Impact of Cigarette Smoking on Clinical Presentation and Treatment Response in Coeliac Disease.

BACKGROUND AND AIMS: The environmental factors, apart from gluten ingestion predisposing to coeliac disease are poorly known. Smoking is associated with many immune-mediated diseases, but research on coeliac disease is scarce. This study aims to investigate how smoking affects the clinical presentation, presence of comorbidities and response to gluten-free diet in coeliac disease. METHODS: Altogether 815 adults with coeliac disease participated in a nationwide cross-sectional study. Participants were interviewed and smoking habits (never, former, or current smoker), clinical presentation of coeliac disease and presence of comorbidities were elicited. Serology and severity of small bowel mucosal lesions at diagnosis were gathered from the participants' medical records and follow-up serology was measured. Gastrointestinal symptoms and psychological well-being were assessed using validated questionnaires. RESULTS: Current smokers were more often male and were diagnosed at younger ages than never or former smokers. There were no differences between the groups in clinical presentation, severity of symptoms or mucosal lesions at diagnosis or in dietary compliance and clinical, serological, and histological recovery. Musculoskeletal disorders, particularly osteoporosis and osteopenia, were more common in never smokers than in other groups (14.5% vs. 5.1% and 4.1%, p<0.001), and cardiovascular disorders were diagnosed more often in former smokers (36.2% vs. 23.5% and 21.9%, p=0.003). CONCLUSIONS: Smoking does not seem to have an impact on the clinical presentation, severity of symptoms or mucosal damage in coeliac disease. Histological and clinical recovery as well as seroconversion on gluten-free diet are not affected by smoking status.

Celiac Disease Affects 1% of Global Population: Who Will Manage All These Patients?

Celiac disease is a common gastrointestinal condition with an estimated global prevalence of up to 1%. Adequate long-term surveillance of patients is imperative to ensure strict adherence to treatment with a gluten-free diet and the ensuing clinical and histologic recovery. Traditionally, this has been accomplished by means of regular on-site attendance at specialist health care facilities, accompanied for most patients by follow-up endoscopic and laboratory tests. However, the rapidly increasing prevalence of celiac disease and the limited health care resources challenge the current centralized and nonindividualized follow-up strategies. The improved noninvasive surveillance tools and online health care services are further changing the landscape of celiac disease management. There is a clear need for more personalized and on-demand follow-up based on early treatment response and patient-related factors associated with long-term prognosis. Additional scientific evidence on the optimal implementation of follow-up for pediatric and adulthood celiac disease is nevertheless called for.

Measured levels of positive transglutaminase 2 antibodies are not associated with presentation or incidental endoscopic findings at celiac disease diagnosis.

OBJECTIVES: It has been suggested that celiac disease could be diagnosed non-invasively in adults with transglutaminase antibody (TGA) levels >10x upper limit of normal (ULN). It is, however, unclear if high values signify more advanced disease and higher risk of co-morbidities. We investigated the association between the TGA levels, clinical characteristics and non-celiac endoscopic findings. METHODS: Medical data on 450 celiac disease patients at diagnosis were collected. They were further divided into those with high positive (>10x ULN, n = 164), moderately positive (1-10x ULN, n = 219), and negative (n = 67) TGA. RESULTS: Median age of patients was 50 years and 60% were women. Patients with negative TGA were older (median age 58 vs. 51 vs. 46 years respectively, p = 0.002) and had more often weight loss (27% vs. 10% vs. 9%, p < 0.001) and abdominal pain or dyspepsia (40% vs 27% vs. 22%, p = 0.017) than did those with moderately positive/high TGA. The groups did not differ in sex, BMI, or other symptoms. Major endoscopic findings included one esophageal adenocarcinoma presenting with dysphagia, six esophagitis, three gastric ulcers, and 39 H. Pylori or other active gastritis. High, moderately positive or negative TGA levels were not associated with these findings in crude or age-adjusted analyses. CONCLUSIONS: Presentation was similar in patients with moderate or high levels of TGA, whereas patients with negative TGA were different. The level of TGA was not associated with incidental endoscopic findings and the only malignancy presented with an alarm symptom atypical to celiac disease.

