Working with the US Food and Drug Administration: progress and timelines in understanding and treating patients with eosinophilic esophagitis

Scientific journey to the first FDA-approved drug for eosinophilic esophagitis

When eosinophilia was first associated with esophagitis, it was thought to reflect gastroesophageal reflux disease, especially given the efficacy of reflux medications to abate esophageal eosinophilia in many individuals. Subsequent studies demonstrated disease remittance with amino acid-based formulas and conversely induction of esophageal eosinophilia in mice following allergen challenge. These results, along with the finding that proton pump inhibitors alleviated esophageal eosinophilia by an anti-inflammatory mechanism, turned attention away from an acid-induced pathogenesis and established eosinophilic esophagitis (EoE) as a separate disease entity driven by allergic inflammation. The disease underpinnings were elucidated by analysis of esophageal transcriptomic profiling, revealing gene signatures orchestrated by type 2 cytokine signaling, mainly IL-13. Preclinical studies showed that IL-13 overproduction was sufficient to induce EoE-like changes in mice and human ex vivo systems and conversely that inhibiting IL-13 signaling attenuated these processes. An early proof-of-principle study with a humanized anti-IL-13 mAb in patients with EoE revealed correction of the EoE transcriptome and attenuation of esophageal eosinophilia, providing a rationale for advancing anti-type 2 cytokine therapy for EoE. Dupilumab, a precision therapeutic mAb that blocks the shared IL-13 and IL-4 receptor, is the first drug to advance through clinical trials and receive US Food and Drug Administration approval for EoE. The ability of dupilumab to improve clinical, histologic, endoscopic, and molecular features of EoE and garner US Food and Drug Administration approval is a victory for science, rare diseases, patients, and advocacy and provides a framework for developing additional EoE treatments and approved treatments for eosinophilic gastrointestinal disease beyond the esophagus.

Treatment of eosinophlic esophagitis with swallowed topical corticosteroids

Eosinophilic esophagitis (EoE) is an emerging chronic local immune-mediated disease of the esophagus. Beside proton pump inhibitors and food-restriction-diets swallowed topical corticosteroids (STC) can be offered as a first line therapy according to current guidelines. This review describes the background and practical management of STCs in EoE. So far, mainly asthma inhalers containing either budesonide or fluticasone have been administered to the esophagus by swallowing these medications “off label”. Recently esophagus-targeted formulations of topical steroids have been developed showing clinicopathological response rates up to 85% - an orodispersible tablet of budesonide has been approved as the first “in label” medication for EoE in Europe in June 2018. Whereas it was shown that disease remission induction of EoE by STCs is highly effective, there is still a lack of data regarding long-term and maintenance therapy. However, current studies on STC maintenance therapy add some movement into the game.

Advancing patient care through the Consortium of Eosinophilic Gastrointestinal Disease Researchers (CEGIR)

Recent advances in rare disease research are accelerated by the work of consortia that have been supported by the National Institutes of Health. Development of such consortia rely on multidisciplinary relationships and engagement with patient advocacy groups, as well as the National Institutes of Health and industry and academic partners. In this rostrum we present the development of such a process that focuses on eosinophilic gastrointestinal diseases. Principal investigators, patient advocacy groups, research assistants, and trainees work together to perform natural history studies that promote clinical trial readiness tools, conduct clinical trials, train a new generation of investigators, and perform innovative pilot studies.

A Conceptual Approach to Understanding Treatment Response in Eosinophilic Esophagitis

While the diagnosis and initial treatment of eosinophilic esophagitis are becoming more standardized, there are still major gaps in knowledge related to measuring treatment response. One such question centers on how to measure treatment response and what treatment endpoints should be. This impacts not only patient care and engagement in decision-making, but also the field of drug development. In addition, studies so far have use a myriad of treatment endpoints including over a dozen histologic endpoint criteria. This review will discuss the various stakeholders involved in assessment of treatment endpoints of a complex condition, including patients, practitioners and regulatory agencies, and the care settings in which treatment response is assessed, including routine clinical care, clinical trials, and observational studies. Potential parameters or treatment endpoints such as histology, symptoms, patient-reported outcomes, endoscopy, and biomarkers are discussed along with associated challenges and opportunities. A framework on how to define treatment outcomes is discussed and a conceptual approach treatment response is proposed. This takes into account histology, symptoms, and endoscopic findings and harnesses existing, validated tools. It includes definitions of nonresponse, complete normalization, and a graded response category between these 2 extremes, and also permits flexibility and latitude for modifications as newer knowledge emerges. In addition, ways to position the pediatric population in these endeavors are discussed as are future research directions.

Preliminary psychometric analyses and clinical performance of a caregiver self-efficacy scale for food allergy self-management

BACKGROUND

Food allergy health-related quality of life has been defined, but self-efficacy is poorly described.

OBJECTIVE

To examine the preliminary reliability, validity, and clinical performance of a novel food allergy self-efficacy index.

METHODS

An 8-item Food Allergy Self-Efficacy Questionnaire (FASEQ) was adapted for food allergy-related themes and coadministered with the Food Allergy Quality of Life Parental Burden (FAQL-PB) index to caregivers self-reporting a food allergic child (group A) and those with children followed up at a food allergy referral center clinic (group B). FASEQ split-half reliability, 2-week recall, factor analysis, and construct and discriminative validity were assessed. Multiple linear regression was used to explore predictive associations between the FAQL-PB and the FASEQ.

