogeneous with several potential causes now identified. Similar to sprue-like intestinal disease, collagenous sprue may be caused or precipitated by different pharmaceutical agents. Olmesartan, an angiotensin II inhibitor, often employed in treatment of hypertension, may cause a drug-induced form of sprue-like small intestinal disease with the pathological features of untreated celiac disease refractory to gluten-free diet treatment. In addition, collagenous sprue may be precipitated by olmesartan. Recognition and cessation of the medication has led to resolution of the small intestinal mucosal disorder without steroids or other treatment.

Relationship between duodenal microbiota composition, clinical features at diagnosis, and persistent symptoms in adult Coeliac disease

BackgroundDuodenal dysbiosis has been suggested to possibly influence the clinical manifestations of coeliac disease (CD), both at onset and when symptoms persist despite a gluten-free diet (GFD). AIMSTo evaluate the relationship between duodenal microbiota composition and: i) clinical phenotype of untreated CD (UCD); ii) presence and type of persistent symptoms despite a satisfactory serological and histological response to a strict GFD. MethodsDuodenal microbiota was analyzed by 16S rRNA sequencing and compared with i) clinical features in 12 adult UCD patients; ii) presence/absence and type of persistent symptoms (diarrhea-predominant vs. non-diarrhea predominant) in 25 adult treated coeliac patients (TCD) on a strict GFD. ResultsUCD with iron deficiency anemia (IDA) had a pro-inflammatory shift in their duodenal microbiota (reduction of Firmicutes, p = 0.03; increase of beta-Proteobacteria, p = 0.02) than those without IDA. TCD with persistent diarrhea showed a reduction of Actinobacteria (p = 0.03) and Rothia spp (p = 0.046) compared to TCD suffering from other type of persistent symptoms. ConclusionA distinctive duodenal microbiota profile is associated with IDA in UCD, and diarrhea-predominant persistent symptoms in TCD. Clinical interventions may include reconsidering patients presenting with IDA as a specific disease subtype, and dietary rebalancing if diarrhea persists despite histological response to a GFD.

Epitope mapping of anti-amelogenin IgG in untreated celiac children.

Children with untreated celiac disease (CeD) may develop enamel defects, and children with severe CeD have significantly increased levels of IgG to amelogenin, which may interfere with normal amelogenesis depending on which epitope(s) they bind. Children with untreated CeD (n=42), for whom CeD had been confirmed either by biopsy (n=17, cohort 1) or by the presence of particularly high serum levels of anti-transglutaminase 2 (TG2) IgA (n=25, cohort 2), were selected from 146 children with CeD, and 10 controls were selected from 34 children who did not have CeD. Samples from these 52 children were used for detailed IgG anti-amelogenin, X isoform (AMELX) epitope mapping using 31 overlapping, 10-22mer peptides in ELISA. Although sera from both groups showed reactivity to peptides containing sequences from the N and C terminus of AMELX, sera from children with CeD reacted more strongly to peptides from the central region (amino acids 75-150) containing both a binding site for transforming growth factor-β (TGF-β), as well as the enzymatic cleavage sites for matrix metalloproteinase-20 and for kallikrein-4. Antigen-specific extraction revealed that only IgG to the central region cross-reacted to gliadin. Thus, cross-reactive anti-gliadin/amelogenin IgG may affect normal amelogenesis by interfering with enzymatic degradation, proper folding, and/or TGF-β signaling in children with untreated CeD.

