Pinch Biopsies Research Articles

Evaluating the feasibility and predictive accuracy of biodynamic imaging to platinum-based chemotherapy response in esophageal adenocarcinoma.

Esophageal cancer management lacks reliable response predictors to chemotherapy. In this study we evaluated the feasibility and accuracy of Biodynamic Imaging (BDI), a technology that employs digital holography as a rapid predictor of chemotherapy sensitivity in locoregional esophageal adenocarcinoma. Pre-treatment endoscopic pinch biopsies were collected from patients with esophageal adenocarcinoma during standard staging procedures. BDI analyzed the tumor samples and assessed in vitro chemotherapy sensitivity. BDI sensitivity predictions were compared to patients' pathological responses, the gold standard for determining clinical response, in the surgically treated subset (n=18). BDI was feasible with timely tissue acquisition, collection, and processing in all 30 enrolled patients and successful BDI analysis in 28/29 (96%) eligible. BDI accurately predicted chemotherapy response in 13/18 (72.2%) patients using a classifier for complete, marked, and partial/no-response. BDI technology had 100% negative predictive value for complete pathological response hence identifying patients unlikely to respond to treatment. BDI technology can potentially predict patients' response to platinum chemotherapy. Additionally, this technology represents a promising step towards optimizing treatment strategies for esophageal adenocarcinoma patients by pre-emptively identifying non-responders to conventional platinum-based chemotherapy.

Gastric-type extremely well-differentiated adenocarcinoma of the stomach: A rare tumor with diagnostic difficulties and high inter-observer variation in endoscopic pinch biopsies

Extremely well-differentiated gastric-type adenocarcinoma (EWDGA) is a rare type of gastric cancer composed of deceptively bland-looking malignant cells resembling normal foveolar or pyloric epithelium. The histological features of this tumor have not been recognized by many pathologists, and inter-observer variation studies are lacking. Here, we report seven EWDGAs and inter-observer variation of six preoperative biopsies was evaluated by 11 pathologists in a single institute. Based on the pathological diagnosis of the endoscopic biopsy slides, the average rate of definite malignancy diagnosis was 15.2 %, and the overall diagnostic concordance rate was 34.9 % among 11 pathologists. Microscopically, the surface epithelium was preserved and only a few atypical tumor glands were scattered in most endoscopic biopsies. Structural atypia was minimal, and the tumor glands were barely distinguishable from normal glands. Although nuclear atypia was minimal, enlarged nuclei, relatively large glands with irregular shapes, and abundant cytoplasmic mucin were observed in gastric pinch biopsies. In preoperative biopsies, no cases showed p53 overexpression, and Ki-67 labeling index ranged from 3 % to 35 % and was higher compared to non-neoplastic glands in 3 cases. After gastrectomy, four (57.1 %) patients had advanced gastric cancer and three (42.9 %) had lymph node metastasis. Genomic profiling of the four patients revealed mutations of TP53, BRAF, KRAS, STK11, and MDM2/CCND1 amplification. Immunohistochemistry for p53 was not helpful while Ki-67 may be helpful when staining pattern is distinct from the non-neoplastic mucosa. In conclusion, it is challenging to diagnose EWDGA using biopsy specimens. Recognizing and addressing this rare entity will increase diagnostic accuracy to ensure the early diagnosis of cancer.

Disaccharidase deficiencies and gastrointestinal symptoms in patients referred to gastroscopic examination: a single center study from Norway

