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.

Nonbiopsy Approach for Celiac Disease Is Accurate When Using Exact Duodenal Histomorphometry: Prospective Study in 2 Countries.

GOALS: To test the accuracy of serology-based criteria for diagnosing celiac disease utilizing quantitative histomorphometry. BACKGROUND: The revised European pediatric guidelines allow noninvasive celiac disease diagnosis for a subgroup of children. However, in some of the studies on this issue, the positive predictive value (PPV) of serology has remained suboptimal, possibly because of challenges of histopathology as the reference standard. STUDY: Prospectively enrolled children with transglutaminase 2 antibodies (TGA) above the upper limit of normal (ULN) underwent blood sampling and duodenal biopsy in Finland and Romania. Those with TGA ≥10× ULN, positive endomysium antibodies (EmA), and disease-associated genetics were considered to fulfill triple criteria for celiac disease. Initial histopathologic analysis was conducted using grouped classification, whereupon centralized morphometry was performed. RESULTS: Altogether 88 (54%) children were triple positive. In local evaluation, 99% of triple-positive children and 73% of children with TGA <10× ULN had celiac disease. These figures increased to 100% and 85% after more precise morphometric analysis. Triple-positive children had more anemia and higher median EmA and liver enzyme values than those with TGA<10× ULN; the groups were comparable in other clinical features and laboratory parameters. CONCLUSIONS: When applied as recommended, the nonbiopsy strategy had already yielded excellent PPV regardless of the site of diagnosis or clinical presentation in the local analysis. PPV further increased to 100% with standardized duodenal morphometry.

Non-Biopsy Serology-Based Diagnosis of Celiac Disease in Adults Is Accurate with Different Commercial Kits and Pre-Test Probabilities.

Non-biopsy diagnosis of celiac disease is possible in children with anti-transglutaminase 2 antibodies (TGA) > 10× the upper limit of normal (ULN) and positive anti-endomysial antibodies (EMA). Similar criteria have been suggested for adults, but evidence with different TGA assays is scarce. We compared the performance of four TGA tests in the diagnosis of celiac disease in cohorts with diverse pre-test probabilities. Serum samples from 836 adults with either clinical suspicion or family risk of celiac disease were tested with four commercial TGA assays, EmA and celiac disease-associated genetics. The diagnosis was set based on duodenal lesion or, in some cases, using special methods. 137 (57%) patients with clinical suspicion and 85 (14%) of those with family risk had celiac disease. Positive predictive value (PPV) for 10×ULN was 100% in each TGA test. The first non-diagnostic investigations were encountered with ULN 1.0×-5.1× in the clinical cohort and 1.3×-4.9× in the family cohort, respectively. Using the assays' own cut-offs (1×ULN) the PPVs ranged 84-100%. Serology-based diagnosis of celiac disease was accurate in adults using different commercial kits and pre-test probabilities using 10×ULN. The results also suggest that the ULN threshold for biopsy-omitting approach could be lower.

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.

Automatic classification of IgA endomysial antibody test for celiac disease: a new method deploying machine learning.

Widespread use of endomysial autoantibody (EmA) test in diagnostics of celiac disease is limited due to its subjectivity and its requirement of an expert evaluator. The study aimed to determine whether machine learning can be applied to create a new observer-independent method of automatic assessment and classification of the EmA test for celiac disease. The study material comprised of 2597 high-quality IgA-class EmA images collected in 2017-2018. According to standard procedure, highly-experienced professional classified samples into the following four classes: I - positive, II - negative, III - IgA deficient, and IV - equivocal. Machine learning was deployed to create a classification model. The sensitivity and specificity of the model were 82.84% and 99.40%, respectively. The accuracy was 96.80%. The classification error was 3.20%. The area under the curve was 99.67%, 99.61%, 100%, and 99.89%, for I, II, III, and IV class, respectively. The mean assessment time per image was 16.11 seconds. This is the first study deploying machine learning for the automatic classification of IgA-class EmA test for celiac disease. The results indicate that using machine learning enables quick and precise EmA test analysis that can be further developed to simplify EmA analysis.

