Choung, Rok Seon

ABSTRACT Coeliac disease (CeD) and immunoglobulin A deficiency (IgAD) frequently co‐occur and share a genetic background within the HLA‐DQ2 region. Although this has been known for decades, the underlying mechanisms linking the two conditions remain unclear. We conducted a scoping review to evaluate the prevalence, clinical characteristics, diagnostic challenges and histopathological features of IgAD in patients with CeD. Thirty‐one studies published between 1985 and 2024 were included. IgAD was more prevalent among individuals with CeD, 1.4%–4.8% than in the general population, and CeD occurred in 5.9%–14.1% of patients with IgAD. Most patients presented with gastrointestinal symptoms, although selection bias was common. IgG‐based serology remains essential for diagnosis and monitoring, but its reliability during follow‐up is limited by the slow decline of antibodies. Histological findings indicate compensatory IgM and IgG responses and persistent mucosal immune activation. Improved strategies for diagnosis and long‐term monitoring of patients with both conditions are warranted.

ABSTRACT Background Immune checkpoint inhibitors (ICIs) enhance anti‐tumour immunity by modulating immune pathways but can also trigger immune‐related adverse events. We aimed to evaluate the risk of developing coeliac disease (CeD) among patients with malignancy treated with ICIs. Methods Using the TriNetX US Collaborative Network, we identified adults (≥ 18 years) diagnosed with malignancies for which ICIs are routinely used between January 2010 and December 2024 and stratified them by exposure to immune checkpoint inhibitors (nivolumab, pembrolizumab, ipilimumab, atezolizumab, durvalumab, tremelimumab, or avelumab). Patients with pre‐existing celiac disease (CeD) were excluded. Cohorts were propensity score matched for demographics and autoimmune comorbidities. The primary outcome was incident CeD occurring ≥ 90 days after the index event. Adjusted hazard ratios (aHRs) were calculated, with subgroup analyses by age and sex. Statistical significance was defined as p < 0.05. Results After propensity score matching, 158,208 patients were included in each cohort. CeD was diagnosed more frequently among patients exposed to ICIs than among matched controls (0.152% vs. 0.071%; aHR 3.95, 95% CI 3.11–5.03; p < 0.001), corresponding to a number needed to harm (NNH) of 1235. The increased risk persisted across sex and age subgroups, including females (aHR 3.43, 95% CI 2.55–4.62), males (aHR 5.36, 95% CI 3.53–8.12), with the risk being highest among patients older than 60 years (0.14% vs. 0.06%; aHR 4.24, 95% CI 3.17–5.67; p < 0.001). Conclusion In this large real‐world cohort, ICI exposure was associated with nearly a fourfold increase in the risk of being diagnosed with CeD compared with matched controls.

Abstract Genome-resolved virome analysis remains inaccessible for many samples, including those with clinical relevance, because viral nucleic acid recovered after enrichment is often too scarce to support de novo genome assembly. As a result, many analyses are limited to sparse read-level detection, which cannot recover divergent viruses, resolve strains, or interpret gene-level variation. Here, we developed Low Biomass Viral Sequencing (LBV-Seq), a workflow that couples low-input viral sample handling with modified primary template-directed amplification and short- or long-read sequencing to enable de novo reconstruction of DNA and RNA viral genomes from sub-femtogram to nanogram inputs. LBV-Seq reproducibly captures the same relative community composition, amplifies diverse viruses, and achieved broad genome coverage across nearly all targets regardless of viral genome structure, Baltimore class, abundance, or input mass. Short-read assemblies recovered near-complete genomes from femtogram-scale inputs. Long-read sequencing provided orthogonal support for genome structure, with PacBio HiFi reads spanning large portions of viral genomes and, in some cases, complete small viral genomes. Applied to virus-enriched human duodenal biopsy eluates, LBV-Seq provided proof-of-feasibility for recovering both bacteriophage and eukaryotic viral genomes from low-input biopsy-derived material. In the eluates tested, LBV-Seq recovered co-occurring Alphatorquevirus and Betatorquevirus genomes estimated to be present at roughly 10 copies/µL and at viral masses below 0.1 fg/µL. LBV-Seq enables genome-resolved virome analysis in samples previously limited to detection-based viromics, supporting viral discovery and strain-resolved analyses in settings where viral mass is low, including viruses enriched from human tissue biopsies.

