American College of Gastroenterology Guidelines Update: Diagnosis and Management of Celiac Disease

Yield of Gluten Challenge in Patients on Self-Prescribed Gluten-Free Diets

BACKGROUND

Patients on a gluten-free diet (GFD) whose celiac disease (CD) status is unknown may undergo gluten challenge (GC) to clarify their diagnosis. Though this is an established diagnostic practice, the proportion of patients undergoing GC who are diagnosed with CD is unknown.

AIMS

We aimed to analyze which factors were predictive of having CD in a cohort of patients who underwent GC followed by upper endoscopy with duodenal biopsy.

METHODS

We identified adult patients at a CD referral center who had been on a GFD and then underwent GC to determine a diagnosis of CD during the years spanning 2006 to 2020. We compared those patients found to have CD (defined as villus atrophy/Marsh 3) on duodenal biopsy with those who did not, using the chi square and Fischer exact tests.

RESULTS

We identified 206 patients who underwent GC. Of these 206, 30 (14%) were diagnosed with CD based on post-GC duodenal biopsy. 176 of the 206 (85%) patients reported various gastrointestinal symptoms, including bloating (39%), though these were more common in those without CD (any GI symptoms: 89% vs 67%, p 0.004; bloating: 43% vs 20%, p 0.019). Serology values, when normalized, including pre- and post-challenge TTG IgA (37% vs 1.7%, p 0.001; 23% versus 2.3%, p 0.001), DGP IgG and IgA (57% vs 2.8%, p 0.001; 37% vs 6.2%, p 0.001) were higher in the group of patients with CD.

CONCLUSION

Among patients undergoing GC for diagnostic purposes, only 14% had evidence of villus atrophy corresponding with CD on duodenal biopsy. The presence of any elevated pre-challenge serology was associated with CD. Bloating in combination with low serologies may help risk stratify patients as being less likely to have CD upon GC.

Autoimmunity-related LINC01934 and AP002954.4 lncRNA polymorphisms may be effective in pediatric celiac disease: a case-control study

OBJECTIVE

Various studies have reported that certain long non-coding RNA levels are unusually low in the intestines of celiac disease patients, suggesting that this may be associated with the inflammation observed in celiac disease. Despite these studies, the research aimed at uncovering the potential role of long non-coding RNAs in the pathogenesis of autoimmune diseases like celiac disease remains insufficient. Therefore, in this study, we plan to assess long non-coding RNA polymorphisms associated with autoimmunity in children diagnosed with celiac disease according to the European Society for Paediatric Gastroenterology Hepatology and Nutrition criteria.

METHODS

DNA was isolated from paraffin tissue samples of 88 pediatric celiac disease patients and 74 healthy pediatric individuals. Single-nucleotide polymorphism genotyping of five long non-coding RNA polymorphisms associated with autoimmunity (LINC01934-rs1018326, IL18RAP-rs917997, AP002954.4-rs10892258, UQCRC2P1-rs6441961, and HCG14 rs3135316) was conducted using the TaqMan single-nucleotide polymorphism genotyping assays with the LightCycler 480.

RESULTS

In our study, the genotypic and allelic frequency distribution of LINC01934-rs1018326 and AP002954.4-rs10892258 polymorphisms was found to be statistically significant in the comparison between the two groups (p<0.05). According to the multiple genetic model analyses, the LINC01934-rs1018326 polymorphism was observed to confer a 1.14-fold risk in the recessive model and a 1.2-fold risk in the additive model for pediatric celiac disease. Similarly, the AP002954.4-rs10892258 polymorphism was found to pose a 1.40-fold risk in the dominant model and a 1.7-fold risk in the additive model.

CONCLUSION

Our study results draw attention to the LINC01934-rs1018326 and AP002954.4-rs10892258 polymorphisms in celiac disease and suggest that these polymorphisms may be associated with inflammation in autoimmune diseases like celiac disease.

Did diet compliance and remission reduce oxidative stress in celiac patients?

OBJECTIVE

We aimed to examine the effect of remission status on thiol-disulfide homeostasis in celiac patients and thus to indirectly determine the effect of oxidative stress and inflammation caused by non-compliance with the diet.

METHODS

Between February 2019 and December 2021, 117 patients diagnosed with celiac disease were included in this prospective randomized and controlled study. In addition to routine tests of celiac patients, thiol and disulfide measurements were made from the blood both at the beginning of the study and at the end of the first year.

RESULTS

While 52 of the patients (44.4%) were in remission, 65 patients (55.6%) were not. There was an evident increase in native thiol levels of the patients who were initially not in remission but went into at the end of the first year (347.4±46.7 μmol/L vs. 365.3±44.0 μmol/L; p=0.001). Mean plasma disulfide levels of patients with celiac going into remission became reduced in the first year from the level of 14.5±5.1 μmol/L down to 8.9±4.2 μmol/L (p<0.001). In celiac patients who entered remission, disulfide and anti-tissue transglutaminase immunoglobulin A levels decreased in a correlation (r=0.526; p<0.001).

CONCLUSION

Not being in remission in celiac disease leads to increased oxidative stress, and thiol-disulfide homeostasis is an indirect indicator of this. Additionally, providing remission in celiac patients reduces oxidative stress.

Monitoring coeliac disease in 2024, time to change practice?

PURPOSE OF REVIEW

Persistent villous atrophy is associated with morbidity in coeliac disease and most commonly due to ongoing gluten ingestion. Current methods for assessing gluten exposure and persisting villous atrophy include dietary questionnaires and repeat duodenal biopsy, which have limited accuracy or are invasive. This review discusses adjunctive and/or novel tests that could be used to overcome these challenges.

RECENT FINDINGS

Small bowel capsule endoscopy is well tolerated and helps to evaluate for persisting villous atrophy and importantly, complications associated with coeliac disease. Testing for urinary and/or stool gluten immunogenic peptides may help identify recent gluten exposure, but further studies are still warranted to evaluate the accuracy and applicability of this approach. Measuring spikes in circulating Interleukin-2 following gluten challenge has shown promise for coeliac disease diagnosis, and thus may serve as a useful confirmatory test in those with persisting symptoms but provides no information on mucosal inflammation. No specific gut microbial signature has been identified in coeliac disease; however, studies have shown a reduced microbial diversity in active disease, which with future refinement may prove clinically useful.

SUMMARY

There is no evidence to support alternative methods for assessing persisting villous atrophy in coeliac disease over performing an up-to-date duodenal biopsy. Monitoring for adherence to a gluten-free diet remains clinically challenging and should be a priority for future research.

Long-Term Natural History of Autoimmune Gastritis: Results From a Prospective Monocentric Series

INTRODUCTION

The natural history of autoimmune gastritis (AIG) has been poorly described. In this study, we report the long-term natural history and clinical clustering of the full spectrum of AIG, from the potential to the complicated stage.

METHODS

Prospective single-center study conducted in a tertiary referral center. Patients with AIG at any stage (0 = potential; 1 = early; 2 = florid; 3 = severe; and 4 = complicated) were enrolled (January 2000-December 2022). The histopathological evolution, the clinical presentation, and the correlates of evolution of potential AIG were assessed.

