2015 David Y. Graham Lecture: The First Two Decades Of Eosinophilic Esophagitis-From Acid Reflux To Food Allergy

Clinicopathological Differences between Eosinophilic Esophagitis and Asymptomatic Esophageal Eosinophilia

Objective According to consensus guidelines, eosinophilic esophagitis (EoE) is defined as a clinicopathological entity whose symptoms and histology must always be considered together. However, endoscopic findings typical of EoE are often seen in asymptomatic esophageal eosinophilia (aEE). We aimed to clarify the clinicopathological features of aEE. Methods We retrospectively compared cases of aEE and those of symptomatic EoE. Materials We reviewed 146 patients who underwent upper gastrointestinal endoscopy and were confirmed histopathologically to have esophageal eosinophil infiltration of at least 15 eosinophils per high-power field. They were divided into the aEE group (n=75) and the EoE group (n=71). Patients' clinicopathological findings were then collected and examined. Results The EoE group experienced dysphagia (47.9%), heartburn (40.8%), food impaction (40.8%), chest pain (16.9%), and other symptoms (8.5%). There was no significant difference between the two groups with regard to age, sex, current smoking status, or alcohol consumption. The aEE group had a significantly higher body mass index (p<0.01) and significantly lower frequency of concurrent allergic diseases (p<0.01) than the EoE group. No significant differences were found between the two groups with regard to the mean peripheral blood eosinophil count, non-specific immunoglobulin E concentration, peak eosinophil infiltration in the biopsy specimens, EoE histology scoring system, phenotype and location of typical endoscopic findings of EoE, or thickness of the esophagus wall or the mucosal and submucosal layer as measured by endoscopic ultrasonography. Two patients in the aEE group who were followed up without treatment subsequently developed esophageal symptoms. Conclusion aEE and EoE may have the same clinicopathological features.

Challenges and updates in the management of eosinophilic esophagitis

Eosinophilic esophagitis (EE) is a chronic T helper cell-2 mediated inflammatory condition and is considered as a primary cause of dysphagia and foregut symptoms. There are many challenges regarding the treatment options of EE. Different therapeutic approaches are best at meeting different endpoints. There are unresolved questions such as whether the goal for treatment should be to control esophageal eosinophilia and inflammation or to achieve symptomatic improvement. Still, proton pump inhibitors are used in differential diagnosis, along with their anti-inflammatory and anti-acid properties. Conducted trials continue to recommend the use of topical corticosteroids and empiric food elimination diets as first-line therapeutic modalities. The growing knowledge on the pathogenesis of EE has allowed further progression of encouraging targeted biologic therapies. However, the guidelines for EE management should be updated accordingly in the coming years, including fast evolving data on non-invasive diagnostic strategies, new treatment modalities, and the long-term prognosis of the disease.

Is Asymptomatic Esophageal Eosinophilia the Same Disease Entity as Eosinophilic Esophagitis?

Eosinophilic esophagitis (EoE) is an allergic inflammatory disorder that is characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation.^1,2 Its prevalence has been increasing rapidly in both Western and Asian countries. In Japan, most of the cases of esophageal eosinophilia (EE) are found in an upper endoscopy examination for gastric cancer screening performed during a comprehensive health check-up.^3,4 Indeed, we frequently encounter patients with asymptomatic EE showing typical endoscopic findings, such as linear furrows, as well as histologic findings compatible with EoE. However, the current clinical guidelines for EoE diagnosis include symptoms related to esophageal dysfunction, thus patients without symptoms do not fulfill the diagnostic criteria.^1,2 The clinical characteristics remain to be fully elucidated,⁵ thus we aimed to clarify clinical features of asymptomatic EE as compared with those of EoE.

Future Directions in Eosinophilic Esophagitis

Eosinophilic esophagitis advances parallel the increased prevalence. Developments include refining the diagnostic criteria, identifying risk factors, appreciating the contribution of inflammatory pathways, recognizing the importance of subepithelial remodeling, validating trial endpoints, defining a role for biological therapies, and optimizing dietary therapy. Endoscopic outcomes have emerged as endpoints in trials of novel therapeutics. Expanding efforts seek to develop less-invasive methods to assess disease activity thereby reducing the burden of repeated endoscopic procedures during elimination diets. The functional lumen imaging probe is now identified as a determinant of complications with potential utility as a therapeutic endpoint.

