Clinical and endoscopic characteristics do not reliably differentiate PPI-responsive esophageal eosinophilia and eosinophilic esophagitis in patients undergoing upper endoscopy: a prospective cohort study

Diagnosis and management of eosinophilic esophagitis in children: An update from the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN)

INTRODUCTION

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease of the esophagus characterized by symptoms of esophageal dysfunction and histologically by predominantly eosinophilic infiltration of the squamous epithelium. European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) published a guideline in 2014; however, the rapid evolution of knowledge about pathophysiology, diagnostic criteria, and therapeutic options have made an update necessary.

METHODS

A consensus group of pediatric gastroenterologists from the ESPGHAN Working Group on Eosinophilic Gastrointestinal Diseases (ESPGHAN EGID WG) reviewed the recent literature and proposed statements and recommendations on 28 relevant questions about EoE. A comprehensive electronic literature search was performed in MEDLINE, EMBASE, and Cochrane databases from 2014 to 2022. The Grading of Recommendations Assessment, Development and Evaluation system was used to assess the quality of evidence and formulate recommendations.

RESULTS

A total of 52 statements based on the available evidence and 44 consensus-based recommendations are available. A revision of the diagnostic protocol, options for initial drug treatment, and the new concept of simplified empiric elimination diets are now available. Biologics are becoming a part of the potential armamentarium for refractory EoE, and systemic steroids may be considered as the initial treatment for esophageal strictures before esophageal dilation. The importance and assessment of quality of life and a planned transition to adult medical care are new areas addressed in this guideline.

CONCLUSION

Research in recent years has led to a better understanding of childhood EoE. This guideline incorporates the new findings and provides a practical guide for clinicians treating children diagnosed with EoE.

The 1st EoETALY Consensus on the Diagnosis and Management of Eosinophilic Esophagitis-Current Treatment and Monitoring

The present document constitutes Part 2 of the EoETALY Consensus Statements guideline on the diagnosis and management of eosinophilic esophagitis (EoE) developed by experts in the field of EoE across Italy (i.e., EoETALY Consensus Group). Part 1 was published as a different document, and included three chapters discussing 1) definition, epidemiology, and pathogenesis; 2) clinical presentation and natural history and 3) diagnosis of EoE. The present work provides guidelines on the management of EoE in two final chapters: 4) treatment and 5) monitoring and follow-up, and also includes considerations on knowledge gaps and a proposed research agenda for the coming years. The guideline was developed through a Delphi process, with grading of the strength and quality of the evidence of the recommendations performed according to accepted GRADE criteria.This document has received the endorsement of three Italian national societies including the Italian Society of Gastroenterology (SIGE), the Italian Society of Neurogastroenterology and Motility (SINGEM), and the Italian Society of Allergology, Asthma, and Clinical Immunology (SIAAIC). The guidelines also involved the contribution of members of ESEO Italia, the Italian Association of Families Against EoE.

The 1st EoETALY Consensus on the Diagnosis and Management of Eosinophilic Esophagitis - Definition, Clinical Presentation and Diagnosis

Eosinophilic esophagitis (EoE) is a chronic type 2-mediated inflammatory disease of the esophagus that represents the most common eosinophilic gastrointestinal disease. Experts in the field of EoE across Italy (i.e., EoETALY Consensus Group) including gastroenterologists, endoscopists, allergologists/immunologists, and paediatricians conducted a Delphi process to develop updated consensus statements for the management of patients with EoE and update the previous position paper of the Italian Society of Gastroenterology (SIGE) in light of recent evidence. Grading of the strength and quality of the evidence of the recommendations was performed using accepted GRADE criteria. The guideline is divided in two documents: Part 1 includes three chapters, namely 1) definition, epidemiology, and pathogenesis; 2) clinical presentation and natural history, and 3) diagnosis, while Part 2 includes two chapters: 4) treatment and 5) monitoring and follow-up. This document has received the endorsement of three Italian national societies including the SIGE, the Italian Society of Neurogastroenterology and Motility (SINGEM), and the Italian Society of Allergology, Asthma, and Clinical Immunology (SIAAIC). With regards to patients' involvement, these guidelines involved the contribution of members of ESEO Italia, the Italian Association of Families Against EoE.

Twice-Daily Proton Pump Inhibitor Induces Higher Remission Rate in Eosinophilic Esophagitis Than Once-Daily Regimen Regardless of Total Daily Dose

INTRODUCTION

The optimal proton pump inhibitor (PPI) regimen for eosinophilic esophagitis (EoE) is unclear. We compared histologic response rates of different dosing combinations.

METHODS

A total of 305 patients with newly diagnosed EoE received standard (omeprazole 20 mg daily), once-daily moderate (40 mg daily), twice-daily moderate (20 mg twice daily), or high (40 mg twice daily) dose PPI for ≥8 weeks.

RESULTS

Approximately 42.3% achieved histologic response to PPI, with higher rates for twice-daily (moderate 52.8%/high 54.3%) than once-daily (standard 11.8%/moderate 10%) dosing ( P < 0.0001). On multivariable analysis, twice-daily moderate (adjusted odds ratio 6.75, confidence interval 2.53-18.0, P = 0.0008) and high (adjusted odds ratio 12.8, confidence interval 4.69-34.8, P < 0.0001) doses independently predicted histologic response.

DISCUSSION

Twice-daily PPI is associated with higher EoE histologic response rates than once-daily regimen.

High prevalence of response to PPI treatment in children and adolescents with eosinophilic esophagitis in southern Brazil

Introduction

Eosinophilic esophagitis is a newly recognized entity, in which there is significant evidence available that clearly demonstrates the positive impact of PPIs on reducing esophageal eosinophilia in individuals across different age groups, including children, adolescents, and adults. Multiple mechanisms have been proposed to explain how this treatment effect occurs. In Brazil, there seems to be a lack of studies that have prospectively assessed the clinical and therapeutic response rate in pediatric patients with EoE. The objective of this study was to prospectively evaluate the clinical and therapeutic response of pediatric patients with EoE in a medical center located in southern Brazil, by investigating the effectiveness of PPI treatment.

Methods

This study is a clinical, prospective, open trial that took place in a pediatric hospital located in southern Brazil. The focus of the study was on patients diagnosed with Eosinophilic Esophagitis (EoE) who were given treatment using omeprazole/esomeprazole at a dosage of 1 mg.kg per dose, twice daily, for a period of 8-12 weeks. Following the treatment period, the patients underwent another endoscopy. Patients who exhibited 15 or less eosinophils in the biopsy conducted after the treatment were considered as responders.

Results

A total of 27 patients was evaluated (74.1% boys). The average age (± standard deviation) was 8 years (±4). Nineteen patients (70.3%) were considered as responders to PPI treatment: 6 patients-22.2%-exhibited a complete response (defined as having 5 or fewer eosinophil per high power field. Additionally, 13 patients-48.1%-demonstrated a partial response, characterized by eosinophil counts exceeding 5 but less than 15 eos/hpf. When comparing the responder and non-responder groups at presentation, a statistical difference was observed in the prevalence of food refusal as a presenting symptom. Food refusal was found to be more prevalent in the non-responder group (87.5% vs. 26.3%, P = 0.008). No differences were observed in terms of atopy history and endoscopic scores. Upon comparing the histological findings from the post-treatment endoscopy of the two groups, it was observed that PPI responders exhibited a greater tendency to decrease basal cell hyperplasia (P = 0.06) and intercellular edema (P = 0.08).