RESULTS

Four hundred ninety-eight patients with AIG (mean age 56.7 ± 15.2 years, F:M ratio 2.5:1) were included, of whom 93 experienced potential AIG. The maximum disease duration was 27 years (median 18, interquartile range 14-23), while the overall median follow-up was 52 months (interquartile range 12-95). Age was significantly lower in stage 0 compared with that in the other stages. Accidental histologic evidence and hematologic findings were the most common clusters of diagnosis. The overall median rate of progression was 7.29 per 100 persons/yr (95% confidence interval [CI] 6.19-8.59), while the stage-specific rates of progression were 10.85 (stage 0; 95% CI 7.75-15.18), 14.83 (stages 1-2; 95% CI 11.89-18.49), and 2.68 (stage 3; 95% CI 1.88-3.84). Newly onset neoplastic complications at follow-up occurred in 41/483 patients (8.5%; 23 neuroendocrine tumors and 18 epithelial dysplasia). No cases of adenocarcinoma were noticed. Male sex was associated with a greater likelihood of evolving from potential AIG to overt AIG.

DISCUSSION

AIG is a progressive disorder, with a virtually absent risk of gastric adenocarcinoma. Patients with potential AIG should be monitored because they carry a high risk of evolving into overt AIG.

Prevalence and Predictors of Follow-up Endoscopic Biopsy in Patients With Celiac Disease in the United States

OBJECTIVE

To characterize the frequency and predictors of follow-up endoscopic biopsy in patients with celiac disease.

BACKGROUND

The utility of routine follow-up biopsy in patients after a diagnosis of celiac disease is uncertain, especially in patients whose symptoms resolve on the gluten-free diet.

PATIENTS AND METHODS

Using the Merative MarketScan U.S. commercial insurance and Medicare databases, we identified 30,737 patients with biopsy-diagnosed celiac disease. We followed them until they had a second duodenal biopsy (our primary outcome) or insurance coverage ended.

RESULTS

Among the patients with celiac disease we identified, 5976 (19.4%) underwent a follow-up biopsy. The median time between initial and follow-up biopsies was 16.8 months. Compared with younger patients, those aged 20 years or older had an increased likelihood of undergoing a follow-up biopsy (cumulative incidence rate at 5 y for patients age ≥20 y was 36.0%, 95% CI: 35.0%-37.1% vs 21.9%, 95% CI: 20.5%-23.4% in patients age ≤19 y). Follow-up biopsies occurred less frequently in more recent calendar years. Follow-up biopsy was more common among patients with an Elixhauser Comorbidity Index of 1 (hazard ratio: 1.09; 95% CI: 1.01-1.17) or ≥2 (hazard ratio: 1.28; 95% CI: 1.20-1.37) compared with patients with an index of zero. Among patients who had a follow-up biopsy, 57% had a celiac disease-related symptom recorded in the 30 days before the procedure.

CONCLUSIONS

Follow-up duodenal biopsy is performed in a substantial minority of U.S. patients with celiac disease. Adult age and increased comorbidity burden were associated with a greater likelihood of follow-up biopsy. Just under half of follow-up biopsies are performed for routine surveillance, in the absence of persistent symptoms.

Risk of Gluten Cross-Contamination Due to Food Handling Practices: A Mini-Review

Celiac disease (CD) is an autoimmune disease triggered by the ingestion of gluten in genetically predisposed individuals, affecting 1.4% of the world population. CD induces an inflammatory reaction that compromises small intestine villi, leading to nutrient malabsorption, and gastro and extraintestinal manifestations. Although other treatment approaches are being studied, adherence to a gluten-free diet (GFD) is the only effective intervention to date. Despite this, about 50% of patients experience persistent inflammation, often associated with unintentional gluten ingestion through contaminated food. There are regulations for labeling gluten-free foods which specify a limit of 20 mg/kg (20 ppm). The risks of gluten cross-contamination above that level are present throughout the whole food production chain, emphasizing the need for caution. This review explores studies that tested different procedures regarding the shared production of gluten-containing and gluten-free food, including the use of shared equipment and utensils. A literature review covering PubMed, Scielo, Web of Science, VHL and Scopus identified five relevant studies. The results indicate that shared environments and equipment may not significantly increase gluten cross-contamination if appropriate protocols are followed. Simultaneous cooking of gluten-containing and gluten-free pizzas in shared ovens has demonstrated a low risk of contamination. In general, shared kitchen utensils and equipment (spoon, ladle, colander, knife, fryer, toaster) in controlled experiments did not lead to significant contamination of samples. On the other hand, cooking gluten-free and gluten-containing pasta in shared water resulted in gluten levels above the established limit of 20 ppm. However, rinsing the pasta under running water for a few seconds was enough to reduce the gluten content of the samples to less than 20 ppm.

Path Towards Biopsy-Free Diagnosis of Celiac Disease in Pediatric Patients

BACKGROUND

Laboratory testing for celiac disease in pediatric patients integrates serology, genetic susceptibility and duodenal biopsy examination. The 2023 American College of Gastroenterology guidelines recommend a biopsy-free approach in pediatric patients utilizing tissue transglutaminase antibody titers >10 times upper limit of normal and subsequent endomysial antibody seropositivity as sufficient for diagnosis. The objective of this study is to assess the diagnostic accuracy of biopsy-free approach at our pediatric hospital.

METHODS

We conducted a retrospective study involving pediatric patients who underwent biopsy for diagnostic confirmation of celiac disease between May 2019 and May 2023. For these patients, the tissue transglutaminase and endomysial antibody test results were retrieved and performance of biopsy-free approach was assessed using the duodenal histology as the gold standard for celiac disease diagnosis.

RESULTS

Tissue transglutaminase antibody titers >10 times upper limit of normal alone demonstrated a positive predictive value of 99% for identifying celiac disease in children. Although endomysial antibody testing is underutilized at our center, its inclusion further improved the predictability to 100 %.

CONCLUSION

Positive predictive value of tissue transglutaminase antibody titers >10 times upper limit of normal is sufficiently high for celiac disease diagnosis in children and may allow for deferral of duodenal biopsy at diagnosis.

Celiac disease: Hope for new treatments beyond a gluten-free diet

BACKGROUND & AIMS

Celiac disease (CD) is a chronic inflammatory disease of the small intestine induced and maintained by gluten ingestion in susceptible individuals. Current treatment consists of strict adherence to a lifelong gluten-free diet (GFD) which is considered safe and effective in the large majority of patients. However, since adherence to a GFD is difficult and has a negative impact on quality of life, an increasing interest in other treatment options has emerged. Moreover, in some individuals a GFD is not sufficiently effective, necessitating alternative treatments.

METHODS

By performing a systematic search, we constructed a detailed narrative review. Only treatment options considered relevant and conducted in a phase I, II or III clinical trial were included.

RESULTS

Based on the pathophysiology of CD, four major therapeutic approaches can be distinguished: firstly, by focusing on intraluminal gluten detoxification before absorption occurs, secondly, by modulating intestinal permeability and preventing paracellular uptake, thirdly, by enhancing immunological tolerance to gluten and finally, by regulating gluten auto-immunity.

CONCLUSIONS

Despite significant efforts, no treatment has yet completed a phase III clinical trial. Future studies will likely focus on the use of supplemental drugs in conjunction to a GFD, with ALV003 and ZED-1227 currently being the most promising therapeutic options.

