Gut microbiota predicts severity and reveals novel metabolic signatures in acute pancreatitis.

OBJECTIVE: Early disease prediction is challenging in acute pancreatitis (AP). Here, we prospectively investigate whether the microbiome predicts severity of AP (Pancreatitis-Microbiome As Predictor of Severity; P-MAPS) early at hospital admission. DESIGN: Buccal and rectal microbial swabs were collected from 424 patients with AP within 72 hours of hospital admission in 15 European centres. All samples were sequenced by full-length 16S rRNA and metagenomic sequencing using Oxford Nanopore Technologies. Primary endpoint was the association of the orointestinal microbiome with the revised Atlanta classification (RAC). Secondary endpoints were mortality, length of hospital stay and severity (organ failure >48 hours and/or occurrence of pancreatic collections requiring intervention) as post hoc analysis. Multivariate analysis was conducted from normalised microbial and corresponding clinical data to build classifiers for predicting severity. For functional profiling, gene set enrichment analysis (GSEA) was performed and normalised enrichment scores calculated. RESULTS: After data processing, 411 buccal and 391 rectal samples were analysed. The intestinal microbiome significantly differed for the RAC (Bray-Curtis, p value=0.009), mortality (Bray-Curtis, p value 0.006), length of hospital stay (Bray-Curtis, p=0.009) and severity (Bray-Curtis, p value=0.008). A classifier for severity with 16 different species and systemic inflammatory response syndrome achieved an area under the receiving operating characteristic (AUROC) of 85%, a positive predictive value of 67% and a negative predictive value of 94% outperforming established severity scores. GSEA revealed functional pathway units suggesting elevated short-chain fatty acid (SCFA) production in severe AP. CONCLUSIONS: The orointestinal microbiome predicts clinical hallmark features of AP, and SCFAs may be used for future diagnostic and therapeutic concepts. TRIAL REGISTRATION NUMBER: NCT04777812.

Type 1 Autoimmune Pancreatitis in Europe: Clinical Profile and Response to Treatment.

BACKGROUND & AIMS: Autoimmune pancreatitis (AIP) is an immune-mediated disease of the pancreas with distinct pathophysiology and manifestations. Our aims were to characterize type 1 AIP in a large pan-European cohort and study the effectiveness of current treatment regimens. METHODS: We retrospectively analyzed adults diagnosed since 2005 with type 1 or not-otherwise-specified AIP in 42 European university hospitals. Type 1 AIP was uniformly diagnosed using specific diagnostic criteria. Patients with type 2 AIP and those who had undergone pancreatic surgery were excluded. The primary end point was complete remission, defined as the absence of clinical symptoms and resolution of the index radiologic pancreatic abnormalities attributed to AIP. RESULTS: We included 735 individuals with AIP (69% male; median age, 57 years; 85% White). Steroid treatment was started in 634 patients, of whom 9 (1%) were lost to follow-up. The remaining 625 had a 79% (496/625) complete, 18% (111/625) partial, and 97% (607/625) cumulative remission rate, whereas 3% (18/625) did not achieve remission. No treatment was given in 95 patients, who had a 61% complete (58/95), 19% partial (18/95), and 80% cumulative (76/95) spontaneous remission rate. Higher (≥0.4 mg/kg/day) corticosteroid doses were no more effective than lower (<0.4 mg/kg/day) doses (odds ratio, 0.428; 95% confidence interval, 0.054-3.387) and neither was a starting dose duration >2 weeks (odds ratio, 0.908; 95% confidence interval, 0.818-1.009). Elevated IgG4 levels were independently associated with a decreased chance of complete remission (odds ratio, 0.639; 95% confidence interval, 0.427-0.955). Relapse occurred in 30% of patients. Relapses within 6 months of remission induction were independent of the steroid-tapering duration, induction treatment duration, and total cumulative dose. CONCLUSIONS: Patients with type 1 AIP and elevated IgG4 level may need closer monitoring. For remission induction, a starting dose of 0.4 mg/kg/day for 2 weeks followed by a short taper period seems effective. This study provides no evidence to support more aggressive regimens.