Gluten Challenge Induces Skin and Small Bowel Relapse in Long-Term Gluten-Free Diet-Treated Dermatitis Herpetiformis.

Dermatitis herpetiformis (DH) is an extraintestinal manifestation of celiac disease causing an itchy, blistering rash. Granular IgA deposits in the skin are pathognomonic for DH, and the treatment of choice is a lifelong gluten-free diet (GFD). Preliminary evidence suggests that there are patients with DH who redevelop gluten tolerance after adherence to a GFD treatment. To evaluate this, we performed a 12-month gluten challenge with skin and small-bowel mucosal biopsy samples in 19 patients with DH who had adhered to a GFD for a mean of 23 years. Prechallenge biopsy was negative for skin IgA and transglutaminase 3 deposits in 16 patients (84%) and indicated normal villous height-to-crypt depth ratios in the small bowel mucosa in all 19 patients. The gluten challenge caused a relapse of the rash in 15 patients (79%) in a mean of 5.6 months; of these 15 patients, 13 had skin IgA and transglutaminase 3 deposits, and 12 had small-bowel villous atrophy. In addition, three patients without rash or immune deposits in the skin developed villous atrophy, whereas one patient persisted without any signs of relapse. In conclusion, 95% of the patients with DH were unable to tolerate gluten even after long-term adherence to a GFD. Therefore, lifelong GFD treatment remains justified in all patients with DH.

Serology-based criteria for adult coeliac disease have excellent accuracy across the range of pre-test probabilities.

BACKGROUND: The revised paediatric criteria for coeliac disease allow omission of duodenal biopsies in symptomatic children who have specific serology and coeliac disease-associated genetics. It remains unclear whether this approach is also applicable for adults with various clinical presentations. AIM: To evaluate the accuracy of serology-based criteria in adults with variable pre-test probabilities for coeliac disease. METHODS: Three study cohorts comprised adults with high-risk clinical coeliac disease suspicion (n = 421), moderate-risk family members of coeliac disease patients (n = 2357), and low-risk subjects from the general population (n = 2722). Serological and clinical data were collected, and "triple criteria" for coeliac disease comprised transglutaminase 2 antibodies >10× the upper limit of normal, positive endomysium antibodies, and appropriate genetics without requirement of symptoms. The diagnosis was based on intestinal biopsy. RESULTS: The diagnosis of coeliac disease was established in 274 subjects. Of these, 59 high-risk subjects, 17 moderate-risk subjects, and 14 low-risk subjects fulfilled the "triple criteria". All had histologically proven coeliac disease, giving the criteria a positive predictive value of 100%. Altogether, 90 (33%) of all 274 newly diagnosed patients could have avoided biopsy, including 37% among high-risk, 20% among moderate-risk, and 48% among low-risk patients. No histological findings other than coeliac disease were found in the biopsies of "triple positive" subjects. CONCLUSIONS: Coeliac disease can reliably and safely be diagnosed without biopsy in adults fulfilling the "triple criteria" regardless of the pre-test probability. Revised criteria would enable the number of endoscopies to be reduced by one-third.

Small-intestinal TG2-specific plasma cells at different stages of coeliac disease.

