Basal Zone Hyperplasia Research Articles

Tissue-specific inducible IL-33 expression elicits features of eosinophilic esophagitis

BackgroundIL-33 is a type 2 inflammatory cytokine that is elevated in the esophageal epithelium of EoE subjects. We previously developed a mouse model of EoE dependent on constitutive overexpression of IL-33 from the esophageal epithelium (EoE33). ObjectiveOur objective was to develop an inducible, IL-33-dependent model of EoE and examine induction of EoE-associated pathology. MethodsWe utilized a tetracycline-inducible system to express IL-33 in the esophagus by generating two transgenic mice. The first (iSophagus) expresses a reverse tetracycline transactivator (rtTA) from the esophageal epithelium. The second (TRE33) features a tetracycline-response element driving expression of IL-33. When crossed, these mice generate an inducible model of EoE (iEoE33). Mice were administered doxycycline-infused chow for up to 2 weeks. Cytokines were assessed by ELISA or bead-based multiplex. T cells were assessed by flow cytometry. Pathology was assessed by histology and immunohistochemistry for IL-33, eosinophil peroxidase, CD4, and Ki-67. iEoE33 was treated with steroids and crossed with IL-13-/- mice. For detailed Methods, please see the Methods section in this article's Online Repository at www.jacionline.org. ResultsDoxycycline-treated iEoE33 mice demonstrated expression of IL-33 in the esophageal epithelium, and esophageal pathology including eosinophilia, CD4+ cell infiltrate, basal zone hyperplasia, and dilated intercellular spaces. These findings became pronounced on day 7 of induction, were accompanied by weight loss and esophageal thickening, and were steroid responsive and IL-13 dependent. ConclusionInducible IL-33 expression in the esophageal epithelium elicited features pathognomonic of EoE. iEoE33 enables investigation of EoE disease mechanisms as well as initiation, progression, and resolution.

Machine learning–based identification and characterization of mast cells in eosinophilic esophagitis

BackgroundEosinophilic esophagitis (EoE) is diagnosed and monitored using esophageal eosinophil levels; however, EoE also exhibits a marked, understudied esophageal mastocytosis. ObjectiveUsing machine learning, we localized and characterized esophageal mast cells to decipher their potential role in disease pathology. MethodsEsophageal biopsy samples (EoE, control) were stained for mast cells by anti-tryptase and imaged using immunofluorescence; high-resolution whole tissue images were digitally assembled. Machine learning software was trained to identify, enumerate, and characterize mast cells, designated Mast Cell-Artificial Intelligence (MC-AI). ResultsMC-AI enumerated cell counts with high accuracy. During active EoE, epithelial mast cells increased and lamina propria (LP) mast cells decreased. In controls and EoE remission patients, papillae had the highest mast cell density and negatively correlated with epithelial mast cell density. Mast cell density in the epithelium and papillae correlated with the degree of epithelial eosinophilic inflammation, basal zone hyperplasia, and LP fibrosis. MC-AI detected greater mast cell degranulation in the epithelium, papillae, and LP in EoE patients compared with control individuals. Mast cells were localized further from the basement membrane in active EoE than EoE remission and control individuals but were closer than eosinophils to the basement membrane in active EoE. ConclusionUsing MC-AI, we identified a distinct population of homeostatic esophageal papillae mast cells; during active EoE, this population decreases, undergoes degranulation, negatively correlates with epithelial mast cell levels, and significantly correlates with distinct histologic features. Overall, MC-AI provides a means to understand the potential involvement of mast cells in EoE and other disorders.

A218 TRADING ONE PROBLEM FOR ANOTHER? THE EMERGENCE OF LYMPHOCYTIC ESOPHAGITIS IN A PEDIATRIC PATIENT WITH EOSINOPHILIC ESOPHAGITIS AFTER TREATMENT WITH DUPILUMAB