Automated interpretation of biopsy images for the detection of celiac disease using a machine learning approach

Background and objectivesCeliac disease is an autoimmune disease occurring in about 1 in 100 people worldwide. Early diagnosis and efficient treatment are crucial in mitigating the complications that are associated with untreated celiac disease, such as intestinal lymphoma and malignancy, and the subsequent high morbidity. The current diagnostic methods using small intestinal biopsy histopathology, endoscopy, and video capsule endoscopy (VCE) involve manual interpretation of photomicrographs or images, which can be time-consuming and difficult, with inter-observer variability. In this paper, a machine learning technique was developed for the automation of biopsy image analysis to detect and classify villous atrophy based on modified Marsh scores. This is one of the first studies to employ conventional machine learning to automate the use of biopsy images for celiac disease detection and classification. MethodsThe Steerable Pyramid Transform (SPT) method was used to obtain sub bands from which various types of entropy and nonlinear features were computed. All extracted features were automatically classified into two-class and multi-class, using six classifiers. ResultsAn accuracy of 88.89%, was achieved for the classification of two-class villous abnormalities based on analysis of Hematoxylin and Eosin (H&E) stained biopsy images. Similarly, an accuracy of 82.92% was achieved for the two-class classification of red-green-blue (RGB) biopsy images. Also, an accuracy of 72% was achieved in the classification of multi-class biopsy images. ConclusionThe results obtained are promising, and demonstrate the possibility of automating biopsy image interpretation using machine learning. This can assist pathologists in accelerating the diagnostic process without bias, resulting in greater accuracy, and ultimately, earlier access to treatment.

Reproductive Characteristics and Pregnancy Outcomes in Hidden Celiac Disease Autoimmunity.

Untreated symptomatic celiac disease (CD) adversely affects female reproduction; however, the effect of hidden CD autoimmunity is uncertain. We identified women who were not previously diagnosed with CD and tested positive for tissue transglutaminase and endomysial antibodies between 2006 and 2011 in a community-based retrospective cohort study. We evaluated (i) the rate of adverse pregnancy outcomes and medical complications of pregnancy in successful singleton deliveries and (ii) reproductive characteristics in seropositive women without a clinical diagnosis of CD and age-matched seronegative women. Among 17,888 women whose serum samples were tested for CD autoimmunity, 215 seropositive and 415 seronegative women were included. We reviewed 231 and 509 live singleton deliveries of 117 seropositive and 250 seronegative mothers, respectively. Menarche and menopausal age, gravidity, parity, and age at first child were similar in seropositive and seronegative women. CD seropositivity was not associated with an increased risk of maternal pregnancy complications. Maternal seropositivity was associated with small for gestational age in boys (OR 3.77, 95% CI: 1.47-9.71; P = 0.006), but not in girls (OR 0.57, 95% CI: 0.15-2.17; P = 0.41). CD serum positivity was not associated with prematurity, small for gestational age (birth weight <10th percentile), or 5-minute Apgar score of less than 7. Although underpowered, the present study did not show any difference in reproductive characteristics or rates of adverse pregnancy outcomes in women with and without CD autoimmunity, except for birth weight in male offspring. Larger studies are needed to determine the effects of CD autoimmunity on female reproduction.

Anaemia in Dermatitis Herpetiformis: Prevalence and Associated Factors at Diagnosis and One-year Follow-up.

Dermatitis herpetiformis is a cutaneous manifestation of coeliac disease. Anaemia is a common finding in patients with untreated coeliac disease, but little is known about the occurrence of anaemia in those with dermatitis herpetiformis. This study investigated the prevalence of anaemia and factors associated with anaemia in 250 patients with dermatitis herpetiformis, at diagnosis and one year after diagnosis. As controls, 139 patients with coeliac disease were included. Patient records were reviewed to gather baseline clinical, histological, and laboratory data. Follow-up data for patients with dermatitis herpetiformis were collected from patient records and via questionnaires or at followup visits. The prevalence of anaemia was 12% in patients with dermatitis herpetiformis and 17% in patients with coeliac disease at diagnosis (p = 0.257). Anaemia in patients with dermatitis herpetiformis was not associated with the severity of skin symptoms or small bowel damage. The prevalence of anaemia at a 1-year follow-up had increased to 19%, but it was associated mainly with dapsone treatment.

The Circulating Midkine in the Newly Diagnosed Celiac Disease: Clinical Implications.