Efficacy of a Low-FODMAP Diet for Coeliac Patients with Persistent IBS-like Symptoms despite a Gluten-Free Diet: A Systematic Review

Background: Persistent symptoms in coeliac disease (CD) can be due to not only poor gluten-free diet (GFD) adherence and complications of CD, but also functional gastrointestinal disorders such as irritable bowel syndrome (IBS). Although the role of a low fermentable oligo-, di-, and monosaccharides and polyols (FODMAP) diet is well-established in IBS, little data are available on its role in coeliac patients with persistent IBS-like symptoms despite a GFD. Methods: We systematically reviewed the literature in accordance with the PRISMA guidelines for studies evaluating the role of FODMAPs and/or a low-FODMAP diet in coeliac patients with persistent symptoms. PubMed and Embase were searched from inception to 16 January 2024 for eligible full-text papers. The study protocol was registered on Open Science Framework. Results: A total of 239 records were identified, and six papers were included. Of these, four were interventional studies comparing a low-FODMAP GFD to a regular GFD for persistent symptoms in 115 total coeliac patients (two randomized controlled trials and two open-label studies). A low-FODMAP GFD for a minimum of 4 weeks was significantly more effective than a regular GFD in reducing symptoms (p < 0.05 in 3/4 studies). Dietary FODMAP content of a conventional GFD was significantly lower than that of non-coeliac patients on a gluten-containing diet (both p < 0.05), especially regarding high-FODMAP grain products. However, coeliac patients consumed more servings of fruits/vegetables high in FODMAP. No relationship between FODMAP intake and persistence of symptoms was reported. Conclusions: A low-FODMAP diet may be beneficial for uncomplicated celiac patients with persistent IBS-like symptoms despite strict adherence to a GFD.

Coeliac disease: the paradox of diagnosing a food hypersensitivity disorder with autoantibodies

Serum antibodies to the autoantigen transglutaminase 2 (TG2) are increasingly harnessed to diagnose coeliac disease. Diagnostic guidelines for children give recommendation for a no-biopsy-based diagnosis through detection of high amounts of IgA anti-TG2 antibodies in serum with confirmation of positivity in a separate blood sample by characteristic autoantibody-staining of tissue. While measurement of IgA anti-TG2 also is important in the diagnostic workup of adults, the adult guidelines still mandate examination of gut biopsies. This requirement might well change in the future, as might the necessity for confirming autoantibody positivity by tissue staining. The key role of autoantibody serology for diagnosis of coeliac disease is paradoxical. Coeliac disease was considered, and still can be considered, a food intolerance disorder where autoantibodies at face value are out of place. The immunological mechanisms underlying the formation of autoantibodies in response to gluten exposure have been dissected. This review presents the current insights demonstrating that the autoantibodies in coeliac disease are intimately integrated in the maladapted immune response to gluten.

CT and MR Enterography in the Evaluation of Celiac Disease

Celiac disease is a common inflammatory disease of the small bowel that induces mucosal intestinal lesions. The disease is mediated by an immune response and triggered by the ingestion of gluten in genetically predisposed individuals. Gluten contains gliadin, a component found mostly in wheat, barley, and rye. This process leads to gastrointestinal malabsorption with symptoms such as diarrhea, constipation, abdominal pain, and distention. It has a prevalence of 1%-2% in the general adult population, who present with symptoms at any age, but is more frequently found in adult women in the 3rd or 4th decade of life. Recognition of the disease has increased, but it remains a challenge to diagnose. CT and MR enterography are noninvasive studies used for evaluation of small bowel neoplasms and inflammatory small bowel pathologic conditions such as celiac disease. The authors review the spectrum of intestinal and extraintestinal findings of celiac disease at CT and MR enterography, as well as its complications, and the importance of recognizing certain imaging features that help in the diagnosis of celiac disease. More common and specific findings of celiac disease such as inversion of the jejunoileal fold pattern and mesenteric lymphadenopathy are reviewed. More uncommon entities that are more frequently associated with refractory or untreated celiac disease, such as ulcerative jejunoileitis, cavitary mesenteric lymph node syndrome, and malignancies including small bowel adenocarcinoma and lymphoma, are described. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. The slide presentation from the RSNA Annual Meeting is available for this article.

Accuracy of the No-Biopsy Approach for the Diagnosis of Celiac Disease in Adults: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Current international guidelines recommend duodenal biopsies to confirm the diagnosis of celiac disease in adult patients. However, growing evidence suggests that immunoglobulin A (IgA) anti-tissue transglutaminase (tTg) antibody levels ≥10 times the upper limit of normal (ULN) can accurately predict celiac disease, eliminating the need for biopsy. We performed a systematic review and meta-analysis to evaluate the accuracy of the no-biopsy approach to confirm the diagnosis of celiac disease in adults.

METHODS

We systematically searched MEDLINE, EMBASE, Cochrane Library, and Web of Science from January 1998 to October 2023 for studies reporting the sensitivity and specificity of IgA-tTG ≥10×ULN against duodenal biopsies (Marsh grade ≥2) in adults with suspected celiac disease. We used a bivariate random effects model to calculate the summary estimates of sensitivity, specificity, and positive and negative likelihood ratios. The positive and negative likelihood ratios were used to calculate the positive predictive value of the no-biopsy approach across different pretest probabilities of celiac disease. The methodological quality of the included studies was evaluated using the QUADAS-2 tool. This study was registered with PROSPERO, number CRD42023398812.

RESULTS

A total of 18 studies comprising 12,103 participants from 15 countries were included. The pooled prevalence of biopsy-proven celiac disease in the included studies was 62% (95% confidence interval [CI], 40%-83%). The proportion of patients with IgA-tTG ≥10×ULN was 32% (95% CI, 24%-40%). The summary sensitivity of IgA-tTG ≥10×ULN was 51% (95% CI, 42%-60%), and the summary specificity was 100% (95% CI, 98%-100%). The area under the summary receiver operating characteristic curve was 0.83 (95% CI, 0.77 - 0.89). The positive predictive value of the no-biopsy approach to identify patients with celiac disease was 65%, 88%, 95%, and 99% if celiac disease prevalence was 1%, 4%, 10%, and 40%, respectively. Between-study heterogeneity was moderate (I2 =30.3%), and additional sensitivity analyses did not significantly alter our findings. Only 1 study had a low risk of bias across all domains.

CONCLUSION

The results of this meta-analysis suggest that selected adult patients with IgA-tTG ≥10×ULN and a moderate to high pretest probability of celiac disease could be diagnosed without undergoing invasive endoscopy and duodenal biopsy.

Gluten-related Disorders From Bench to Bedside

Celiac disease, non-celiac gluten sensitivity, and wheat allergy comprise 3 of the main conditions with wheat- and gluten-containing foods as the symptom trigger. Distinguishing between these entities can be daunting. In this review, we compare and contrast celiac disease, non-celiac gluten sensitivity, and wheat allergy to allow clinicians to determine which diagnosis fits their patient to facilitate high-quality management and longitudinal care.

A Dedicated Celiac Disease Program Improves Celiac Quality Care Metrics and Short-Term Outcomes in Real Life

BACKGROUND AND AIMS

Dedicated multidisciplinary programs in gastroenterology are emerging with the goal to improve care. There is little information about the effects of a celiac disease program on disease-related quality care metrics and outcomes. We aimed to compare quality care metrics, symptom resolution, and serological response among patients diagnosed and treated in a celiac disease program with a standard of care cohort.

METHODS

We performed a retrospective cohort study with adult celiac disease patients. We divided patients into two groups: celiac disease patients treated in our program and those treated by gastroenterologists not affiliated with the program (standard of care). We abstracted data from electronical medical records and compared frequency at which guideline-driven quality care metrics were obtained, assessed symptom resolution, and serological response based on IgA anti-tissue transglutaminase levels.

RESULTS

We included 340 patients, 120 in the celiac disease program (89 women) and 220 (166 women) in the standard of care. Frequency of quality care metrics implementation in program patients was significantly greater for all variables (p < 0.0005). Diarrhea resolved in 38/46 (82.6%) in the CD program and 63/98 (64.2%) in the standard of care after starting a gluten-free diet (p = .025); bloating also resolved significantly more often in the former (26/34) than the latter (31/58; p = 0.03). Otherwise, there were no significant differences in resolution of clinical symptoms or serological response.

CONCLUSION

A celiac disease program improves celiac-related quality care metrics and may improve outcomes such as diarrhea resolution compared to standard of care.