Risk of vascular diseases in patients with dermatitis herpetiformis and coeliac disease: a long-term cohort study.

INTRODUCTION: Dermatitis herpetiformis (DH) is a cutaneous manifestation of coeliac disease. Increased cardiovascular morbidity has been reported in coeliac disease, but in DH only little is known about this. In this cohort study with a long-term follow-up, the risk for vascular diseases in patients with dermatitis herpetiformis (DH) and coeliac disease was assessed. METHODS: The study consisted of 368 DH and 1072 coeliac disease patients with biopsy-proven diagnosis performed between 1966 and 2000. For each DH and coeliac disease patient three matched reference individuals were obtained from the population register. Data regarding all outpatient and inpatient treatment periods between 1970 and 2015 were reviewed for diagnostic codes of vascular diseases from the Care Register for Health Care. Cox proportional hazard model was used to assess the risks for the diseases studied and the HRs were adjusted for diabetes mellitus (aHR). RESULTS: The median follow-up time of DH and coeliac disease patients was 46 years. The risk for cardiovascular diseases did not differ between DH patients and their references (aHR 1.16, 95% CI 0.91-1.47), but among coeliac disease patients, the risk was increased (aHR 1.36, 95% CI 1.16-1.59). The risk for cerebrovascular diseases was found to be decreased in DH patients when compared with references (aHR 0.68, 95% CI 0.47-0.99) and increased in coeliac disease patients (aHR 1.33, 95% CI 1.07-1.66). The risk for venous thrombosis was increased in coeliac disease patients (aHR 1.62, 95% CI 1.22-2.16) but not in DH. CONCLUSIONS: The risk for vascular complications appears to differ between DH and coeliac disease. In DH the risk for cerebrovascular diseases seems to be decreased, while in coeliac disease an elevated risk for cerebrovascular and cardiovascular diseases was observed. These differing vascular risk profiles between the two manifestations of the same disease merit further investigation.

An increased risk for cardiovascular diseases was observed among patients with coeliac disease, but not among patients with dermatitis herpetiformis, a cutaneous manifestation of coeliac disease.The risk for cerebrovascular diseases was shown to be decreased in dermatitis herpetiformis patients, but conversely, an increased risk for cerebrovascular diseases was identified in coeliac disease patients.Coeliac disease, but not dermatitis herpetiformis, was shown to be associated with increased risk for venous thrombosis.

Presence of gastrointestinal symptoms in IgA nephropathy: a cross-sectional study.

BACKGROUND: Gastrointestinal (GI) symptoms are common in end-stage kidney disease. Mounting evidence indicates that the intestine plays an important role in the pathogenesis of IgA nephropathy (IgAN). However, no studies have addressed the obvious question; do IgAN patients suffer from GI symptoms? METHODS: Presence of GI symptoms and health-related quality of life were evaluated using the validated Gastrointestinal Symptom Rating Scale (GSRS) and Psychological General Well-Being (PGWB) questionnaires in 104 patients with kidney biopsy-verified IgAN and in 147 healthy controls. A person was regarded to experience 'increased GI symptoms' if the GSRS score exceeded plus 1 standard deviation of the mean of the corresponding score in the healthy controls. RESULTS: According to the GSRS total score, the IgAN patients had more GI symptoms than the healthy controls (2.0 vs. 1.7, p < 0.001). Female IgAN patients had higher GSRS total score than male patients (2.2 vs. 1.7, p = 0.001). More IgAN patients with preserved kidney function (eGFR > 60ml/min/1.73m2) suffered from increased symptoms of diarrhoea (76 vs. 25%, p = 0.028), constipation (81 vs. 19%, p = 0.046) and reflux (85 vs. 15%, p = 0.004) than did IgAN patients with reduced kidney function (eGFR < 60ml/min/1.73m2). CONCLUSIONS: IgAN patients and especially female IgAN patients experienced more GI symptoms than healthy controls. More prevalent GI symptoms were already observed before kidney function was clearly reduced. Systematic enquiry of GI symptoms might increase the standard of care among IgAN patients. Moreover, GI symptoms may provide clues for future studies that examine the pathophysiology of IgAN.