Abstract Background Eosinophilic esophagitis (EoE) is a Th2 driven chronic, inflammatory disorder defined by esophageal dysfunction and a peak eosinophil count (PEC) ≧ 15 eosinophils/high-power field on biopsy. Dupilumab, a human monoclonal antibody that inhibits IL-4 and IL-13 signaling was recently approved for use in Canada in children with EoE. There is limited data on the histologic abnormalities found with reintroduction of dietary triggers on dupilumab. Aims To describe emergence of lymphocytic esophagitis without eosinophilia observed during food reintroduction in a pediatric patient with EoE on dupilumab. Methods Case report and literature review. Results We present a 14-year-old boy with extensive food allergies, eczema, asthma and treatment refractory EoE. After failing to improve with proton-pump inhibitor (PPI), food elimination diet and topical steroids, he was started on an elemental formula with concomitant PPI. This resulted in symptomatic and histologic remission, however food restriction led to poor quality of life. The patient was started on dupilumab 200 mg every 2 weeks and had a dramatic improvement in his disease course. Over 2 years on treatment, several allergic foods were reintroduced with normal histologic biopsies. However, two dietary challenges led to the emergence of lymphocytic esophagitis with basal zone hyperplasia (BZH) and dilated intercellular spaces (DIS), but no eosinophilia. Subsequent removal of the dietary antigen and endoscopic reassessment led to normal biopsies, without lymphocytic or eosinophilic infiltration. Lymphocytic esophagitis is rare in children and the etiology is unknown; it is characterized by increased intraepithelial lymphocytes without eosinophils or neutrophils, and associated spongiosis. The emergence of lymphocytic esophagitis was unexpected and subsequent normalization of histology with removal of an antigen suggests that the lymphocytic pattern observed was driven by the allergic food. This may indicate that IL-4/IL-13 antagonism by dupilumab affects other immune signaling pathways, resulting in a lymphocytic-predominant inflammatory response upon exposure to allergic food antigens. Conclusions Dupilumab is a promising new medication in the management of pediatric EoE, particularly in the extremely atopic patient. In our case, the use of dupilumab led to improved antigen tolerance and quality of life. However, the emergence of lymphocytic esophagitis was unexpected, and the natural history and prognosis of this condition is not well defined. This is the first case to describe the emergence of lymphocytic esophagitis in a patient treated for eosinophilic esophagitis with dupilumab, and its subsequent resolution with dietary exclusion. Funding Agencies None

Epithelial overexpression of IL-33 induces eosinophilic esophagitis dependent on IL-13

BackgroundEosinophilic esophagitis (EoE) is an increasingly common inflammatory condition of the esophagus; however, the underlying immunologic mechanisms remain poorly understood. The epithelium-derived cytokine IL-33 is associated with type 2 immune responses and elevated in esophageal biopsies from EoE subjects. ObjectiveWe hypothesized that overexpression of IL-33 by the esophageal epithelium would promote the immunopathology of EoE. MethodsWe evaluated the functional consequences of esophageal epithelial overexpression of a secreted and active form of IL-33 (saIL-33) in a novel transgenic mouse, EoE33. EoE33 mice were analyzed for clinical and immunologic phenotypes. Esophageal contractility was assessed. Epithelial cytokine responses were analyzed in three-dimensional organoids. EoE33 phenotypes were further characterized in ST2-/-, eosinophil-deficient, and IL-13-/- mice. Finally, EoE33 mice were treated with dexamethasone. ResultsEoE33 mice displayed ST2-dependent, EoE-like pathology and failed to thrive. Esophageal tissue remodeling and inflammation included basal zone hyperplasia, eosinophilia, mast cells, and Th2 cells. Marked increases in levels of type 2 cytokines, including IL-13, and molecules associated with immune responses and tissue remodeling were observed. Esophageal organoids suggested reactive epithelial changes. Genetic deletion of IL-13 in EoE33 mice abrogated pathological changes in vivo. EoE33 mice were steroid responsive. ConclusionIL-33 overexpression by the esophageal epithelium generated immunopathology and clinical phenotypes resembling human EoE. IL-33 may play a pivotal role in the etiology of EoE by activating the IL-13 pathway. EoE33 mice are a robust experimental platform for mechanistic investigation and translational discovery.

The minichromosome maintenance complex drives esophageal basal zone hyperplasia.