Objective Gastrointestinal illnesses have been reported in relation to low disaccharidase activity, yet both the prevalence of disaccharidase deficiency and its association with gastrointestinal symptoms and irritable bowel syndrome (IBS) are largely unknown. We aimed to determine the association between low activity of disaccharidase enzymes on gastrointestinal symptoms and presence of IBS. Methods Patients referred for gastroscopic examination due to gastrointestinal complaints were consecutively included. A pinch biopsy was taken from the distal part of duodenum, and disaccharidase activity was measured using the Dahlqvist method. Gastrointestinal symptom severity was measured using IBS-Symptom Severity Score (IBS-SSS). Results A total of 40 patients were included. Disaccharidase deficiency was detected in 24 patients (60%). Half of the patients (n = 21) had IBS according to Rome IV criteria. A majority (75%) of all patients reported moderate to severe gastrointestinal symptoms. Moderate to severe gastrointestinal symptoms were reported by 16 patients (67%) with disaccharidase deficiency and in 14 patients (88%) with normal disaccharidase activity. Lactase deficiency was detected in 22 patients (55%), maltase deficiency in 11 patients (28%), sucrase deficiency in 9 patients (23%), isomaltase deficiency in 13 patients (33%) and glucoamylase deficiency in 12 patients (30%). The activity of all enzymes was reduced in 8 patients (20%). Degree of disaccharidase deficiency was not associated with either the severity of gastrointestinal symptoms or the diagnosis of IBS. Enzymes levels were not associated with gastrointestinal symptom scores. Conclusion Our findings did not reveal any association between biochemically measured disaccharidase deficiency and gastrointestinal symptoms or the presence of IBS.

Single nuclear RNA sequencing of terminal ileum in patients with cirrhosis demonstrates multi-faceted alterations in the intestinal barrier

Patients with cirrhosis have intestinal barrier dysfunction but the role of the individual cell types in human small intestine is unclear. We performed single-nuclear RNA sequencing (snRNAseq) in the pinch biopsies of terminal ileum of four age-matched men [56 years, healthy control, compensated, early (ascites and lactulose use) and advanced decompensated cirrhosis (ascites and rifaximin use)]. Cell type proportions, differential gene expressions, cell-type specific pathway analysis using IPA, and cellular crosstalk dynamics were compared. Stem cells, enterocytes and Paneth cells were lowest in advanced decompensation. Immune cells like naive CD4 + T cells were lowest while ITGAE + cells were highest in advanced decompensation patients. MECOM had lowest expression in stem cells in advanced decompensation. Defensin and mucin sulfation gene (PAPSS2) which can stabilize the mucus barrier expression were lowest while IL1, IL6 and TNF-related genes were significantly upregulated in the enterocytes, goblet, and Paneth cells in decompensated subjects. IPA analysis showed higher inflammatory pathways in enterocytes, stem, goblet, and Paneth cells in decompensated patients. Cellular crosstalk analysis showed that desmosome, protease-activated receptors, and cadherin-catenin complex interactions were most perturbed in decompensated patients. In summary, the snRNAseq of the human terminal ileum in 4 subjects (1 control and three cirrhosis) identified multidimensional alteration in the intestinal barrier with lower stem cells and altered gene expression focused on inflammation, mucin sulfation and cell–cell interactions with cirrhosis decompensation.

Validation of a real-time quaking-induced conversion (RT-QuIC) assay protocol to detect chronic wasting disease using rectal mucosa of naturally infected, pre-clinical white-tailed deer (Odocoileus virginianus).

Chronic wasting disease (CWD) is a fatal prion disease of cervids spreading across North America. More effective mitigation efforts may require expansion of the available toolkit to include new methods that provide earlier antemortem detection, higher throughput, and less expense than current immunohistochemistry (IHC) methods. The rectal mucosa near the rectoanal junction is a site of early accumulation of CWD prions and is safely sampled in living animals by pinch biopsy. A fluorescence-based, 96-well format, protein-aggregation assay-the real-time quaking-induced conversion (RT-QuIC) assay-is capable of ultra-sensitive detection of CWD prions. Notably, the recombinant protein substrate is crucial to the assay's performance and is now commercially available. In this blinded independent study, the preclinical diagnostic performance of a standardized RT-QuIC protocol using a commercially sourced substrate (MNPROtein) and a laboratory-produced substrate was studied using mock biopsy samples of the rectal mucosa from 284 white-tailed deer (Odocoileus virginianus). The samples were from a frozen archive of intact rectoanal junctions collected at depopulations of farmed herds positive for CWD in the United States. All deer were pre-clinical at the time of depopulation and infection status was established from the regulatory record, which evaluated the medial retropharyngeal lymph nodes (MRPLNs) and obex by CWD-IHC. A pre-analytic sample precipitation step was found to enhance the protocol's detection limit. Performance metrics were influenced by the choice of RT-QuIC diagnostic cut points (minimum number of positive wells and assay time) and by deer attributes (preclinical infection stage and prion protein genotype). The peak overall diagnostic sensitivities of the protocol were similar for both substrates (MNPROtein, 76.8%; laboratory-produced, 73.2%), though each was achieved at different cut points. Preclinical infection stage and prion protein genotype at codon 96 (G = glycine, S = serine) were primary predictors of sensitivity. The diagnostic sensitivities in late preclinical infections (CWD-IHC positive MPRLNs and obex) were similar, ranging from 96% in GG96 deer to 80% in xS96 deer (x = G or S). In early preclinical infections (CWD-IHC positive MRPLNs only), the diagnostic sensitivity was 64-71% in GG96 deer but only 25% in xS96 deer. These results demonstrate that this standardized RT-QuIC protocol for rectal biopsy samples using a commercial source of substrate produced stratified diagnostic sensitivities similar to or greater than those reported for CWD-IHC but in less than 30 hours of assay time and in a 96-well format. Notably, the RT-QuIC protocol used herein represents a standardization of protocols from several previous studies. Alignment of the sensitivities across these studies suggests the diagnostic performance of the assay is robust given quality reagents, optimized diagnostic criteria, and experienced staff.