BACKGROUND: In coeliac disease, ingestion of gluten induces the production of transglutaminase 2 (TG2)-targeted autoantibodies by TG2-specific plasma cells present at high frequency in the small intestinal mucosa in untreated disease. During treatment with a gluten-free diet (GFD), the number of these cells decreases considerably. It has not been previously investigated whether the cells are also present prior to development of villous atrophy, or in non-responsive patients and those with dietary lapses. We aimed to define the frequency of small bowel mucosal TG2-specific plasma cells in coeliac disease patients with varying disease activity, and to investigate whether the frequency correlates with serum and small intestinal TG2-targeting antibodies as well as mucosal morphology and the number of intraepithelial lymphocytes. RESULTS: Mucosal TG2-specific plasma cells were found in 79% of patients prior to development of mucosal damage, in all patients with villous atrophy, and in 63% of the patients after 1 year on GFD. In these disease stages, TG2-specific plasma cells accounted for median of 2.3, 4.3, and 0.7% of all mucosal plasma cells, respectively. After long-term treatment, the cells were present in 20% of the patients in clinical remission (median 0%) and in 60% of the patients with poor dietary adherence (median 5.8%). In patients with non-responsive coeliac disease despite strict GFD, the cells were found in only one (9%) subject; the cells accounted for 2.4% of all plasma cells. A positive correlation between the percentage of TG2-specific plasma cells and serum TG2 antibody levels (rS = 0.69, P < 0.001) and the intensity of mucosal TG2-targeting IgA deposits (rS = 0.43, P < 0.001) was observed. CONCLUSIONS: Our results show that TG2-specific plasma cells are already detectable prior to villous atrophy, and that generally their frequency increases during overt disease. By contrast, on GFD, the percentage of these cells decreases. Overall, the presence of TG2-specific plasma cells in the small bowel mucosa mirrors the presence of gluten in the diet, but the frequency is not always parallel to the level of serum or intestinal TG2 antibodies. These findings increase the knowledge about the development of the TG2 plasma cell responses especially in the early phases of coeliac disease.

Long-term follow-up in adults with coeliac disease: Predictors and effect on health outcomes.

INTRODUCTION: Guidelines recommend regular follow-up in coeliac disease, but effect of this on long-term outcomes remains unclear. AIMS: To evaluate predictors and significance of long-term follow-up. METHODS: 677 previously diagnosed coeliac patients were recruited for a nationwide health survey. Medical data were gathered through interviews and patient records. Current symptoms and quality of life were assessed by validated questionnaires and blood samples were drawn for serology. All variables were compared between patients with and without long-term (>2 years) follow-up. RESULTS: 15% had long-term follow-up, median duration 10 years. Predictors (p < 0.05) for the follow-up were immunological (35% vs. 24%) and circulatory (20% vs. 12%) comorbidities, whereas it was less common in subjects with musculoskeletal (23% vs. 34%) comorbidity and those not belonging to any at-risk group (16% vs. 27%). Patients with or without follow-up had comparable age, adherence and ability to manage a gluten-free diet and frequency of seropositivity. Also questionnaire scores paralleled, but those without follow-up reported more overall symptoms (16% vs. 26%). Most patients wished for follow-up. CONCLUSION: Only a minority of patients had regular follow-up. However, patients with and without the follow-up were comparable in most long-term outcomes, indicating that it might not be always necessary. The results call for more personalized follow-up policies in coeliac disease.

Ex vivo Culture of Duodenal Biopsies from Patients with Dermatitis Herpetiformis Indicates that Transglutaminase 3 Antibody Production Occurs in the Gut.

Coeliac disease and dermatitis herpetiformis (DH) are characterized by autoantibodies targeting transglutaminase (TG)2 and TG3, respectively. Previous studies show that TG2 antibodies are produced in the gut and can be assessed in organ culture of small-intestinal biopsies from patients with coeliac disease. Thus far, no studies have investigated TG3 antibodies in organ culture of biopsies from patients with DH, or exploited the method in DH. The aim of this study was to investigate TG3 and TG2 antibody responses in serum and small-intestinal biopsies from patients with DH with active disease, and from those in remission. The majority of patients with DH were negative for both serum and organ culture medium TG2-targeting antibodies. Surprisingly, patients with active DH secreted TG3 antibodies into the culture medium despite seronegativity. In patients secreting high levels of TG3 antibodies into the culture medium, we also detected TG3-antibody-positive cells in the small-intestinal mucosa. These findings suggest that TG3 antibodies can be investigated in the organ culture system and that their secretion occurs in the small intestine, especially in active DH.