Monitoring patients with celiac disease on gluten free diet: different outcomes comparing three tissue transglutaminase IgA assays

OBJECTIVES

Tissue transglutaminase (tTG) IgA antibodies are a hallmark for celiac disease (CD). In CD patients on gluten free diet (GFD) these antibodies are transient. Few studies are available comparing the tTG-IgA assay characteristics for monitoring response to GFD. Since discrepant results were reported in patients on GFD after switching tTG-IgA assays, we conducted a retrospective observational study to monitor GFD response using three different tTG-IgA assays.

METHODS

Diagnostic samples from 44 adults and 17 children with CD were included. Of most patients two follow-up samples after introduction of GFD were available. In all samples tTG-IgA were assessed using one fluorochrome-enzyme immuno-assay (FEIA) and two chemiluminescence immuno-assays (CLIA) and intestinal fatty acid binding protein (i-FABP) as surrogate marker for intestinal epithelial damage was measured.

RESULTS

Using CLIA assays, normalization of antibody levels was delayed compared to FEIA (p<0.001). Of all samples taken after at least 6 months on GFD with elevated i-FABP indicating intestinal epithelial damage, 40 % had positive tTG-IgA according to the FEIA, 85 and 90 % according to the two CLIA.

CONCLUSIONS

Normalization of tTG-IgA in patients on GFD depends on the assay used. Both CLIA appear to be more sensitive in detecting suboptimal treatment response in CD-indicated by elevated i-FABP - when applying the manufacturer's recommended cut-off for the diagnosis of CD.

Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet

BACKGROUND

The gluten-free diet (GFD) has limitations, and there is intense research in the development of adjuvant therapies.

AIM

To examine the effects of orally administered Aspergillus niger prolyl endopeptidase protease (AN-PEP) on inadvertent gluten exposure and symptom prevention in adult celiac disease (CeD) patients following their usual GFD.

METHODS

This was an exploratory, double-blind, randomized, placebo-controlled trial that enrolled CeD patients on a long-term GFD. After a 4-wk run-in period, patients were randomized to 4 wk of two AN-PEP capsules (GliadinX; AVI Research, LLC, United States) at each of three meals per day or placebo. Outcome endpoints were: (1) Average weekly stool gluten immunogenic peptides (GIP) between the run-in and end of treatments and between AN-PEP and placebo; (2) celiac symptom index (CSI); (3) CeD-specific serology; and (4) quality of life. Stool samples were collected for GIP testing by ELISA every Tuesday and Friday during run-ins and treatments.

RESULTS

Forty patients were randomized for the intention-to-treat analysis, and three were excluded from the per-protocol assessment. Overall, 628/640 (98.1%) stool samples were collected. GIP was undetectable (< 0.08 μg/g) in 65.6% of samples, and no differences between treatment arms were detected. Only 0.5% of samples had GIP concentrations sufficiently high (> 0.32 μg/g) to potentially cause mucosal damage. Median GIP concentration in the AN-PEP arm was 44.7% lower than in the run-in period. One-third of patients exhibiting GIP > 0.08 μg/g during run-in had lower or undetectable GIP after AN-PEP treatment. Compared with the run- in period, the proportion of symptomatic patients (CSI > 38) in the AN-PEP arm was significantly lower (P < 0.03). AN-PEP did not result in changes in specific serologies.

CONCLUSION

This exploratory study conducted in a real-life setting revealed high adherence to the GFD. The AN-PEP treatment did not significantly reduce the overall GIP stool concentration. However, given the observation of a significantly lower prevalence of patients with severe symptoms in the AN-PEP arm, further clinical research is warranted.

New entity of adult ultra-short coeliac disease: the first international cohort and case-control study

BACKGROUND

Ultra-short coeliac disease (USCD) is defined as villous atrophy only present in the duodenal bulb (D1) with concurrent positive coeliac serology. We present the first, multicentre, international study of patients with USCD.

METHODS

Patients with USCD were identified from 10 tertiary hospitals (6 from Europe, 2 from Asia, 1 from North America and 1 from Australasia) and compared with age-matched and sex-matched patients with conventional coeliac disease.

FINDINGS

Patients with USCD (n=137, median age 27 years, IQR 21-43 years; 73% female) were younger than those with conventional coeliac disease (27 vs 38 years, respectively, p<0.001). Immunoglobulin A-tissue transglutaminase (IgA-tTG) titres at index gastroscopy were lower in patients with USCD versus conventional coeliac disease (1.8×upper limit of normal (ULN) (IQR 1.1-5.9) vs 12.6×ULN (IQR 3.3-18.3), p<0.001).Patients with USCD had the same number of symptoms overall (median 3 (IQR 2-4) vs 3 (IQR 1-4), p=0.875). Patients with USCD experienced less iron deficiency (41.8% vs 22.4%, p=0.006).Both USCD and conventional coeliac disease had the same intraepithelial lymphocytes immunophenotype staining pattern; positive for CD3 and CD8, but not CD4.At follow-up having commenced a gluten-free diet (GFD) (median of 1181 days IQR: 440-2160 days) both USCD and the age-matched and sex-matched controls experienced a similar reduction in IgA-tTG titres (0.5 ULN (IQR 0.2-1.4) vs 0.7 ULN (IQR 0.2-2.6), p=0.312). 95.7% of patients with USCD reported a clinical improvement in their symptoms.

INTERPRETATION

Patients with USCD are younger, have a similar symptomatic burden and benefit from a GFD. This study endorses the recommendation of D1 sampling as part of the endoscopic coeliac disease diagnostic workup.

Gluten-free diet adherence in pediatric celiac patients: Evaluating CDAT questionnaire and test for gluten detection in urine

OBJECTIVES

This study aimed to evaluate the contributions of the Adapted Celiac Dietary Adherence Test (CDAT) and the Rapid Urinary Gluten Detection Test (u-GIP) in assessing gluten-free diet adherence in children and adolescents with celiac disease.

METHODS

Fifty-four celiac patients from two pediatric gastroenterology outpatient clinics affiliated with university hospitals were evaluated. The original CDAT was adapted for children through a transcultural process, and the original cutoff point was adopted to define adherence. A single examiner carried out the u-GIP test in fresh urine samples. Sociodemographic and clinical factors and family food security status were also evaluated.

RESULTS

A total of 88.9% of participants (confidence interval [CI]: 77.4-95.8; p<0.001) adhered to the gluten-free diet, as determined by the adapted CDAT score, while 87.0% (CI: 75.1-94.6; p<0.001) had negative u-GIP results. Among the 48 children adhering to the CDAT, six exhibited positive u-GIP results in a urine sample. Of the six nonadherent participants, only one had a positive u-GIP result. Notably, none of the children and adolescents with celiac disease who tested positive for u-GIP reported symptoms on the day of testing, and their growth rates remained stable.

CONCLUSIONS

Even celiac children and adolescents adhering to the CDAT questionnaire may show a positive u-GIP in a single measurement without accompanying symptoms or growth impairment. The u-GIP could be helpful in complementary tests in specific situations, such as for patients who exhibit compliant behavior but still experience symptoms or maintain persistent positive serology.

Celiac Disease-Related Conditions: Who to Test?