Clinical characteristics of patients with gastroesophageal reflux disease against type 2 diabetes mellitus, depending on the presence of obesity

Objective — to reveal the features of the clinical course in patients with gastroesophageal reflux disease (GERD) depending on anthropometric indicators against the background of type 2 diabetes mellitus (DM2).
 Materials and methods. The study involved 100 patients, who were divided into 3 groups: group 1 consisted of 60 patients with DM2 in combination with GERD, group 2 included 20 patients with isolated GERD, and group 3 included DM2 patients. The patients of group 1 were additionally divided into 2 subgroups: 27 subjects with normal weight and 33 subjects with excessive body weight (EBW) or obesity of various degrees. The control group consisted of 20 practically healthy people. The distribution of patients by gender and age was carried out in accordance with the standards of the international classification of age periods of the World Health Organization, revised in 2015. From the total number of patients, 44 (44%) were men and 56 (56%) were women. Body mass index (BMI) was calculated according to the Quetelet formula. Endoscopic examination of the upper part of the gastrointestinal tract with targeted biopsy was performed with an esophagogastroduodenoscope with end optics «Olympus GIF Q 150­03» (manufacturer Olympus Europa SE & CO. KG, Japan). To increase the diagnostic value of esophagogastroduodenoscopy, methods of chromoscopy and pinch biopsy of the esophageal mucosa were used.
 Results. Comparison of GERD manifestations with account of anthropometric data revealed significant differences in the subgroups with normal weight and obesity (p <0.05). Gastroenterological complaints were not registered in 6 (26.1%) patients of the obesity subgroup (DM2 + GERD + obesity) and 8 (21.6%) patients of the non‑obese subgroup (DM2 + GERD). In the subgroup with obesity (DM2 + GERD + obesity), the significant differences (p <0.001) were detected in heartburn depending on the obesity stage. Heartburn in this subgroup occurred 7.4 times more often than in patients with normal weight compared to the subgroup without obesity (odds ratio 89.13% (95%CI 12.83—137.77) χ2=35.06; р <0.0001). Cardiac symptoms in patients with increased body weight were revealed 12.3 times more often vs. subjects with BMI less than 25 kg/m2 (odds ratio 5.0 (95% CI 1.58 ‑14.10); χ2=6.95; р=0.008).
 The presence of heartburn complaints at the 2nd stage of obesity (39±5 kg/m2) and its absence at normal body mass (28±2 kg/m2), p <0.001) have been established. Analysis of the dependence of the Helicobacter pylori contamination degree on the BMI value showed no statistically significant differences between the subgroups with normal body weight and subgroup with EBW and obesity. The highest contamination degree was found in group 1 (DM2 + GERD) with the same number of positive results in both subgroups, with and without obesity.
 Conclusions. It has been established that excessive body weight and obesity significantly affect the development and progression of gastroenterological complaints in patients with DM2 combined with GERD. The heartburn was more often registered in patients with DM2 with obesity, than in those with normal weight. Comparison of GERD findings with anthropometric data revealed significant differences between the subgroups with normal body weight and obesity (р <0.05). Heartburn in the obesity subgroup occurred 7.4 times more often.