Eosinophilic esophagitis (EoE) is a chronic gastrointestinal disorder characterized by food antigen-driven eosinophilic inflammation and hyperproliferation of esophageal mucosa. By utilizing a large-scale, proteomic screen of esophageal biopsies, we aimed to uncover molecular drivers of the disease. Proteomic analysis by liquid chromatography-tandem mass spectrometry identified 402 differentially expressed proteins (DEPs) that correlated with the EoE transcriptome. Immune cell-related proteins were among the most highly upregulated DEPs in EoE compared with controls, whereas proteins linked to epithelial differentiation were primarily downregulated. Notably, in the inflamed esophageal tissue, all 6 subunits of the minichromosome maintenance (MCM) complex, a DNA helicase essential for genomic DNA replication, were significantly upregulated at the gene and protein levels. Furthermore, treating esophageal epithelial cells with a known inhibitor of the MCM complex (ciprofloxacin) blocked esophageal epithelial proliferation. In a murine model of EoE driven by overexpression of IL-13, ciprofloxacin treatment decreased basal zone thickness and reduced dilated intercellular spaces by blocking the transition of epithelial cells through the S-phase of the cell cycle. Collectively, a broad-spectrum proteomic screen has identified the involvement of the MCM complex in EoE and has highlighted MCM inhibitors as potential therapeutic agents for the disease.

262. DUPILUMAB REDUCED EOSINOPHIL COUNTS AND IMPROVED HISTOLOGY GRADE/STAGE SCORES IN PATIENTS WITH EOSINOPHILIC ESOPHAGITIS: LIBERTY EOE TREET RESULTS

Abstract Background In the 3-part, phase 3 LIBERTY EoE TREET study (NCT03633617) dupilumab 300 mg weekly (qw) demonstrated significant improvements in symptoms and eosinophil counts, and clinically meaningful improvement in endoscopic features vs placebo, in adults and adolescents with EoE. The objective of this analysis was to further assess the effect of dupilumab vs placebo on histologic aspects of disease in Parts A and B of LIBERTY EoE TREET. Methods Patients aged ≥12 years were randomized 1:1 to dupilumab 300 mg qw or placebo. Endpoints (at Week 24) were the proportion of patients achieving ≤1, ≤6, and < 15 eosinophils per high-power field (eos/hpf), change from baseline in peak eosinophil count and Histologic Scoring System (HSS) scores, specifically the severity (grade) and extent (stage) of abnormality of the 8 components (basal zone hyperplasia [BZH], eosinophil inflammation [EI], eosinophil abscess [EA], eosinophil surface layering [ESL], dilated intercellular spaces [DIS], surface epithelial alteration [SEA], dyskeratotic epithelial cells [DEC], and lamina propria fibrosis [LPF]). P-values are nominal unless otherwise specified. Results Dupilumab significantly increased the proportion of patients achieving ≤1, ≤6, and < 15 eos/hpf in Part A (P < 0.0001, P < 0.05, and P < 0.0001, respectively) and Part B (all P < 0.0001) vs placebo. Percent change in peak eosinophil count from baseline and HSS grade/stage scores were significantly improved with dupilumab vs placebo for Parts A and B (all P < 0.0001) (Table). Significant improvements were observed for the histologic components BZH, EI, EA, ESL, SEA grade/stage scores (P < 0.0001) in both Parts, DIS grade score in Part A (P < 0.05), and DEC grade/stage scores in Part B (P < 0.05); other components showed numeric improvements. Dupilumab was generally well tolerated. Conclusions Dupilumab 300 mg qw significantly decreased eosinophil counts and improved the severity and extent of histologic aspects of the disease as measured by HSS versus placebo in adults and adolescents with EoE up to 24 weeks, documenting a more global improvement in addition to eosinophil counts. Overall safety was consistent with the known dupilumab safety profile.

IL-13–induced STAT3-dependent signaling networks regulate esophageal epithelial proliferation in eosinophilic esophagitis