Celiac disease (CeD) is a chronic immune-mediated condition triggered by gluten consumption in genetically predisposed individuals. Approximately 1% of the general population is affected by the disorder. Disease presentation is heterogeneous and, despite growing awareness among physicians and the public, it continues to be underestimated. The most effective strategy for identifying undiagnosed CeD is proactive case finding through serologic testing in high-risk groups. We reviewed the most recent evidence on the association between CeD and more than 20 conditions. In light of this review, CeD screening is recommended in individuals with (1) autoimmune disease and accompanying symptoms suggestive of CeD; (2) diseases that may mimic CeD (eg, irritable bowel syndrome [IBS], inflammatory bowel disease [IBD], and microscopic colitis); and (3) among patients with conditions with a high CeD prevalence: first-degree relatives, idiopathic pancreatitis, unexplained liver enzyme abnormalities, autoimmune hepatitis, primary biliary cholangitis, hyposplenism or functional asplenia with severe bacterial infection, type 1 diabetes mellitus, Hashimoto's thyroiditis and Graves' disease, Sjögren's syndrome, dermatitis herpetiformis, recurrent aphthous syndrome and enamel defects, unexplained ataxia, peripheral neuropathy, delayed menarche or premature menopause, Down syndrome, Turner syndrome, Williams syndrome, chronic fatigue syndrome, IgA nephropathy, and IgA deficiency. CeD serology should be the initial step in the screening process. However, for patients with any of the aforementioned disorders who are undergoing upper endoscopy, biopsies should be performed to rule out CeD.

Status of vitamins and minerals in children with screening-identified celiac disease: A case-control study

OBJECTIVES

Micronutrient deficiencies characterize classical "late-diagnosed" celiac disease (CeD). This study aimed to identify the prevalence of micronutrient deficiencies among children with "early-diagnosed" screening-identified CeD to determine the clinical value of routine testing for deficiencies in those patients.

METHODS

A case-control study was conducted on screening-identified CeD patients diagnosed during a mass screening study (84 patients, mean age 11.3 ± 2.6 years). The controls (443 children, mean age 10.8 ± 2.5 years) were negative for celiac disease serological screening. Hemoglobin, serum levels of iron, ferritin, folate, vitamin B12, vitamin A, vitamin E, 25-OH vitamin D, zinc, and selenium were measured.

RESULTS

The mean serum levels of hemoglobin, iron, ferritin, vitamin D, zinc, copper, and selenium were significantly lower in CeD patients than in healthy controls (hemoglobin 12.56 vs. 13.02 g/dL [p = 0.04]; iron 10.61 vs. 17.6 µmol/L [p < 0.001], ferritin 25.7 vs. 48.3 µg/L [p < 0.001], vitamin D 29.1 vs. 37.5 nmol/L, zinc 11.9 vs. 21.7 µmol/L, copper 18.9 vs. 32.5 µmol/L, selenium 1.04 vs. 1.36 µmol/L; p < 0.001). Patients with celiac and severe intestinal damage (Marsh IIIb and IIIc) had significantly lower serum ferritin and vitamin A levels than patients with mild intestinal damage (Marsh II and IIIa) (ferritin 15 vs. 22 µg/L, p < 0.025; vitamin A 0.85 vs. 1.35 µmol/L, p = 0.007).

CONCLUSION

Micronutrient deficiencies are still detectable in "early-diagnosed" screening-identified CeD cases, a clinically relevant result that strongly supports efforts for screening and early diagnosis of CeD.

Fulminant Celiac Disease Presenting in the Postpartum Period

Celiac disease (CD) is an immune-mediated disorder of the small intestine triggered by dietary exposure to gluten in genetically susceptible individuals. Adult CD usually has an insidious onset with gastrointestinal symptoms, most often diarrhea and weight loss. The association between CD and reproductive abnormalities has been well described in the literature, but it is uncommon for CD to initially manifest during pregnancy or the postpartum period. We report a case of adult CD in a previously healthy woman with a life-threatening presentation during the postpartum period.

Prevalence of coeliac disease in patients with systemic lupus erythematosus: a systematic review and meta-analysis

BACKGROUND

There is some evidence of a higher prevalence of coeliac disease (CD) among patients with SLE than in the general population. However, the prevalence estimates vary substantially.

OBJECTIVE

To investigate the prevalence of CD among patients with SLE through systematic review and meta-analysis.

METHODS

We performed searches in the databases of Medline, Embase, Cochrane and Web of Science Core Collection between 1 January 1990 and 9 July 2023. A total of 2053 publications were rendered in the searches, of which 68 were reviewed in full text and 14 included in the analyses. Primary analysis estimated the pooled prevalence of biopsy-verified CD in patients with SLE. In the secondary analysis, the prevalence of serological markers indicative of CD was investigated. The quality of studies was appraised using the Joanna Briggs Institute Critical Appraisal Tool. We conducted meta-regression analyses to investigate associations between the prevalence of CD in individuals with SLE and publication year, study population size, CD prevalence in the general population, proportion of females and quality assessment score.

RESULTS

A total of 14 studies met the inclusion criteria, of which 11 were included in the primary analysis of biopsy-verified CD. Among 1238 patients with SLE, 14 had CD. The weighted pooled prevalence of CD was 0.7% (95% CI 0.0 to 1.8). The weighted pooled prevalence of CD serological markers in 1063 patients with SLE was 3.7% (95% CI 1.4 to 6.7). In meta-regression analyses, no associations between CD prevalence and study characteristics, demographics and quality assessment scores were found.

CONCLUSIONS

In this meta-analysis, we found a weighted pooled prevalence of biopsy-verified CD in patients with SLE comparable with the prevalence in the general population. Our findings do not support routine screening for CD in patients with SLE. However, individual screening could be considered in cases of clinical suspicion and additional risk factors for CD.

PROSPERO REGISTRATION NUMBER

CRD42022339594.

Clinical Data Do Not Reliably Predict Duodenal Histology at Follow-up in Celiac Disease: A 13 Center Correlative Study

Validated nonbiopsy methods to assure duodenal mucosal healing in celiac disease are lacking, yet ongoing mucosal injury is associated with anemia, osteoporosis, and lymphoma. Most providers utilize clinical data as surrogates of mucosal status to avoid additional esophagogastroduodenoscopy. The reliability of such surrogates to predict mucosal recovery has been incompletely evaluated. The aim of this study was to rigorously assess patterns of histologic mucosal recovery at follow-up in celiac disease and to correlate findings with clinical data. Gastrointestinal pathologists from 13 centers evaluated initial and follow-up duodenal biopsies from 181 celiac disease patients. Marsh scores and intraepithelial lymphocytes (IELs)/100 enterocytes were assessed blindly. Histology at follow-up was correlated with symptoms, immunoglobulin A anti-tissue transglutaminase titers and gluten-free diet adherence. Fifty-six/181 (31%) patients had persistent villous blunting and 46/181 (25%) patients had just persistently elevated IELs at follow-up, with only 79/181 (44%) patients having complete histologic remission. IEL normalization (82/181; 45%) lagged villous recovery (125/181;69%). In a minority of patients, villous blunting was limited to proximal duodenal biopsies. No correlation was found between Marsh scores and symptoms, normalization of immunoglobulin A anti-tissue transglutaminase serology, or diet adherence. Children showed greater recovery of Marsh score ( P <0.001) and IELs ( P <0.01) than adults. Persistent mucosal injury is common in celiac disease, with discordant villous/IEL normalization. Pathologist awareness of expected findings in celiac disease follow-up biopsies, including their frequent lack of correlation with clinical data, is important for patient management, and has implications for eligibility criteria for therapeutics currently in development.

Older age of celiac disease diagnosis and risk of autoimmune disease: A nationwide matched case-control study

OBJECTIVES

Celiac disease (CeD) has been linked to an increased risk of other autoimmune diseases, yet the impact of delayed CeD diagnosis on risk of developing additional autoimmune diseases remains uncertain. We investigated this through a nationwide matched case-control study.