Nonalcoholic fatty liver disease, liver fibrosis, and structural brain imaging: The Cross-Cohort Collaboration.

BACKGROUND AND PURPOSE: Prior studies reported conflicting findings regarding the association of nonalcoholic fatty liver disease (NAFLD) and liver fibrosis with measures of brain health. We examined whether NAFLD and liver fibrosis are associated with structural brain imaging measures in middle- and old-age adults. METHODS: In this cross-sectional study among dementia- and stroke-free individuals, data were pooled from the Offspring and Third Generation cohorts of the Framingham Heart Study (FHS), the Rotterdam Study (RS), and the Study of Health in Pomerania. NAFLD was assessed through abdominal imaging. Transient hepatic elastography (FibroScan) was used to assess liver fibrosis in FHS and RS. Linear regression models were used to explore the relation of NAFLD and liver fibrosis with brain volumes, including total brain, gray matter, hippocampus, and white matter hyperintensities, adjusting for potential confounders. Results were combined using fixed effects meta-analysis. RESULTS: In total, 5660 and 3022 individuals were included for NAFLD and liver fibrosis analyses, respectively. NAFLD was associated with smaller volumes of total brain (ß = -3.5, 95% confidence interval [CI] = -5.4 to -1.7), total gray matter (ß = -1.9, 95% CI = -3.4 to -0.3), and total cortical gray matter (ß = -1.9, 95% CI = -3.7 to -0.01). In addition, liver fibrosis (defined as liver stiffness measure ≥8.2 kPa) was related to smaller total brain volumes (ß = -7.3, 95% CI = -11.1 to -3.5). Heterogeneity between studies was low. CONCLUSIONS: NAFLD and liver fibrosis may be directly related to brain aging. Larger and prospective studies are warranted to validate these findings and identify liver-related preventive strategies for neurodegeneration.

Activated regulatory T-cells promote duodenal bacterial translocation into necrotic areas in severe acute pancreatitis.

OBJECTIVE: In acute pancreatitis (AP), bacterial translocation and subsequent infection of pancreatic necrosis are the main risk factors for severe disease and late death. Understanding how immunological host defence mechanisms fail to protect the intestinal barrier is of great importance in reducing the mortality risk of the disease. Here, we studied the role of the Treg/Th17 balance for maintaining the intestinal barrier function in a mouse model of severe AP. DESIGN: AP was induced by partial duct ligation in C57Bl/6 or DEREG mice, in which regulatory T-cells (Treg) were depleted by intraperitoneal injection of diphtheria toxin. By flow cytometry, functional suppression assays and transcriptional profiling we analysed Treg activation and characterised T-cells of the lamina propria as well as intraepithelial lymphocytes (IELs) regarding their activation and differentiation. Microbiota composition was examined in intestinal samples as well as in murine and human pancreatic necrosis by 16S rRNA gene sequencing. RESULTS: The prophylactic Treg-depletion enhanced the proinflammatory response in an experimental mouse model of AP but stabilised the intestinal immunological barrier function of Th17 cells and CD8+/γδTCR+ IELs. Treg depleted animals developed less bacterial translocation to the pancreas. Duodenal overgrowth of the facultative pathogenic taxa Escherichia/Shigella which associates with severe disease and infected necrosis was diminished in Treg depleted animals. CONCLUSION: Tregs play a crucial role in the counterbalance against systemic inflammatory response syndrome. In AP, Treg-activation disturbs the duodenal barrier function and permits translocation of commensal bacteria into pancreatic necrosis. Targeting Tregs in AP may help to ameliorate the disease course.

Toll-Like Receptor 1 Locus Re-examined in a Genome-Wide Association Study Update on Anti-Helicobacter pylori IgG Titers.