Basal zone hyperplasia (BZH) and dilated intercellular spaces (DISs) are thought to contribute to the clinical manifestations of eosinophilic esophagitis (EoE); however, the molecular pathways that drive BZH remain largely unexplored. We sought to define the role of IL-13-induced transcriptional programs in esophageal epithelial proliferation in EoE. We performed RNA sequencing, bioinformatics, Western blot, reverse transcriptase quantitative PCR, and histologic analyses on esophageal biopsies from healthy control and patients with EoE, primary esophageal cells derived from patients with EoE, and IL-13-stimulated esophageal epithelial keratinocytes grown at the air-liquid interface (EPC2-ALI). Genetic (shRNA) and pharmacologic (proteolysis-targeting chimera degrader) approaches and invivo model of IL-13-induced esophageal epithelial remodeling (Krt5-rtTA x tetO-IL-13Tg) were used to define the role of signal transducer and activator of transcription 3 (STAT3) and STAT6 and secreted frizzled-related protein 1 (SFRP1) in esophageal epithelial proliferation. RNA-sequencing analysis of esophageal biopsies (healthy control vs EoE) and EPC2-ALI revealed 82 common differentially expressed genes that were enriched for putative STAT3 target genes. Invitro and invivo analyses revealed a link between IL-13-induced STAT3 and STAT6 phosphorylation, SFRP1 mRNA expression, and esophageal epithelial proliferation. Invitro studies showed that IL-13-induced esophageal epithelial proliferation was STAT3-dependent and regulated by the STAT3 target SFRP1. SFRP1 mRNA is increased in esophageal biopsies from patients with active EoE compared with healthy controls or patients in remission and identifies an esophageal suprabasal epithelial cell subpopulation that uniquely expressed the core EoE proinflammatory transcriptome genes (CCL26, ALOX15, CAPN14, ANO1, and TNFAIP6). These studies identify SFRP1 as a key regulator of IL-13-induced and STAT3-dependent esophageal proliferation and BZH in EoE and link SFRP1+ esophageal epithelial cells with the proinflammatory and epithelial remodeling response in EoE.

Predictive Histologic Markers For Long-term Pediatric Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is a chronic esophageal type 2 inflammatory disease with ≥ 15 intraepithelial eosinophils per high power field (eos/HPF). There are no prognostic indicators for longitudinal disease response or disease progression. Persistent basal zone hyperplasia (BZH) following short-term therapy associates with endoscopic abnormalities and mast cell infiltration. We hypothesized that BZH might predict long-term EoE trajectory.

Клинико-морфологическая диагностика эозинофильного эзофагита

Eosinophilic esophagitis (EoE) is an immune-mediated disease that presents with dysphagia and esophageal bolus obstruction and is characterized by predominant intraepithelial eosinophilic infiltration at histology. The aim of our literature review was to delineate clinical and morphological EoE features in terms of differential diagnosis with other esophageal diseases, i.e., gastroesophageal reflux disease (GERD), inflammatory bowel diseases (IBDs), autoimmune diseases, and rare esophageal disorders. Clinical features of dysphagia and esophageal bolus obstruction and endoscopic criteria (according to EREFS) are typical of EoE. Nevertheless, eosinophilia of the esophageal mucosa is not a specific marker of mucosal injury and is not sufficient for EoE diagnosis. Therefore, eosinophilic esophagitis histological scoring system (EoEHSS) was developed. It involves assessment of intraepithelial eosinophilic infiltration, basal zone hyperplasia, eosinophilic abscesses, eosinophil surface layering, dilated intercellular spaces, surface epithelial alteration, dyskeratotic epithelial cells, and lamina propria fibrosis. Complex clinical, endoscopic, and histological evaluation allows accurate diagnosis of EoE and other causal factors of esophageal eosinophilia. Keywords: eosinophilic esophagitis, esophageal eosinophilia, gastroesophageal reflux disease, celiac disease, inflammatory bowel diseases, achalasia, atopy

Eozinofilni ezofagitis

Eosinophilic esophagitis (EoE) is an inflammatory disorder characterized by intraepithelial eosinophilic infiltration followed by esophageal dysfunction. Pathophysiological mechanism of EoE is still not well understood, with several factors that may contribute, such as host immunity, environmental and genetic factors. Modern diagnostic for EoE should include: esophageal dysfunction, esophageal biopsy with at least 15 eosinophils per high power field and absence of other pathology characterized by increased number of eosinophils. The most common presenting symptoms in adults are dysphagia, heartburn, food impaction and chest pain. Children are usually presented with nausea and vomiting, anorexia, heartburn, regurgitation, chest burn and abdominal pain. Endoscopically, patients with EoE are characterized by longitudinal furrows (vertical lines, darker than surrounding mucosa), esophageal trachealization (numerous transversal rings, as in trachea), exudate (white plaques), edema (decreased mucosal vascularization), strictures and crepe-paper mucosa (mucosal friability and tearing during endoscopy). Histological features of EoE could be separated into major and minor criteria. Major criteria include: intraepithelial infiltration by eosinophils (>15 eosinophils/HPF), eosinophilic microabscesses (≥4 eosinophils in a collection), eosinophils occupying outer layer of the squamous epithelium, epithelial sloughing and eosinophil degranulation. Minor criteria include: basal zone hyperplasia, lengthening of the epithelial papillae, intracellular edema and subepithelial fibrosis. In order to set adequate diagnosis, all other conditions related to increased number of eosinophils should be excluded. The most common and the most important differential is gastroesophageal reflux disease (GERD). Treatment of the EoE encompasses: proton pump inhibitors (PPI), corticosteroids (topical and systemic), elimination diet and esophageal dilation.