Conclusion

In this group of pediatric patients with EoE in Southern Brazil most patients showed a high prevalence of histological, endoscopic, and clinical response to PPI treatment. PPIs showed efficacy in Brazilian patients with EoE, most of whom would probably not be able to adequately undergo other treatments.

Clinical Trial Registration

https://ensaiosclinicos.gov.br/rg/RBR-2ntbth9, identifier (U1111-1301-1842).

Proton-Pump Inhibitors in Eosinophilic Esophagitis: A Review Focused on the Role of Pharmacogenetics

Proton-pump inhibitors (PPIs) are the most administered first-line treatment for eosinophilic esophagitis (EoE). However, only around half of EoE patients respond histologically to a double dosage of PPI. In addition, 70% of responders maintain EoE in remission after tapering the PPI dose. In order to avoid endoscopy with biopsies-the only accurate method of assessing PPI response-efforts have been made to identify PPI responder patients. The clinical or endoscopic features and biomarkers evaluated so far, however, have not proven to be sufficient in predicting PPI response. Although new approaches based on omics technologies have uncovered promising biomarkers, the specialized and complex procedures required are difficult to implement in clinical settings. Alternatively, PPI pharmacogenetics based on identifying variations in CYP2C19 and STAT6 genes have shown promising results in EoE, and could easily be performed in most laboratories. Other genetic variations have also been associated with PPI response and may explain those cases not related to CYP2C19 or STAT6. Here, we provide an overview of PPI treatment in EoE and evidence of how genetic variations in CYP2C19 and other genes could affect PPI effectiveness, and also discuss studies evaluating the role of pharmacogenetics in predicting PPI response in patients with EoE.

Allergic phenotype identified on allergen testing is associated with proton pump inhibitor nonresponse in eosinophilic esophagitis

BACKGROUND AND AIM

Food/environmental allergens have been associated with eosinophilic esophagitis (EoE); however, the correlation between allergy profiles and disease responsiveness to proton pump inhibitor (PPI) therapy remains unclear. We aimed to assess the association between food/environmental allergies identified on allergen testing and histologic response to PPI in patients with treatment-naive EoE.

METHODS

Adults with newly diagnosed EoE who underwent formal testing for food/environmental allergies at a tertiary center were included. All patients underwent twice-daily PPI for 8 weeks with subsequent repeat endoscopy and biopsy to assess histologic response. Patients with <15 eosinophils/hpf on post-PPI mucosal biopsies were classified as responders (PPI-r-EoE), while those with ≥15 eosinophils/hpf were nonresponders (PPI-nr-EoE).

RESULTS

Sixty-one patients met inclusion criteria (21 PPI-r-EoE vs 40 PPI-nr-EoE). Demographic, clinical, and endoscopic finding variables were similar between groups. Positive food allergen test was more prevalent among PPI-nr-EoE patients (82.5% vs 42.9%, P = 0.003). On multivariable analysis, positive food allergen testing remained an independent predictor for PPI nonresponse (aOR 0.15, CI: 0.04-0.58, P = 0.0006). Positive environmental allergen testing was highly prevalent, with no significant differences between groups (77.5% vs 95.2%, P = 0.14). However, higher number of positive environmental allergens (23.3% [≥5 allergens] vs 73.3% [<5 allergens], P = 0.003) and specific aeroallergens correlated with PPI-nr-EoE.

CONCLUSION

Positive food allergy testing and increased environmental allergens predicted lower likelihood of histologic response to PPI in EoE. Our findings support an allergic phenotype of EoE that may less likely respond to PPI therapy. Formal allergen testing may play a role in therapy selection and tailored management in EoE.

Clinical Features and Treatment Response to Topical Steroids in Ethnic and Racial Minority Patients With Eosinophilic Esophagitis

INTRODUCTION

Differences in eosinophilic esophagitis (EoE) presentation and outcomes by ethnicity or race remain understudied. We aimed to determine whether EoE patients of Hispanic/Latinx ethnicity or non-White race have differences in presentation at diagnosis or response to topical corticosteroid (tCS) treatment.

METHODS

This retrospective cohort study included subjects of any age with a new diagnosis of EoE and documentation of ethnicity or race. For those who had treatment with tCS and follow-up endoscopy/biopsy, we assessed histologic response (<15 eosinophils/hpf), global symptom response, and endoscopic response. Hispanic EoE patients were compared with non-Hispanics at baseline and before and after treatment. The same analyses were repeated for White vs non-Whites.

RESULTS

Of 1,026 EoE patients with ethnicity data, just 23 (2%) were Hispanic. Most clinical features at presentation were similar to non-Hispanic EoE patients but histologic response to tCS was numerically lower (38% vs 57%). Non-White EoE patients (13%) were younger at diagnosis and had less insurance, lower zip code-level income, shorter symptom duration, more vomiting, less dysphagia and food impaction, fewer typical endoscopic features, and less dilation. Of 475 patients with race data treated with tCS, non-Whites had a significantly lower histologic response rate (41% vs 59%; P = 0.01), and odds of histologic response remained lower after controlling for potential confounders (adjusted odds ratio 0.40, 95% confidence intervals: 0.19-0.87).

DISCUSSION

Few EoE patients at our center were Hispanic, and they had similar clinical presentations as non-Hispanics. The non-White EoE group was larger, and presentation was less dysphagia-specific. Non-White patients were also less than half as likely to respond to tCS.

Recent Advances in the Treatment of Eosinophilic Esophagitis

Eosinophilic esophagitis is an increasingly common inflammatory allergic disease of the esophagus characterized by esophageal eosinophilia and symptoms of esophageal dysfunction. The therapeutic landscape has rapidly evolved for this emerging type 2 inflammatory disorder. We review traditional therapies including updates and expert opinions in addition to promising therapies on the horizon and the history of therapies that failed to meet end points and highlight knowledge gaps for future investigations.

Effect of Proton Pump Inhibitor Treatment in "PPI Non-responsive" Patients with Eosinophilic Esophagitis

BACKGROUND AND AIMS

Some eosinophilic esophagitis (EoE) patients can have a decline in eosinophil count after proton pump inhibitor (PPI) treatment without achieving histologic response, but little is known about this group. We aimed to determine the effect of PPIs on reducing esophageal eosinophilia in patients deemed non-responsive to PPI therapy.

METHODS

We analyzed prospectively collected cohort data from newly diagnosed adults with EoE who were histologic non-responders (≥15 eos/hpf) to PPI-only therapy. Symptoms, endoscopic histologic features were assessed before and after PPI. Pre- and post-PPI treatment esophageal biopsies were read by pathologists to determine peak eosinophil counts and other histologic findings.

RESULTS

Of 125 patients, peak eosinophil counts were 102.1 ± 69.8 and 102.9 ± 101.1 (p=0.93) before and after PPI treatment, respectively, but lamina propria fibrosis decreased from 97% to 41% (p<0.001). Heartburn frequency also decreased (19% to 11%; p=0.006), though endoscopic findings did not change. There were 75 patients (60%) who had some decrease in eosinophil counts, with 30 patients (24%) having ≥50% decrease in counts. When comparing the ≥50% and <50% decrease groups, differences in endoscopic features were identified, but the ≥50% group had improvement in eosinophil degranulation, microabscesses, spongiosis, and basal cell hyperplasia.

CONCLUSION

Peak eosinophil counts did not decrease overall after PPI treatment, but symptoms of heartburn improved. Approximately a quarter had ≥50% decrease in eosinophil counts, with associated decreases in other histologic findings. Further research may consider what role PPIs have in this subset of non-responders or in combination therapies.