RESULTS

Among 2,308 caregivers, the mean FASEQ score was 2.69 (95% CI, 2.66-2.73) and was lower (better) among group A (mean FASEQ score, 2.52; 95% CI, 2.49-2.56) vs group B (mean FASEQ score, 3.75; 95% CI, 3.66-3.84; P < .001). The FASEQ Cronbach α was 0.87, and the 2-week intraclass correlation coefficient (ICC) was 0.75. Total and 6 of 8 individual FASEQ domain scores were significantly lower among caregivers with children having anaphylaxis or epinephrine use vs none and peanut or tree nut allergy vs milk or egg allergy, demonstrating good discriminative validity. Total FASEQ score was associated with FAQL-PB score (ICC, 0.13; 95% CI, 0.06-0.19; P < .001), with 6 of 8 FASEQ individual domains significantly associated (ICC range, -0.17 to 0.3; P < .01 for all). Factor analysis revealed 2 domains (medical care and social functioning) with construct validity.

CONCLUSION

We present preliminary evidence the FASEQ is a valid tool to assess caregiver food allergy self-efficacy. Self-efficacy is a distinct but related concept that captures aspects of self-management that are an important companion to health-related quality of life.

Heterogeneity in Clinical, Endoscopic, and Histologic Outcome Measures and Placebo Response Rates in Clinical Trials of Eosinophilic Esophagitis: A Systematic Review

BACKGROUND & AIMS

Agents are being developed for treatment of eosinophilic esophagitis (EoE). However, it is not clear what outcome measures would best determine the efficacy and safety of these agents in clinical trials. We performed a systematic review of outcomes used in randomized placebo-controlled trials of EoE and we estimate the placebo response and rates of remission.

METHODS

We searched MEDLINE, Embase, CENTRAL, ClinicalTrials.gov, and the EU Clinical Trials Register from inception through February 20, 2018 for randomized controlled trials of pharmacologic therapies for EoE. Efficacy outcome definitions, measurement tools, and the proportion of patients responding to placebo were collected and stratified by based on histologic, endoscopic, and patient-reported outcomes.

RESULTS

We analyzed data from 22 placebo-controlled trials, comprising 1112 patients with EoE. Ten additional active registered trials were identified. Most published trials evaluated topical corticosteroid therapy (13/22, 59.1%). Histologic outcomes measuring eosinophil density and patient-reported outcomes were reported in 21/22 published trials (95.5%). No consistently applied definitions of histologic or patient-reported response or remission were identified. Endoscopic outcomes were described in 60% (12/20) of published trials. The EoE Endoscopic Reference Score is the most commonly applied tool for describing changes in endoscopic appearance. The median histologic response to placebo was 3.7% (range, 0%-31.6%) and the median rate of remission in patients given placebo was 0.0% (range, 0%-11.0%). The median patient-reported response to placebo was 14.4% (range, 8.6%-77.8%) and rate of remission in patients given placebo was 26.2% (range, 13.2%-35.7%).

CONCLUSIONS

In a systematic review of the literature, we found that no standardized definitions of histologic, endoscopic, or patient-reported outcomes are used to determine whether pharmacologic agents produce a response or remission in patients with EoE. A core outcome set is needed to reduce heterogeneity in outcome reporting and facilitate trial interpretation and comparison of results from trials.

Prospective assessment of disease-specific quality of life in adults with eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is an important cause of upper gastrointestinal dysfunction in children and adults. The EoE-quality of life (QOL)-A was validated as a disease-specific measure of quality of life in EoE. This study characterized the extent of QOL concerns in a cohort of adult EoE patients and delineated the relationships between QOL and other disease activity measures. One hundred sixty-seven patients enrolled in this prospective cohort study. Patients with established and suspected EoE undergoing endoscopy at a single university-based medical center were recruited. EoE was diagnosed on the basis of the clinical criteria and histologic demonstration of ≥15 eos/hpf while on proton pump inhibition therapy. Sixty five patients undergoing repeat endoscopy during the enrollment period participated twice. Patients provided demographic information and completed symptom assessments and the EoE-QOL-A. Analyses included comparisons with overall QOL as well as QOL subscales. Outcome measures included endoscopic activity using a validated instrument, the EoE Endoscopic Reference Score, and histology. Overall QOL was significantly correlated with dysphagia frequency, intensity, and severity (P < 0.001). Patients who experienced a food impaction in the last 30 days had significantly worse overall QOL (P = 0.009). There was no correlation between overall QOL and years since diagnosis, symptom duration, endoscopic features, or histologic findings. Patient symptoms correlated with endoscopic features of edema, rings, and stricture severity. Histologic activity was highly correlated with severity of endoscopic features. Patients who underwent repeat endoscopy with histologic response demonstrated improved eating and social QOL; however, overall QOL was unchanged. In adults with EoE, patient reported QOL is associated with symptom severity but not endoscopic or histologic features. Disease-specific QOL may complement parameters of biologic activity in the assessment of overall disease burden in EoE.

Compounded Oral Viscous Budesonide is Effective and Provides a Durable Response in Eosinophilic Esophagitis

AIM

Because no approved medications exist for eosinophilic esophagitis (EoE), patients must use off-label drugs or create their own formulations. We assessed the efficacy of a standardized compounded budesonide suspension for treatment of EoE.

MATERIALS AND METHODS

We conducted a retrospective cohort study of EoE patients at the University of North Carolina treated with compounded budesonide dispensed by a specialty compounding pharmacy. Outcomes (symptomatic global response [yes/no], endoscopic response [% with individual findings], and histologic response [absolute eosinophil count; % with <15 eos/hpf])were assessed after the initial and last treatment in our system.