Harnessing artificial intelligence to infer novel spatial biomarkers for the diagnosis of eosinophilic esophagitis.

Eosinophilic esophagitis (EoE) is a chronic allergic inflammatory condition of the esophagus associated with elevated esophageal eosinophils. Second only to gastroesophageal reflux disease, EoE is one of the leading causes of chronic refractory dysphagia in adults and children. EoE is a clinicopathologic disorder and the histological portion of the diagnosis requires enumerating the density of esophageal eosinophils in esophageal biopsies, and evaluating additional features such as basal zone hyperplasia is helpful. However, this task requires time-consuming, somewhat subjective manual analysis, thus reducing the ability to process the complex tissue structure and infer its relationship with the patient's clinical status. Previous artificial intelligence (AI) approaches that aimed to improve histology-based diagnosis focused on recapitulating identification and quantification of the area of maximal eosinophil density, the gold standard manual metric for determining EoE disease activity. However, this metric does not account for the distribution of eosinophils or other histological features, over the whole slide image. Here, we developed an artificial intelligence platform that infers local and spatial biomarkers based on semantic segmentation of intact eosinophils and basal zone distributions. Besides the maximal density of eosinophils [referred to as Peak Eosinophil Count (PEC)] and a maximal basal zone fraction, we identify the value of two additional metrics that reflect the distribution of eosinophils and basal zone fractions. This approach enables a decision support system that predicts EoE activity and potentially classifies the histological severity of EoE patients. We utilized a cohort that includes 1,066 biopsy slides from 400 subjects to validate the system's performance and achieved a histological severity classification accuracy of 86.70%, sensitivity of 84.50%, and specificity of 90.09%. Our approach highlights the importance of systematically analyzing the distribution of biopsy features over the entire slide and paves the way toward a personalized decision support system that will assist not only in counting cells but can also potentially improve diagnosis and provide treatment prediction.

233. ENDOSCOPIC REFERENCE SCORE AND HISTOLOGICAL SCORING SYSTEM ARE COMPLEMENTARY ASSESSMENTS FOR CHARACTERIZING FIBROSTENOTIC OR INFLAMMATORY PHENOTYPES IN EOSINOPHILIC ESOPHAGITIS PATIENTS

Abstract The Histologic Scoring System (HSS) assesses severity/extent of histologic features (eosinophil density [ED]/basal zone hyperplasia [BZH]/eosinophil abscesses [EA]/eosinophil surface layering [SL]/surface epithelial alteration [SEA]/dyskeratotic epithelial cells [DEC]/dilated intercellular spaces [DIS]/lamina propria fibrosis [LPF]) in eosinophilic esophagitis (EoE). The Endoscopic Reference Score (EREFS) assesses endoscopic feature severity (edema/exudates/furrows/rings/strictures). We correlated HSS components with inflammatory/remodeling EREFS components in placebo-treated EoE patients from 2 trials—phase 2 proof-of-concept (POC; NCT02379052), phase 3 TREET part A (Phase3-PartA; NCT03633617). POC was a 12-week trial in adults, and Phase3-PartA was a 24-week trial in adults and adolescents. Proximal/mid/distal esophagus biopsies were collected at baseline/end of treatment (EOT) and scored by HSS for grade (severity)/stage (extent)/components (higher scores = greater severity). Endoscopies were scored by EREFS (higher scores = greater severity) and inflammatory (edema+exudates+furrows) and remodeling (rings+stricture) subscores calculated. Pearson correlation and single co-variate regression model analyses were performed between baseline HSS grade/stage, total/individual components scores and EREFS total/components scores and subscores, and for the change in scores from baseline at EOT (ΔEOT). Moderate-to-strong correlations (r > 0.3) were observed between total EREFS and HSS grade/stage for baseline/ΔEOT in POC and baseline in Phase3-PartA (Table). Moderate correlations were observed between BZH and EREFS remodeling subscore and rings for ΔEOT in Phase3-PartA; DIS grade and EREFS remodeling subscore and strictures for baseline and ΔEOT in POC but not Phase3-PartA; and EREFS inflammation and remodeling subscores and components for SEA and SL at baseline and ΔEOT in POC. Moderate-to-strong correlations were observed between EREFS inflammation subscore and DIS stage and between edema and DIS grade/stage at baseline in both studies. Similar results were observed using regression analyses. Specific components of HSS and EREFS, reflecting inflammatory and remodeling processes, are closely correlated, when examined by Pearson correlations or regression analyses, and can aid identification of fibrostenotic or inflammatory phenotypes in EoE. Correlations of DIS with endoscopic inflammatory and remodeling features reflect the role of barrier dysfunction in maintaining chronic inflammation that ultimately leads to remodeling.