Assessment of the clinical and allergy profiles of PPI responsive and non-responsive eosinophilic esophagitis

A subset of patients with eosinophilic esophagitis (EoE) respond to proton-pump inhibitor (PPI) therapy, however they cannot be distinguished prior to PPI trial and the mechanism of PPI response remains unclear. Improved understanding of the distinct patient phenotypes in PPI-responsive EoE (PPI-r-EoE), PPI-non-responsive EoE (PPI-nr-EoE) and erosive esophagitis (EE) may help guide management. The aim of this paper is to compare the clinical and allergy profiles of PPI-r-EoE versus PPI-nr-EoE and EE. This was a retrospective case-control study of EoE patients (>15 eos/hpf on esophageal biopsies) at a tertiary center. EE controls were identified from the pathology database. EoE patients were classified as PPI-r-EoE or PPI-nr-EoE based on histologic response to twice-daily PPI for ≥8 weeks. Patient demographics, comorbidities, symptoms, allergy history and endoscopic findings were recorded. Univariate analyses were performed using the Fisher-exact test or t-test. Multivariable analyses were performed using logistic regression. In all, 104 EoE (57 PPI-r-EoE/47 PPI-nr-EoE) and 80 EE subjects were included. On multivariable analyses, allergic conditions (aOR 20.1, P < 0.0001) and rings (aOR 108.3, P = 0.001) were independent predictors for PPI-r-EoE versus EE, whereas allergic conditions (aOR 4.8, P = 0.03), rings (aOR 27.5, P = 0.002) and furrows (aOR 17.1, P = 0.04) were independent predictors for PPI-nr-EoE versus EE. Esophageal rings was the only significant predictor found in PPI-nr-EoE versus PPI-r-EoE (OR 2.5, P = 0.03). Allergic conditions and esophageal rings are significantly more prevalent in PPI-r-EoE and PPI-nr-EoE compared with EE. PPI-r-EoE appears clinically similar to PPI-nr-EoE and significantly different from EE. Further studies are needed to delineate the underlying pathophysiology of PPI-r-EoE versus PPI-nr-EoE.

Long-term efficacy of proton pump inhibitors as a treatment modality for eosinophilic esophagitis

BACKGROUND

Proton pump inhibitors (PPIs) are a first-line treatment for EoE, but data are limited concerning response durability. We aimed to determine long-term outcomes in EoE patients responsive to PPI-therapy.

METHODS

We conducted a retrospective cohort study of newly diagnosed adults with EoE who had initial histologic response (<15 eosinophils per high-power-field) to PPI-only therapy. We extracted data regarding their subsequent clinical course and outcomes. We compared findings between the initial PPI-response endoscopy and the final endoscopy, and assessed factors associated with loss of PPI response.

RESULTS

Of 138 EoE patients with initial histologic response to PPI, 50 had long-term endoscopic follow-up, 40 had clinical follow-up, 10 changed treatments, and 38 had no long-term follow-up. Of those with endoscopic follow-up, mean follow-up-time was 3.6 ± 2.9 years; 30 and 32 patients (60%; 64%) maintained histologic and symptom responses, respectively. However, fibrotic endoscopic findings of EoE were unchanged. Younger age (aOR 1.05, 95% CI: 1.01-1.11) and dilation prior to PPI treatment (aOR 0.21, 95% CI: 0.05-0.83) were the only factors associated with long-term loss of PPI response.

CONCLUSIONS

Long-term histologic and clinical response rates for PPI therapy were 60% and 64%, respectively. Younger age and dilation at baseline were associated with histologic loss of response. These data can inform long-term EoE treatment selection.

Characterization of Eosinophilic Esophagitis From the European Pediatric Eosinophilic Esophagitis Registry (pEEr) of ESPGHAN

OBJECTIVES

Few pediatric data on phenotypic aspects of eosinophilic esophagitis (EoE) are available. The pEEr registry was developed to prospectively characterize children with EoE from Europe and Israel.

METHODS

pEEr is an ongoing prospective registry enrolling children with esophageal eosinophilia (≥15 eos/HPF). Anonymized data were collected from 19 pediatric centers. Data regarding demographics, clinical manifestations, endoscopy, histology, and therapies were collected.

RESULTS

A total of 582 subjects (61% male) were analyzed. The median age at diagnosis was 10.5 years [interquartile range (IQR): 5.7-17.7], whereas the age at symptom onset was 9.2 years (IQR: 4.3-16.4), resulting in a median diagnostic delay of 1.2 years (IQR: 0.7-2.3). The diagnostic delay was longer below age <6 years. Shorter diagnostic delays were associated with the presence of food allergy or a family history for EoE. Symptoms varied by age with dysphagia and food impaction more common in adolescents, while vomiting and failure to thrive more common in younger children ( P < 0.001). Among endoscopic findings, esophageal rings were more common in adolescents, whereas exudates were more frequent in younger children( P < 0.001). Patients who responded to proton pump inhibitors (PPIs) were more likely to be older, males, and less often presented severe endoscopic findings. Patients unresponsive to PPIs received topical steroids (40%), elimination diet (41%), or a combined therapy (19%).

CONCLUSIONS

EoE findings vary according to age in pediatric EoE. Young children are commonly characterized by non-specific symptoms, atopic dermatitis, food allergy, and inflammatory endoscopic lesions. Adolescents usually have dysphagia or food impaction, fibrostenotic lesions, and a better PPI response.

British Society of Gastroenterology (BSG) and British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN) joint consensus guidelines on the diagnosis and management of eosinophilic oesophagitis in children and adults

BACKGROUND

Eosinophilic oesophagitis (EoE) is an increasingly common cause of dysphagia in both children and adults, as well as one of the most prevalent oesophageal diseases with a significant impact on physical health and quality of life. We have provided a single comprehensive guideline for both paediatric and adult gastroenterologists on current best practice for the evaluation and management of EoE.

METHODS

The Oesophageal Section of the British Society of Gastroenterology was commissioned by the Clinical Standards Service Committee to develop these guidelines. The Guideline Development Group included adult and paediatric gastroenterologists, surgeons, dietitians, allergists, pathologists and patient representatives. The Population, Intervention, Comparator and Outcomes process was used to generate questions for a systematic review of the evidence. Published evidence was reviewed and updated to June 2021. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system was used to assess the evidence and make recommendations. Two rounds of voting were held to assess the level of agreement and the strength of recommendations, with 80% consensus required for acceptance.

RESULTS

Fifty-seven statements on EoE presentation, diagnosis, investigation, management and complications were produced with further statements created on areas for future research.

CONCLUSIONS

These comprehensive adult and paediatric guidelines of the British Society of Gastroenterology and British Society of Paediatric Gastroenterology, Hepatology and Nutrition are based on evidence and expert consensus from a multidisciplinary group of healthcare professionals, including patient advocates and patient support groups, to help clinicians with the management patients with EoE and its complications.

Non-oesophageal eosinophilic gastrointestinal diseases are undersuspected clinically and underdiagnosed pathologically

BACKGROUND

Non-oesophageal gastrointestinal eosinophilic diseases (EGID) are considered rare. However, low disease awareness among clinicians and pathologists may contribute to underdiagnosis.

AIMS

To determine how frequently requests to evaluate for EGID accompany gastrointestinal biopsies and in what proportion of suspected cases pathologists address these requests, either confirming or refuting the clinical suspicion.

METHODS

All cases in which biopsy requisitions included an explicit suspicion of EGID were extracted from a large clinicopathologic database and manually reviewed for accuracy. The diagnoses for these cases were then analysed to determine whether clinical suspicions were confirmed, refuted or ignored.