RESULTS

We identified 48 patients treated with compounded budesonide (mean age 33.6; 69% male; 96% white; 2.4 mg mean initial dose). After a mean length of follow-up of 17.0 months (range: 4.2 - 56.3), there was a significant decrease in symptoms of dysphagia (95% vs. 32%, p < 0.001), improvements in heartburn (37% vs. 11%, p=0.06) and global symptom response (81%). The median of the peak eosinophil counts decreased from 55 to 20 eos/hpf (p<0.001) with 42% achieving a response of <15 eos/hpf. Esophageal candidiasis was rare (6%). In the 18 patients with prior non-response to corticosteroids or dietary elimination, 83% had symptomatic and 38% had histologic response.

CONCLUSION

Compounded budesonide suspension produced a durable symptomatic, endoscopic, and histologic response in a cohort followed for more than a year. Many patients previously refractory to prior therapy responded to compounded budesonide. This formulation can be used clinically until there are approved drugs with esophageal formulations for EoE.

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.

White Paper AGA: Drug Development for Eosinophilic Esophagitis

Since first characterized in 2 small case series in the early 1990s, eosinophilic esophagitis (EoE) has emerged as a commonly identified cause of esophageal symptoms in children and adults.1,2 Although several highly effectively dietary, pharmacologic, and endoscopic therapies have been reported, none is currently approved by either the US Food and Drug Administration (FDA) or European regulatory authorities. Evolving diagnostic criteria have challenged drug development, in particular the recognition of complex interactions with the most prevalent esophageal disorder, gastroesophageal reflux disease (GERD). Heterogeneity in the clinical presentations of affected children and adults has created difficulties with uniform inclusion criteria and the development of disease-specific, patient-reported outcome (PRO) instruments. Furthermore, controversies regarding the appropriate therapeutic endpoints of EoE have impeded the design of clinical trials. Despite these obstacles, collaborative efforts by investigators, industry, the FDA, and patient advocacy groups have resulted in substantial progress in drug development in EoE over the past 2 decades.3 The purpose of this article is to summarize discussions on EoE based on the 2016 Drug Development Conference sponsored by the Center for Diagnostics and Therapeutics of the American Gastroenterological Association.

Filaggrin and Periostin Expression Is Altered in Eosinophilic Esophagitis and Normalized With Treatment

OBJECTIVES

Previous data have suggested that filaggrin (FLG) and periostin (POSTN) genes may be dysregulated in eosinophilic esophagitis (EoE). We aimed to further evaluate the expression patterns of FLG and POSTN proteins in esophageal tissue samples of patients with EoE, as compared to those of patients with gastroesophageal reflux disease (GERD) and normal controls.

METHODS

A total of 61 prospectively collected cases, including 40 children with EoE and 21 children with GERD, and a control group of 14 sex- and age-matched healthy children were enrolled. Patients with EoE were treated with skin testing-driven elimination diet and/or corticosteroids. The immunohistochemical expression of FLG and POSTN was evaluated in esophageal biopsies obtained from patients and controls, and the results were correlated with EoE-related clinicopathological parameters.

RESULTS

Positive FLG and negative POSTN staining were observed in all esophageal biopsies from normal controls. In contrast, FLG and POSTN stained negative and positive, respectively, in all pretreatment biopsies obtained from patients with EoE, whereas FLG and POSTN stained positive in 57.1% and 95.2% of GERD cases, respectively (P < 0.001). A statistically significant decrease of the proportion of cases with negative FLG and positive POSTN staining was observed from the first (pretreatment) to the second (post-treatment) biopsy in the subgroup of patients with EoE (P < 0.001 in both correlations).

CONCLUSIONS

FLG and POSTN expression may be downregulated and upregulated, respectively, in the esophageal mucosa of patients with active EoE, and these changes may be restored with treatment in a significant percentage of cases.

Budesonide Oral Suspension Improves Symptomatic, Endoscopic, and Histologic Parameters Compared With Placebo in Patients With Eosinophilic Esophagitis

BACKGROUND & AIMS

Pharmacologic treatment of eosinophilic esophagitis (EoE) is limited to off-label use of corticosteroids not optimized for esophageal delivery. We performed a randomized, controlled phase 2 trial to assess the ability of budesonide oral suspension (BOS), a novel muco-adherent topical steroid formulation, to reduce symptoms and esophageal eosinophilia in adolescents and adults with EoE.

METHODS

In this multicenter, randomized, double-blind, placebo-controlled, parallel-group trial, 93 EoE patients between the ages of 11 and 40 years with dysphagia and active esophageal eosinophilia were randomized to receive either BOS 2 mg or placebo twice daily for 12 weeks. Co-primary outcomes were change in Dysphagia Symptom Questionnaire (DSQ) score from baseline, and proportion of patients with a histologic response (≤6 eosinophils/high-power field) after treatment. Endoscopic severity scores and safety parameters were assessed.

RESULTS

At baseline, mean DSQ scores were 29.3 and 29.0, and mean peak eosinophil counts were 156 and 130 per hpf in the BOS and placebo groups, respectively. After treatment, DSQ scores were 15.0 and 21.5, and mean peak eosinophil counts were 39 and 113 per high-power field, respectively (P < .05 for all). For BOS vs placebo, change in DSQ score was -14.3 vs -7.5 (P = .0096), histologic response rates were 39% vs 3% (P < .0001), and change in endoscopic severity score was -3.8 vs 0.4 (P < .0001). Adverse events were similar between groups.