BACKGROUND & AIMS: A genome-wide significant association between anti-Helicobacter pylori (H pylori) IgG titers and Toll-like receptor (TLR1/6/10) locus on 4p14 was demonstrated for individuals of European ancestry, but not uniformly replicated. We re-investigated this association in an updated genome-wide association study (GWAS) meta-analysis for populations with low gastric cancer incidence, address potential causes of cohort heterogeneity, and explore functional implications of genetic variation at the TLR1/6/10 locus. METHODS: The dichotomous GWAS (25% individuals exhibiting highest anti-H pylori IgG titers vs remaining 75%) included discovery and replication sampls of, respectively, n = 15,685 and n = 9676, all of European ancestry. Longitudinal analysis of serologic data was performed on H pylori-eradicated subjects (n = 132) and patients under surveillance for premalignant gastric lesions (n = 107). TLR1/6/10 surface expression, TLR1 mRNA, and cytokine levels were measured in leukocyte subsets of healthy subjects (n = 26) genotyped for TLR1/6/10 variants. RESULTS: The association of the TLR1/6/10 locus with anti-H pylori IgG titers (rs12233670; ß = -0.267 ± SE 0.034; P = 4.42 × 10-15) presented with high heterogeneity and failed replication. Anti-H pylori IgG titers declined within 2-4 years after eradication treatment (P = 0.004), and decreased over time in patients with premalignant gastric lesions (P < 0.001). Variation at the TLR1/6/10 locus affected TLR1-mediated cytokine production and TLR1 surface expression on monocytes (P = 0.016) and neutrophils (P = 0.030), but not mRNA levels. CONCLUSIONS: The association between anti-H pylori IgG titers and TLR1/6/10 locus was not replicated across cohorts, possibly owing to dependency of anti-H pylori IgG titers on therapy, clearance, and antibody decay. H pylori-mediated immune cell activation is partly mediated via TLR1 signaling, which in turn is affected by genetic variation.

From heterogeneous healthcare data to disease-specific biomarker networks: A hierarchical Bayesian network approach.

In this work, we introduce an entirely data-driven and automated approach to reveal disease-associated biomarker and risk factor networks from heterogeneous and high-dimensional healthcare data. Our workflow is based on Bayesian networks, which are a popular tool for analyzing the interplay of biomarkers. Usually, data require extensive manual preprocessing and dimension reduction to allow for effective learning of Bayesian networks. For heterogeneous data, this preprocessing is hard to automatize and typically requires domain-specific prior knowledge. We here combine Bayesian network learning with hierarchical variable clustering in order to detect groups of similar features and learn interactions between them entirely automated. We present an optimization algorithm for the adaptive refinement of such group Bayesian networks to account for a specific target variable, like a disease. The combination of Bayesian networks, clustering, and refinement yields low-dimensional but disease-specific interaction networks. These networks provide easily interpretable, yet accurate models of biomarker interdependencies. We test our method extensively on simulated data, as well as on data from the Study of Health in Pomerania (SHIP-TREND), and demonstrate its effectiveness using non-alcoholic fatty liver disease and hypertension as examples. We show that the group network models outperform available biomarker scores, while at the same time, they provide an easily interpretable interaction network.

Identification of early predictors for infected necrosis in acute pancreatitis.

BACKGROUND: In acute pancreatitis, secondary infection of pancreatic necrosis is a complication that mostly necessitates interventional therapy. A reliable prediction of infected necrotizing pancreatitis would enable an early identification of patients at risk, which however, is not possible yet. METHODS: This study aims to identify parameters that are useful for the prediction of infected necrosis and to develop a prediction model for early detection. We conducted a retrospective analysis from the hospital information and reimbursement data system and screened 705 patients hospitalized with diagnosis of acute pancreatitis who underwent contrast-enhanced computed tomography and additional diagnostic puncture or drainage of necrotic collections. Both clinical and laboratory parameters were analyzed for an association with a microbiologically confirmed infected pancreatic necrosis. A prediction model was developed using a logistic regression analysis with stepwise inclusion of significant variables. The model quality was tested by receiver operating characteristics analysis and compared to single parameters and APACHE II score. RESULTS: We identified a total of 89 patients with necrotizing pancreatitis, diagnosed by computed tomography, who additionally received biopsy or drainage. Out of these, 59 individuals had an infected necrosis. Eleven parameters showed a significant association with an infection including C-reactive protein, albumin, creatinine, and alcoholic etiology, which were independent variables in a predictive model. This model showed an area under the curve of 0.819, a sensitivity of 0.692 (95%-CI [0.547-0.809]), and a specificity of 0.840 (95%-CI [0.631-0.947]), outperforming single laboratory markers and APACHE II score. Even in cases of missing values predictability was reliable. CONCLUSION: A model consisting of a few single blood parameters and etiology of pancreatitis might help for differentiation between infected and non-infected pancreatic necrosis and assist medical therapy in acute necrotizing pancreatitis.