A B-Cell Gene Signature Correlates With the Extent of Gluten-Induced Intestinal Injury in Celiac Disease.

BACKGROUND & AIMS: Celiac disease (CeD) provides an opportunity to study autoimmunity and the transition in immune cells as dietary gluten induces small intestinal lesions. METHODS: Seventy-three celiac disease patients on a long-term, gluten-free diet ingested a known amount of gluten daily for 6 weeks. A peripheral blood sample and intestinal biopsy specimens were taken before and 6 weeks after initiating the gluten challenge. Biopsy results were reported on a continuous numeric scale that measured the villus-height-to-crypt-depth ratio to quantify gluten-induced intestinal injury. Pooled B and T cells were isolated from whole blood, and RNA was analyzed by DNA microarray looking for changes in peripheral B- and T-cell gene expression that correlated with changes in villus height to crypt depth, as patients maintained a relatively healthy intestinal mucosa or deteriorated in the face of a gluten challenge. RESULTS: Gluten-dependent intestinal damage from baseline to 6 weeks varied widely across all patients, ranging from no change to extensive damage. Genes differentially expressed in B cells correlated strongly with the extent of intestinal damage. A relative increase in B-cell gene expression correlated with a lack of sensitivity to gluten whereas their relative decrease correlated with gluten-induced mucosal injury. A core B-cell gene module, representing a subset of B-cell genes analyzed, accounted for the correlation with intestinal injury. CONCLUSIONS: Genes comprising the core B-cell module showed a net increase in expression from baseline to 6 weeks in patients with little to no intestinal damage, suggesting that these individuals may have mounted a B-cell immune response to maintain mucosal homeostasis and circumvent inflammation. DNA microarray data were deposited at the GEO repository (accession number: GSE87629; available: https://www.ncbi.nlm.nih.gov/geo/).

Clinical Characteristics and the Dietary Response in Celiac Disease Patients Presenting With or Without Anemia.

BACKGROUND AND AIMS: It remains unclear as to what are the clinical characteristics associated with the presence of anemia at celiac disease diagnosis, and how these are affected by a gluten-free diet. We investigated these issues in a prospective study. METHODS: Clinical and demographic data, small-bowel mucosal histology, serology, and laboratory parameters, body mass index (BMI), and bone mineral density (BMD) both at diagnosis and after 1 year on a gluten-free diet were investigated in 163 adults with celiac disease. Gastrointestinal symptoms and psychological well-being were evaluated by validated Gastrointestinal Symptom Rating Scale and Psychological General Well-Being questionnaires. All study variables were compared between participants with and without anemia at celiac disease diagnosis. RESULTS: Altogether, 23% of the patients had anemia at diagnosis. Anemic patients were more often women (P=0.001) and had more gastrointestinal symptoms (P=0.004) and were less often screen detected (P=0.009). Further, they had higher celiac antibody values (P=0.007) and a lower total iron (P<0.001), BMI (P=0.003), and density of mucosal γδ+ intraepithelial lymphocytes (P=0.033). After 1 year on a gluten-free diet, the anemia group had a lower mucosal villous height-crypt depth ratio (P=0.008) and BMI (P=0.050), and higher antibody values (P=0.012) and densities of CD3 (P=0.008) and αß+ intraepithelial lymphocytes (P=0.022). There was no significant difference between the groups in their bone mineral density, Gastrointestinal Symptom Rating Scale and Psychological General Well-Being. CONCLUSIONS: Celiac patients with anemia had more severe disease than nonanemic patients in terms of the serology and a lower BMI. Further, they evinced a slower histologic response to the dietary treatment. An early diagnosis and careful follow-up are important in these patients.

Anemia and Iron Deficiency in Children With Potential Celiac Disease.