Quantification of drug metabolising enzymes and transporter proteins in the paediatric duodenum via LC-MS/MS proteomics using a QconCAT technique

Characterising the small intestine absorptive membrane is essential to enable prediction of the systemic exposure of oral formulations. In particular, the ontogeny of key intestinal Drug Metabolising Enzymes and Transporter (DMET) proteins involved in drug disposition needs to be elucidated to allow for accurate prediction of the PK profile of drugs in the paediatric cohort.Using pinch biopsies from the paediatric duodenum (n = 36; aged 11 months to 15 years), the abundance of 21 DMET proteins and two enterocyte markers were quantified via LC-MS/MS. An established LCMS nanoflow method was translated to enable analysis on a microflow LC system, and a new stable-isotope-labelled QconCAT standard developed to enable quantification of these proteins. Villin-1 was used to standardise abundancy values. The observed abundancies and ontogeny profiles, agreed with adult LC-MS/MS-based data, and historic paediatric data obtained via western blotting. A linear trend with age was observed for duodenal CYP3A4 and CES2 only. As this work quantified peptides on a pinch biopsy coupled with a microflow method, future studies using a wider population range are very feasible. Furthermore, this DMET ontogeny data can be used to inform paediatric PBPK modelling and to enhance the understanding of oral drug absorption and gut bioavailability in paediatric populations.

P104 Exploring the transcriptomic miRNA signatures of Egyptian Inflammatory Bowel Disease patients

Abstract Background Inflammatory Bowel Disease (IBD) is a chronic autoimmune gastrointestinal disease, sub-classified into Crohn’s disease (CD) and ulcerative colitis (UC). The two subclasses are characterized by a relapsing-remitting course with an increasingly high incidence and prevalence worldwide. Molecular mechanisms guarding the pathogenesis of these diseases remain, to the present day, ambiguous to researchers. MicroRNAs are 22 nucleotides long small noncoding RNAs that have been recently described as essential participants in immune cell development and the immune response to pathogens. During the past decade, genetic and epigenetic studies in IBD have been labeled as essential; since endoscopic assessment and biopsies provide limited data concerning early disease activity, factors for relapse, and response to treatment. To the best of our knowledge, IBD research has never addressed miRNA profiles in Egyptian CD and UC patients as compared to unaffected controls. Methods Therefore, this study aims to profile miRNAs in Egyptian patients suffering from UC and CD, using RNA-seq of total RNA extracted from colonoscopically obtained tissue pinch biopsies. Results The sequencing results showed that 30 miRNAs were uniquely expressed in tissue biopsies obtained from the CD patients, as compared to only 14 uniquely expressed in UC patients. Further web-based functional enrichment analysis showed that the miRNAs- in both disease groups- are mainly involved in six interlinked molecular pathways; including the JAK/STAT, WNT, PI3K/AKT, FOXO, MAPK, and NF-κB signaling pathways. One of the most interesting findings of the current study is the fact that the downregulation of the miR-204-5p in UC patients (log2 FC= 5.05)-as compared to CD patients- may be caused by the sponging effect of the MALAT1 long non-coding RNA (lncRNA); affecting related signaling pathways such as the Wnt/β-catenin signaling. This suggests an essential interplay between miRNAs and lncRNAs in shaping the molecular pathogenesis of UC vs. CD. Conclusion The results of the current study revealed explicit-previously undetermined- differences in the miRNA profiles of patients suffering from UC and CD. Such results are expected to impact the understanding of the difference in the molecular pathogenesis of IBD subtypes affecting patients’ response to treatment.

Differential invasiveness & expression of antimicrobial peptides in Shigella serotypes.