[The role of the microbiome in diseases of the pancreas]. / Rolle des Mikrobioms bei Erkrankungen des Pankreas.

BACKGROUND: The human body is inhabited by diverse microorganisms. Together, this so-called microbiome exerts important metabolic functions and contributes to the maintenance of health. At the same time, shifts in the microbiome composition may lead to disease. OBJECTIVES: Review of the current literature about the role of the microbiome in diseases of the pancreas. MATERIALS AND METHODS: Literature search in PubMed and Embase. RESULTS: The exocrine pancreas is a major factor determining the composition and stability of the intestinal microbiome even in healthy people without pancreatic disease. Inflammatory diseases of the pancreas such as acute or chronic pancreatitis lead to reduced microbial diversity, loss of gut barrier stabilizing bacteria and an increase in facultative pathogens like Escherichia or Enterococcus. Even pancreatic cancer tissue harbours microbiota and mice models have shown that the growth of pancreatic cancer can be inhibited by microbiota ablation. CONCLUSIONS: Inflammatory diseases of the pancreas lead to gut microbiome dysbiosis and tumor microbiota probably play a role in the development of pancreatic cancer. Until now, however, there is no proof that therapeutic microbiota modulation in individuals with pancreatic disease can improve mortality or quality of life. At this point, the analysis of the microbiome in pancreatic disease should only be performed in scientific studies.

Long-term instability of the intestinal microbiome is associated with metabolic liver disease, low microbiota diversity, diabetes mellitus and impaired exocrine pancreatic function.

OBJECTIVE: The intestinal microbiome affects the prevalence and pathophysiology of a variety of diseases ranging from inflammation to cancer. A reduced taxonomic or functional diversity of the microbiome was often observed in association with poorer health outcomes or disease in general. Conversely, factors or manifest diseases that determine the long-term stability or instability of the microbiome are largely unknown. We aimed to identify disease-relevant phenotypes associated with faecal microbiota (in-)stability. DESIGN: A total of 2564 paired faecal samples from 1282 participants of the population-based Study of Health in Pomerania (SHIP) were collected at a 5-year (median) interval and microbiota profiles determined by 16S rRNA gene sequencing. The changes in faecal microbiota over time were associated with highly standardised and comprehensive phenotypic data to determine factors related to microbiota (in-)stability. RESULTS: The overall microbiome landscape remained remarkably stable over time. The greatest microbiome instability was associated with factors contributing to metabolic syndrome such as fatty liver disease and diabetes mellitus. These, in turn, were associated with an increase in facultative pathogens such as Enterobacteriaceae or Escherichia/Shigella. Greatest stability of the microbiome was determined by higher initial alpha diversity, female sex, high household income and preserved exocrine pancreatic function. Participants who newly developed fatty liver disease or diabetes during the 5-year follow-up already displayed significant microbiota changes at study entry when the diseases were absent. CONCLUSION: This study identifies distinct components of metabolic liver disease to be associated with instability of the intestinal microbiome, increased abundance of facultative pathogens and thus greater susceptibility toward dysbiosis-associated diseases.