Abstract Background and Aims Celiac disease (CeD) is a chronic digestive autoimmune disorder affecting approximately 1% of the worldwide population. It is driven by T cells activated by specific HLA-DQ2 or HLA-DQ8 molecules leading to the destruction of intestinal villi. We aimed to characterize shared CeD-specific T cells in patients on and off a gluten-free diet (GFD) from a large cohort of cases and controls. Methods We performed bulk TCRβ immune sequencing of the peripheral blood of 1,604 biopsy-confirmed CeD patients (1,339 on GFD, 265 on normal diet) and 1,100 controls. We identified over 300 TCRβs enriched in CeD cases versus controls in an HLA-aware manner, controlling for CeD risk alleles. Results CeD-associated TCRβs were found to be more predictive of disease than previously characterized gliadin and glutenin-binding TCRs in a validation cohort. Furthermore, the clonal breadth of these TCRβs was associated with increased intestinal damage. Immune sequencing of the peripheral blood also uncovered repertoire-level differences between CeD patients and controls. CeD patients displayed significantly higher productive clonality compared to age-matched controls as well as expansion of TCRβs specific to cytomegalovirus (CMV) and Epstein-Barr Virus (EBV). Conclusions These findings underscore the value of unbiased immune repertoire sequencing to identify novel biomarkers for autoimmune disease and to discover new disease mechanisms which can improve both diagnosis and treatment of disease.

Abstract Background Celiac disease (CeD) has an estimated prevalence of 1%–3%. The classical clinical presentation is malabsorption, but now patients may present with more subtle symptoms such as constipation, osteoporosis, or iron deficiency anemia. Children may also present with poor growth. CeD has a strong genetic component, and high-risk groups include first-degree relatives with CeD, patients with co-existing autoimmune diseases, and patients with chromosomal aberrations. Content Diagnostic tests for CeD include duodenal histology, serology, and genetic testing. Duodenal histology has traditionally been the gold standard of diagnosis. However, serological tests, especially IgA tissue transglutaminase antibodies (TTG-IgA), are widely used and diagnostic algorithms are based primarily on TTG-IgA as a starting point. Human leukocyte antigen typing may also be incorporated to determine genetic risk for CeD. Guidelines for children endorse biopsy avoidance provided high levels of TTG-IgA, with diagnostic accuracy being comparable to duodenal biopsy. Confirmation may be achieved by identifying IgA endomysial antibodies in a separate blood sample. Subjects with low positive TTG-IgA levels and subjects with IgA deficiency need a biopsy to establish a diagnosis of CeD. The clinical follow-up of CeD usually includes a repeat TTG-IgA examination. In adults, healing may be delayed or incomplete, and a rare consequence of refractory celiac disease is transformation to enteric T-cell lymphoma. Summary Laboratory testing, in particular TTG-IgA, plays a central role in the diagnosis and has an accuracy comparable to histology. Diagnostic algorithms utilizing laboratory testing are critical for the development of novel strategies to improve diagnosis.

Serologic measures of tissue transglutaminase (tTG) immunoglobulin A (IgA) and deamidated gliadin peptide (DGP) IgA and immunoglobulin G (IgG) are hallmark tests utilized when diagnosing individuals for celiac disease (CeD) and for monitoring adherence to a gluten-free diet (GFD), currently the only available treatment for CeD. We address two issues in this study: (i) the relapse to seropositivity for CeD patients who resume a gluten containing diet and (ii) the correlation between two different tTG-IgA assays near the upper limit of normal (ULN) designated thresholds. Regarding the first issue, often a suspected CeD individual is put back on a gluten diet to return to their serologic levels. However, we show it requires a substantial amount of gluten for serology to return to a positive level. For example, in one study of 22 patients treated with placebo and taking 84 g of gluten over 6 weeks, only two converted from seronegative to seropositive for tTG-IgA. Regarding the second topic, we compare the relationship for different serologic assays, namely tTG-IgA AB (recombinant, ULN = 4 units/mL) vs. tTG-IgA (non-recombinant, ULN = 20 units). There is a strong correlation between both measurements as evidenced by a Pearson coefficient of R = 0.8584; however, we observed that the cross-correlation in terms of sensitivity and specificity improved substantially by using an ULN value of three instead of four for the tTG-IgA AB (recombinant) assay. This result suggests that assay thresholds used for initial diagnosis in patients who have not yet started a GFD may need to be adjusted for monitoring and in the setting of a diagnostic gluten challenge.

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.