RESULTS

Eosinophilic oesophagitis (EoE) was suspected in 12.8% of 903,516 patients with biopsies and confirmed in 14.9% of them. A suspicion of eosinophilic gastritis accompanied <0.001% of 1,438,206 gastric biopsy sets and was confirmed in 11.5% of them; eosinophilic duodenitis was suspected in 0.02% of ~675,519 patients with duodenal biopsies and confirmed in 8.0% of these; eosinophilic colitis was mentioned in <0.001% of 2,504,485 patients with colonic biopsies and confirmed in 0.1% of them. Less than 3% of endoscopists mentioned non-oesophageal EGID in the requisition, while most expressed a clinical suspicion of Barrett oesophagus, Helicobacter pylori gastritis, celiac disease and microscopic colitis (in 21.2%, 49.2%, 1% and 6.4% of the cases, respectively).

CONCLUSIONS

Gastroenterologists and pathologists commonly address and diagnose EoE. In contrast, both clinical suspicion and diagnosis of non-oesophageal EGID are extremely rare. Increased clinical awareness might result in a better understanding of the epidemiology and improved diagnosis of these still elusive conditions.

[Diagnosis and Treatment of Eosinophilic Esophagitis]

Eosinophilic esophagitis (EoE) is a chronic, immune/antigen-mediated esophageal disease characterized by symptoms of esophageal dysfunction and eosinophil-predominant inflammation. The diagnostic criteria for EoE have changed with our growing knowledge over the past two decades. Esophageal eosinophilia, which responds histologically to a proton pump inhibitor (PPI) is not a distinct disease but a subset of EoE. An endoscopic scoring system that relies on the assessment of exudates, rings, edema, furrows, and strictures is a useful tool for assessing endoscopic severity. PPIs are regarded as safe and effective first-line treatments for EoE. Oral topical corticosteroids or dietary therapy are also options for first-line treatment. Endoscopic dilation is effective for relieving the dysphagia symptoms of a patient with an esophageal stricture.

Pharmacotherapies in eosinophilic esophagitis: state of the art

Eosinophilic esophagitis is a chronic immune-mediated esophageal disease with a Th2 inflammatory response to inhalant and food allergens that cause an eosinophilic infiltration of esophageal mucosa. The diagnosis requires an upper endoscopy with esophageal bioptic samples, in particular the number of eosinophils must be >15 eos/high power field. The main symptoms of EoE in adults are dysphagia and food impaction, and its incidence is growing. Nowadays, the etiology of EoE is not well understood and no standard therapy is available. Therefore, the aim of this review was to analyze the major studies present in literature regarding the various therapeutic approaches to this disease.

A Narrative Review on Efficacy and Safety of Proton Pump Inhibitors in Children

Proton pump inhibitors (PPIs) are among the most prescribed drugs worldwide and include omeprazole, esomeprazole, lansoprazole, pantoprazole, and rabeprazole. Their use in pediatrics is approved for children older than 1 year, for the short-term treatment of symptomatic gastroesophageal reflux disease (GERD), healing of erosive esophagitis, treatment of peptic ulcer disease, and eradication of Helicobacter pylori. PPIs are also considered the standard of care for pediatric eosinophilic esophagitis. Despite the strict range of indications, the use of this class of molecules has increased in all pediatric age ranges. The long-term gastric acid suppression in children has been linked to increased risks of gastrointestinal and lower respiratory tract infections, bone fractures, and allergy. This study aims to provide a comprehensive overview of the mechanism of actions, use (and misuse) in infants and children, and safety of PPIs.

Proton Pump Inhibitor Therapy for Eosinophilic Esophagitis: History, Mechanisms, Efficacy, and Future Directions

Over the past decade, the role of proton pump inhibitor (PPI) medication has evolved from a diagnostic tool for Eosinophilic Esophagitis (EoE), by excluding patients with PPI responsive esophageal eosinophilia (PPI-REE), to a therapy for EoE. This transition resulted from the Updated International Consensus Diagnostic Criteria for Eosinophilic Esophagitis: Proceedings of the Appraisal of Guidelines for Research and Evaluation II (AGREE) Conference to support PPI therapy for EoE in children and adults. Additional recent advances have suggested a role for genetic variations that might impact response to PPI therapy for EoE. This review article will explore a brief background of EoE, the evolution of PPI therapy for EoE and its proposed mechanisms, efficacy and safety in children and adults, and considerations for future PPI precision medicine in patients with EoE.

Responsiveness of a Histologic Scoring System Compared With Peak Eosinophil Count in Eosinophilic Esophagitis

INTRODUCTION

The optimal instrument for assessing histologic disease activity in patients with eosinophilic esophagitis (EoE) is unclear. We assessed the responsiveness of the EoE Histologic Scoring System (EoE-HSS) when compared with that of the peak eosinophil count (PEC).

METHODS

Histopathology slides were obtained from patients with EoE at baseline and after 8 weeks of treatment with swallowed topical budesonide or elimination diet. Two blinded gastrointestinal pathologists scored biopsies on the EoE-HSS, PEC, and 100-mm visual analog scale (VAS) of overall histologic severity. Change was defined as an improvement by ≥0.5 SD in baseline VAS. Responsiveness was quantified using the standardized effect size (SES) and the probability that the index distinguishes a patient with improvement from a patient without improvement, which is the area under the receiver operating characteristic curve (AUC). Longitudinal validity was assessed using Pearson correlations between changes in EoE-HSS and both PEC and VAS.

RESULTS

The EoE-HSS grade (SES 2.18 [95% confidence interval, CI: 1.46-2.88]; AUC 0.73 [95% CI: 0.57-0.84]) and stage (SES 2.07 [95% CI: 1.37-2.77]; AUC 0.73 [95% CI: 0.58-0.84]) were highly responsive, similar to PEC (SES 1.44 [95% CI: 0.80-2.07]; AUC 0.73 [95% CI: 0.58-0.84]). The EoE-HSS grade and stage were more highly correlated with changes in VAS (grade 0.92 [95% CI: 0.86-0.95]; stage 0.89 [95% CI: 0.81-0.94]) than with changes in PEC (grade 0.74 [95% CI: 0.58-0.85]; stage 0.66 [95% CI: 0.47-0.80]).

DISCUSSION

The EoE-HSS is highly responsive, performs similarly to PEC, and is better correlated with changes in overall histologic activity in patients with EoE.

Eosinophil-Derived Neurotoxin Predicts Response to Proton-Pump Inhibitor Treatment in Pediatric Eosinophilic Esophagitis

OBJECTIVES

There are no tests or patient factors to help predict the best treatment approach for a patient with eosinophilic esophagitis (EoE). The prevalence of proton-pump inhibitor (PPI) responsive EoE in children ranges from 30% to 71% with multiple studies showing similar characteristics in responders and nonresponders. Eosinophil-derived neurotoxin (EDN), an eosinophilic granule protein, measured in esophageal brushing has been shown to be a viable measure of disease activity in EoE. Our aim is to determine if EDN can help predict response to PPI in pediatric patients with EoE.

METHODS

We conducted a prospective cross-sectional study to compare EDN between PPI-responsive and PPI-nonresponsive EoE subjects from 2018 through 2020. Enrolled patients with active EoE were treated with high-dose PPI and underwent repeat endoscopy to determine PPI-responsiveness. EDN was measured at baseline endoscopy, before any treatment, and at follow up endoscopy, after PPI therapy. Subjects were divided into PPI-responsive and nonresponsive groups. EDN, endoscopic reference score (EREFS), and peak eosinophilic count (PEC) were compared.