Nutritional management of chronic pancreatitis: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND AIM: Malnutrition is a frequent complication of chronic pancreatitis. Adequate nutritional support is imperative, but there is still uncertainty about the optimal nutritional treatment. This work systematically compiles evidence from randomized controlled trials investigating dietary interventions in chronic pancreatitis and, in a further step, contrasts those findings with existing dietary recommendations. METHODS: The literature search (PubMed and Cochrane Central Register of Controlled Trials) included English and German full-text articles, which had been published in peer-reviewed journals. Two independent reviewers identified and selected studies. For meta-analysis, forest plots with 95% confidence intervals were generated using a random-effects model. RESULTS: Eleven randomized controlled trials fulfilled all selection criteria. In these trials, the following dietary interventions were tested: antioxidant treatment (n = 6), vitamin D supplementation (n = 3), supplementation with oral nutritional supplements (n = 1), and symbiotics supplementation (n = 1). Studies were of good methodological quality (mean Jadad score of 3.6) but heterogeneous in terms of interventions and study populations. Only for vitamin D, there was convincing evidence for efficacy of supplementation. We found no effect for antioxidant treatment on pain relief (standardized mean difference = -0.12; 95% confidence interval -0.73 to 0.48) and limited generalizability for interventions with oral nutritional supplements and symbiotics. CONCLUSIONS: Nutritional management in chronic pancreatitis remains challenging. As well-designed randomized controlled trials are scarce, in large part, recommendations can only be based on low-level evidence studies or expert opinion. For now, consumption of a balanced diet remains the cornerstone recommendation for prevention, whereas more goal-directed interventions are indicated for specific nutrient deficiencies.

Effects of syntaxins 2, 3, and 4 on rat and human epithelial sodium channel (ENaC) in Xenopus laevis oocytes.

Syntaxins are SNARE proteins and may play a role in epithelial sodium channel (ENaC) trafficking. The aim of the present study was to investigate the effects of syntaxin 2 (STX2), syntaxin 3 (STX3), and syntaxin 4 (STX4) on rat (rENaC) and human ENaC (hENaC). Co-expression of rENaC and STX3 or STX4 in Xenopus laevis oocytes increased amiloride-sensitive whole-cell currents (ΔIami) on average by 50% and 135%, respectively, compared to oocytes expressing rENaC alone. In contrast, STX2 had no significant effect on rENaC. Similar to its effect on rENaC, STX3 stimulated hENaC by 48%. In contrast, STX2 and STX4 inhibited hENaC by 51% and 44%, respectively. Using rENaC carrying a FLAG tag in the extracellular loop of the ß-subunit, we demonstrated that the stimulatory effects of STX3 and STX4 on ΔIami were associated with an increased expression of the channel at the cell surface. Co-expression of STX3 or STX4 did not significantly alter the degree of proteolytic channel activation by chymotrypsin. STX3 had no effect on the inhibition of rENaC by brefeldin A, and the stimulatory effect of STX3 was preserved in the presence of dominant negative Rab11. This indicates that the stimulatory effect of STX3 is not mediated by inhibiting channel retrieval or by stimulating fusion of recycling endosomes. Our results suggest that the effects of syntaxins on ENaC are isoform and species dependent. Furthermore, our results demonstrate that STX3 increases ENaC expression at the cell surface, probably by enhancing insertion of vesicles carrying newly synthesized channels.

Impaired Exocrine Pancreatic Function Associates With Changes in Intestinal Microbiota Composition and Diversity.