CONCLUSIONS

Treatment with BOS was well tolerated in adolescent and young adult patients with EoE and resulted in improvement in symptomatic, endoscopic, and histologic parameters using validated outcome instruments. ClinicalTrials.gov ID NCT01642212.

Eosinophilic Esophagitis: A Comprehensive Review

Eosinophilic esophagitis (EoE) is an emerging chronic atopic clinical-pathologic disease with an estimated prevalence of 1/1000 similar to the one of Crohn's diseases. Usually, EoE is firstly suspected due to symptoms that are caused by esophageal dysfunction and/or fibrosis. EoE diagnosis is confirmed if the esophageal biopsy shows at least 15 eosinophils per high power field (eos/hpf) as a peak value in one or more of at least four specimens obtained randomly from the esophagus. Most of the patients affected by EoE have other atopic diseases such as allergic rhinitis, asthma, IgE-mediated food allergies, and/or atopic dermatitis. The local inflammation is a T helper type 2 (Th2) flogosis, which most likely is driven by a mixed IgE and non-IgE-mediated reaction to food and/or environmental allergens. Recently published genetic studies showed also that EoE is associated with single nucleotide polymorphism (SNP) on genes which are important in atopic inflammation such as thymic stromal lymphopoietin (TSLP) located close to the Th2 cytokine cluster (IL-4, IL-5, IL-13) on chromosome 5q22. When the EoE diagnosis is made, it is imperative to control the local eosinophilic inflammation not only to give symptomatic relief to the patient but also to prevent complications such as esophageal stricture and food impaction. EoE is treated like many other atopic diseases with a combination of topical steroids and/or food antigen avoidance.

How to measure disease activity in eosinophilic esophagitis

Activity of Eosinophilic Esophagitis (EoE) can be measured by patient reported outcomes (symptoms and quality of life) and clinician-reported outcomes (endoscopic, histologic, or biochemical alterations). Over the last years efforts have been underway to develop and validate instruments to assess EoE activity in the different domains. Such instruments are urgently needed to standardize the language of EoE activity assessment and, in so doing, to facilitate communication among various stakeholders. Such standardization will ultimately allow EoE researchers to define meaningful endpoints for use in clinical trials and observational studies, to compare the efficacy of different therapeutic modalities, and to develop algorithms in order to provide patients with the appropriate therapy. This review provides an overview of the current status of instruments that assess EoE activity in the different domains.

Systematic review of outcome measures in pediatric eosinophilic esophagitis treatment trials

Background

Heterogeneity has been noted in the selection and reporting of disease-specific, pediatric outcomes in randomized controlled trials (RCTs). The consequence is invalid results or difficulty comparing results across trials. The primary objective of this systematic review was to assess primary outcome and outcome measure selection and reporting, in pediatric eosinophilic esophagitis (EoE) treatment trials. As secondary objectives, we compared trial disease definition to established concensus guidelines, and the efficacy of current EoE treatments.

Methods

We searched MEDLINE, EMBASE, The Cochrane Library, Cochrane Central Register of Controlled Trials (CENTRAL), and CINAHL since 2001. We also searched clinical trial registries (portal.nihr.ac.uk; clinicaltrials.gov; isrctn.com; and anzctr.org.au) and references of included studies. We included RCTs of EoE treatment in patients 0–18 years. Two authors independently assessed articles.

Results

Eleven studies met inclusion criteria. All identified primary outcomes, however, of 9 unique primary outcomes, only 2 were used in more than one study. In total, 25 unique primary and secondary outcome measures were employed for pediatric EoE treatment trials. Measurement properties and rationale for their selection was rarely provided. Uptake of consensus-based diagnostic criteria was 25 % in trials initiated after 2011. Due to the small number and heterogeneity of studies obtained, no meta-analysis of treatment efficacy could be undertaken. This SR was limited to exclusively pediatric RCTs.

Conclusions

The results of this study confirm the need for a standardized set of core outcomes that are universally reported in pediatric EoE trials. Consistent disease definition and standardized outcome reporting will facilitate meta-analyses across similar trials and inform future clinical decision-making.

Systematic review registration number CRD42013003798

Swallowed Fluticasone Propionate Is an Effective Long-Term Maintenance Therapy for Children With Eosinophilic Esophagitis

OBJECTIVES

Although effective in the treatment of eosinophilic esophagitis (EoE) in children, limited data exist on long-term safety and efficacy of swallowed topical corticosteroids. We investigated whether long-term use of swallowed fluticasone in children with EoE leads to sustained reduction in esophageal eosinophils, and endoscopic and clinical improvement.

METHODS

In an open-label, prospective, single-center study, we offered pediatric patients with active EoE fluticasone 2 puffs to swallow twice a day (strengths in μg/puff: 2-4 years: 44, 5-11 years: 110, ≥12 years: 220). Clinical, endoscopic, and histological assessments were performed at baseline and shortly after therapy. If histological remission was seen, fluticasone was continued with clinical follow-ups every 4 months and endoscopic and histological follow-ups yearly. Clinical scores were derived from eight symptoms (abdominal pain, nausea, vomiting, regurgitation, chest pain, dysphagia, food impaction, and early satiety). Endoscopic scores were derived from six features (rings, exudates, furrows, edema, stricture, and shearing). Scores were expressed as ratio (features present/total). In addition to peak eosinophils/high power field (HPF) (primary outcome), histological features (eosinophilic microabscesses, degranulation, superficial layering, basal zone hyperplasia, dilated intercellular spaces, and lamina propria fibrosis) were assessed. Median clinical and endoscopic scores and individual histologic features were compared over 4 time intervals: <4 months, 4-12 months, 13-24 months, and >24 months. Growth and adverse effects were monitored.