RESULTS

Fifteen out of the 36 enrolled subjects with EoE (age range 2-18 years, 73.3% male) were PPI-responsive and 21 (age range 2-19 years, 95.2% male) were PPI-nonresponsive. EDN concentration was significantly higher in the PPI-nonresponsive group than in the PPI-responsive group (219.1 ± 229 mcg/mL vs 75.7 ± 60 mcg/mL, respectively, P = 0.036). There was no difference between the two groups in EREFS (P = 0.55) or PEC (P = 0.15).

CONCLUSIONS

EDN measured in esophageal epithelial samples obtained by brushing during endoscopy may predict PPI-responsiveness in children and young adults with EoE.

Barrier Impairment and Type 2 Inflammation in Allergic Diseases: The Pediatric Perspective

Allergic diseases represent a global burden. Although the patho-physiological mechanisms are still poorly understood, epithelial barrier dysfunction and Th2 inflammatory response play a pivotal role. Barrier dysfunction, characterized by a loss of differentiation, reduced junctional integrity, and altered innate defence, underpins the pathogenesis of allergic diseases. Epithelial barrier impairment may be a potential therapeutic target for new treatment strategies Up now, monoclonal antibodies and new molecules targeting specific pathways of the immune response have been developed, and others are under investigation, both for adult and paediatric populations, which are affected by atopic dermatitis (AD), asthma, allergic rhinitis (AR), chronic rhinosinusitis with nasal polyps (CRSwNP), or eosinophilic esophagitis (EoE). In children affected by severe asthma biologics targeting IgE, IL-5 and against IL-4 and IL-13 receptors are already available, and they have also been applied in CRSwNP. In severe AD Dupilumab, a biologic which inhibits both IL-4 and IL-13, the most important cytokines involved in inflammation response, has been approved for treatment of patients over 12 years. While a biological approach has already shown great efficacy on the treatment of severe atopic conditions, early intervention to restore epithelial barrier integrity, and function may prevent the inflammatory response and the development of the atopic march.

Eosinophilic Esophagitis: Incidence, Diagnosis, Management, and Future Directions

Eosinophilic esophagitis (EoE) is an antigen-mediated esophageal disease defined by the presence of esophageal eosinophilia and symptoms of esophageal dysfunction. The pathophysiology involves an allergen-driven Th2 T cell response that triggers infiltration of eosinophils into the esophagus leading to inflammation, remodeling, and fibrosis. This results in disruption of esophageal function and accompanying symptoms - most notably dysphagia. Effective therapies target inflammation or fibrostenotic complications and include proton pump inhibitors, swallowed topical steroids, dietary exclusion, and dilation. Clinical trials testing promising biologic therapies are ongoing.

Eosinophilic Esophagitis: A Review

Importance

Eosinophilic esophagitis (EoE) is a chronic immune-mediated inflammatory disease of the esophagus that affects an estimated 34.4/100 000 people in Europe and North America. EoE affects both children and adults, and causes dysphagia, food impaction of the esophagus, and esophageal strictures.

Observations

EoE is defined by symptoms of esophageal dysfunction, such as vomiting, dysphagia, or feeding difficulties, in a patient with an esophageal biopsy demonstrating at least 15 eosinophils per high-power field in the absence of other conditions associated with esophageal eosinophilia such as gastroesophageal reflux disease or achalasia. Genetic factors and environmental factors, such as exposure to antibiotics early in life, are associated with EoE. Current therapies include proton pump inhibitors; topical steroid preparations, such as fluticasone and budesonide; dietary therapy with amino acid formula or empirical food elimination; and endoscopic dilation. In a systematic review of observational studies that included 1051 patients with EoE, proton pump inhibitor therapy was associated with a histologic response, defined as less than 15 eosinophils per high-power field on endoscopic biopsy, in 41.7% of patients, while placebo was associated with a 13.3% response rate. In a systematic review of 8 randomized trials of 437 patients with EoE, topical corticosteroid treatment was associated with histologic remission in 64.9% of patients compared with 13.3% for placebo. Patients with esophageal narrowing may require dilation. Objective assessment of therapeutic response typically requires endoscopy with biopsy.

Conclusions and Relevance

EoE has a prevalence of approximately 34.4/100 000 worldwide. Treatments consist of proton pump inhibitors, topical steroids, elemental diet, and empirical food elimination, with esophageal dilation reserved for patients with symptomatic esophageal narrowing.

Proton Pump Inhibitor Therapy in Eosinophilic Esophagitis: Predictors of Nonresponse

BACKGROUND

Identification of clinical predictors of response to first-line therapies for EoE is needed to guide initial medical management.

STUDY DESIGN

A retrospective analysis of patients diagnosed with EoE from 2011 to 2018 was conducted. Clinical and diagnostic variables including demographics, endoscopic, and esophagram findings were compared between PPI responders and PPI nonresponders. All patients underwent a standard 8-week twice-daily PPI trial, with PPI responsiveness defined as < 15 eos/hpf on repeat EGD. Univariate and multivariable analyses were conducted to identify risk factors for nonresponse, and ROC curves were created to identify cutoff values.

RESULTS

A total of 223 EoE patients (135 male, median age 39 (29-51)) were identified, with PPI nonresponse (PPI-NR) in 71% of patients. PPI-NR was seen in all 10 patients with failure of scope passage, with an OR of 9.06 by univariate analysis (P = 0.1485). In a multivariable model, age per 10 years (OR 0.71; P = 0.007), BMI per 1 kg/m² (OR 0.94; P = 0.03), and peripheral eosinophil count per 100 per mm³ (OR 1.37; P = 0.003) were independent risk factors. Dichotomization to maximize sensitivity and specificity identified age ≤ 36 years old, BMI ≤ 25.2 kg/m², and peripheral eos > 460 per mm³ as predictive thresholds for PPI-NR. The probability of PPI-NR was 72.4-84.5% with 1 risk factor, 87.9-93.8% with 2 risk factors, and 97.2% with all 3 risk factors.

CONCLUSIONS

Young age, reduced BMI, elevated peripheral eosinophil count, and likely inability to pass an endoscope predict lack of response to PPIs in patients with EoE.

A Model Using Clinical and Endoscopic Characteristics Identifies Patients at Risk for Eosinophilic Esophagitis According to Updated Diagnostic Guidelines

BACKGROUND AND AIMS

Updated diagnostic guidelines for eosinophilic esophagitis (EoE) have eliminated the requirement for a proton pump inhibitor (PPI) trial, but there are no models to identify patients with EoE based on these new criteria. We aimed to develop a predictive model for diagnosis of EoE based on the updated EoE diagnostic guidelines.

METHODS

We performed a secondary analysis of a prospective study of adult patients referred for outpatient esophagogastroduodenoscopy at University of North Carolina who had symptoms of esophageal dysfunction; patients with prevalent EoE were excluded. We analyzed data from 206 EoE cases (mean age 40.1, 62.6% male, 93.2% white) and 306 controls (mean age 52.3, 37.9% male, 79.7% white). We built predictive models for case-control status, using clinical, endoscopic, and histologic features, and defining EoE by either the new or historical definition of PPI non-response. Model discrimination was assessed by the area under the receiver-operator characteristic curve (AUC).

RESULTS

Before endoscopy, younger age, male sex, history of atopic condition or food allergy, and dysphagia identified patients with EoE with an AUC of 0.83. When we included endoscopy findings suggestive of EoE, the model identified patients with EoE with an AUC of 0.92; this increased to 0.99 when histology was included.