OBJECTIVES: Active screening for celiac disease frequently detects seropositive children with normal villous morphology (potential celiac disease). It remains unclear whether these subjects should be treated. We here investigated the prevalence of anemia and iron deficiency in children with potential and mucosal atrophy celiac disease. METHODS: The prospective study involved 19 children with potential disease, 67 with partial or subtotal villous atrophy (P/SVA), and 16 with total villous atrophy (TVA). Twenty-three healthy children comprised the control group. The groups were compared for various clinical, histological, and laboratory parameters and hepcidin. RESULTS: The prevalence of abnormal parameters was as follows (controls, potential celiac disease, P/SVA, and TVA, respectively): anemia 0%, 15%, 22%, and 63%; low iron 5%, 0%, 14%, and 50%; increased transferrin receptor 1 5%, 16%, 20%, and 47%; low ferritin 0%, 21%, 35%, and 87%; and low transferrin saturation 10%, 11%, 41%, and 71%. One subject had low folate and none had low vitamin B12. The median values for hemoglobin, total iron, ferritin, and transferrin saturation were significantly lower and transferrin receptor 1 values higher in TVA group compared with other groups. After a median of 7 months on a gluten-free diet hemoglobin, total iron, ferritin, and albumin in children with P/SVA exceeded the baseline values in the potential celiac disease group. CONCLUSIONS: The development of anemia and iron deficiency in celiac disease is a continuum and may already be present in children with normal villous morphology, advocating an early diagnosis and possible dietary treatment of these patients.

Transglutaminase 2-specific coeliac disease autoantibodies induce morphological changes and signs of inflammation in the small-bowel mucosa of mice.

Coeliac disease is hallmarked by an abnormal immune reaction against ingested wheat-, rye- and barley-derived gluten and the presence of transglutaminase 2 (TG2)-targeted autoantibodies. The small-bowel mucosal damage characteristic of the disorder develops gradually from normal villus morphology to inflammation and finally to villus atrophy with crypt hyperplasia. Patients with early-stage coeliac disease have TG2-autoantibodies present in serum and small-intestinal mucosa and they may already suffer from abdominal symptoms before the development of villus atrophy. Previously, we have shown that intraperitoneal injections of coeliac patient-derived sera or purified immunoglobulin fraction into mice induce a condition mimicking early-stage coeliac disease. In the current study, we sought to establish whether recombinantly produced patient-derived TG2-targeted autoantibodies are by themselves sufficient for the development of such an experimentally induced condition in immune-compromised mice. Interestingly, mice injected with coeliac patient TG2-antibodies had altered small-intestinal mucosal morphology, increased lamina propria cellular infiltration and disease-specific autoantibodies deposited in the small bowel, but did not evince clinical features of the disease. Thus, coeliac patient-derived TG2-specific autoantibodies seem to be sufficient for the induction of subtle small-bowel mucosal alterations in mice, but the development of clinical features probably requires additional factors such as other antibody populations relevant in coeliac disease.

Severe Alveolar Hemorrhage - What's in it for the Gastroenterologist?

BACKGROUND: Alveolar hemorrhage is a potentially life-threatening condition which is usually managed by the pulmonologist. When considering its etiology, there is a rare association that sets the disease into the hands of the gastroenterologist. CASE PRESENTATION: We report the case of a 48 year-old female who was admitted to the intensive care unit for severe anemia and hemoptysis. On imaging, diffuse pulmonary infiltrates suggestive of alveolar hemorrhage were detected and a diagnosis of pulmonary hemosiderosis was made. She received cortisone therapy and hematologic correction of anemia, with slow recovery. In search of an etiology for the pulmonary hemosiderosis, an extensive workup was done, and celiac disease specific serology was found positive. After confirmation of celiac disease by biopsy, a diagnosis of Lane-Hamilton syndrome was established. The patient was recommended a gluten-free diet and at 6 months follow-up, resolution of anemia and pulmonary infiltrates were observed. CONCLUSION: Although the association is rare, celiac disease should be considered in a patient with idiopathic pulmonary hemosiderosis. In our case, severe anemia and alveolar infiltrates markedly improved with glucocorticoids and gluten-free diet.

Serum transglutaminase 3 antibodies correlate with age at celiac disease diagnosis.