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.

Psychometric validation of the Dysphagia Symptom Questionnaire in patients with eosinophilic esophagitis treated with budesonide oral suspension

Background

Eosinophilic esophagitis (EoE) is characterized by high levels of eosinophils in the esophageal mucosa. Patients with the disease present with a range of symptoms, including dysphagia (difficulty swallowing). The aim of this analysis was to assess the psychometric properties of the Dysphagia Symptom Questionnaire (DSQ), a patient-reported outcome (PRO) measure of dysphagia associated with EoE. Psychometric properties of the DSQ were assessed using data collected from a 12-week, phase 2, multicenter, randomized, double-blind, placebo-controlled trial of budesonide oral suspension in adolescents and adults (11–40 years old) with EoE.

Results

The study population comprised 93 patients with EoE; 94.6% of whom were white, 68.8% were male and the mean age (standard deviation) was 21.6 (7.7) years. Patients had been diagnosed with EoE for a mean of 37.6 months before study initiation. The DSQ was feasible to implement with few item-level data missing at baseline. Item discrimination was high, with floor and ceiling effects below the predefined threshold (≤9%). Higher DSQ scores corresponded with presence and increased severity of dysphagia, indicative of strong item discrimination among patients at baseline (threshold >50%). The DSQ was able to detect changes in symptoms over time and produced similar outcomes to those from physician- and other patient-rated measures, supportive of construct validity. The DSQ had strong test–retest reliability (intraclass correlation coefficient, r = 0.82); and was also responsive to disease-level changes, with higher DSQ scores corresponding to increased esophageal eosinophilic burden. Lastly, the percentage changes in the minimal clinically important difference and clinically important difference in DSQ score were estimated at −27.4% and −55.4%, respectively.

Conclusions

These analyses support the DSQ as a valid and reliable measure of dysphagia in patients with EoE. Changes in DSQ scores suggest a level of agreement between clinician, patient and histologic response. The DSQ should therefore be considered a viable PRO measure of dysphagia for use in future therapeutic studies of EoE.

The influence of Helicobacter pylori on the ethnic distribution of esophageal eosinophilia

BACKGROUND

Environmental factors associated with ethnicity may contribute to the occurrence of eosinophilic esophagitis. Our study aimed to investigate the influence of Helicobacter pylori on the ethnic variation of esophageal eosinophilia in a large national sample of patients undergoing esophago-gastro-duodenoscopy.

METHODS

The Miraca Life Sciences Database is an electronic repository of histopathologic patient records. A case-control study evaluated the influence of ethnicity on the occurrence of esophageal eosinophilia and how age, gender, and histologic diagnosis of H. pylori modify this relationship.

RESULTS

The total study population comprised 596 479 subjects, of whom 25 969 harbored a diagnosis of esophageal eosinophilia. Young age, male sex, and H. pylori infection in declining order exerted the strongest influence on the occurrence of esophageal eosinophilia. In comparison with the population comprising of Caucasians and African-Americans, esophageal eosinophilia was less common among patients of African (OR=0.10, 95% CI=0.01-0.46), Middle Eastern (0.22, 0.15-0.31), East Asian (0.32, 0.26-0.38), Indian (0.28, 0.21-0.37), Hispanic (0.40, 0.37-0.43), or Jewish descent (0.58, 0.51-0.66), but more common among patients of Northern European descent (1.25, 1.07-1.45). With the exception of Northern Europeans, all ethnic subgroups were characterized by a higher prevalence of H. pylori than the comparison group. A low prevalence of H. pylori was significantly associated with a high prevalence of esophageal eosinophilia (R² =0.90, P<.001).

CONCLUSION

Esophageal eosinophilia prevalence markedly varies by patient ethnicity. As there is a strong inverse correlation between H. pylori and esophageal eosinophilia, H. pylori infection may be in part responsible for the observed ethnic distribution of esophageal eosinophilia.