Deeper Than the Epithelium: Role of Matrix and Fibroblasts in Pediatric and Adult Eosinophilic Esophagitis

Type 2 Inflammation in Eosinophilic Esophagitis: From Pathophysiology to Therapeutic Targets

Eosinophilic esophagitis (EoE) is a chronic immune-mediated disease of the esophagus characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation, whose incidence is rising. It significantly affects patients’ quality of life and, if left untreated, results in fibrotic complications. Although broad consensus has been achieved on first-line therapy, a subset of patients remains non-responder to standard therapy. The pathogenesis of EoE is multifactorial and results from the complex, still mostly undefined, interaction between genetics and intrinsic factors, environment, and antigenic stimuli. A deep understanding of the pathophysiology of this disease is pivotal for the development of new therapies. This review provides a comprehensive description of the pathophysiology of EoE, starting from major pathogenic mechanisms (genetics, type 2 inflammation, epithelial barrier dysfunction, gastroesophageal reflux, allergens, infections and microbiota) and subsequently focusing on the single protagonists of type 2 inflammation (involved cells, cytokines, soluble effectors, surface proteins and transcription factors) that could represent present and future therapeutic targets, while summarizing previous therapeutic approaches in literature.

Intrabolus Pressure Has Better Correlation Than Eosinophilia with Dysphagia Severity in Fibrostenotic Eosinophilic Esophagitis: A Pilot Study

Eosinophilic esophagitis is characterized by dysphagia with esophageal eosinophilia. We sought to determine if intrabolus pressure measurements on high-resolution manometry had any correlation with dysphagia improvement following standard therapy for patients with fibrostenotic eosinophilic esophagitis. Consecutive patients were prospectively enrolled at our swallowing center. Dysphagia scores, esophageal eosinophil counts, endoscopic reference scores, and intrabolus pressure measurements were compared at baseline and following therapy with 8 weeks of a proton-pump inhibitor and serial bougie dilation to a luminal diameter of 17 mm. Five patients were included in the study. The median age was 38 years. The average endoscopic reference score improved from 5.0 to 2.4 (p = 0.007). The mean esophageal diameter improved from 10.8 mm to 17.2 mm (p = 0.001). Dysphagia severity scores improved from a mean value of 34.2 to 10.8 (p = 0.004). Mucosal eosinophilia had no correlation with dysphagia severity. Mean intrabolus pressure improved from 21.8 mmHg to 11 mmHg (p = 0.001). There was strong correlation between a decrease in intrabolus pressure and improvement in dysphagia severity; however, this was not significant (p = 0.108). Intrabolus pressure has strong correlation with dysphagia severity following therapy for fibrostenotic eosinophilic esophagitis. Bougie dilation provides improvement in dysphagia despite persistent mucosal eosinophilia.

Eosinophilic Esophagitis: Pathophysiology and Definition

Eosinophilic esophagitis is an adaptive immune response to patient-specific antigens, mostly foods. Eosinophilic esophagitis is not solely IgE-mediated and is likely characterized by Th2 lymphocytes with an impaired esophageal barrier function. The key cytokines and chemokines are thymic stromal lymphopoeitin, interleukin-13, CCL26/eotaxin-3, and transforming growth factor-β, all involved in eosinophil recruitment and remodeling. Chronic food dysphagia and food impactions, the feared late complications, are related in part to dense subepithelial fibrosis, likely induced by interleukin-13 and transforming growth factor-β.

Creating a multi-center rare disease consortium - the Consortium of Eosinophilic Gastrointestinal Disease Researchers (CEGIR)

 Eosinophilic gastrointestinal disorders (EGIDs) affect various segments of the gastrointestinal tract. Since these disorders are rare, collaboration is essential to enroll subjects in clinical studies and study the broader population. The Rare Diseases Clinical Research Network (RDCRN), a program of the National Center for Advancing Translational Sciences (NCATS), funded the Consortium of Eosinophilic Gastrointestinal Disease Researchers (CEGIR) in 2014 to advance the field of EGIDs. CEGIR facilitates collaboration among various centers, subspecialties, patients, professional organizations and patient-advocacy groups and includes 14 clinical sites. It has successfully initiated two large multi-center clinical studies looking to refine EGID diagnoses and management. Several pilot studies are underway that focus on various aspects of EGIDs including novel therapeutic interventions, diagnostic and monitoring methods, and the role of the microbiome in pathogenesis. CEGIR currently nurtures five physician-scholars through a career training development program and has published more than 40 manuscripts since its inception. This review focuses on CEGIR's operating model and progress and how it facilitates a framework for exchange of ideas and stimulates research and innovation. This consortium provides a model for progress on other potential clinical areas.