BACKGROUND & AIMS: Changes in intestinal microbiome composition are associated with inflammatory, metabolic, and malignant disorders. We studied how exocrine pancreatic function affects intestinal microbiota. METHODS: We performed 16S ribosomal RNA gene sequencing analysis of stool samples from 1795 volunteers from the population-based Study of Health in Pomerania who had no history of pancreatic disease. We also measured fecal pancreatic elastase by enzyme-linked immunosorbent assay and performed quantitative imaging of secretin-stimulated pancreatic fluid secretion. Associations of exocrine pancreatic function with microbial diversity or individual genera were calculated by permutational analysis of variance or linear regression, respectively. RESULTS: Differences in pancreatic elastase levels associated with significantly (P < .0001) greater changes in microbiota diversity than with participant age, body mass index, sex, smoking, alcohol consumption, or dietary factors. Significant changes in the abundance of 30 taxa, such as an increase in Prevotella (q < .0001) and a decrease of Bacteroides (q < .0001), indicated a shift from a type-1 to a type-2 enterotype. Changes in pancreatic fluid secretion alone were also associated with changes in microbial diversity (P = .0002), although to a lesser degree. CONCLUSIONS: In an analysis of fecal samples from 1795 volunteers, pancreatic acinar cell, rather than duct cell, function is presently the single most significant host factor to be associated with changes in intestinal microbiota composition.

Examination of duodenal and colonic microbiome changes in mouse models of acute and chronic pancreatitis.

The exocrine pancreas is the main source of digestive enzymes which are released from secretory vesicles of acinar cells into the small intestine. Enzymes, including amylases, proteases and lipases, degrade the ingested food and thus determine the nutritional substrate for the gut microbiota. Acute (AP) and chronic pancreatitis (CP) are associated with a transitional or progressive exocrine pancreatic dysfunction, we analysed in the present study how an experimental induction of pancreatitis in mouse models affects the colonic and duodenal microbiome composition. Evaluation by 16 S rRNA gene sequencing revealed specific microbiome changes in colonic as well as in duodenal samples in different models of AP and CP. Mild acute pancreatitis, which is associated with a transient impairment of pancreatic secretion showed only minor changes in microbial composition, comparable to the ones seen in progressive dysfunctional mouse models of CP. The strongest changes were observed in a mouse model of severe AP, which suggest a direct effect of the immune response on gut microbiome in addition to a pancreatic dysfunction. Our data indicate that highly dysbiotic microbiome changes during pancreatitis are more associated with the inflammatory reaction than with a disturbed pancreatic secretion.

On the limits of 16S rRNA gene-based metagenome prediction and functional profiling.

Molecular profiling techniques such as metagenomics, metatranscriptomics or metabolomics offer important insights into the functional diversity of the microbiome. In contrast, 16S rRNA gene sequencing, a widespread and cost-effective technique to measure microbial diversity, only allows for indirect estimation of microbial function. To mitigate this, tools such as PICRUSt2, Tax4Fun2, PanFP and MetGEM infer functional profiles from 16S rRNA gene sequencing data using different algorithms. Prior studies have cast doubts on the quality of these predictions, motivating us to systematically evaluate these tools using matched 16S rRNA gene sequencing, metagenomic datasets, and simulated data. Our contribution is threefold: (i) using simulated data, we investigate if technical biases could explain the discordance between inferred and expected results; (ii) considering human cohorts for type two diabetes, colorectal cancer and obesity, we test if health-related differential abundance measures of functional categories are concordant between 16S rRNA gene-inferred and metagenome-derived profiles and; (iii) since 16S rRNA gene copy number is an important confounder in functional profiles inference, we investigate if a customised copy number normalisation with the rrnDB database could improve the results. Our results show that 16S rRNA gene-based functional inference tools generally do not have the necessary sensitivity to delineate health-related functional changes in the microbiome and should thus be used with care. Furthermore, we outline important differences in the individual tools tested and offer recommendations for tool selection.

An intensified trans-sectoral nutritional intervention in malnourished patients with chronic pancreatitis improves diseases prognosis and identifies potential biomarkers of nutritional status.