Detergent exposure induces epithelial barrier dysfunction and eosinophilic inflammation in the esophagus.

Eosinophilic esophagitis (EoE) is a chronic allergic disease associated with type 2 inflammation and epithelial barrier dysfunction. The etiology is unknown, however, genetic heritability studies suggest environmental factors play a key role in pathogenesis. Detergents, such as sodium dodecyl sulfate (SDS), are common ingredients in household products such as dish soap and toothpaste. We hypothesized detergent exposure decreases epithelial barrier function and induces esophageal inflammation. Immortalized esophageal epithelial cells (EPC2) were cultured in air-liquid interface (ALI) and exposed to SDS. Barrier function/activity was assessed by transepithelial electrical resistance (TEER), FITC-dextran flux, and RT-PCR. Additionally, SDS-treated mouse esophageal organoids were evaluated for morphology. To investigate the effects of SDS in vivo, mice were treated with 0.5% SDS in drinking water for 14 days. Esophagi were assessed by gross morphology, histopathology, protein expression, and bulk RNA sequencing. When EPC2 cells were exposed to SDS (5μg/ml) for 96 h, TEER decreased (p=0.03), and FITC-dextran flux increased (p=0.0002). mRNA expression of IL-33 increased 4.5-fold (p=0.02) at 6h and DSG1 decreased (p < 0.0001) by 72 h. Disrupted epithelial integrity was noted in SDS-treated esophageal organoids. When mice were exposed to SDS, they showed increased esophageal width, chemokine, and metalloprotease levels. Mice treated with SDS also showed increased IL-33 protein expression, basal zone hyperplasia, CD4+ cell infiltration, and esophageal eosinophilia. RNA sequencing revealed upregulation of immune response pathway genes. Exposure to SDS decreases esophageal barrier integrity, stimulates IL-33 production, and promotes epithelial hyperplasia and tissue eosinophilia. Detergents may be a key environmental trigger in EoE pathogenesis.

Eosinophilic esophagitis: Immune mechanisms and therapeutic targets.

Eosinophilic esophagitis (EoE) is an emerging chronic inflammatory disease of the oesophagus and is clinically characterized by upper gastrointestinal (GI) symptoms including dysphagia and esophageal food impaction. Histopathologic manifestations, which include intraepithelial eosinophilic inflammation and alterations of the esophageal squamous epithelium, such as basal zone hyperplasia (BZH) and dilated intercellular spaces (DIS), are thought to contribute to esophageal dysfunction and disease symptoms. Corroborative clinical and discovery science-based studies have established that EoE is characterized by an underlying allergic inflammatory response, in part, related to the IL-13/CCL26/eosinophil axis driving dysregulation of several key epithelial barrier and proliferative regulatory genes including kallikrein (KLK) serine proteases, calpain 14 (CAPN14) and anoctamin 1 (ANO1). The contribution of these inflammatory and proliferative processes to the clinical and histological manifestations of disease are not fully elucidated. Herein, we discuss the immune molecules and cells that are thought to underlie the clinical and pathologic manifestations of EoE and the emerging therapeutics targeting these processes for the treatment of EoE.