Background:Celiac disease (CeD) is a chronic inflammatory small intestine disorder caused by an abnormal immune response to an array of the epitopes of the wheat gluten and related proteins of rye and barley in genetically susceptible individuals. Midkine (MK) is an angiogenic cytokine, chemotactic in the direction of polymorphonuclear neutrophils and macrophages, and a T-regulatory cell suppressor. So far, a possible relationship with CeD has not yet been explored. Diagnosis of CeD is based on serologic test in a clinical setting suggestive of CeD and confirmatory histologic examination of the duodenal biopsy. Sometimes, genetic testing of human leukocyte antigen (HLA)-DQ2 and HLA-DQ8 may be needed. The objective of this study was to measure and compare the circulating MK in the celiac patients and healthy individuals.Materials and Methods:Twenty newly untreated CeD cases and 20 normal controls were enrolled in this study. The enzyme-linked immunosorbent assay was used to measure the circulating MK in the celiac patients and controls.Results:There was insignificant difference in the circulating MK between the patients and controls (P > 0.05).Conclusions:The study results suggest that the MK marker does not have any diagnostic value in CeD activity to be used at the time of diagnosis or during follow-ups.

Circulating Pv-1 As A Marker of Celiac Disease-Associated Liver Injury

Aim: To investigate the role of endothelial PV-1 in patients with untreated celiac disease (CD)-associated liver injury. Materials & methods: PV-1 and PV-1 mRNA were measured in intestinal biopsies from untreated CD patients with elevated or normal alanine transaminaselevels, controls, patients with inflammatory bowel diseaseand patients with toxic liver injury. Circulating PV-1 levels were also evaluated. Results: Circulating PV-1 levels were significantly increased in the serum of patients with CD-associated liver injury and reverted to normal following a gluten-free diet. Mucosal PV-1 and PV-1 mRNA were no different in patients with CD-associated liver injury. Conclusion: Serum but not mucosal PV-1 represents a marker of gluten-dependent liver injury and response to a gluten-free diet in patients with untreated CD.

Celiac Disease in Kosovar Albanian Children: Evaluation of Clinical Features and Diagnosis.

Celiac disease is an immune-mediated disorder characterized by variable clinical manifestations, specific antibodies, HLA-DQ2/DQ8 haplotypes, and enteropathy. The aim of this study was to present the clinical spectrum and patterns of celiac disease in Kosovar Albanian children. A cross-sectional retrospective study was performed with Albanian children aged 0-18 years, treated for celiac disease in the Pediatric Clinic, University Clinical Center of Kosovo from 2005 to 2016. During the study period, 63 children were treated for celiac disease. The mean age at diagnosis was 5.5 years (SD ± 3.31). The mean age at celiac disease onset was 3.3 years (SD ± 2.02), while the mean delay from the first symptoms indicative of celiac disease to diagnosis was 2.2 years (SD ± 2.09). More than 70% of the patients were diagnosed in the first 7 years of life, mainly presented with gastrointestinal symptoms, while primary school children and adolescents mostly showed atypical symptoms (p<0.001). The classical form of celiac disease occurred in 78% of the cases. Sixty (95%) patients carried HLA-DQ2.5, DQ2.2 and/or HLA-DQ8 heterodimers, and only three of them tested negative. Kosovo, as the majority of developing countries, is still facing the classical form of celiac disease as the dominant mode of presentation; as a result, most children with other forms of the celiac disease remain undiagnosed. Physicians should be aware of the wide range of clinical presentations and utilize low testing thresholds in order to prevent potential long-term problems associated with untreated celiac disease.

Longevity, clonal relationship, and transcriptional program of celiac disease-specific plasma cells.