Association of concomitant autoimmunity with the disease features and long-term treatment and health outcomes in Celiac disease.

Background: Celiac disease (CeD) is often accompanied by other autoimmune diseases (AID). However, the association of co-existing autoimmunity with the presentation and treatment success in CeD is unclear. We investigated these issues with a large and well-defined cohort of Finnish patients. Methods: Adult CeD patients (n = 806) were collected from multiple heath care sites via nationwide recruitment. They were interviewed, underwent measurement of CeD autoantibodies, and filled out questionnaires to ascertain quality of life (PGWB) and gastrointestinal symptoms (GSRS) after a median of 9.7 years on a gluten-free diet. Data were supplemented retrospectively from patient records. The results were compared between CeD patients with and without a coexisting AID. Results: Altogether 185 patients had CeD+AID and 621 had CeD only. At CeD diagnosis, patients with CeD+AID were older (median 42 vs. 36 years, p = 0.010) and had more joint symptoms (9.1 vs. 4.2%, p = 0.011), whereas the groups were comparable in sex, family history of CeD, other presenting symptoms, proportion of screen-detected subjects, and severity of duodenal lesion. During follow-up on gluten-free diet, CeD+AID patients experienced poorer general health (median score 12 vs. 14, p < 0.001) in PGWB, more overall gastrointestinal symptoms (2.1 vs. 1.9, p = 0.001), and constipation (2.0 vs. 1.7, p < 0.001) in GSRS, whereas there was no difference in histological and serological recovery, dietary adherence, use of gluten-free oats, smoking, and presence of regular follow-up. Conclusions: Co-existing AID was not significantly associated with the baseline features or with most long-term outcomes in CeD. However, the increased prevalence of gastrointestinal symptoms and reduced poorer self-perceived health during treatment indicates these patients' need for special support.

Review article: Systemic consequences of coeliac disease.

BACKGROUND: The best-known symptoms of coeliac disease are related to the gastrointestinal tract, but the disease may also present with various systemic manifestations outside the intestine. Some of these consequences may remain permanent in undiagnosed individuals or if the diagnostic delay is prolonged. However, for many of the systemic manifestations, the scientific evidence remains scant and contradictory. AIMS AND METHODS: We conducted a narrative review of the most thoroughly studied and clinically relevant systemic consequences of coeliac disease, especially those that could be prevented or alleviated by early diagnosis. The review is intended particularly for physicians encountering these patients in daily clinical practice. RESULTS: The possible systemic consequences of coeliac disease extend to multiple organ systems, the best studied of which are related to skeletal, reproductive, cardiovascular and neurological systems. Furthermore, the disease is associated with an elevated risk of psychiatric comorbidities, non-Hodgkin lymphomas and intestinal adenocarcinoma. CONCLUSIONS: The various systemic consequences of coeliac disease play a significant role in the overall health of patients. Early diagnosis and treatment with a gluten-free diet appear to be beneficial for most, but not all of these conditions. The possible negative metabolic and psychosocial effects of the diet should be acknowledged during follow-up.

Nomenclature and diagnosis of seronegative coeliac disease and chronic non-coeliac enteropathies in adults: the Paris consensus.

OBJECTIVE: Differential diagnosis of villous atrophy (VA) without coeliac antibodies in adults includes seronegative coeliac disease (CD) and chronic enteropathies unrelated to gluten, ie. non-coeliac enteropathies (NCEs). There is currently no international consensus on the nomenclature and diagnostic criteria for these enteropathies. In this work, a Delphi process was conducted to address this diagnostic and clinical uncertainty. DESIGN: An international task force of 13 gastroenterologists from six countries was recruited at the 16th International Coeliac Disease Symposium, Paris, 2019. Between September 2019 and July 2021, a Delphi process was conducted through mail surveys to reach a consensus on which conditions to consider in the differential diagnosis of VA with negative coeliac serology and the clinical diagnostic approaches required for these conditions. A 70% agreement threshold was adopted. RESULTS: Chronic enteropathies characterised by VA and negative coeliac serology can be attributed to two main clinical scenarios: forms of CD presenting with negative serology, which also include seronegative CD and CD associated with IgA deficiency, and NCEs, with the latter recognising different underlying aetiologies. A consensus was reached on the diagnostic criteria for NCEs assisting clinicians in differentiating NCEs from seronegative CD. Although in adults seronegative CD is the most common aetiology in patients with VA and negative serology, discriminating between seronegative CD and NCEs is key to avoid unnecessary lifelong gluten-free diet, treat disease-specific morbidity and contrast poor long-term outcomes. CONCLUSION: This paper describes the Paris consensus on the definitions and diagnostic criteria for seronegative CD and chronic NCEs in adults.