METHODS

Using the ESPRESSO cohort with histophatology data from Sweden's 28 pathology departments, we assessed 46,575 biopsy-confirmed CeD cases from 1964 to 2017. We extracted 225,295 matched controls without histopathology information from the Swedish Total Population Register. Autoimmune disease was defined through diagnostic codes in the National Patient Register. Through conditional logistic regression we estimated odds ratio (OR) of autoimmune disease up until CeD diagnosis/matching date comparing CeD cases to controls across different age strata.

RESULTS

A total of 3059 (6.6 %) CeD patients and 4076 (1.8 %) controls had earlier autoimmune disease. The overall OR for autoimmune disease in CeD was 3.50 (95%CI 3.32-3.70). The risk of autoimmune disease did not escalate with increasing age at CeD diagnosis. Compared with controls, the OR of autoimmune disease in CeD patients was 7.70 (95%CI 4.71-12.57) in those diagnosed with CeD in 0-4 years, 19.02 (95%CI 13.80-26.23) in 5-9 years, 6.18 (95%CI 5.14-7.44) in 10-14 years, 4.80 (95%CI 3.97-5.79) in 15-19 years, 4.24 (95%CI 3.55-5.07) in 20-29 years, 4.65 (95%CI 3.93-5.51) in 30-39 years, 3.67 (95%CI 3.30-4.09) in 40-59 years, and 1.67 (95%CI 1.50-1.85) in ≥60 years.

CONCLUSIONS

This study revealed an increased risk of autoimmune disease among CeD patients compared with controls. However, older age at CeD diagnosis did not seem to escalate the risk of autoimmune diseases.

Patient and Community Health Global Burden in a World With More Celiac Disease

Celiac disease is one of the most common life-long disorders worldwide, with a prevalence mostly ranging between 0.7% and 2.9% in the general population and a higher frequency in females and well-defined at-risk groups, such as relatives of affected individuals and patients with autoimmune comorbidities. Increasing clinical detection is facilitated by improving awareness, implementation of a case-finding approach, and serology availability for screening at-risk patients, among other factors. Nevertheless, due to huge clinical variability, many celiac disease cases still escape diagnosis in most countries, unless actively searched by proactive policies. The burden of celiac disease is increasing, as is the need for better longitudinal care. Pediatric screening of the general population could represent the road ahead for an efficient intervention of secondary prevention aimed to reduce the social and health burden of celiac disease. This review analyses the epidemiology of celiac disease continent by continent, discusses current strategies to improve the detection of celiac disease, and highlights challenges related to the burden of celiac disease globally.

Opportunities for Improving Biopsy and Non-Biopsy-Based Diagnosis of Celiac Disease

The accumulating data regarding a non-biopsy diagnosis of celiac disease has led to its adoption in certain scenarios, although debate on whether and when to use non-biopsy criteria in clinical practice is ongoing. Despite the growing popularity and evidence basis for a biopsy-free approach to diagnosis in the context of highly elevated serologies, there will continue to be a role for a biopsy in some groups. This review summarizes the current evidence supporting a non-biopsy approach and arguments supporting continued reliance on biopsy, and focuses on opportunities to improve both approaches.

Celiac Disease Affects 1% of Global Population-Who Will Manage All These Patients? What Are Criteria to Prioritize Along Risk for Complications?

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.

Diagnosis of Seronegative and Ultrashort Celiac Disease

In its conventional form, celiac disease (CeD) is characterized by both positive serology and flat villi in the duodenum, and is well known by gastroenterologists and general practitioners. The aim of this review was to shed light on 2 neglected and not yet well-defined celiac phenotypes, that is, seronegative and ultrashort CeD. Seronegative CeD can be suspected in the presence of flat villi, positive HLA-DQ2 and/or HLA-DQ8, and the absence of CeD antibodies. After ruling out other seronegative enteropathies, the diagnosis can be confirmed by both clinical and histologic improvements after 1 year of a gluten-free diet. Ultrashort CeD is characterized by the finding of flat villi in the duodenal bulb in the absence of mucosal damage in the distal duodenum and with serologic positivity. Data on the prevalence, clinical manifestations, histologic lesions, genetic features, and outcome of seronegative and ultrashort CeD are inconclusive due to the few studies available and the small number of patients diagnosed. Some additional diagnostic tools have been developed recently, such as assessing intestinal transglutaminase 2 deposits, flow cytometry technique, microRNA detection, or proteomic analysis, and they seem to be useful in the identification of complex cases. Further cooperative studies are highly desirable to improve the knowledge of these 2 still-obscure variants of CeD.

Food Intolerances, Food Allergies and IBS: Lights and Shadows

This narrative review delves into the intricate relationship between irritable bowel syndrome (IBS) and food intolerances. IBS, a chronic functional gastrointestinal disorder, is characterized by symptoms like abdominal pain and altered bowel habits. The prevalence of IBS has increased globally, especially among young adults. Food and dietary habits play a crucial role in IBS management. About 85-90% of IBS patients report symptom exacerbation linked to specific food consumption, highlighting the strong connection between food intolerances and IBS. Food intolerances often exhibit a dose-dependent pattern, posing a challenge in identifying trigger foods. This issue is further complicated by the complex nature of gastrointestinal physiology and varying food compositions. This review discusses various dietary patterns and their impact on IBS, including the low-FODMAP diet, gluten-free diet, and Mediterranean diet. It highlights the importance of a personalized approach in dietary management, considering individual symptom variability and dietary history. In conclusion, this review emphasizes the need for accurate diagnosis and holistic management of IBS, considering the complex interplay between dietary factors and gastrointestinal pathophysiology. It underlines the importance of patient education and adherence to treatment plans, acknowledging the challenges posed by the variability in dietary triggers and the psychological impact of dietary restrictions.

Fracture risk among children and adolescents with celiac disease: a nationwide cohort study

BACKGROUND

Metabolic bone disease is a common manifestation of celiac disease (CD). We aimed to assess fracture risk among children and adolescents with CD compared with a matched group.

METHODS

This registry-based cohort study included 2372 children with CD who were matched 1:5 to 11,860 children without CD. Demographic and clinical data were obtained from the electronic database of Meuhedet, a health maintenance organization. Fracture events at ages 1-18 years were identified by coded diagnoses.

RESULTS

The overall fracture incidence rate was 256 per 10,000 patient-years (PY) in the CD group and 165 per 10,000 PY in the comparison group (p < 0.001). The hazard ratio (HR) to have a fracture was 1.57 (95% CI 1.43-1.73, p < 0.001) for the CD group compared to the matched group. The HR for multiple fractures was 1.67 (95% CI 1.38-2.01, p < 0.001). Analysis of the pre- and post-diagnosis periods separately showed that the HR for fractures in the pre-diagnosis period was 1.64 (95% CI 1.42-1.88, p < 0.001) for the CD group compared to the matched group, and 1.52 (95% CI 1.26-1.71, p < 0.001) in the period from diagnosis to the end of the follow-up period.

CONCLUSIONS

Children with CD had increased fracture risk both preceding and following the diagnosis of CD.

IMPACT

One manifestation of celiac disease (CD) is metabolic bone disease, including osteoporosis and impaired bone mineralization. We found increased fracture risk among children with CD, both preceding the CD diagnosis and during the years following the diagnosis. Recognition of the high risk of fractures in this population may help promote prevention. Further studies are needed to evaluate changes in bone quantity and quality after initiation of a gluten-free diet, and to identify those at risk for persistent metabolic bone disease.

Standardizing Randomized Controlled Trials in Celiac Disease: An International Multidisciplinary Appropriateness Study

BACKGROUND & AIMS

There is a need to develop safe and effective pharmacologic options for the treatment of celiac disease (CeD); however, consensus on the appropriate design and configuration of randomized controlled trials (RCTs) in this population is lacking.