RESULTS

We enrolled 54 patients, 80% male, median age 6.5 years (range 2-17 years), 85% atopic (57% asthma, 68% allergic rhinitis, and 31% atopic dermatitis), and 74% with food allergy. Mean follow-up was 20.4 months, the longest being 68 months (5.7 years). Esophageal eosinophil counts significantly decreased (median peak eosinophils/HPF at baseline 72, <4 months: 0.5, 4-12 months: 1.75, 13-24 months: 10, and >24 months: 12, all P<0.01). All histological features significantly decreased from baseline to all follow-up time points (all P<0.01). Lamina propria fibrosis significantly decreased (% patients with fibrosis at baseline 92, <4 months: 41, 4-12 months: 50, 13-24 months: 45, and >24 months: 39, all P<0.01). Endoscopic features improved (score at baseline 0.37, <4 months: 0.17, 4-12 months: 0.17, 13-24 months: 0, and >24 months: 0.1, all P<0.01, except at >24 months: P<0.05). Symptoms improved (score at baseline 0.22, <4 months: 0, 4-12 months: 0.11, 13-24 months: 0.11, and >24 months: 0.11, all P<0.05 except at >24 months: P=0.05). In a mixed linear regression model that accounts for correlation of repeated observations in the patient in a per-patient analysis, we found that treatment with swallowed fluticasone led to a statistically significant and sustained decrease in peak esophageal eosinophil counts. Asymptomatic esophageal candidiasis was seen in three children but resolved with anti-fungal therapy. Height and weight z-scores followed expected growth curves.

CONCLUSIONS

We demonstrate that swallowed fluticasone is effective as a long-term maintenance therapy for children with EoE, without growth impediment or serious side effects.

From genetics to treatment of eosinophilic esophagitis

PURPOSE OF REVIEW

Eosinophilic Esophagitis (EoE) is an emerging chronic atopic disease. Recent advances in understanding its genetic and molecular biology pathogenesis may lead to a better management of the disease

RECENT FINDINGS

EoE is an atopic disease. Most of the patients affected by EoE have other atopic diseases such as allergic rhinitis, asthma, IgE-mediated food allergies and/or atopic dermatitis. The local inflammation is a T helper type 2 (Th2) flogosis, which most likely is driven by a mixed IgE and n-IgE-mediated reaction to food and/or environmental allergens. Epidemiological studies show that EoE is an atopic disease with a strong genetic component. Genetic studies have shown that EoE is associated with single nucleotide polymorphism on genes, which are released by the epithelium and important in atopic inflammation such as thymic stromal lymphopoietin located (TSLP) close to the Th2 cytokine cluster [interleukin (IL)-4, IL-5, IL-13] on chromosome 5q22, Calpain 14, EMSY, and Eotaxin3. When the EoE diagnosis is made, it is imperative to control the local eosinophilic inflammation not only to give symptomatic relief to the patient, but also to prevent complications such as esophageal stricture and food impaction.

SUMMARY

EoE is treated like many other atopic diseases with a combination of topical steroids and/or food antigen avoidance. The new understanding of EoE may lead to more specific and definitive treatments of EoE.

Symptoms Have Modest Accuracy in Detecting Endoscopic and Histologic Remission in Adults With Eosinophilic Esophagitis

BACKGROUND & AIMS

It is not clear whether symptoms alone can be used to estimate the biologic activity of eosinophilic esophagitis (EoE). We aimed to evaluate whether symptoms can be used to identify patients with endoscopic and histologic features of remission.

METHODS

Between April 2011 and June 2014, we performed a prospective, observational study and recruited 269 consecutive adults with EoE (67% male; median age, 39 years old) in Switzerland and the United States. Patients first completed the validated symptom-based EoE activity index patient-reported outcome instrument and then underwent esophagogastroduodenoscopy with esophageal biopsy collection. Endoscopic and histologic findings were evaluated with a validated grading system and standardized instrument, respectively. Clinical remission was defined as symptom score <20 (range, 0-100); histologic remission was defined as a peak count of <20 eosinophils/mm(2) in a high-power field (corresponds to approximately <5 eosinophils/median high-power field); and endoscopic remission as absence of white exudates, moderate or severe rings, strictures, or combination of furrows and edema. We used receiver operating characteristic analysis to determine the best symptom score cutoff values for detection of remission.

RESULTS

Of the study subjects, 111 were in clinical remission (41.3%), 79 were in endoscopic remission (29.7%), and 75 were in histologic remission (27.9%). When the symptom score was used as a continuous variable, patients in endoscopic, histologic, and combined (endoscopic and histologic remission) remission were detected with area under the curve values of 0.67, 0.60, and 0.67, respectively. A symptom score of 20 identified patients in endoscopic remission with 65.1% accuracy and histologic remission with 62.1% accuracy; a symptom score of 15 identified patients with both types of remission with 67.7% accuracy.

CONCLUSIONS

In patients with EoE, endoscopic or histologic remission can be identified with only modest accuracy based on symptoms alone. At any given time, physicians cannot rely on lack of symptoms to make assumptions about lack of biologic disease activity in adults with EoE. ClinicalTrials.gov, Number: NCT00939263.