The study of Shigella pathogenesis at present is severely hampered by the lack of a relevant animal model that replicates human bacillary dysentery. Different Shigella serogroups cause varying severity of clinical illness. Ex vivo colonization of Shigella flexneri, S. dysenteriae and S. sonnei were characterized in human paediatric colonic pinch biopsies in the in vitro organ culture (IVOC) model to study the invasiveness of Shigella by gentamicin protection assay (GPA). Furthermore, the expression of antimicrobial peptides (AMPs) in response to different serotypes of Shigella was also studied in IVOC model. IVOC explants were inoculated with 109 colony forming units of different serotypes of Shigella and recovery of bacteria studied. Histopathological analysis was carried out to study inflammatory immune responses. GPA was done to elucidate the invasiveness of different serotypes of Shigella. Secretions of AMPs were measured by enzyme-linked immunosorbent assay (ELISA). Western blotting was performed to check the expression of AMPs and nuclear factor kappa B in IVOC explants. After 24 h post-infection, the colon biopsies showed intense inflammatory reaction. In both IVOC and GPA, S. dysenteriae 1 was the most invasive as compared to S. flexneri and S. sonnei. S. sonnei was the least invasive. ELISA demonstrated that S. sonnei dampened the HBD (human β-defensin)-2 responses whereas there was augmentation by S. dysenteriae and there was a modest but non-significant increase by S. flexneri. A modest increase in HBD-3 by S. sonnei and S. flexneri was observed but was not found to be significant. However, western blotting data showed upregulation of all AMPs by all serotypes. Western blotting is more sensitive than ELISA. In the present study, differences in invasiveness and AMP production induced by different serotypes of Shigella were found. Human intestinal IVOC represents a model system to investigate early interaction between pathogenic bacteria and the human gut.

Dietary and management factors influence the equine gastric microbiome.

The purpose of this study was to characterize the relationship of diet and management factors with the glandular gastric mucosal microbiome. We hypothesize that the gastric mucosal microbial community is influenced by diet and management factors. Our specific objective is to characterize the gastric mucosal microbiome in relation to these factors. 57 client-owned horses in the southern Louisiana region with and without equine glandular gastric disease. Diet and management data were collected via a questionnaire. Gastroscopy was used for evaluation of equine gastric ulcer syndrome and collection of glandular mucosal pinch biopsies. 16S rRNA amplicon sequencing was used for microbiome analysis. Similarity and diversity indices and sequence read counts of individual taxa were compared between diet and management factors. Differences were detected in association with offering hay, type of hay, sweet feed, turnout, and stalling. Offering hay and stalling showed differences in similarity indices, whereas hay type, sweet feed, and turnout showed differences in similarity and diversity indices. Offering hay, hay type, and sweet feed were also associated with differences in individual sequence read counts. This study provides preliminary characterization of the complex relationship between the glandular gastric microbiome and diet/management factors. The ideal microbiome to promote a healthy glandular gastric environment remains unknown.

230. ENDOSCOPIC REFERENCE SCORE REMODELING SUBSCORE AND ESOPHAGEAL EOSINOPHIL COUNT DO NOT CORRELATE IN PLACEBO-TREATED EOSINOPHILIC ESOPHAGITIS PATIENTS FROM DUPILUMAB STUDIES

Abstract Although eosinophils are the hallmark of eosinophilic esophagitis (EoE) with threshold levels required for diagnosis, their exact role in EoE is unclear. The EoE-Endoscopic Reference Score (EREFS) assesses endoscopic inflammatory (edema/exudate/furrows) and remodeling (rings/strictures) features. We assessed the correlations between peak esophageal intraepithelial eosinophil count (eos/high-power field [hpf]) and EREFS in placebo-treated EoE patients from two clinical trials: phase 2 proof-of-concept (POC; NCT02379052; n = 24) and part A of phase 3 TREET (Phase3-PartA; NCT03633617; n = 39). POC was a 12-week trial in adults and Phase3-PartA was a 24-week trial in adults and adolescents. Endoscopic examination of the esophagus was performed at baseline (BL) and end of treatment (EOT) and scored for inflammatory and remodeling subscores and total score using EREFS (higher scores indicate greater severity). Peak eos/hpf was measured from pinch biopsies of proximal, mid, and distal esophagus at BL and EOT. Pearson correlations were performed between total/proximal/mid/distal eos/hpf and EREFS total, subscores, and components at BL, EOT, and for change from BL at EOT. Some strong correlations (r > 0.5) were observed between total peak eos/hpf and EREFS at BL in both studies and at EOT in Phase3-Part A (Table). Moderate-to-strong correlations (r > 0.3) were observed between total peak eos/hpf and EREFS inflammation subscore and edema/exudates/furrows individual components (some P > 0.5) in both studies. Correlations of total peak eos/hpf with EREFS remodeling subscore and rings/stricture components were not significant (P = 0.07–0.94). Peak eos/hpf in the proximal, mid, or distal esophagus were more strongly associated with EREFS inflammation subscore (majority moderate-to-strong correlations; P = 0.001–0.66) than EREFS remodeling subscore (weak correlations, P = 0.22–0.99) at BL/EOT for both studies. In these EoE patients, moderate-to-strong correlations were observed between eos/hpf and endoscopic markers of inflammation. No strong correlations were observed between total, proximal, mid, or distal peak eos/hpf and endoscopic parameters of remodeling. These data support a role for intact eosinophils in inflammatory changes in the esophagus in EoE and demonstrate the need for both histology and endoscopic evaluation. Further study, with larger sample sizes, is required to verify these findings in other contexts.