METHODS

A 2-round modified Research and Development/University of California Los Angeles Appropriateness Method study was conducted. Eighteen gastroenterologists (adult and pediatric) and gastrointestinal pathologists voted on statements pertaining to the configuration of CeD RCTs, inclusion and exclusion criteria, gluten challenge, and trial outcomes. Two RCT designs were considered, representing the following distinct clinical scenarios for which pharmacotherapy may be used: trials incorporating a gluten challenge to simulate exposure; and trials evaluating reversal of histologic changes, despite attempted adherence to a gluten-free diet. Each statement was rated as appropriate, uncertain, or inappropriate, using a 9-point Likert scale.

RESULTS

For trials evaluating prevention of relapse after gluten challenge, participants adherent to a gluten-free diet for 12 months or more with normal or near-normal-sized villi should be enrolled. Gluten challenge should be FODMAPS (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) free, and efficacy evaluated using histology with a secondary patient-reported outcome measure. For trials evaluating reversal of villus atrophy, the panel voted it appropriate to enroll participants with a baseline villus height to crypt depth ratio ≤2 and measure efficacy using a primary histologic end point. Guidance for measuring histologic, endoscopic, and patient-reported outcomes in adult and pediatric patients with CeD are provided, along with recommendations regarding the merits and limitations of different end points.

CONCLUSIONS

We developed standardized recommendations for clinical trial design, eligibility criteria, outcome measures, gluten challenge, and disease evaluations for RCTs in patients with CeD.

Getting the BS out of Irritable Bowel Syndrome with Diarrhea (IBS-D): Let's Make a Diagnosis

PURPOSE OF REVIEW

Irritable bowel syndrome with diarrhea (IBS-D) is diagnosed when chronic symptoms of abdominal pain accompany loose stools, and alarm features, such as fever, anemia, rectal bleeding, and weight loss are absent. This combination of symptoms makes structural disorders, such as inflammatory bowel disease or cancer, unlikely, but does not exclude other conditions that cause these symptoms. The question is whether making a "positive diagnosis" of IBS-D based on symptoms alone and instituting therapy based on that diagnosis still makes sense.

RECENT FINDINGS

Clinical observations suggest that at least two-thirds of cases of IBS-D can be explained by three mechanisms: a) food intolerances (~ 30-40%), b) bile acid diarrhea (~ 20-30%), and c) disturbed microbial flora (~ 15-20%). Other conditions that are less frequent but can cause IBS symptoms or be confused with IBS include: celiac disease, microscopic colitis, mastocytosis/mast cell activation, and drug side-effects. Many cases of IBS-D have a discoverable, underlying cause that can direct therapy more efficiently.

Cutaneous Disorders Masking Celiac Disease: Case Report and Mini Review with Proposal for a Practical Clinical Approach

Celiac disease (CD) is an immune-mediated systemic gluten-related disorder characterized by a wide spectrum of intestinal and extra-intestinal manifestations, including damage to cutaneous and connective tissue. We report a rare case of chronic severe dermatitis involving connective tissue and cutaneous vascular vessels as the main clinical presentation of undiagnosed seronegative gluten disorder. A gluten-free diet dramatically improved the intestinal and cutaneous clinical damage in the patient. Pitfalls and the steps of differential diagnosis are described. We also review the literature regarding studies of CD and connective tissue diseases to extend the knowledge of these rare associations. We propose a practical diagnostic approach in suspected CD in autoimmune cutaneous disorders.

The Role of NKG2D and Its Ligands in Autoimmune Diseases: New Targets for Immunotherapy

Natural killer (NK) cells and CD8+ T cells can clear infected and transformed cells and generate tolerance to themselves, which also prevents autoimmune diseases. Natural killer group 2 member D (NKG2D) is an important activating immune receptor that is expressed on NK cells, CD8+ T cells, γδ T cells, and a very small percentage of CD4+ T cells. In contrast, the NKG2D ligand (NKG2D-L) is generally not expressed on normal cells but is overexpressed under stress. Thus, the inappropriate expression of NKG2D-L leads to the activation of self-reactive effector cells, which can trigger or exacerbate autoimmunity. In this review, we discuss the role of NKG2D and NKG2D-L in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), type I diabetes (T1DM), inflammatory bowel disease (IBD), and celiac disease (CeD). The data suggest that NKG2D and NKG2D-L play a pathogenic role in some autoimmune diseases. Therefore, the development of strategies to block the interaction of NKG2D and NKG2D-L may have therapeutic effects in some autoimmune diseases.

The Correlation Between Serum Anti-tissue Transglutaminase (Anti-tTG) Antibody Levels and Histological Severity of Celiac Disease in Adolescents and Adults: A Meta-Analysis

Celiac disease is an autoimmune disorder characterized by a broad spectrum of histological damage to the intestinal mucosa. Comprehension and understanding of the association between anti-tissue transglutaminase (anti-tTG) antibody levels and the histological severity of celiac disease are not well established, prompting the need for meta-analysis. This study aims to offer insights into the diagnostic abilities of anti-tTG antibody levels in determining the histological severity of celiac disease by providing quantitative evidence based on a diverse range of studies. An extensive search was conducted across four electronic research databases to identify primary research articles reporting serum anti-tTG antibody levels in correlation with different Marsh grades, signifying the histological severity of celiac disease. The software tool RevMan 5.4 (the Cochrane Collaboration, London, UK) was used to compile standardized mean differences (SMD) alongside their respective confidence intervals. A total of 13 studies were included in the meta-analysis, with a patient pool of 2505 patients. Marsh grade I and II were found to have higher anti-tTG antibody levels compared to those with grade 0 (SMD 1.50; 95% CI: 1.12, 1.87; p-value <0.00001). Antibody levels were higher in Marsh grade IIIa when compared to both grade 0 (SMD 0.97; 95% CI: 0.67, 1.28; p-value <0.00001) and grade ≤2 (SMD 0.61; 95% CI: 0.44, 0.79; p-value <0.00001). Patients with Marsh IIIb also reported greater anti-tTG levels compared to grade 0 (SMD 1.48; 95% CI: 0.99, 1.96; p-value <0.00001) and grade ≤2 (SMD 0.98; 95% CI: 0.79, 1.18; p-value <0.00001). Likewise, Marsh grade ≥IIIc reported high levels of anti-tTG antibodies in comparison with grade 0 (SMD 1.06; 95% CI: 0.72, 1.39; p-value <0.00001) and grade ≤2 (SMD 1.18; 95% CI: 1.02, 1.34; p-value <0.00001). Our meta-analysis revealed a consistent, robust correlation between anti-tTG antibody levels and the histological severity of celiac disease, with a clear trend of increasing antibody levels corresponding to the severity of mucosal damage. Large-scale primary research initiatives are needed to reach definitive conclusions.

A Clinician's Guide to Gluten Challenge

Gluten challenge is an essential clinical tool that involves reintroducing or increasing the amount of gluten in the diet to facilitate diagnostic testing in celiac disease (CD). Nevertheless, there is no consensus regarding the applications of gluten timing, dosing, and duration in children. This review aims to summarize the current evidence, discuss practical considerations, and proposes a clinical algorithm to help guide testing in pediatric patients. Childhood development, social circumstances, and long-term health concerns must be considered when identifying a candidate for gluten challenge. Based on previous studies, the authors suggest baseline serology followed by a minimum of 3-6 grams of gluten per day for over 12 weeks to optimize diagnostic accuracy for evaluation of CD. A formal provider check-in at 4-6 weeks is essential so the provider and family can adjust dosing or duration as needed. Increasing the dose of gluten further may improve diagnostic yield if tolerated, although in select cases a lower dose and shorter course (6-12 weeks) may be sufficient. There is consensus that mild elevations in celiac serology (<10 times the upper limit of normal) or symptoms, while supportive are not diagnostic for CD. Current North American Society for Pediatric Gastroenterology, Hepatology and Nutrition guidelines recommend histologic findings of intraepithelial lymphocytosis, crypt hyperplasia, and villous atrophy as the accurate and most appropriate endpoint for gluten challenge.