Gluten Induces Subtle Histological Changes in Duodenal Mucosa of Patients with Non-Coeliac Gluten Sensitivity: A Multicentre Study.

Background: Histological changes induced by gluten in the duodenal mucosa of patients with non-coeliac gluten sensitivity (NCGS) are poorly defined. Objectives: To evaluate the structural and inflammatory features of NCGS compared to controls and coeliac disease (CeD) with milder enteropathy (Marsh I-II). Methods: Well-oriented biopsies of 262 control cases with normal gastroscopy and histologic findings, 261 CeD, and 175 NCGS biopsies from 9 contributing countries were examined. Villus height (VH, in µm), crypt depth (CrD, in µm), villus-to-crypt ratios (VCR), IELs (intraepithelial lymphocytes/100 enterocytes), and other relevant histological, serologic, and demographic parameters were quantified. Results: The median VH in NCGS was significantly shorter (600, IQR: 400−705) than controls (900, IQR: 667−1112) (p < 0.001). NCGS patients with Marsh I-II had similar VH and VCR to CeD [465 µm (IQR: 390−620) vs. 427 µm (IQR: 348−569, p = 0·176)]. The VCR in NCGS with Marsh 0 was lower than controls (p < 0.001). The median IEL in NCGS with Marsh 0 was higher than controls (23.0 vs. 13.7, p < 0.001). To distinguish Marsh 0 NCGS from controls, an IEL cut-off of 14 showed 79% sensitivity and 55% specificity. IEL densities in Marsh I-II NCGS and CeD groups were similar. Conclusion: NCGS duodenal mucosa exhibits distinctive changes consistent with an intestinal response to luminal antigens, even at the Marsh 0 stage of villus architecture.

Coeliac disease re-screening among once seronegative at-risk relatives: A long-term follow-up study.

BACKGROUND: Serological screening of the relatives of coeliac disease patients is widely endorsed. However, the need for and the optimal timing of possible re-testing of once seronegative at-risk individuals for coeliac disease remain unclear. OBJECTIVE: We investigated this issue by inviting a large cohort of previously screening-negative relatives of patients with coeliac disease to participate in a follow-up study. METHODS: Altogether 599 relatives of coeliac disease index patients not diagnosed with coeliac disease in a screening study carried out in 2006-2010 were asked about possible later diagnosis or re-tested with coeliac disease autoantibodies in 2017-2021. Besides incidence, the possible impact of various patient-related clinical factors and HLA haplotype on the later diagnosis or screening positivity was examined. RESULTS: Fifteen (2.5%) relatives were either diagnosed with a coeliac disease (n = 8) during the follow-up period or were found to be screening-positive in the re-testing (n = 7), giving a combined annual incidence of 221/100,000 person-years in all relatives and 336/100,000 among those carrying coeliac disease-associated HLA DQ2/DQ8. The new cases more often carried the high-risk (DQ2.5/2.5 or DQ2.5/2.2; 35.7% vs. 7.4%, respectively, p < 0.001) HLA and were younger at initial screening (23.3 vs. 40.5 years, p = 0.028) and - in spite of a negative screening outcome - had higher median transglutaminase antibody level in the first study than those not affected. There were no significant differences between the affected and non-affected relatives in other demographic data, degree of kinship with the index, current symptoms or frequency of chronic co-morbidities. CONCLUSION: The incidence rate for later coeliac disease diagnosis or new seropositivity in relatives who had been tested once was 221/100,000 person-years in all and 336/100,000 among those carrying at-risk HLA genetics after ∼10 years of follow-up. HLA-typing could help to target a subgroup of relatives who would benefit most from re-testing.