To investigate outcomes in endoscopic management of early oesophageal adenocarcinoma in Barrett oesophagus: experience at three Australian tertiary centres.

Barrett oesophagus is a known precursor of oesophageal adenocarcinoma (EAC). Early EAC includes T1a (invasion into mucosa) and T1b (invasion into submucosa but not muscularis propria). Endoscopic mucosal resection (EMR) provides accurate histological staging and definitive treatment for early EAC. Post EMR, the remaining Barrett is eradicated with radiofrequency ablation (RFA). However, there is a paucity of long-term Australian data. To investigate the efficacy and long-term outcomes of EMR and RFA in the management of early EAC. Retrospective analysis of patients early EAC treated endoscopically at three Western Australian tertiary centres, with at least 12-months follow up, over the past 10 years. Sixty-seven patients with early EAC (61 T1a and 6 T1b) were treated with EMR. Complete Barrett eradication was done by EMR in 31 of 67 patients whereas 36/67 patients underwent RFA for residual Barrett. EMR changed pinch biopsy histology from HGD (n = 33), HGD suspicious for IMC (n = 5) and LGD (n = 1) to early EAC in 58.2% (n = 39) patients. During a mean follow up of 37.2 months (interquartile range: 20, 56), complete remission of dysplasia and intestinal metaplasia was seen in 97% (n = 65) and 89.5% (n = 60) patients. One patient with T1b EAC underwent oesophagectomy. No cases developed metachronous EAC, progression to invasive adenocarcinoma or development of nodal/distant metastasis. Complications were endoscopically treated haematemesis (n = 1) and strictures (n = 16) requiring dilatations. Three patients died due to causes unrelated to IMC. EMR in conjunction with RFA is an effective and safe management for early EAC. EMR provides accurate staging and has low complication rates.

Significance of granulomas in the outcomes of Crohn's disease patients.

BackgroundThe presence of granulomas in the gastrointestinal (GI) tract is one of the characteristic histologic features of Crohn’s disease (CD). The clinical significance of granulomas remains unclear. In this study, we aimed to determine whether the presence of granulomas on endoscopic pinch biopsy or surgical resection from the upper or lower GI tract is associated with worse outcomes among patients with CD.MethodsThis was a retrospective chart review of patients with CD evaluated at a tertiary care center between 1996 and 2019. Patients were divided into 2 groups based on the presence or absence of granulomas on GI histology. Clinical and laboratory data, and outcomes of interest, were obtained from the electronic medical records. Patients’ characteristics and outcomes were compared between the 2 groups.ResultsA total of 237 patients were included in our study; 41 (17.3%) had granulomas on their biopsy/resection specimen. The presence of granulomas in the GI tract was significantly associated with the development of intra-abdominal abscesses and/or fistulas (P=0.037), greater utilization of immunomodulators (P=0.029), and greater use of immunosuppressive medications (immunomodulator and/or biologic therapy) (P=0.015). No significant differences were found between the 2 groups in terms of number of hospitalizations, presence of perianal disease, intestinal resection, mean age, mean age at initial diagnosis of CD, duration of disease, sex, or smoking history.ConclusionsThe presence of granulomas in the GI tract of CD patients may serve as a prognostic biomarker of worse disease severity. Larger studies are needed to better validate this finding.