Esophageal remodeling in eosinophilic esophagitis: Relationships to luminal captured biomarkers of inflammation and periostin

Esophageal remodeling is a factor in disease progression and symptom severity for patients with eosinophilic esophagitis (EoE). Remodeling can begin early in children, resulting in stricture and food impaction. Detection of esophageal remodeling often depends on endoscopy and is appreciated only in its later stages. We sought to determine whether luminal eosinophil-associated and remodeling proteins captured by the esophageal string test (EST) correlate with measures of esophageal remodeling and biomarkers of the epithelial-mesenchymal transition (EMT). Patients with EoE (7-18 years old) were enrolled from 2 pediatric hospitals. Participants performed the EST and underwent endoscopy. Histology, distensibility measured by endoluminal functional lumen imaging probe, and symptoms were assessed. Protein quantitation by ELISA was performed on mucosal biopsy and EST samples. Tissue sections were evaluated for EMT. Outcome measures were summarized, and Spearman ρ was used to assess bivariate correlations. Forty patients (68% male) were enrolled (mean age, 12.5 years). Twenty-four (60%) had active disease (≥15 eosinophils per high-power field). EST-captured eotaxin-3, major basic protein 1, EDN, eosinophil peroxidase, and Charcot-Leyden crystal protein/galectin-10 showed significant correlations with peak eosinophils per high-power field (ρ 0.53-0.68, P< .001). Luminal proteins positively correlated with endoscopic features and markers of EMT, and negatively with esophageal distensibility. Periostin was captured by the EST and correlated with eosinophil density, basal zone hyperplasia, endoscopic appearance, and markers of EMT. Luminal markers of esophageal remodeling in addition to biomarkers of eosinophilic inflammation correlate with epithelial and functional remodeling in EoE.

Application of the Eosinophilic Esophagitis Histology Scoring System Grade Scores in Patients at British Columbia Children’s Hospital

Introduction Histologic diagnosis of eosinophilic esophagitis (EoE) involves peak eosinophil counts (PEC) being greater than 15 per high power field. The EoE Histology Scoring System (EoEHSS) was developed to comprehensively evaluate biopsies to better predict symptom and endoscopy response; we aimed to validate the EoEHSS in our provincial registry, where EoEHSS had not been employed. Methods We reviewed 186 esophageal biopsies from 16 patients at diagnosis and follow-up. Statistical analyses were conducted to quantify how grade scores correlate with active EoE status and PEC counts, and each feature’s ability to predict active disease. Results Nearly all EoEHSS variables were associated with active EoE and high PEC, with basal zone hyperplasia, eosinophil abscesses, and surface epithelial alteration being most predictive in identifying active EoE. Conclusions We validated and demonstrated each EoEHSS variable’s strength in tracking traditional PEC counts, resulting in its adoption as a standard reporting element for our research registry.

Development and Validation of Web-Based Tool to Predict Lamina Propria Fibrosis in Eosinophilic Esophagitis.

Approximately half of esophageal biopsies from patients with eosinophilic esophagitis (EoE) contain inadequate lamina propria, making it impossible to determine the lamina propria fibrosis (LPF). This study aimed to develop and validate a web-based tool to predict LPF in esophageal biopsies with inadequate lamina propria. Prospectively collected demographic and clinical data and scores for 7 relevant EoE histology scoring system epithelial features from patients with EoE participating in the Consortium of Eosinophilic Gastrointestinal Disease Researchers observational study were used to build the models. Using the least absolute shrinkage and selection operator method, variables strongly associated with LPF were identified. Logistic regression was used to develop models to predict grade and stage of LPF. The grade model was validated using an independent data set. Of 284 patients in the discovery data set, median age (quartiles) was 16 (8-31) years, 68.7% were male patients, and 93.4% were White. Age of the patient, basal zone hyperplasia, dyskeratotic epithelial cells, and surface epithelial alteration were associated with presence of LPF. The area under the receiver operating characteristic curve for the grade model was 0.84 (95% confidence interval: 0.80-0.89) and for stage model was 0.79 (95% confidence interval: 0.74-0.84). Our grade model had 82% accuracy in predicting the presence of LPF in an external validation data set. We developed parsimonious models (grade and stage) to predict presence of LPF in esophageal biopsies with inadequate lamina propria and validated our grade model. Our predictive models can be easily used in the clinical setting to include LPF in clinical decisions and determine its effect on treatment outcomes.