CONCLUSION

We developed a model to identify patients with EoE, without a trial of PPIs, based on updated diagnostic guidelines. Clinical features and endoscopic findings identified patients with EoE with an AUC of 0.92-even without histologic data and in the absence of dysphagia. This model can be used to select patients with upper gastrointestinal symptoms but without dysphagia for early diagnostic endoscopy. The model can also be used to identify cases of EoE when eosinophil counts are greater than 15 in biopsies but other causes of esophageal eosinophilia cannot necessarily be excluded.

Subjective Symptoms in Patients with Eosinophilic Esophagitis Are Related to Esophageal Wall Thickness and Esophageal Body Pressure

BACKGROUND

Endoscopic ultrasonography (EUS) and high-resolution manometry (HRM) can be used in the evaluation of eosinophilic esophagitis (EoE) for frequent symptoms such as dysphagia. However, the role of these examinations is not clear.

AIMS

The aim of this study was to objectively evaluate the subjective symptoms of EoE patients with EUS and HRM.

METHODS

Patients who had endoscopic findings indicative of EoE and matched the number of eosinophil infiltrates used as diagnostic criteria were recruited between September 2018 and August 2019. Evaluable subjects underwent EUS and HRM and completed the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire. The esophageal wall thickness (evaluated with EUS) and HRM parameters between patients with and without symptoms were retrospectively compared. Symptomatic patients were re-examined using EUS and HRM 6 months after treatment.

RESULTS

A total of 35 patients (29 males, median age of 49 years) were divided into symptomatic (20 patients) and asymptomatic groups (15 patients). The esophageal wall was thicker, and the distal contractile integral (DCI) values were higher in the symptomatic group (P < 0.001). In addition, DCI values were positively correlated with esophageal wall thickness. After treatment, the GSRS scores showed an improving trend for each item. Esophageal wall thickness and DCI values were significantly decreased (Ps < 0.001).

CONCLUSIONS

Esophageal wall thickening and increased esophageal body pressure may be involved in subjective symptoms. In addition, treatment may reduce esophageal thickness and pressure along with improvement of subjective symptoms.

Similarity and difference in the characteristics of eosinophilic esophagitis between Western countries and Japan

Over the past two decades, the incidence and prevalence of eosinophilic esophagitis (EoE) have risen rapidly, especially in Western countries, with cases in Japan also showing a gradual increase in recent years. However, similarities and differences regarding the characteristics of EoE between Western countries and Japan remain to be clearly elucidated. The current clinical guidelines for diagnosis include symptoms related to esophageal dysfunction and dense eosinophilic infiltration in the esophageal epithelium. Most affected patients in Japan are diagnosed incidentally during a medical health check-up and asymptomatic cases with typical endoscopic findings suggestive of EoE are frequently encountered. Clinical characteristics of EoE in Japanese are similar to those seen in Western populations. The predominant symptom is dysphagia, with food impaction extremely rare in Japanese cases. Linear furrows are the most frequently reported characteristic endoscopic finding, while an esophageal stricture or narrow caliber is rarely observed. Treatment strategies for EoE include drugs, dietary restrictions, and endoscopic dilation when the disease is advanced with stricture formation. Although single therapy using a proton-pump inhibitor has been shown to achieve symptomatic and histological response in the majority of patients in Japan, no prospective randomized control studies that evaluated drug or elimination diet therapy have been presented. Overall, EoE has similar clinical characteristics between Japanese and Western populations, while disease severity seems to be milder in Japan. Additional studies are necessary to determine genetic factors, natural history of the disease, and treatment efficacy of drugs and elimination diet as compared to Western populations.

Response of eosinophilic oesophagitis to proton pump inhibitors is associated with impedance-pH parameters implying anti-reflux mechanism of action

BACKGROUND

Proton pump inhibitors (PPIs) are effective therapies for eosinophilic oesophagitis (EoE), but the mechanism of action is uncertain. At on-PPI impedance-pH monitoring, improvement in oesophageal chemical clearance assessed with post-reflux swallow-induced peristaltic wave (PSPW) index characterises PPI-responsive EoE and reflux disease. Off-PPI, higher efficacy of the oesophago-salivary reflex as measured with PSPW-associated pH increments characterises PPI-responsive reflux disease and could typify PPI-responsive EoE as well.

AIM

To establish whether PPI responsiveness in EoE is associated with higher efficacy of the oesophago-salivary reflex.

METHODS

Prospective multicentre study in EoE patients investigated with impedance-pH monitoring before starting PPI. Impedance-pH parameters in PPI-responsive and PPI-refractory cases were compared. PPI response was defined histologically.

RESULTS

Considerable PSPW-associated pH increments (median 1.4 units) were found in 80 EoE patients, with significantly higher values in 48 PPI-responsive than in 32 PPI-refractory cases (1.8 vs 1.0, P = 0.02). Mucosal integrity, as measured with mean nocturnal baseline impedance was more severely impaired in the distal oesophagus in PPI-responsive cases, the gradient between mid and distal oesophagus being significantly higher (546 vs 137 Ω, P = 0.0002). PSPW-associated pH increments and the baseline impedance gradient between mid and distal oesophagus were independently associated with histological response at multivariable logistic regression; at receiver operating characteristic analysis, the area under the curve of PPI response calculated by combined assessment was 0.88.

CONCLUSION

Higher efficacy of oesophago-salivary reflex and more severe mucosal damage in the distal oesophagus are associated with EoE response to PPIs, implying an anti-reflux mechanism of action as most likely.

Dietary Management of Eosinophilic Esophagitis: Man Versus Food or Food Versus Man?

An alternative to pharmacologic management of eosinophilic esophagitis, elimination of food antigens for diet therapy is an effective first-line treatment strategy to induce and maintain symptomatic, histologic, and endoscopic disease remission. The 3 dietary strategies for eosinophilic esophagitis include elemental diet, empiric elimination diet, and targeted elimination diet. We review the studies supporting various diet therapy strategies, practical considerations and challenges for applying an elimination diet, and novel testing to identify triggers and optimize food reintroduction.

Diagnostic Value of Mid-esophageal Biopsies in Pediatric Patients With Eosinophilic Esophagitis

INTRODUCTION

Eosinophilic esophagitis (EoE) is histologically defined as the presence of 15 or more intraepithelial eosinophils per high-power fields. Limited consensus exists on where to sample the esophagus in pediatrics. This study aimed to identify whether endoscopic and histologic examination of the mid esophagus offers diagnostic value compared to proximal/distal esophageal biopsies.

METHODS

A retrospective chart review of pediatric patients with EoE was performed. Endoscopic and histologic parameters were assessed at the initial and follow-up visits, and concordance between proximal/distal biopsy and mid biopsy was determined.

RESULTS

A total of 100 patients with a mean age of 9.6 ± 4.07 years were included. Endoscopic parameters between proximal/distal and mid esophagus were concordant in 84% to 97% of patients (initial assessment) and in 80% to 97% of patients (at follow-up). Mid esophagus showed endoscopic abnormalities, which were absent at the proximal/distal esophagus in 1% to 5% of patients, as well as histologic abnormalities in 2% to 8% of patients overall at initial and follow-up examinations.

CONCLUSIONS

We recommend continued endoscopic and histologic assessment of the proximal/distal biopsy; however, examination of the mid esophagus does offer small diagnostic value in our subset of patients. Future studies need to be conducted before conclusive recommendations supporting the use of mid-esophageal biopsies can be made.