Mortality and causes of death in different celiac disease phenotypes during long-term follow-up.

BACKGROUND: Celiac disease has been associated with increased mortality, but data on long-term mortality are scarce. AIMS: To determine long-term mortality in celiac disease. METHODS: The study cohort consisted of all celiac disease patients (n=1,392) diagnosed in Tampere University Hospital catchment area 1960 - 2000. Patients were categorized into subgroups based on demographic (age, gender, decade of diagnosis) and celiac disease characteristics (e.g., phenotype, severity of villous atrophy) collected from medical records. Overall and cause-specific mortality was compared to those of age-, sex-, and place of residence matched reference individuals (n=4,177) over time. RESULTS: During the 41 years of follow-up (median 26.5 years), 376 celiac disease patients and 1,155 reference individuals died. All-cause mortality was not increased (hazard ratio (HR) 0.96, 95% confidence intervals (CI) 0.85-1.08). Mortality from lymphoproliferative diseases and diseases of the central nervous system was increased (HR 2.42, 95% CI 1.38-4.24 and HR 2.14, 95% CI 1.05-4.36 respectively) while the risk from alcohol related diseases was decreased (HR 0.31, 95% CI 0.09-1.00). Examination of various celiac disease phenotypes revealed no significant differences in mortality CONCLUSIONS: Overall mortality was not increased in any celiac disease phenotype during a very long-term follow-up.

Clinical Relevance of Anti-Gliadin Seropositivity in the Ageing Population: A Long-term Follow-up Study.

AIMS: To explore if anti-gliadin antibody (AGA) positivity is associated with overall mortality or morbidity and especially with the development of coeliac disease during long-term gluten exposure. METHODS: The study population comprised 130 persistently AGA-positive but transglutaminase-2 (anti- TG2) -negative and 52 persistently AGA- and anti-TG2 -negative subjects aged 64-88 years. HLA-typing for DQ2 and DQ8 (coeliac-type HLA) was performed on the AGA-positives. The medical records of the study population were reviewed to compare mortality and morbidity during a long-term follow-up of 12-13 years since the initial antibody analysis. RESULTS: Mortality or cumulative prevalence of gastroenterological, autoimmune, psychiatric, cardiovascular or any malignant diseases did not differ statistically between the AGA-positives and the AGA-negatives. Neurological diseases were more common in the AGA-negative group (p=0.017), but there was no statistical difference between the prevalence of any particular neurological diseases. Coeliac-type HLA in AGA-positive subjects did not influence mortality or morbidity. However, during the last six to seven years the incidence of immunological diseases was more common in the AGA-positive subjects without coeliac-type HLA than in those with coeliac-type HLA, or in the AGA-negative group (p=0.020). None of the persistently AGA-positive subjects developed clinically diagnosed coeliac disease. CONCLUSIONS: Gliadin antibody positivity without coeliac disease does not predict mortality or morbidity in the ageing population continuing to consume gluten for over ten years.

Toward Xeno-Free Differentiation of Human Induced Pluripotent Stem Cell-Derived Small Intestinal Epithelial Cells.

The small intestinal epithelium has an important role in nutrition, but also in drug absorption and metabolism. There are a few two-dimensional (2D) patient-derived induced pluripotent stem cell (iPSC)-based intestinal models enabling easy evaluation of transcellular transport. It is known that animal-derived components induce variation in the experimental outcomes. Therefore, we aimed to refine the differentiation protocol by using animal-free components. More specifically, we compared maturation of 2D-cultured iPCSs toward small intestinal epithelial cells when cultured either with or without serum, and either on Geltrex or on animal-free, recombinant laminin-based substrata. Differentiation status was characterized by qPCR, immunofluorescence imaging, and functionality assays. Our data suggest that differentiation toward definitive endoderm is more efficient without serum. Both collagen- and recombinant laminin-based coating supported differentiation of definitive endoderm, posterior definitive endoderm, and small intestinal epithelial cells from iPS-cells equally well. Small intestinal epithelial cells differentiated on recombinant laminin exhibited slightly more enterocyte specific cellular functionality than cells differentiated on Geltrex. Our data suggest that functional small intestinal epithelial cells can be generated from iPSCs in serum-free method on xeno-free substrata. This method is easily converted to an entirely xeno-free method.