Disease-specific plasma cells (PCs) reactive with transglutaminase 2 (TG2) or deamidated gluten peptides (DGPs) are abundant in celiac disease (CeD) gut lesions. Their contribution toward CeD pathogenesis is unclear. We assessed expression of markers associated with PC longevity in 15 untreated and 26 treated CeD patients in addition to 13 non-CeD controls and performed RNA sequencing with clonal inference and transcriptomic analysis of 3,251 single PCs. We observed antigen-dependent V-gene selection and stereotypic antibodies. Generation of recombinant DGP-specific antibodies revealed a key role of a heavy chain residue that displays polymorphism, suggesting that immunoglobulin gene polymorphisms may influence CeD-specific antibody responses. We identified transcriptional differences between CeD-specific and non-disease-specific PCs and between short-lived and long-lived PCs. The short-lived CD19+CD45+ phenotype dominated in untreated and short-term-treated CeD, in particular among disease-specific PCs but also in the general PC population. Thus, the disease lesion of untreated CeD is characterized by massive accumulation of short-lived PCs that are not only directed against disease-specific antigens.

Long-term Consequences of Undiagnosed Celiac Seropositivity.

Diagnosed celiac disease (CD) is associated with lymphoproliferative malignancy and gastrointestinal cancer, but little is known about the long-term consequences of undiagnosed CD. We aimed to investigate long-term consequences of undiagnosed CD for mortality and incidence of cancer and other chronic diseases. We screened biobank serum samples for immunoglobulin (Ig) A and IgG tissue transglutaminase (TTG) and IgG deamidated gliadin peptide in a study of 8 population-based cohort studies comprising 16,776 participants examined during 1976-2012 and followed with >99% complete follow-up in Danish nationwide registries until December 31, 2017, regarding vital status and incidence of diseases. Undiagnosed CD was defined as antibody positivity (IgA-TTG or IgG-TTG ≥ 7 U/mL and/or IgG deamidated gliadin peptide ≥ 10 U/mL) in individuals without a diagnosis of CD recorded in the National Patient Register. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated by Cox regression analyses with age as the underlying time scale. The prevalence of undiagnosed CD was 1.0% with no statistically significant increase over time. Undiagnosed CD was associated with increased risk of cancer overall (HR, 1.57; 95% CI, 1.16-2.11), gastrointestinal cancer (HR, 2.33; 95% CI, 1.35-4.04), cancer of the uterus (HR, 3.95; 95% CI, 1.46-10.69), breast cancer (HR, 1.98; 95% CI, 1.02-3.82), head and neck cancer (HR, 3.12; 95% CI, 1.15-8.43), and cardiovascular disease (HR, 1.37; 95% CI, 1.01-1.85). We found no statistically significant association between undiagnosed CD and mortality (HR, 1.19; 95% CI, 0.87-1.61). Undiagnosed CD was associated with increased risk of cardiovascular disease and cancer suggesting that untreated CD has serious long-term health consequences not only affecting the gastrointestinal tract (see Visual Abstract, Supplementary Digital Content, http://links.lww.com/AJG/B566).

Hyperparathyroidism in celiac disease: A case study from UAE

Celiac disease affects 1% of the world population; however it is under diagnosed in UAE. The disease has many clinical manifestations, ranging from severe malabsorption to minimally symptomatic or non-symptomatic presentation. Hypocalcaemia is a common finding in celiac disease and could be the only presentation of the disease; however hypercalcemia has been previously reported in patients with celiac disease either due to primary hyperparathyroidism or tertiary hyperparathyroidism due to prolonged hypocalcaemia. A normal calcium level on the other hand in patients with untreated celiac disease who also have primary hyperparathyroidism can be due to interplay of these two conditions and may delay the diagnosis of primary Hyperparathyroidism. We report the very first case from our practice in UAE with untreated celiac disease and normal calcium level at presentation, where a diagnosis of primary hyperparathyroidism was not entertained initially. Patient went on gluten free diet which then caused normalization of intestinal abnormalities and likely calcium absorption manifesting as hypercalcemia on subsequent labs. This led to further work up and finally the diagnosis of Primary hyperparathyroidism due to parathyroid adenoma.

25-Hydroxyvitamin D, 1,25-Dihydroxyvitamin D, and Peripheral Bone Densitometry in Adults with Celiac Disease.