Eosinophilic Esophagitis and Gastroenteritis

Eosinophilic gastrointestinal disease (EGID) can be classified as eosinophilic esophagitis (EoE) when the eosinophilia is limited to the esophagus or as eosinophilic gastritis (EG) if it is limited to the gastric tract, eosinophilic colitis (EC) if it is limited to the colon, and eosinophilic gastroenteritis (EGE) if the eosinophilia involves one or more parts of the gastrointestinal tract. EoE is by far the most common EGID. It is a well-defined chronic atopic disease due to a T helper type 2 (Th2) inflammation triggered often by food allergens. EoE diagnosis is done if an esophageal biopsy shows at least 15 eosinophils per high power field (eos/hpf). Globally accepted long-term therapies for EoE are the use of swallowed inhaled steroids or food antigen avoidance. The treatment of EoE is done not only to control symptoms but also to prevent complications such as esophageal stricture and food impaction. EGE cause non-specific gastrointestinal (GI) symptoms and are diagnosed if esophagogastroduodenoscopy (EGD)/colonoscopy show eosinophilia in one or more parts of the GI tract. They are rare diseases with an unclear pathogenesis, and they are poorly defined in terms of diagnostic criteria and treatment. Before initiating treatment of any EGE, it is imperative to conduct a differential diagnosis to exclude other causes of hypereosinophilia with GI localization. EGE are often poorly responsive to therapy and there is no commonly accepted long-term treatment. EG has many characteristics similar to EoE, including the fact that it is often due to a food allergen-driven Th2 inflammation; transcriptome analysis however shows that it is more a systemic disease and has a different gene signature than EoE. EC is a benign form of delayed food allergy in infant and is instead a difficult-to-treat severe inflammatory condition in older children and adults. EC in the latter groups can be a manifestation of drug allergy or autoimmune disease. Overall EGE, EC, and EG are rare and are a diagnosis of exclusion until more common causes of eosinophilia have been excluded.

Eosinophilic oesophagitis: relationship of quality of life with clinical, endoscopic and histological activity

BACKGROUND

Knowledge about determinants of quality of life (QoL) in eosinophilic oesophagitis (EoO) patients helps to identify patients at risk of experiencing poor QoL and to tailor therapeutic interventions accordingly.

AIM

To evaluate the impact of symptom severity, endoscopic and histological activity on EoE-specific QoL in adult EoE patients.

METHODS

Ninety-eight adult EoE patients were prospectively included (64% male, median age 39 years). Patients completed two validated instruments to assess EoE-specific QoL (EoO-QoL-A) and symptom severity (adult EoE activity index patient-reported outcome) and then underwent esophagogastroduodenoscopy with biopsy sampling. Physicians reported standardised information on EoE-associated endoscopic and histological alterations. The Spearman's rank correlation coefficient was calculated to determine the relationship between QoL and symptom severity. Linear regression and analysis of variance was used to quantify the extent to which variations in severity of EoE symptoms, endoscopic and histological findings explain variations in QoL.

RESULTS

Quality of life strongly correlated with symptom severity (r = 0.610, P < 0.001). While the variation in severity of symptoms, endoscopic and histological findings alone explained 38%, 35% and 22% of the variability in EoE-related QoL, respectively, these together explained 60% of variation. Symptom severity explained 18-35% of the variation in each of the five QoL subscale scores.

CONCLUSIONS

Eosinophilic oesophagitis symptom severity and biological disease activity determine QoL in adult patients with eosinophilic oesophagitis. Therefore, reduction in both eosinophilic oesophagitis symptoms as well as biological disease activity is essential for improvement of QoL in adult patients. Clinicaltrials.gov number, NCT00939263.

Pediatric Eosinophilic Esophagitis Symptom Scores (PEESS v2.0) identify histologic and molecular correlates of the key clinical features of disease

BACKGROUND

The Pediatric Eosinophilic Esophagitis Symptom Score (PEESS v2.0) measures patient-relevant outcomes. However, whether patient-identified domains (dysphagia, gastroesophageal reflux disease [GERD], nausea/vomiting, and pain) align with clinical symptomology and histopathologic and molecular features of eosinophilic esophagitis (EoE) is unclear.

OBJECTIVE

The purpose of this study was to determine whether clinical features of EoE, measured through PEESS v2.0, associate with histopathologic and molecular features of EoE. This represents a novel approach for analysis of allergic diseases, given the availability of allergic tissue biopsy specimens.

METHODS

We systematically recruited treated and untreated pediatric patients with EoE (aged 2-18 years) and examined parent proxy-reported symptoms using the PEESS v2.0. Clinical symptomology was collected by questionnaire. Esophageal biopsy samples were quantified for levels of eosinophils, eosinophil peroxidase (EPX) immunohistochemical staining, and mast cells. Molecular features were assessed by using the EoE Diagnostic Panel (94 EoE-related gene transcripts). Associations between domain scores and clinical symptoms and biological features were analyzed with Wilcoxon rank sum and Spearman correlation.

RESULTS

The PEESS v2.0 domains correlated to specific parent-reported symptoms: dysphagia (P = .0012), GERD (P = .0001), and nausea/vomiting (P < .0001). Pain correlated with multiple symptoms (P < .0005). Dysphagia correlated most strongly with overall histopathology, particularly in the proximal esophagus (P ≤ .0049). Markers of esophageal activity (EPX) were significantly associated with dysphagia (strongest r = 0.37, P = .02). Eosinophil levels were more associated with pain (r = 0.27, P = .06) than dysphagia (r = 0.24, P = .13). The dysphagia domain correlated most with esophageal gene transcript levels, predominantly with mast cell-specific genes.

CONCLUSION

We have (1) established a validated, parent proxy-reported measure for pediatric EoE, the PEESS v2.0; (2) verified that the parent proxy effectively captures symptoms; (3) determined that the dysphagia domain most closely aligns with symptoms and tissue-based molecular biomarkers; (4) established that symptoms correlate with EPX staining; and (5) observed association between mast cells and dysphagia.