Background Therapy for celiac disease (CD) mainly relies on following a gluten‐free diet (GFD); however, a serum marker for gluten intake has yet to be established. Aims To evaluate the utility of alkylresorcinol concentrations for detecting gluten intake in studies of human and mouse. Methods Alkylresorcinol concentrations were compared among treated CD patients (n=34), untreated CD patients (n=36), and controls (n=33). Furthermore, 7 additional CD patients whose serum samples were available at diagnosis and after GFD were evaluated. In mice studies, alkylresorcinol concentrations were compared in the serum of 5 mice fed a regular chow and 10 mice fed lifelong with a gluten‐free chow. In addition, the effect of adding gluten on changes of alkylresorcinol concentrations was also evaluated. Results Total alkylresorcinol concentrations were significantly lower in treated CD patients (median [IQR], 3 (2–8) nmol/L), compared to untreated CD patients (median [IQR], 32 [11–74] nmol/L; P<.0001) or healthy controls (median [IQR], 54 [23–112] nmol/L; P<.0001). Moreover, alkylresorcinol concentrations in CD patients significantly decreased after introduction of a GFD (median, 34 nmol/L at diagnosis vs. 5 nmol.L after GFD, p=0.02). In the mice, median (IQR) total alkylresorcinol concentrations in serum samples of mice fed lifelong with a gluten‐free chow was 1.8 (1.6–2.3) nmol/L, which was further significantly increased to 16 (11–22) nmol/L after 8 days of feeding with the gluten free chow that had gluten added to it. (p=.008). Conclusion Serum alkylresorcinol concentrations could be a useful marker for dietary gluten in CD. Support or Funding Information No funding to report.

ABSTRACTObjective:The aim of our study was to assess the response to hepatitis B virus (HBV) vaccination and the risk of HBV infection in patients with celiac disease (CD).Patients and Methods:We performed a cross‐sectional study using the National Health and Nutrition Examination Survey (NHANES) database (2009–2014) to assess the rate of HBV vaccination, immune response, and HBV infection risk in patients with and without CD. We also determined the rate of HBV infection via retrospective analysis of two cohorts: patients seen at Mayo Clinic (1998–2021), and a stable longitudinally observed cohort, the Rochester Epidemiology Project (REP; 2010–2020).Results:Based on the NHANES data, the rate of HBV infection in the United States was 0.33% (95% confidence interval 0.25–0.41). Of 93 patients with CD, 46 (49%) were vaccinated for HBV and of the remaining 19,422 without CD, 10,228 (53%) were vaccinated. Twenty‐two (48%) vaccinated patients with CD had HBV immunity and 4405 (43.07%) vaccinated patients without CD had HBV immunity, which was not statistically different. In NHANES data, there were no cases of HBV infection in patients with CD. During the study period, 3568 patients with CD were seen at Mayo Clinic and 3918 patients with CD were identified using the REP database. Of those patients with CD, only four (0.11%) at Mayo Clinic and nine (0.23%) of the REP patients had HBV infection.Conclusion:The rate of HBV vaccination and immunity was similar in individuals with and without CD. Predictably, no increased risk of HBV infection was detected in CD patients. These results do not support screening and revaccination practice for HBV immunity in patients with CD within the United States.

INTRODUCTION: Treated patients with celiac disease (CeD) and nonceliac gluten sensitivity (NCGS) report acute, transient, incompletely understood symptoms after suspected gluten exposure. To determine whether (i) blinded gluten exposure induces symptoms, (ii) subjects accurately identify gluten exposure, and (iii) serum interleukin-2 (IL-2) levels distinguish CeD from NCGS subjects after gluten exposure. METHODS: Sixty subjects (n = 20 treated, healed CeD; n = 20 treated NCGS; n = 20 controls) were block randomized to a single, double-blind sham (rice flour) or 3-g gluten challenge with 72-hours follow-up. Twelve serial questionnaires (100 mm visual analog scale; pain, bloating, nausea, and fatigue) and 10 serial plasma samples were collected. Mucosal permeability was assessed using both urinary lactulose- 13 C mannitol ratios and endoscopic mucosal impedance. RESULTS: Thirty-five of 40 (83%) subjects with CeD and NCGS reported symptoms with gluten (8 CeD, 9 NCGS) and sham (9 CeD, 9 NCGS) compared with 9 of 20 (45%) controls after gluten (n = 6) and sham (n = 3). There was no significant difference in symptoms among groups. Only 2 of 10 subjects with CeD and 4 of 10 NCGS identified gluten, whereas 8 of 10 subjects with CeD and 5 of 10 NCGS identified sham. A significant plasma IL-2 increase occurred only in subjects with CeD after gluten, peaking at 3 hours and normalizing within 24 hours postchallenge despite no significant intestinal permeability change from baseline. DISCUSSION: Symptoms do not reliably indicate gluten exposure in either subjects with CeD or NCGS. IL-2 production indicates a rapid-onset gluten-induced T-cell activation in CeD despite long-standing treatment. The effector site is unknown, given no increased intestinal permeability after gluten.