Role of HLA-DQ typing and antitissue transglutaminase antibody titres in diagnosing coeliac disease among Sudanese children with type 1 diabetes mellitus.

OBJECTIVE: The aim of the study was to determine the prevalence of coeliac disease (CD) and to recognise Human leukocyte antigen (HLA)-associated hereditary susceptibility to Sudanese CD patients with type 1 diabetes mellitus (DM1). DESIGN: Antitissue transglutaminase IgA (anti-TG IgA) was measured in the serum of 373 children affected with DM1 aged 1-19-year old and in 100 serum samples from non-diabetic control children. Histological examination was performed in 19 children seropositive for anti-TG IgA (17 DMI and 2 controls). Additionally, PCR-based analysis of Major histocompatibility complex, class II, DQ beta 1 (HLA-DQB1) genotyping was implemented in three study population groups as follows: group 1 (n=25) (+ve DM1 and +ve CD), group 2 (n=63) (-ve DM1 and +ve CD) and control group 3 (n=2) (+ve CD). RESULTS: Twenty-six Sudanese children with DM1 out of 373 (6.97%) were seropositive for anti-TG IgA. Duodenal biopsy revealed Marsh 2 and 3 in 13 out of 17 (76.47%) seropositive anti-TG IgA patients with DM1. Significant association (p<0.05) was detected between the level of anti-TG IgA autoantibodies (IU/mL) and Marsh stage. HLA DQ2 and DQ8 were found in 88% (22/25) and 8% (2/25) of examined patients with CD with DM1, respectively. CONCLUSIONS: Anti-TG IgA titre of greater than 10 times upper limit of normal (≥10× ULN) can be useful for detecting CD in children with type 1 diabetes without duodenal biopsy. HLA testing in children with DM1 appears to provide little added benefit given the high prevalence (96%) of HLA DQ2/DQ8 in children with DM1.

Celiac Disease-Type Tissue Transglutaminase Autoantibody Deposits in Kidney Biopsies of Patients with IgA Nephropathy.

An association between celiac disease and IgA nephropathy (IgAN) has been suggested. In celiac disease, in addition to circulating in serum, IgA-class tissue transglutaminase (tTG) autoantibodies are deposited in the small bowel mucosa and extraintestinal organs. In this case series of IgAN patients with or without celiac disease, we studied whether celiac disease-type IgA-tTG deposits occur in kidney biopsies. The study included nine IgAN patients, four of them with celiac disease. At the time of the diagnostic kidney biopsy serum tTG autoantibodies were measured and colocalization of IgA and tTG was investigated in the frozen kidney biopsies. Three IgAN patients with celiac disease had IgA-tTG deposits in the kidney even though in two of these the celiac disease diagnosis had been set years later. These deposits were not found in a patient with already diagnosed celiac disease following a gluten-free diet. Of the five non-celiac IgAN patients, three had IgA-tTG deposits in the kidney. We conclude that tTG-targeted IgA deposits can be found in the kidney biopsies of gluten-consuming IgAN patients but their specificity to celiac disease seems limited.

Iron Transporter Protein Expressions in Children with Celiac Disease.

Anemia is a frequent finding in children with celiac disease but the detailed pathophysiological mechanisms in the intestine remain obscure. One possible explanation could be an abnormal expression of duodenal iron transport proteins. However, the results have so far been inconsistent. We investigated this issue by comparing immunohistochemical stainings of duodenal cytochrome B (DCYTB), divalent metal transporter 1 (DMT1), ferroportin, hephaestin and transferrin receptor 1 (TfR1) in duodenal biopsies between 27 children with celiac disease and duodenal atrophy, 10 celiac autoantibody-positive children with potential celiac disease and six autoantibody-negative control children. Twenty out of these 43 subjects had anemia. The expressions of the iron proteins were investigated with regard to saturation and the percentage of the stained area or stained membrane length of the enterocytes. The results showed the stained area of ferroportin to be increased and the saturation of hephaestin to be decreased in celiac disease patients compared with controls. There were no differences in the transporter protein expressions between anemic and non-anemic patients. The present results suggest an iron status-independent alteration of ferroportin and hephaestin proteins in children with histologically confirmed celiac disease.