How do gastroenterologists assess overall activity of eosinophilic esophagitis in adult patients?

OBJECTIVES

There is no "gold standard" for assessing disease activity in patients with eosinophilic esophagitis (EoE). We aimed to compare physicians' judgment of EoE activity with patients' judgment of symptom severity. We also aimed to examine the relative contribution of symptoms as well as endoscopic and histologic findings in shaping physicians' judgment of EoE activity.

METHODS

Six gastroenterologists (all EoE experts) assessed EoE-associated symptoms in adult patients. Patients completed a symptom instrument and provided global assessment of EoE symptom severity (PatGA) (Likert scale: 0 (inactive) to 10 (most active)). Following esophagogastroduodenoscopy with biopsy sampling, gastroenterologists provided a global assessment of EoE activity (PhysGA) (Likert scale from 0 to 10) based on patient history and endoscopic and histologic findings. Linear regression and analysis of variance was used to quantify the extent to which variations in severity of EoE symptoms and endoscopic and histologic findings explain variations in PhysGA.

RESULTS

A total of 149 EoE patients were prospectively included (71.8% male, median age at inclusion 38 years, 71.8% with concomitant allergies). A moderate positive correlation between PhysGA and PatGA (rho=0.442, P<0.001) was observed and the mean difference in the Bland-Altman plot was 1.77. Variations in severity of endoscopic findings, symptoms, and histologic findings alone explained 53%, 49%, and 30%, of the variability in PhysGA, respectively. Together, these findings explained 75% of variability in PhysGA.

CONCLUSIONS

Gastroenterologists rate EoE activity mainly on the basis of endoscopic findings and symptoms and, to a lesser extent, on histologic findings.

Efficacy and safety of oral budesonide suspension in pediatric patients with eosinophilic esophagitis

BACKGROUND & AIMS

No treatment has been approved by the U.S. Food and Drug Administration for eosinophilic esophagitis (EoE). We investigated the efficacy and safety of a new formulation of oral budesonide suspension (OBS), a corticosteroid, in a prospective, placebo-controlled, dose-ranging study.

METHODS

Subjects 2-18 years old with symptoms of EoE and peak eosinophil counts ≥20/high-power field at ≥2 levels of the esophagus were randomly assigned to groups given placebo or low-dose, medium-dose, or high-dose OBS for 12 weeks. Doses and volumes were adjusted on the basis of patients' age to cover the entire esophagus. The primary efficacy end point was compound response to therapy (peak eosinophil counts ≤6/high-power field at all levels of the esophagus and ≥50% reduction in EoE symptom score). Multiple safety parameters were evaluated.

RESULTS

Data from 71 subjects who completed all efficacy assessments were included in the primary efficacy analysis. At the end of 12 weeks, there were significantly greater percentages of responders in groups given medium-dose OBS (52.6%, P = .0092) and high-dose OBS (47.1%, P = .0174) than in the group given placebo (5.6%); there was no significant difference in percentages of responders between the low-dose OBS (11.8%) and placebo groups (P = .5282). The significant compound responses noted in the medium-dose and high-dose OBS groups were accounted for by the significant histologic responses; in contrast, all 4 groups (including the placebo group) had large symptom responses, and there was no significant difference in the percentage of subjects with a symptom response in either OBS group compared with the placebo group (P ≥ .1235). There were no unexpected safety concerns or signals.

CONCLUSIONS

Peak eosinophil counts were significantly reduced throughout the esophagus in pediatric patients with EoE who were given medium-dose and high-dose OBS. There was a large symptom response to placebo that was similar to symptom responses in the OBS groups; symptom response did not distinguish OBS from placebo. ClinicalTrials.gov number, NCT00762073.

Differential diagnosis of food protein-induced enterocolitis syndrome

Purpose of review

To assess all the possible differential diagnosis of food protein-induced enterocolitis syndrome (FPIES), both in acute and chronic presentation, reviewing the data reported in published studies.

Recent findings

There is an increase of reported cases of FPIES in recent years. As the disease presents with nonspecific symptoms, it can be misunderstood in many ways. The differential diagnosis includes, in acute presentations, the following: sepsis, other infectious diseases, acute gastrointestinal episodes, surgical emergencies, food allergies. In its chronic forms, FPIES may mimic malabsorption syndromes, metabolic disorders, primary immunodeficiencies, neurological conditions, coagulation defects, and other types of non-IgE-mediated food allergy.

Summary

A thorough clinical evaluation, including symptoms, signs, and laboratory findings, is necessary to lead the clinicians toward the diagnosis of FPIES. The major reason for delayed diagnosis appears to be the lack of knowledge of the disease.