Background: Malnutrition is a common complication in chronic pancreatitis and associated with reduced quality of life and life expectancy. Nutritional support is considered mandatory in malnourished patients with chronic pancreatitis but there is only scarce evidence on optimal treatment modalities and the efficacy of nutrition therapy. Here, we investigated the feasibility and efficacy of an intensified nutritional intervention in malnourished patients with chronic pancreatitis and aimed to identify suitable indicators for monitoring nutritional status. Methods: We performed a single-arm feasibility study, in which malnourished patients with chronic pancreatitis received an intensified trans-sectoral nutritional intervention for 6 months. Multimodal treatment comprised face-to-face dietary counseling, oral nutritional supplementation, and a complementary telephone-based nutrition and exercise coaching. Patients underwent follow-up examinations after 28, 90, and 180 days, when we assessed changes in anthropometric and body composition measures, muscle function, Chronic Pancreatitis Prognosis Score (COPPS), as well as blood parameters and intestinal microbiota composition. Results: Eleven out of 73 patients initially screened for study participation were enrolled in the trial of which 9 subjects (age (mean ± SD): 56.2 (±14.8) years; male: 67%; alcoholic etiology: 44%) underwent the complete intervention. Patients gained a median of 5.3 kg (8.6%) body weight, including 1.6 kg skeletal muscle mass, and significantly increased gait speed (p < 0.001). Ameliorated nutritional status and muscle function were associated with increased blood levels of IGF-1 and cholinesterase as well as altered gut microbiota composition on the phyla and genera level. Moreover, significant improvements in COPPS indicated reduced disease severity after 90 and 180 days. Conclusion: Malnourished patients with chronic pancreatitis benefit from intensified nutritional therapy. Besides ameliorated nutritional status, a multimodal intervention can improve muscle function as well disease prognosis. Future studies are needed to prove superiority to standard-of-care and to validate potential biomarkers for prospective monitoring of nutritional status. Clinical trial registration: https://clinicaltrials.gov/study/NCT04476056, NCT04476056.

Loss of mucosal tolerance to glycoprotein 2 isoform 1 is a potential novel diagnostic biomarker for cholangiocarcinoma.

BACKGROUND: Anti-glycoprotein 2 (anti-GP2) IgA and antineutrophil-cytoplasmic antibodies to proteinase 3 (PR3-ANCA) have been reported as predictive markers of cholangiocarcinoma (CCA) in patients with primary sclerosing cholangitis (PSC), but their prevalence in CCA patients without PSC remains unclear. METHODS: This study involved Asian discovery (n = 118) and European validation (n = 38) cohorts of CCA patients without PSC, alongside 49 Asian and 82 European pancreatic ductal adenocarcinoma (PDAC) patients, 21 with benign pancreatic neoplasms (BPN) and 45 with hepatocellular carcinoma (HCC), and 157 healthy controls (HC) from Asia and Europe. We analyzed the prevalence of PR3-ANCA, IgA and IgG against GP21 and GP24, and the CA19-9 levels. RESULTS: Anti-GP21 IgA was the most prevalent in both CCA cohorts (discovery: 55.1 %; validation: 42.1 %) and significantly higher than in other groups except PDAC (all p < 0.05). It demonstrated the best diagnostic performance in distinguishing CCA from disease controls and HC, outperforming tumor markers. No significant correlation was found between anti-GP21 IgA levels and CA19-9 levels. CONCLUSION: Our findings show that anti-GP21 IgA revealing the loss of mucosal tolerance is a potential novel diagnostic biomarker for CCA.

Fecal glycoprotein 2 is a marker of gut microbiota dysbiosis and systemic inflammation.

BACKGROUND: Antimicrobial autoantigenic glycoprotein 2 (GP2) is an important component of the innate immune system which originates from the exocrine pancreas as well as from the small intestines. The relationship of GP2 with the intestinal microbiome as well as the systemic implications of increased fecal GP2 levels are, however, still unclear. Therefore, fecal samples from 2,812 individuals of the Study of Health in Pomerania (SHIP) were collected to determine GP2 levels (enzyme-linked immunosorbent assay) and gut microbiota profiles (16 S rRNA gene sequencing). These data were correlated and associated with highly standardised and comprehensive phenotypic data of the study participants. RESULTS: Fecal GP2 levels were increased in individuals with higher body mass index and smokers, whereas lower levels were found in case of preserved exocrine pancreatic function, female sex or a healthier diet. Moreover, higher GP2 levels were associated with increased serum levels of high-sensitivity C-reactive protein, loss of gut microbial diversity and an increase of potentially detrimental bacteria (Streptococcus, Haemophilus, Clostridium XIVa, or Collinsella). At the same time, predicted microbial pathways for the biosynthesis of beneficial short-chain fatty acids or lactic acid were depleted in individuals with high fecal GP2. Of note, GP2 exhibited a stronger association to overall microbiome variation than calprotectin. CONCLUSION: Fecal GP2 is a biomarker of gut microbiota dysbiosis and associated with increased systemic inflammation. The intestines may be more important as origin for GP2 than pancreatic acinar cells. Future studies need to investigate the potential clinical value in disease specific patient cohorts.