Background: Adults with celiac disease (CeD) show low bone mineral density (BMD) and high fracture risk. CeD guidelines suggest measurements of serum minerals and vitamin D. However, studies on vitamin levels in CeD patients are contradictory. Aim: To investigate in CeD, 25-hydroxy-vitamin D [25(OH)D], 1,25-dihydroxy-vitamin D [1,25(OH)2D], and related analytes and to evaluate their relationships to peripheral BMD as assessed by peripheral quantitative computed tomography (pQCT). Methods: Gluten-free diet (GFD)-treated, and untreated adult CeD patients naïve to vitamin D and calcium supplementation underwent measurements of serum 25(OH)D, 1,25(OH)2D, parathyroid hormone (PTH), total calcium, phosphate, and of radius BMD by pQCT. Results: Complete data were collected in 105 patients for lab tests and 87 patients for BMD. For lab tests, untreated CeD differed from treated CeD for 22.0% lower serum 25(OH)D (p = 0.023), 42.5% higher serum PTH (p < 0.001), and 13.0% higher serum 1,25(OH)2D (p = 0.029) in the presence of similar serum calcium and phosphorus (p > 0.35). For BMD, untreated CeD differed from treated CeD for lower diaphyseal cortical BMD (1133 and 1157 mg/cm3, p = 0.004) but not for distal BMD (total, trabecular, and subcortical, p > 0.13). Independent correlates of diaphyseal cortical BMD were GFD treatment and body mass index (p < 0.05). Conclusions: Data indicated that, compared to CeD patients on a gluten-free diet, untreated adult CeD patients at diagnosis had lower 25(OH)D, higher PTH, and higher 1,25(OH)2D in the absence of difference in serum calcium and phosphorus. 25(OH)D and 1,25(OH)2D, even below the normal range, were not associated with BMD. Our findings do not support the use of vitamin D supplementation for all CeD adults.

Narrative Review: Nutrient Deficiencies in Adults and Children with Treated and Untreated Celiac Disease.

Nutrient deficiencies are well recognized as secondary consequences of celiac disease (CD) and closely related to the clinical presentation of affected patients. Despite their clinical significance, consensus is lacking on the pattern and frequency of nutrient deficiencies in CD, the usefulness of their assessment at the time of diagnosis and during follow-up. This review aims to provide an overview of nutrient deficiencies among pediatric and adult CD patients at diagnosis and on a gluten-free diet (GFD), and their potential causes in CD. Secondly, we review their impact on CD management strategies including the potential of nutrient supplementation. A search of Medline, Pubmed and Embase until January 2019 was performed. Despite a high variability between the reported deficiencies, we noted that nutrient deficiencies occur frequently in children and adults with CD at diagnosis and during treatment with a GFD. Both inadequate dietary intake and/or diminished uptake due to intestinal dysfunction contribute to nutrient deficiencies. Most deficiencies can be restored with (long-term) treatment with a GFD and/or supplementation. However, some of them persist while others may become even more prominent during GFD. Our results indicate a lack of comprehensive evidence on the clinical efficacy of nutrient supplementation in CD management highlighting the need for further studies.

Intestinal TG3- and TG2-Specific Plasma Cell Responses in Dermatitis Herpetiformis Patients Undergoing a Gluten Challenge.

Dermatitis herpetiformis (DH), a cutaneous manifestation of coeliac disease, is characterized by transglutaminase (TG) 3-targeted dermal immunoglobulin A (IgA) deposits. The treatment for DH is the same as for coeliac disease, namely a life-long gluten-free diet. DH patients typically have gluten-dependent circulating autoantibodies targeting TG3 and TG2, and plasma cells secreting such autoantibodies have been detected in the small intestinal mucosa. This study investigates the gluten-responsiveness of intestinal TG3 and TG2 antibody-secreting plasma cells in 16 treated DH patients undergoing a gluten challenge. The frequency of both plasma cell populations increased significantly during the challenge, and their frequency correlated with the corresponding serum autoantibody levels at post-challenge. TG3-specific plasma cells were absent in all 18 untreated coeliac disease patients and seven non-coeliac control subjects on gluten-containing diets. These findings indicate that, in DH, both intestinal TG3- and TG2-antibody secreting plasma cells are gluten-dependent, and that TG3-antibody secreting plasma cells are DH-specific.