S1643 Biliary Pinch Biopsies in the Diagnosis of IgG4 Cholangiopathy

S1643 Biliary Pinch Biopsies in the Diagnosis of IgG4 Cholangiopathy

S381 Esophageal Eosinophil Count Does Not Correlate With the Endoscopic Reference Score Remodeling Subscore in Placebo-Treated Eosinophilic Esophagitis Patients in the Phase 2 Proof-of-Concept and Phase 3 TREET Studies

Introduction: Eosinophilic esophagitis (EoE) is a chronic type 2 inflammatory disease of the esophagus. Although eosinophils (eos) are the hallmark of EoE diagnosis, their exact role in disease is unclear. The EoE-Endoscopic Reference Score (EREFS) assesses severity of endoscopically identified inflammatory (edema, exudate, furrows) and remodeling (rings, strictures) aspects of disease activity. To examine the relationship between eosinophilic inflammation and endoscopic disease activity, correlations were assessed between esophageal intraepithelial eos count (eos/high-power field [hpf]) and EREFS in EoE patients (pts) receiving placebo (PBO) in 2 clinical trials: the 12-week phase 2 proof-of-concept study (POC; NCT02379052) in adults and the 24-week Part A of the 3-part, phase 3 TREET study (P3PA; NCT03633617), in adolescents and adults. Methods: Endoscopies of the proximal and distal esophagus were performed at baseline (BL) and end of treatment (EOT) and scored for inflammatory and remodeling subscores, and total score using EREFS (higher scores indicate greater severity). Eos/hpf was measured from pinch biopsies of proximal, mid, and distal esophagus at BL and EOT. Pearson correlations were performed between eos/hpf and EREFS total, subscores, and components at BL, EOT, and change from BL at EOT. Results: Few strong correlations (correlation coefficient > 0.5) were observed at BL between eos/hpf and EREFS in pts receiving PBO of both studies (Table 1). Moderate-to-strong correlations were observed between EREFS total score and eos/hpf in P3PA, but not POC. Moderate-to-strong correlations were observed in both studies between eos/hpf and the EREFS inflammation subscore and inflammatory components of edema, exudates, and furrows (some of which reached statistical significance). All correlations of eosinophil levels to the EREFS remodeling subscore and rings/stricture components were weak-to-moderate and not statistically significant (P values ranged from 0.07 to 0.94). Conclusion: In these EoE pts, no strong correlations were observed between eos/hpf and endoscopic remodeling as assessed by EREFS. Moderate to strong correlations were observed between eos/hpf and endoscopic markers of inflammation. Combined with histology, endoscopic assessment of remodeling aspects of EoE provides a more comprehensive characterization of disease activity. Further study, with larger sample sizes, is required to verify and validate these findings in other populations, duration of observation, and treatment contexts.Table 1.: Correlations between esophageal intraepithelial eosinophil count (eos/hpf) and EREFS total score, inflammation and remodeling subscores, and individual components scores in patients with EoE receiving placebo in the phase 2 POC study and part A of the phase 3 LIBERTY TREET study.

Gastric microbiome in horses with and without equine glandular gastric disease.

BackgroundThe role of the gastric microbiome in development or persistence of equine glandular gastric disease (EGGD) remains to be investigated.Hypothesis/ObjectivesThe objective was to characterize the glandular mucosal and gastric fluid microbiomes of horses with and without EGGD. It was hypothesized that differences in the mucosal microbiome are associated with EGGD.AnimalsTwenty‐four horses were enrolled.MethodsGastroscopy was performed and EGGD scores recorded (score 0, n = 6; score 1, n = 8; score ≥2, n = 10). Gastric fluid and pinch biopsies of healthy glandular mucosa and EGGD lesions were collected via gastroscope. 16S rRNA amplicon sequencing of the gastric fluid and glandular mucosal biopsies was performed. Relationships between gastric fluid and mucosal microbial community composition were evaluated among EGGD score groups (EGGD 0‐BX, EGGD 1‐BX, EGGD ≥2‐BX) and among endoscopic appearances: controls from horses without EGGD and normal areas, hyperemic areas, and lesions from horses with EGGD.ResultsMicrobial community structure of mucosal biopsies differed among EGGD score groups (Jaccard similarity index; P = .009). Principal coordinate analysis showed separate clusters for EGGD 0‐BX and EGGD ≥2‐BX.Conclusions and Clinical ImportanceA modest difference was detected in the community structure of the gastric glandular mucosal microbiome in association with EGGD score.