Prevalence of Inflammatory Bowel Disease and Celiac Disease in Patients with IgA Nephropathy over Time.

INTRODUCTION: IgA nephropathy (IgAN) has been connected with increased intestinal permeability and subclinical intestinal mucosal inflammation as well as with inflammatory bowel disease (IBD) and celiac disease - nevertheless, the results are controversial. The prevalence of bowel diseases has increased over time in Western populations. Whether similar trend is seen among IgAN patients remains obscure. Our aim was to study the prevalence of IBD and celiac disease in IgAN patients over time. METHODS: The study cohort consisted of altogether 629 patients with newly diagnosed IgAN during years 1976-2012. Data on diagnosis of IBD and celiac disease were retrospectively collected from medical records. Further, to detect unrecognized celiac disease, IgA-class tissue transglutaminase antibodies (tTGA) were measured from serum samples taken at the time of kidney biopsy during years 1980-2012 (defined as screen-detected celiac disease autoimmunity). RESULTS: The prevalence of IBD among IgAN patients increased over time from 0 to 4.4%, while the prevalence of clinically diagnosed celiac disease decreased from 2.6 to 0.6%. Moreover, the number of screen-detected tTGA-positive cases decreased from the 1980s to the 21st century (2.8-0.7%). CONCLUSION: The prevalence of IBD increased over time in IgAN patients, which exceeds the prevalence of 0.6% in Finnish general population. In parallel, the prevalence of celiac disease and screen-detected celiac disease autoimmunity decreased over time. The coexistence of IBD and IgAN is not negligible. Whether this finding is caused by the increase in the prevalence of IBD in the population or shared pathophysiology between IgAN and IBD remains a matter of further studies.

Effects of In Vivo Gluten Challenge on PBMC Gene Expression Profiles in Diet Treated Celiac Disease.

The pathological mechanisms that lead to the onset and reactivation of celiac disease (CD) remain largely unknown. While gluten free diet (GFD) improves the intestinal damage and associated clinical symptoms in majority of cases, it falls short of providing full recovery. Additionally, late or misdiagnosis is also common as CD presents with a wide range of symptoms. Clear understanding of CD pathogenesis is thus critical to address both diagnostic and treatment concerns. We aimed to study the molecular impact of short gluten exposure in GFD treated CD patients, as well as identify biological pathways that remain altered constitutively in CD regardless of treatment. Using RNAseq profiling of PBMC samples collected from treated CD patients and gluten challenged patient and healthy controls, we explored the peripheral transcriptome in CD patients following a short gluten exposure. Short gluten exposure of just three days was enough to alter the genome-wide PBMC transcriptome of patients. Pathway analysis revealed gluten-induced upregulation of mainly immune response related pathways, both innate and adaptive, in CD patients. We evaluated the perturbation of biological pathways in sample-specific manner. Compared to gluten exposed healthy controls, pathways related to tight junction, olfactory transduction, metabolism of unsaturated fatty acids (such as arachidonic acid), metabolism of amino acids (such as cysteine and glutamate), and microbial infection were constitutively altered in CD patients regardless of treatment, while GFD treatment appears to mostly normalize immune response pathways to "healthy" state. Upstream regulator prediction analysis using differentially expressed genes identified constitutively activated regulators relatively proximal to previously reported CD associated loci, particularly SMARCA4 on 19p13.2 and CSF2 on 5q31. We also found constitutively upregulated genes in CD that are in CD associated genetic loci such as MEF2BNB-MEF2B (BORCS8-MEF2B) on 19p13.11 and CSTB on 21q22.3. RNAseq revealed strong effects of short oral gluten challenge on whole PBMC fraction and constitutively altered pathways in CD PBMC suggesting important factors other than gluten in CD pathogenesis.