Nutritional status in patients with chronic pancreatitis and liver cirrhosis is related to disease conditions and not dietary habits.

Malnutrition is a common complication of chronic pancreatitis (CP) and liver cirrhosis (LC). Inadequate food intake is considered a relevant driver of malnutrition in both entities. However, the contribution of habitual diet to impaired nutritional status is unclear. In a prospective, multicenter cross-sectional study, we recruited patients with confirmed CP or LC and healthy volunteers as a control group. Malnutrition was diagnosed according to the Global Leadership Initiative on Malnutrition criteria. We comprehensively investigated habitual dietary intake on nutrient, food group, and dietary pattern level applying two validated food frequency questionnaires. We included 144 patients (CP: n = 66; LC: n = 78) and 94 control subjects. Malnutrition was prevalent in 64% and 62% of patients with CP or LC, respectively. In both CP and LC, despite slightly altered food group consumption in malnourished and non-malnourished patients there were no differences in energy or nutrient intake as well as dietary quality. Compared to controls patients showed distinct dietary food group habits. Patients consumed less alcohol but also lower quantities of fruits and vegetables as well as whole grain products (p < 0.001, respectively). Nevertheless, overall dietary quality was comparable between patients and healthy controls. Nutritional status in CP and LC patients is rather related to disease than habitual dietary intake supporting the relevance of other etiologic factors for malnutrition such as malassimilation or chronic inflammation. Despite distinct disease-related differences, overall dietary quality in patients with CP or LC was comparable to healthy subjects, which suggests susceptibility to dietary counselling and the benefits of nutrition therapy in these entities.

The composition of the stent microbiome is associated with morbidity and adverse events during endoscopic drainage therapy of pancreatic necroses and pseudocysts.

Background: Development of pancreatic necroses or pseudocysts are typical complications of pancreatitis and may require endoscopic drainage therapy using metal or plastic stents. Microbial infection of these lesions poses a major challenge. So far, the composition and significance of the microbial colonization on drainage stents are largely unknown although it may impact outcomes during endoscopic drainage therapy. Methods: A total of 26 stents used for drainage of pancreatic lesions were retrieved and the stent microbiome was determined by 16S rRNA gene sequencing. Additional analysis included comparison of the stent microbiome to the intracavitary necrosis microbiome as well as scanning electron microscopy (SEM) and micro-computed tomography (µCT) imaging of selected metal or plastic stents. Results: The stent microbiome comprises a large proportion of opportunistic enteric pathogens such as Enterococcus (14.4%) or Escherichia (6.1%) as well as oral bacteria like Streptococcus (13.1%). Increased levels of opportunistic enteric pathogens were associated with a prolonged hospital stay (r = 0.77, p = 3e-06) and the occurrence of adverse events during drainage therapy (p = 0.011). Higher levels of oral bacteria were associated (r = -0.62, p = 8e-04) with shorter durations of inpatient treatment. SEM and µCT investigations revealed complex biofilm networks on the stent surface. Conclusion: The composition of the stent microbiome is associated with prolonged hospital stays and adverse events during endoscopic drainage therapy, highlighting the need for effective infection control to improve patient outcomes. In addition to systemic antibiotic therapy, antimicrobial stent coatings could be a conceivable option to influence the stent microbiome and possibly enhance control of the necrotic microflora.