Histologic Study of the Esophagogastric Junction of Organ Donors Reveals Novel Glandular Structures in Normal Esophageal and Gastric Mucosae.

INTRODUCTION:Whether cardiac mucosa at the esophagogastric junction is normal or metaplastic is controversial. Studies attempting to resolve this issue have been limited by the use of superficial pinch biopsies, abnormal esophagi resected typically because of cancer, or autopsy specimens in which tissue autolysis in the stomach obscures histologic findings.METHODS:We performed histologic and immunohistochemical studies of the freshly fixed esophagus and stomach resected from 7 heart-beating, deceased organ donors with no history of esophageal or gastric disease and with minimal or no histologic evidence of esophagitis and gastritis.RESULTS:All subjects had cardiac mucosa, consisting of a mixture of mucous and oxyntic glands with surface foveolar epithelium, at the esophagogastric junction. All also had unique structures we termed compact mucous glands (CMG), which were histologically and immunohistochemically identical to the mucous glands of cardiac mucosa, under esophageal squamous epithelium and, hitherto undescribed, in uninflamed oxyntic mucosa throughout the gastric fundus.DISCUSSION:These findings support cardiac mucosa as a normal anatomic structure and do not support the hypothesis that cardiac mucosa is always metaplastic. However, they do support our novel hypothesis that in the setting of reflux esophagitis, reflux-induced damage to squamous epithelium exposes underlying CMG (which are likely more resistant to acid-peptic damage than squamous epithelium), and proliferation of these CMG as part of a wound-healing process to repair the acid-peptic damage could result in their expansion to the mucosal surface to be recognized as cardiac mucosa of a columnar-lined esophagus.

Multi 'Omics Analysis of Intestinal Tissue in Ankylosing Spondylitis Identifies Alterations in the Tryptophan Metabolism Pathway.

Intestinal microbial dysbiosis, intestinal inflammation, and Th17 immunity are all linked to the pathophysiology of spondyloarthritis (SpA); however, the mechanisms linking them remain unknown. One potential hypothesis suggests that the dysbiotic gut microbiome as a whole produces metabolites that influence human immune cells. To identify potential disease-relevant, microbiome-produced metabolites, we performed metabolomics screening and shotgun metagenomics on paired colon biopsies and fecal samples, respectively, from subjects with axial SpA (axSpA, N=21), Crohn’s disease (CD, N=27), and Crohn’s-axSpA overlap (CD-axSpA, N=12), as well as controls (HC, N=24). Using LC-MS based metabolomics of 4 non-inflamed pinch biopsies of the distal colon from subjects, we identified significant alterations in tryptophan pathway metabolites, including an expansion of indole-3-acetate (IAA) in axSpA and CD-axSpA compared to HC and CD and indole-3-acetaldehyde (I3Ald) in axSpA and CD-axSpA but not CD compared to HC, suggesting possible specificity to the development of axSpA. We then performed shotgun metagenomics of fecal samples to characterize gut microbial dysbiosis across these disease states. In spite of no significant differences in alpha-diversity among the 4 groups, our results confirmed differences in gene abundances of numerous enzymes involved in tryptophan metabolism. Specifically, gene abundance of indolepyruvate decarboxylase, which generates IAA and I3Ald, was significantly elevated in individuals with axSpA while gene abundances in HC demonstrated a propensity towards tryptophan synthesis. Such genetic changes were not observed in CD, again suggesting disease specificity for axSpA. Given the emerging role of tryptophan and its metabolites in immune function, altogether these data indicate that tryptophan metabolism into I3Ald and then IAA is one mechanism by which the gut microbiome potentially influences the development of axSpA.

Performing Colonoscopic-Guided Pinch Biopsies in Mice and Evaluating Subsequent Tissue Changes

Performing Colonoscopic-Guided Pinch Biopsies in Mice and Evaluating Subsequent Tissue Changes

Pinch biopsy: A modified punch biopsy technique to avoid histological artifacts and surgical tools.

Pinch biopsy: A modified punch biopsy technique to avoid histological artifacts and surgical tools.