Epitope mapping of anti‐amelogenin IgA in coeliac disease

Previously we detected increased levels of IgA to the enamel matrix protein amelogenin in children with untreated coeliac disease (CeD). The biological impact of autoantibodies to amelogenin may depend on which part of the amelogenin (epitopes) they bind. Sera or blood samples from 146 untreated children with CeD from two different cohorts and 25 non-CeD control children were tested for IgA anti-amelogenin (Emdogain) reactivity. The 32 CeD children and six controls with the highest reactivity were selected for detailed IgA anti-amelogenin (AMELX) epitope mapping using 31 overlapping, 10-22mer peptides in ELISA. The dominating reactivity were to six peptides in a 75-amino-acid (aa)-long central segment (aa 75-150) containing enzymatic cleavage sites for matrix metalloproteinase 20 (MMP-20) and kallikrein-related peptidase 4 (KLK-4) and to two N-terminal peptides (aa 13-41) included in the tyrosine-rich amelogenin peptide fragment, which is important for self-assembly. Only two of the six control children reacted to single, but different peptides. Solid-phase extraction with gliadin- and Emdogain-coated Sepharose revealed a gliadin cross-reactive central region and a putative conformation-dependent, apparently non-cross-reactive N-terminal region. High IgA anti-amelogenin reactivity may interfere with normal amelogenesis by inhibiting amelogenin self-assembly, amelogenin-hydroxyapatite interaction, and/or enzymatic degradation.

Faecal calprotectin concentration in children with coeliac disease.

IntroductionIt is still unknown whether faecal calprotectin elevation may be caused by active untreated coeliac disease (CD) itself or whether it indicates the coexistence of CD and another disease associated with gastrointestinal inflammation.AimTo assess faecal calprotectin concentration (FCC) and its correlation with the clinical form and histopathological picture of the small intestine in children with CD.Material and methodsFifty-five children with newly recognised CD (mean age: 9.1 years) and 17 children with CD diagnosed at least year before and on a strict gluten-free diet (mean age: 12.3 years) were accepted for the study. Classical (n = 27), non-classical (n = 17), and asymptomatic form (n = 11) were distinguished in children with newly diagnosed CD based on the clinical picture. The histopathological small intestinal lesions were classified as Marsh 1 (n = 4), 3a (n = 5), 3b (n = 20), and 3c (n = 26). FCC was assessed using ELISA method with 50 µg/g as the upper limit of the normal.ResultsFCC was abnormal for 21 patients with newly diagnosed CD (38.2%) and for six patients from the treated group (35.3%). Mean FCC for the analysed group of patients was 91.7 ±144.8 µg/g, in the group with newly diagnosed CD – 100.9 ±154.4 µg/g, and in the treated group – 61.8 ±106.2 µg/g (Z = –1.333; p = 0.183). In the group of patients with recently diagnosed CD a statistically significant relationship was not observed for FCC and both clinical picture (χ2 = 0.319, p = 0.852) and severity of small intestinal lesions according to the Marsh classification (rho = 0.136).ConclusionsAssessment of FCC seems to have no use as a marker for diagnostics and monitoring of CD irrespective of clinical form of the disease and severity of the inflammatory lesions within the small intestine.

Comparison of thyroid disease prevalence in patients with celiac disease and controls.