Association of Incidental Positron Emission Tomography Uptake in the Esophagus to Gastroesophageal Reflux Disease

The Los Angeles (LA) classification is the most accurate means of assessing esophageal injury from caustic gastric acid with focused and greater concentrations in areas of erosive disease.¹ However, data from animal models and patients have proposed that an initial diffuse inflammatory pathway contributes to injury in gastroesophageal reflux disease (GERD) mediated by interleukin (IL) 8, IL1β,^2,3 and hypoxia-inducible factors.^4,5 These observations demonstrate a lymphocyte predominant inflammatory process over course of 1-2 weeks associated with basal zone hyperplasia and dilation of intercellular spaces.⁶ In cultured human esophageal epithelial cells and patients, it is further suggested that acid causes this chronic inflammatory reaction.

Usefulness of the Eosinophilic Esophagitis Histologic Scoring System in Distinguishing Active Eosinophilic Esophagitis From Remission and Gastroesophageal Reflux Disease

BackgroundEosinophilic esophagitis (EoE) is defined as esophageal dysfunction in the presence of > 15 intraepithelial eosinophils per high-power field (eos/hpf) in either the mid or distal esophagus. The current focus of EoE pathologic evaluation is the peak eosinophil count (PEC), although histologic features other than eosinophilic inflammation are also commonly observed. In addition, histologic variance between the mid and distal esophagus in EoE has not been rigorously studied. The aim of our study was to utilize a recently developed EoE histologic scoring system (EoEHSS) to compare the mid and the distal esophageal histology in patients with active EoE (EoE-A), EoE in remission (EoE-R), and gastroesophageal reflux disease (GERD).MethodsEoEHSS was used to prospectively evaluate the severity and extent of changes in multiple histopathologic features (PEC; basal zone hyperplasia (BZH); eosinophilic abscesses (EA); eosinophil surface layering (ESL); dilated intercellular spaces (DIS); surface epithelial alteration (SEA); dyskeratotic epithelial cells (DEC); lamina propria fibrosis (LPF)) in the mid and distal esophageal biopsies in 85 pediatric patients at a tertiary medical center. These patients were divided into three cohorts: EoE-A (n = 36), EoE-R (n = 12) and GERD (n = 37).ResultsTotal grade (severity) and stage (extent) scores were significantly higher in EoE-A compared to EoE-R and GERD patients in both the mid and the distal esophagus. The mean total grade scores in the mid esophagus, but not the distal esophagus remained higher in EoE-R as compared to GERD patients. Specific histopathologic features independent of PEC were different in distal and mid esophagus in EoE-A. About one-half of children with active EoE had different EoEHSS scores in their mid and distal esophageal biopsies.ConclusionsEoEHSS yields histologic insights beyond those derived from PEC and helps in more objective, reproducible and accurate diagnosis of EoE and GERD. It also provides a more comprehensive understanding into the pathophysiology of EoE.

Intra- and interobserver agreement of histopathological findings in pediatric patients with eosinophilic esophagitis

ObjectiveTo assess intra- and interobserver agreement among non-expert pathologists in identifying features of the eosinophilic esophagitis histologic scoring system (EoEHSS) in pediatric patients. Patients and methodsThe authors used 50 slides from patients (aged 1-15 years; 72% male) with EoE. EoEHSS evaluates eosinophilic inflammation and other features including epithelial basal zone hyperplasia, eosinophilic abscesses, eosinophil surface layering, dilated intercellular spaces, surface epithelial alteration, dyskeratotic epithelial cells, and lamina propria fibrosis. Grade and stage of abnormalities are scored using a 4-point scale (0 normal; 3 maximum change). Four pathologists determined EoEHSS findings on two occasions. Intra- and interobserver agreement was assessed using Kappa (κ) statistics and intra-class correlation coefficients. ResultsIntra- and interobserver agreement for the identification of eosinophil counts ≥ 15/high power field (HPF) was excellent, however varied when assessing additional features of the EoEHSS. For the more experienced pathologist, agreement for most EoEHSS items and the composite scores was substantial to excellent. For the less experienced pathologists, intraobserver agreement ranged from absent to substantial for individual features and ranged from moderate to substantial for the composite scores. ConclusionMost items of the EoEHSS had substantial to excellent reliability when assessed by a pathologist experienced in the diagnosis of EoE but presented lower repeatability among less experienced pathologists. These findings suggest that specific training of pathologists is required for the identification of EoEHSS characteristics beyond eosinophil count, as these features are considered useful in the evaluation of response to treatment and correlation with clinical manifestations and endoscopic findings.