Novel and rare forms of oesophagitis

Our understanding of inflammatory diseases of the gastrointestinal tract, including those of the oesophagus, has expanded in recent years. Once attributed almost exclusively to gastro-oesophageal reflux disease or infection, it is now recognised that oesophagitis may occur due to a variety of distinct disease entities. Many of these conditions cause debilitating and persistent symptoms, impacting upon quality of life and necessitating ongoing surveillance and treatment. This review will consider the clinical, endoscopic and histopathological features of these novel and rare forms of oesophagitis.

Red Between the Lines: Evolution of Eosinophilic Esophagitis as a Distinct Clinicopathologic Syndrome

Eosinophilic esophagitis (EoE) is characterized by eosinophilic infiltration of the esophageal mucosa and symptoms of esophageal dysfunction, including dysphagia. While EoE is still considered a rare disease, in practice it seems that more and more cases are diagnosed every week, research in the field is exploding, and the pipeline for treatments contains multiple agents, some of which are quite far along the development pathway. After only scattered cases and small series were published in the late 1970s and 1980, Stephen Attwood, Thomas Smyrk, Tom DeMeester, and James Jones, published in Digestive Diseases and Sciences in 1993 a seminal report that described a clinicopathologic syndrome of esophageal eosinophilia with dysphagia. This review details the origins of this paper and compares and contrast what was observed then and what is known now about multiple aspects of EoE, including the clinical presentation, diagnosis, epidemiology, natural history, and treatments and outcomes. Moreover, it will highlight how the paper presaged a number of controversies in the field that have yet to be resolved, as well as foreshadowed the collaborative, multidisciplinary approach that has led to rapid advances.

Endoscopic and histological characteristics in patients with eosinophilic esophagitis responsive and non-responsive to proton pump inhibitors

OBJECTIVE

To compare endoscopic and histologic features of pediatric patients with eosinophilic esophagitis (EoE) responding to proton pump inhibitor (PPI) to those not responding to PPI.

METHODS

Endoscopic reports and photographs of patients with symptoms of esophageal dysfunction and ≥15 eosinophils per high-powered field (eos/hpf) in esophageal biopsies prior to PPI trial were reviewed. Patients were classified as responsive to PPI (PPIREoE) or non-responsive to PPI (PPINREoE) according to response totreatment (<15 eos/hpf) at second endoscopy after 8 weeks.

RESULTS

Of the 231 patients (72.3% male), 64 (27.7%) were responsive to the proton pump inhibitors. Edema (77.3% vs. 62.5%, p=0.031) and vertical lines (69.5% vs. 51.6%, p=0.014) were more frequent in PPINREoE patients. An eosinophil count in the mid-esophagus ≥ 35 eos/HPF (25.1% vs. 12.5%) was more frequent in these patients (p=0.001). Those with eosinophil count < 15 eos/HPF in the mid-esophagus at the first endoscopy were more likely to respond to treatment with proton pump inhibitors compared to patients with 15-34 eos/HPF (p=0.004, OR: 3.26, 95% CI: 1.46-7.24) and to patients with ≥ 35 eos/HPF (p=0.006, OR: 3.20, 95% CI: 1.39-7.41).

CONCLUSION

Edema and vertical lines at the endoscopy and a higher eosinophil count in the mid-esophagus were more frequent in patients who were non-responsive to proton pump inhibitors. As there were no significant differences in the other findings between the groups, it cannot be affirmed that these characteristics are sufficient to differentiate between PPINREoE and PPIREoE patients.

Eosinophilic esophagitis: updates on key unanswered questions

Eosinophilic esophagitis (EoE) is a clinicopathologic disease characterized by symptoms of esophageal dysfunction and esophageal eosinophilia. In the last decade, there has been a dramatic increase in its prevalence for reasons that are not completely understood. The underlying pathophysiology involves an antigen-mediated T_H 2 immune response that draws eosinophils to the esophagus, causing mucosal inflammation, esophageal remodeling, and fibrosis. This ultimately leads to esophageal dysfunction that most commonly manifests as dysphagia. In this review, we will discuss updates on key questions regarding the diagnosis and treatment of EoE.

Eosinophilic Esophagitis: Update on Diagnosis and Treatment in Pediatric Patients

Eosinophilic esophagitis (EoE) is a chronic immune-mediated inflammatory disorder characterized by symptomatic esophageal dysfunction and an eosinophil-predominant inflammation of the esophagus. EoE arises from interaction between genetic and environmental factors. In pediatric patients, clinical manifestations vary depending on age, from a gastroesophageal reflux disease (GERD)-like condition to severe dysphagic symptoms. Upper endoscopy is considered the gold standard for diagnosis and monitoring of EoE; however, significant efforts are underway to identify noninvasive diagnostic tools and biomarkers to avoid repetitive invasive procedures. Therapeutic first-line options currently available for EoE are elimination diets, proton pump inhibitors (PPIs), and steroids. The aim of treatment is to improve clinical symptoms while obtaining mucosal healing and avoiding long-term complications. Dietary treatment options comprise different empiric diets or an exclusively amino acid formula. Despite the efficacy of diets, compliance is often challenging. PPIs and topical steroids represent the main pharmacological options for EoE, and both can induce and maintain remission. Topical steroids have been reported as more effective, but data on long-term safety remain insufficient for both these and PPIs. Endoscopic dilations are currently reserved for severe untreated fibrostenotic disease unresponsive to medical therapies. Several biologic agents are available but not yet approved for EoE.

Mucosal impedance for esophageal disease: evaluating the evidence

Impedance has traditionally been employed in esophageal disease as a means to assess bolus flow and reflux episodes. Recent and ongoing research has provided new and novel applications for this technology. Measurement of esophageal mucosal impedance, via either multichannel intraluminal impedance catheters or specially designed endoscopically deployed impedance catheters, provides a marker of mucosal integrity. Mucosal impedance has been shown to segregate gastroesophageal reflux disease (GERD) and eosinophilic esophagitis from non-GERD controls and may play a role in predicting response to reflux intervention. More data are needed with regard to other esophageal subgroups, outcome studies, and functional disease. Our paper reviews the history of impedance in esophageal disease, the means of assessing baseline and mucosal impedance, data with regard to the newly developed mucosal impedance probes, the clinical utility of mucosal impedance in specific clinical conditions, and limitations in our existing knowledge, along with suggestions for future studies.

Eosinophilic Esophagitis: Existing and Upcoming Therapies in an Age of Emerging Molecular and Personalized Medicine

PURPOSE OF REVIEW

Recent research efforts have spurred great progress in the diagnosis and management of eosinophilic esophagitis (EoE). Nonetheless, challenges remain in addressing disease burden and impairment in the growing EoE population. We highlight work from the Cincinnati Center for Eosinophilic Disorders, the Consortium of Eosinophilic Gastrointestinal Disease Researchers, and others that address these ongoing challenges.

RECENT FINDINGS

New tools for characterizing EoE disease activity include the EoE Histology Scoring System (EoEHSS), endoscopic alternatives, validated patient-reported outcome (PRO) questionnaires, and investigational biomarkers. These diagnostic and monitoring strategies have been complemented by advances in EoE therapy. Treatment modalities have refined the traditional approaches of dietary elimination, swallowed steroids, and proton pump inhibitors (PPI), and biologics offer promise for future treatment. This review summarizes EoE advances in disease management and newly defined EoE endotypes that may serve as the foundation for EoE-personalized medicine.