This study aimed to investigate the prevalence of thyroid disease (TD) in untreated CD patients and to evaluate the effect of gender and age on its prevalence. Celiac disease (CD) is a form of intestinal malabsorption syndrome which is closely related to endocrine disorders, especially autoimmune thyroid disease and diabetes. The prevalence of TD is possibly high among patients with CD which necessitates the need for screening for TD among them. This comparative cross-sectional study was conducted on 288 consecutive untreated patients with CD (mean age, 27.9±14) and 250 controls (mean age, 29.01±13.15) referred for endoscopy in a hospital located in Iran. Thyroid function was evaluated by measuring T3, T4, and TSH levels using ELISA technique, and testing anti-thyroperoxidase (anti-TPO) antibodies through electrochemiluminescence method. Data analysis was conducted in SPSS v.22 software using descriptive statistics and chi-squared test. Thyroid disease prevalence was 4-fold higher in patients than in controls (13.6% vs. 3.2%, p<0.05). Hypothyroidism was diagnosed in 30 patients and 7 controls, while hyperthyroidism was observed in 9 patients and in one control. Chi-squared test results reported a significant difference in TD prevalence between patients and controls based on gender and age (p<0.05). In both groups, women were significantly more affected than men, and the TD prevalence was higher in younger patients compared to adults. There was a strong association between thyroid dysfunction and CD. In this regard, it is necessary to screen patients for TD.

Increased fasting small-bowel water content in untreated coeliac disease and scleroderma as assessed by magnetic resonance imaging.

The regular overnight migrating motor complex (MMC) ensures that the normal fasting small-bowel water content (SBWC) is minimised. We have applied our recently validated non-invasive magnetic resonance technique to assess SBWC in newly diagnosed coeliac disease (CD), scleroderma (SCD) and irritable bowel syndrome (IBS), conditions possibly associated with small intestinal bacterial overgrowth (SIBO). A total of 20 CD and 15 SCD patients with gastrointestinal symptoms were compared to 20 healthy volunteers (HV) and 26 IBS with diarrhoea (IBS-D) patients, as previously reported. All underwent a fasting magnetic resonance imaging (MRI) scan on a 1.5 T Philips Achieva MRI scanner to assess fasting SBWC and colonic volumes. Stool and symptom diaries were completed for one week. Compared to HV, all patients had significantly increased stool frequency and Bristol stool form score. SBWC was significantly increased in CD (median 109 mL; interquartile range (IQR) 53-224 mL) compared to HV (median 53 mL; IQR 31-98 mL; p < 0.01) and IBS-D (median 42 mL; IQR 28-67 mL; p < 0.01). A variable increase in SBWC was also found in SCD (median 77 mL; IQR 39-158 mL), but this was not significant (p = 0.2). Colonic volumes were similar for all groups, being a median of 547 mL (IQR 442-786 mL) for CD, 511 mL (453-789 mL) for SCD, 612 mL (445-746 mL) for HV and 521 mL (428-757 mL) for IBS-D. When CD patients were subdivided according to the Marsh classification, the higher grades had larger colonic volumes. Fasting SBWC as assessed by MRI is significantly increased in newly diagnosed CD and SCD but decreased in IBS-D. Future studies should test whether increased resting fluid predisposes to SIBO.

Single-cell TCR sequencing of gut intraepithelial γδ T cells reveals a vast and diverse repertoire in celiac disease.

A hallmark of celiac disease (CeD), a chronic condition driven by cereal gluten exposure, is increase of gut intraepithelial γδ T cells. This may indicate pathogenic involvement of γδ T cells and existence of disease-specific γδ T-cell receptors (TCRs) recognizing defined antigen(s). We performed high-throughput and paired γδ TCR sequencing of single intraepithelial γδ T cells of untreated CeD patients (n = 8; 1821 cells), CeD patients treated with a gluten-free diet (n = 5; 436 cells) and controls (n = 7; 1068 cells). We found that CeD patients, both untreated and treated, had larger and more diverse γδ TCR repertoires, more frequent usage of TRDV1 and TRDV3 and different patterns of TCRγ/TCRδ-pairing compared with controls. Although we observed no public CDR3δ sequences, there were several public CDR3γ sequences-many of which were shared by not only the CeD patients, but also by the controls. These public CDR3s were characterized by few N/P nucleotide insertions with germline and near-germline configuration, hence being easy to generate. Previous findings of CeD-specific CDR3 motifs were not replicated. Thus, being unable to raise evidence for CeD-specific γδ TCRs in this first large, paired γδ TCR single-cell sequencing study, we project challenges for identification of CeD-relevant γδ TCR ligands.