Celiac disease: mechanisms and emerging therapeutics

Celiac disease (CeD) is a widespread, gluten-induced, autoimmune disorder that lacks any medicinal therapy. Towards the goal of developing non-dietary treatments for CeD, research has focused on elucidating its molecular and cellular etiology. A model of pathogenesis has emerged centered on interactions between three molecular families: specific class II MHC proteins on antigen-presenting cells (APCs), deamidated gluten-derived peptides, and T cell receptors (TCRs) on inflammatory CD4+ T cells. Growing evidence suggests that this pathogenic axis can be pharmacologically targeted to protect patients from some of the adverse effects of dietary gluten. Further studies have revealed the existence of additional host and environmental contributors to disease initiation and tissue damage. This review summarizes our current understanding of CeD pathogenesis and how it is being harnessed for therapeutic design and development.

Biology and genetics of extranodal mature T-cell and NKcell lymphomas and lymphoproliferative disorders

The extranodal mature T-cell and NK-cell lymphomas and lymphoproliferative disorders represent a unique group of rare neoplasms with both overlapping and distinct clinicopathological, biological, and genomic features. Their predilection for specific sites, such as the gastrointestinal tract, aerodigestive tract, liver, spleen, and skin/soft tissues, underlies their classification. Recent genomic advances have furthered our understanding of the biology and pathogenesis of these diseases, which is critical for accurate diagnosis, prognostic assessment, and therapeutic decision-making. Here we review clinical, pathological, genomic, and biological features of the following extranodal mature T-cell and NK-cell lymphomas and lymphoproliferative disorders: primary intestinal T-cell and NK-cell neoplasms, hepatosplenic T-cell lymphoma, extranodal NK/T-cell lymphoma, nasal type, and subcutaneous panniculitis-like T-cell lymphoma.

Small Bowel Imaging in Celiac Disease: Is there a role for Small Bowel Ultrasound?

PURPOSE OF REVIEW

The incidence of celiac disease (CD) has increased over the last decades in part due to better disease awareness. Small bowel ultrasound (sb US) enables dynamic assessment of the bowel; although this topic has been addressed, the use of sb US in the diagnosis and in the follow-up of CD patients is limited to a few specialized tertiary referral centers. Herein, we aimed at summarizing the available literature on this topic to better define the potential clinical implications of sb US in CD, also through a comparison with other available diagnostic techniques.

RECENT FINDINGS

According to available data, sb US can be of help in confirming or excluding CD in patients with clinical suspicion; specifically, the finding of increased gall bladder volume, free abdominal fluid and enlargement of mesenteric lymph nodes reliably and accurately predicts the diagnosis of CD, whereas the absence of bowel dilatation and increased peristalsis may exclude the diagnosis. However, the place of intestinal US in the diagnostic algorithm of CD is likely to vary depending on the probability of the disease in a given population. There are only a few studies on the role of sb US in complicated CD, even if recent reports suggest a possible clinical role. There is a lack of data on follow-up of CD patients, particularly with the aim of detecting a poor diet adherence. According to current data sb US parameters have been shown to be of value in confirming and excluding the diagnosis of CD. Prospective studies with large sample size are warranted to determine whether to include sb US in the available guidelines for CD diagnosis and monitoring.

Symptom Outcomes of Celiac Disease in Those on a Gluten-free Diet

GOALS

We aimed to evaluate symptom outcomes in those on a gluten-free diet during the 5 years after diagnosis.

BACKGROUND

Celiac disease is common; however, little is known about long-term symptom outcomes.

STUDY

We performed a retrospective chart review on individuals with celiac disease followed at a tertiary referral center between 2012 and 2018. To minimize bias, strict inclusion/exclusion criteria were utilized. Only those with definitive biopsy-proven celiac disease, on a gluten-free diet, and with systematic follow-up were included. The standardized care at this center reduced the risk that decisions on testing and follow-up visits were determined by symptom status. Summary statistics were computed and generalized linear models with a logit link were used to associate the proportion of symptomatic visits with various covariates using R statistical programming.

RESULTS

Of the 1023 records reviewed, 212 met inclusion/exclusion criteria; 146 (69%) were female and the mean age at diagnosis was 43 (range: 11 to 84 y old). During follow-up, over 50% remained symptomatic, with many having the same symptoms that prompted the diagnosis. The only predictors for remaining symptomatic were female sex and younger age at diagnosis. Abnormal serology during follow-up and small bowel normalization were not predictive.

CONCLUSIONS

In individuals with definitive celiac disease with systematic long-term follow-up in a Celiac Clinic, roughly half remained symptomatic despite a gluten-free diet. Many suffer from the same symptoms that prompted the diagnosis of celiac disease. Small bowel healing and abnormal serology in follow-up were not predictive of remaining symptomatic. These findings stress the importance of long-term care in celiac disease.

Population level screening for celiac disease: is now the time?

PURPOSE OF REVIEW

As incidence and prevalence of celiac disease is increasing, subclinical and asymptomatic presentations are more commonly identified through celiac disease screening. However, the United States Preventive Services Task Force released a statement in 2017 maintaining that there is insufficient evidence to recommend general population screening for celiac disease for asymptomatic individuals. This review summarizes the current available evidence on celiac disease screening.

RECENT FINDINGS

Literature demonstrates that by limiting screening to individuals with recognized symptoms, celiac disease diagnosis is frequently delayed or missed entirely. Most individuals with screening-identified celiac disease have previously unrecognized symptoms that improve through treatment with a gluten-free diet. Screening-identified individuals also demonstrate signs of impaired nutrition, growth, bone health, and quality of life which improve with treatment. Overall, celiac disease screening is viewed favorably by those identified through celiac disease screening programs.

SUMMARY

Individuals with screening-identified celiac disease may still incur complications from untreated disease and receive benefit from treatment with a gluten-free diet. More data is needed to determine the cost effectiveness of different mass screening approaches that incorporate the societal perspective towards screening.

The Gluten-Free Diet for Celiac Disease: Critical Insights to Better Understand Clinical Outcomes

The gluten-free diet (GFD) remains a complex paradigm in managing celiac disease (CeD) in children and adults, and there are many reasons why GFD adherence should be strict to improve outcomes. However, this is a challenging task for patients, since they need to have access to quality healthcare resources that facilitate optimal GFD adherence. Understanding the strengths and weaknesses of the GFD, tackling coexisting nutritional deficiencies, and dealing with complex situations, such as seronegative CeD or non-responsive CeD, all require the involvement of a multidisciplinary team. The short- and long-term follow-up of CeD patients should preferably be performed by a combined Gastroenterology and Nutrition service with well-defined quality standards and the multidisciplinary involvement of physicians, nurses, dietitians, and psychologists. Nutritional advice and counseling by an experienced dietitian can reduce the costs associated with long-term follow-up of CeD patients. Likewise, psychological interventions may be essential in specific scenarios where implementing and sustaining a lifelong GFD can cause a significant psychological burden for patients. This manuscript aims to provide guidelines to improve clinical practice in the follow-up and monitoring of CeD patients and provide information on the nutritional risks of an ill-advised GFD. Clinicians, biochemists, food technologists, dietitians, and psychologists with a global view of the disease have been involved in its writing.