BACKGROUND: Transglutaminase (TG)2 is the autoantigen in celiac disease, but also TG3 antibodies have been detected in the serum of celiac disease patients. AIMS: To investigate the correlations between serum TG3 antibodies and clinical and histological manifestations of celiac disease and to assess gluten-dependency of TG3 antibodies. METHODS: Correlations between serum TG3 antibody levels measured from 119 adults and children with untreated coeliac disease and the demographic data, clinical symptoms, celiac antibodies, histological data and results of laboratory tests and bone mineral densities were tested. TG3 antibodies were reinvestigated in 97 celiac disease patients after 12 months on a gluten-free diet (GFD). RESULTS: TG3 antibody titers were shown to correlate with the age at celiac disease diagnosis. Further, negative correlation with TG3 antibodies and intestinal γδ+ cells at diagnosis and on GFD was detected. Correlations were not detected with the clinical manifestation of celiac disease, TG2 or endomysial autoantibodies, laboratory values, severity of mucosal villous atrophy, associated diseases or complications. TG3 antibody titers decreased on GFD in 56% of the TG3 antibody positive patients. CONCLUSION: Serum TG3 antibody positivity in celiac disease increases as the diagnostic age rises. TG3 antibodies did not show similar gluten-dependency as TG2 antibodies.

A Prospective Study on the Usefulness of Duodenal Bulb Biopsies in Celiac Disease Diagnosis in Children: Urging Caution.

OBJECTIVES: Several recent celiac disease guidelines recommend the acquisition of duodenal bulb biopsies for diagnostics. This is in conflict with previously reported evidence and routine practice from the 1960s onward. We reopened the issue in a prospective multicenter study and used morphometric variables in evaluating the usefulness of bulb biopsies in children. We further sought to establish whether deposits of IgA targeting bulb transglutaminase 2 (TG2) could be of diagnostic help. METHODS: Diagnoses of celiac disease were based on clinic and distal duodenal histopathology statements. Centralized reading of villous height (VH) to crypt depth (CrD) ratios and IgA deposits was performed on anatomical duodenal bulb specimens. All children participating also underwent routine investigations for other diseases. RESULTS: Twenty-two children had celiac disease, and another 22 served as non-celiac disease controls. The quality of the anatomical bulb specimens was unsatisfactory for reliable morphometric measurements in 20 out of 44 (45%) patients even after recuttings. All celiac disease patients had VH:CrD<2.0 (mean 0.2) but also 10 out of 13 (77%) non-celiac control patients had an injured bulb mucosal lining (mean 1.3) even up to false-positive "flat lesion". Bulb IgA deposits were able to separate celiac disease from disease controls. CONCLUSIONS: Morphological injury is common in the anatomical bulb even without celiac disease, increasing the risk of false-positive diagnoses. Premature conclusions might have been drawn on current care guidelines as to celiac disease diagnosis based solely on anatomical bulb specimens. Bulb mucosal IgA targeting TG2 in poor quality biopsy specimens is a powerful clinical tool in finding celiac disease patients.

Dermatitis Herpetiformis Refractory to Gluten-free Dietary Treatment.

Dermatitis herpetiformis (DH) is a blistering skin disease, which is regarded as an extra-intestinal manifestation of coeliac disease. Refractory cases of coeliac disease, that do not respond to a gluten-free diet and which carry an increased risk of lymphoma, are well-known in coeliac disease. To determine whether refractory cases of DH with active rash and persistent small bowel atrophy occur we analysed our series of 403 patients with DH. Seven (1.7%) patients, who had been on a gluten-free diet for a mean of 16 years, but who still required dapsone to treat the symptoms of DH, were identified. Of these, one patient died from mucinous adenocarcinoma before re-examination. At re-examination skin immunoglobulin A (IgA) deposits were found in 5/6 refractory and 3/16 control DH patients with good dietary response. Small bowel mucosa was studied at re-examination from 5 refractory and 8 control DH patients and was normal in all 5 refractory and 7/8 control DH patients. One refractory DH patient died from adenocarcinoma, but no lymphoma developed in any of the patients. This study documents for the first time refractory DH, in which the rash is non-responsive to a gluten-free diet, but the small bowel mucosa heals. This differs from refractory coeliac disease, in which the small bowel mucosa does not heal on a gluten-free diet.