Technical review on the management of eosinophilic esophagitis: a report from the AGA institute and the joint task force on allergy-immunology practice parameters

Eosinophilic esophagitis (EoE) is a chronic inflammatory condition of the esophagus. Many new studies have been reported recently that describe EoE management. An expert panel was convened by the American Gastroenterological Association Institute and the Joint Task Force on Allergy-Immunology Practice Parameters to provide a technical review to be used as the basis for an updated clinical guideline. This technical review was developed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Eighteen focused EoE management questions were considered, with 15 answered using the GRADE framework and 3 with a narrative summary. There is moderate certainty in the evidence that topical glucocorticosteroids effectively reduce esophageal eosinophil counts to <15 per high-power field over a short-term treatment period of 4-12 weeks, but very low certainty about the effects of using topical glucocorticosteroids as maintenance therapy. Multiple dietary strategies may be effective in reducing esophageal eosinophil counts to <15 per high-power field over a short-term treatment period, with moderate certainty for elemental diets, low certainty for empiric 2-, 4-, and 6-food elimination diets, and very low certainty that allergy-based testing dietary eliminations have a higher failure rate compared to empiric diet elimination. There is very low certainty for the effect of proton pump inhibitors in patients with esophageal eosinophilia. Although esophageal dilation appears to be relatively safe, there is no evidence that it reduces esophageal eosinophil counts. There is very low certainty in the effects of multiple other medical treatments for EoE: anti-interleukin-5 therapy, anti-interleukin-13 therapy, anti-IgE therapy, montelukast, cromolyn, and anti-TNF therapy.

Technical Review on the Management of Eosinophilic Esophagitis: A Report From the AGA Institute and the Joint Task Force on Allergy-Immunology Practice Parameters

Eosinophilic esophagitis (EoE) is a chronic inflammatory condition of the esophagus. Many new studies have been reported recently that describe EoE management. An expert panel was convened by the American Gastroenterological Association Institute and the Joint Task Force on Allergy-Immunology Practice Parameters to provide a technical review to be used as the basis for an updated clinical guideline. This technical review was developed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Eighteen focused EoE management questions were considered, with 15 answered using the GRADE framework and 3 with a narrative summary. There is moderate certainty in the evidence that topical glucocorticosteroids effectively reduce esophageal eosinophil counts to <15 per high-power field over a short-term treatment period of 4-12 weeks, but very low certainty about the effects of using topical glucocorticosteroids as maintenance therapy. Multiple dietary strategies may be effective in reducing esophageal eosinophil counts to <15 per high-power field over a short-term treatment period, with moderate certainty for elemental diets, low certainty for empiric 2-, 4-, and 6-food elimination diets, and very low certainty that allergy-based testing dietary eliminations have a higher failure rate compared to empiric diet elimination. There is very low certainty for the effect of proton pump inhibitors in patients with esophageal eosinophilia. Although esophageal dilation appears to be relatively safe, there is no evidence that it reduces esophageal eosinophil counts. There is very low certainty in the effects of multiple other medical treatments for EoE: anti-interleukin-5 therapy, anti-interleukin-13 therapy, anti-IgE therapy, montelukast, cromolyn, and anti-TNF therapy.

Eosinophilic Esophagitis in Children: Clinical Findings and Diagnostic Approach

Eosinophilic esophagitis (EoE) is an emerging chronic immune and antigen-mediated clinicopathologic disease. During the last 2 decades, the incidence of this condition in children has increased significantly, thanks to practitioners for creating the awareness and higher use of diagnostic endoscopy. We have analysed paediatric literature on EoE focusing on the epidemiology, pathophysiology, clinical findings and diagnostic approach. EoE is pathogenically related to a Th2 inflammation characterized by a mixed IgE and non-IgEmediated reaction to food and/or environmental agents. This leads to esophageal dysfunction and remodeling accompanied by subepithelial fibrosis. EoE can be presented with several range of gastrointestinal symptoms, including regurgitation, vomiting, feeding difficulties or feeding refusal in infants and toddlers, as well as heartburn, dysphagia and food bolus impaction in older children and adults. The diagnostic suspicion is based on the presence of chronic symptoms of esophgeal dysfunction and esophageal eosinophilia characterised histologically by a significant eosinophilic infiltration of the oesophageal mucosa (>15 eosinophils per high powered field). In this review, we will provide an update on clinical presentation and diagnostic approach to EoE in children. We emphasized on the relevant aspects of the new clinical condition termed "PPI responsive esophageal eosinophilia", as entities distinct from EoE and the role of PPI trial in the diagnostic workup, therefore we proposed a new diagnostic algorithm.

Eosinophilic gastrointestinal diseases - Pathogenesis, diagnosis, and treatment

Eosinophilic gastrointestinal diseases (EGIDs) are divided into eosinophilic esophagitis (EoE) and eosinophilic gastroenteritis (EGE), depending on the involved gastrointestinal tract, though both are considered to be chronic Th2-type allergic diseases caused by food or environmental allergens. In development of EoE, refluxed gastric acid may also have an important role. For diagnosis of EGIDs, the presence of symptoms possibly originating from the involved gastrointestinal tract and dense eosinophil infiltration are important factors. Imaging studies, including endoscopy and computed tomography, along with histopathological examinations of biopsy specimens are useful for diagnosis, whereas laboratory testing of blood, urine, and stool samples has limited value. Three useful options for treating EoE patients are acid inhibitors, swallowed topical corticosteroids, and an elimination diet, while systemic administration of glucocorticoids is the standard treatment of EGE, though information is limited. Since the prevalence of EGIDs is increasing in Western countries as well as Japan, development of effective treatments based on sufficient evidence is becoming an urgent need.

Clinical and Molecular Factors Associated With Histologic Response to Topical Steroid Treatment in Patients With Eosinophilic Esophagitis

BACKGROUND & AIMS

Few factors have been identified that can be used to predict response of patients with eosinophilic esophagitis (EoE) to topical steroid treatment. We aimed to determine whether baseline clinical, endoscopic, histologic, and molecular features of EoE can be used to predict histologic response.

METHODS

We collected data from 97 patients with EoE, from 2009 through 2015, treated with a topical steroid for 8 weeks; 59 patients had a histologic response to treatment. Baseline clinicopathologic features and gene expression patterns were compared between patients with a histologic response to treatment (<15 eos/hpf) and non-responders (≥15 eos/hpf). We performed sensitivity analyses for alternative histologic response definitions. Multivariate logistic regression was performed to identify predictive factors associated with response to therapy, which were assessed with area under the receiver operator characteristic (AUROC) curves.

RESULTS

Baseline dilation was the only independent predictor of non-response (odds ratio [OR], 0.30; 95% CI, 0.10-0.89). When an alternate response (<1 eos/hpf) and non-response (<50% decrease in baseline eos/hpf) definition was used, independent predictors of response status were age (OR, 1.08; 95% CI, 1.02-1.14), food allergies (OR, 12.95; 95% CI, 2.20-76.15), baseline dilation (OR, 0.17; 95% CI, 0.03-0.88), edema or decreased vascularity (OR, 0.20; 95% CI, 0.04-1.03), and hiatal hernia (OR, 0.07; 95% CI, 0.01-0.66). Using these 5 factors, we developed a predictive model that discriminated complete responders from non-responders with an AUROC of 0.88. Baseline gene expression patterns were not associated with treatment response and did not change with different histologic response thresholds.

CONCLUSIONS

In an analysis of 97 patients with EoE, we found dilation to be the only baseline factor associated with non-response to steroid treatment (<15 eos/hpf). However, a model comprising 5 clinical, endoscopic, and histologic factors identified patients with a complete response (<1 eos/hpf). A baseline gene expression panel was not predictive of treatment response at any threshold.