Predictors and Significance of Incomplete Mucosal Recovery in Celiac Disease After 1 Year on a Gluten-Free Diet.

OBJECTIVES: In celiac disease, a follow-up biopsy taken 1 year after diagnosis is considered important in monitoring histological recovery. In many cases, recovery is incomplete, and the clinical significance of this is poorly understood. We now investigated associated factors and the significance of imperfect histological recovery in patients in whom the follow-up had been completed. METHODS: Two hundred sixty-three biopsy-proven patients were divided into two groups: histological recovery and incomplete recovery after 1 year on gluten-free diet. Serology, laboratory values, bone mineral density, and different clinical variables were measured at diagnosis and after 1 year. Gastrointestinal symptoms and quality of life were assessed by validated questionnaires. Further, long-term follow-up data on mortality, malignancies, and other severe complications were collected. RESULTS: The incomplete recovery group had more severe mucosal damage (P=0.003), higher antibody values (P=0.017), and more signs of malabsorption (P<0.001) at diagnosis. There was no difference in gender, symptoms or quality of life, family history of celiac disease, or comorbidities. At follow-up, there was still a difference in antibodies (P=0.018) and femoral T-scores (P=0.024). Histologically recovered patients showed better dietary adherence, although it was excellent in both groups (97% vs. 87%, P<0.001). There was no difference in long-term outcomes between groups. CONCLUSIONS: The presence of more severe disease in terms of histology, serology, and signs of malabsorption was associated with histological non-response. In patients with high dietary adherence, incomplete villous recovery after 1 year does not affect the clinical response or long-term prognosis. A personalized approach is required to decide the optimal timing of the follow-up biopsy.

Injection of celiac disease patient sera or immunoglobulins to mice reproduces a condition mimicking early developing celiac disease.

UNLABELLED: Typical features of celiac disease are small-bowel villus atrophy, crypt hyperplasia, and inflammation which develop gradually concomitant with ingestion of gluten. In addition, patients have anti-transglutaminase 2 (TG2) autoantibodies in their serum and tissues. The aim of this study was to establish whether celiac disease can be passively transferred to mice by serum or immunoglobulins. Serum aliquots or purified immunoglobulins (Ig) were intraperitoneally injected into Hsd:Athymic Nude-Foxn1nu mice for 8 or 27 days. As mice do not have proper IgA transport from peritoneum to blood, sera with a high content of IgG class anti-TG2 antibodies from untreated IgA-deficient celiac patients were used. Mouse sera were tested for celiac disease-specific autoantibodies, and several tissues were analyzed for autoantibody deposits targeted to TG2. Morphological assessment was made of the murine small intestinal mucosa. Injection of celiac disease patient sera or total IgG led to a significant delay in weight gain and mild diarrhea in a subset of mice. The mice injected with celiac patient sera or IgG had significantly decreased villus height crypt depth (Vh/CrD) ratios and celiac disease-specific autoantibody deposits targeted to TG2 in several tissues, including the small intestine. None of these features were observed in control mice. We conclude that administration of IgA-deficient celiac disease patient serum or total IgG induces both deterioration of the intestinal mucosa and clinical features of celiac disease in mice. The experimentally induced condition in the mice injected with patient serum or IgG resembles early developing celiac disease in humans. KEY MESSAGE: Celiac disease patient sera or total IgG was injected into athymic mice. A significant delay in weight gain and mild diarrhea was observed. Mice evinced significantly decreased villus height crypt depth ratios. Celiac disease-specific autoantibody deposits were present in several tissues. The condition in mice resembles early stage celiac disease in humans.