Genome-wide association analysis of eosinophilic esophagitis provides insight into the tissue specificity of this allergic disease

Eosinophilic esophagitis (EoE) is a chronic inflammatory disorder associated with allergic hypersensitivity to food. We interrogated >1.5 million genetic variants in EoE cases of European ancestry and subsequently in a multi-site cohort with local and out-of-study control subjects. In addition to replicating association of the 5q22 locus (meta-analysis P=1.9×10(-16)), we identified an association at 2p23 spanning CAPN14 (P=2.5×10(-10)). CAPN14 was specifically expressed in the esophagus, was dynamically upregulated as a function of disease activity and genetic haplotype and after exposure of epithelial cells to interleukin (IL)-13, and was located in an epigenetic hotspot modified by IL-13. Genes neighboring the top 208 EoE-associated sequence variants were enriched for esophageal expression, and multiple loci for allergic sensitization were associated with EoE susceptibility (4.8×10(-2) Collapse

Key Words Collapse

MESH Headings

• Adolescent
• Adult
• Calpain/genetics
• Child
• Child, Preschool
• Eosinophilic Esophagitis/genetics
• Epithelial Cells/metabolism
• Esophagus/metabolism
• Female
• Genetic Predisposition to Disease
• Genetic Variation
• Genome-Wide Association Study/methods
• Genotype
• Haplotypes
• Humans
• Interleukin-13/genetics
• Male
• Meta-Analysis as Topic
• Middle Aged
• Models, Genetic
• Organ Specificity/genetics
• Up-Regulation
• Young Adult

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Grants

• U01 AI066560 NIAID NIH HHS
• U01 HG006828-S1 NHGRI NIH HHS
• T32 AI060515 NIAID NIH HHS
• P30 DK078392 NIDDK NIH HHS
• UL1 TR-000067 NCATS NIH HHS
• T32 HL7752-19 NHLBI NIH HHS
• T32 HL007752 NHLBI NIH HHS
• UL1 TR-000039 NCATS NIH HHS
• P01 AI083194 NIAID NIH HHS
• UL1 TR-000083 NCATS NIH HHS
• UL1 TR-000424 NCATS NIH HHS
• U01 HG006828-S2 NHGRI NIH HHS
• T32 GM063483 NIGMS NIH HHS
• U01 HG006828 NHGRI NIH HHS
• U19 AI066738 NIAID NIH HHS
• R37 AI024717 NIAID NIH HHS
• UL1 TR000424 NCATS NIH HHS
• UL1 TR000067 NCATS NIH HHS
• UL1 TR001425 NCATS NIH HHS
• I01 BX001834 BLRD VA
• UL1 TR001082 NCATS NIH HHS
• UL1 RR029887 NCRR NIH HHS
• P01 AR049084 NIAMS NIH HHS
• P30 AR047363 NIAMS NIH HHS
• K23 AI099083 NIAID NIH HHS

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Affiliation(s)

Leah C. Kottyan Center for Autoimmune Genomics and Etiology, Division of Rheumatology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA United States Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Benjamin P. Davis Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Joseph D. Sherrill Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Kan Liu Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Mark Rochman Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Kenneth Kaufman Center for Autoimmune Genomics and Etiology, Division of Rheumatology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA United States Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA
Matthew T. Weirauch Center for Autoimmune Genomics and Etiology, Division of Rheumatology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Samuel Vaughn Center for Autoimmune Genomics and Etiology, Division of Rheumatology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Sara Lazaro Center for Autoimmune Genomics and Etiology, Division of Rheumatology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA United States Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA
Andrew M. Rupert Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Mojtaba Kohram Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Emily M. Stucke Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Katherine A. Kemme Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Albert Magnusen Center for Autoimmune Genomics and Etiology, Division of Rheumatology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA United States Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA
Hua He Division of Human Genetics, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Phillip Dexheimer Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Mirna Chehade Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York, USA
Robert A. Wood Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
Robbie D. Pesek Department of Pediatrics, University of Arkansas for Medical Sciences and Arkansas Children’s Hospital, Little Rock, Arkansas, USA
Brian P. Vickery Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA
David M. Fleischer Department of Pediatrics, National Jewish Health, Denver, Colorado, USA
Robert Lindbad The EMMES Corporation, Rockville, Maryland, USA
Hugh A. Sampson Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York, USA
Vince Mukkada Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Phil E. Putnam Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
J. Pablo Abonia Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
Lisa J. Martin Division of Human Genetics, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
John B. Harley Center for Autoimmune Genomics and Etiology, Division of Rheumatology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA United States Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA
Marc E. Rothenberg Division of Allergy and Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA

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Update on basic and clinical aspects of eosinophilic oesophagitis

The identification of a distinct syndrome, designated eosinophilic oesophagitis (EoE), with its own clinical and histopathological characteristics, was first described in the early 1990s. Meanwhile intense research has uncovered many molecular, immunological and clinical aspects of this chronic-inflammatory disorder. This article focuses exclusively on basic and clinical insights of EoE gathered during the last few years. Regarding aetiopathogenesis it has become clear that EoE is a food-triggered disease with milk and wheat as the dominant culprit food categories. However, it is still debated whether a disturbed mucosal integrity allowing allergens to cross the mucosal barrier, or changes in wheat and milk manufacturing might induce these inflammatory responses. Furthermore, basic science and clinical studies have accordingly confirmed that a chronic eosinophilic inflammation leads to a remodelling of the oesophagus with micro- and macro-morphological alterations, ending in a strictured oesophagus with impaired function. Fortunately, long-term therapeutic trials, using either topical corticosteroids or dietary allergen avoidance, have demonstrated that this sequela can be prevented or even reversed. This finding is of clinical relevance as it supports the initiation of a consistent anti-inflammatory therapy. Nevertheless, EoE is still an enigmatic disease and the long list of unanswered questions will certainly stimulate further research.

Efficacy, dose reduction, and resistance to high-dose fluticasone in patients with eosinophilic esophagitis

BACKGROUND & AIMS

We evaluated the efficacy and safety of high-dose swallowed fluticasone propionate (FP) and dose reduction in patients with eosinophilic esophagitis (EoE) and analyzed esophageal transcriptomes to identify mechanisms.

METHODS

We conducted a randomized, multisite, double-blind, placebo-controlled trial of daily 1760 mcg FP in participants age 3-30 years with active EoE. Twenty-eight participants received FP, and 14 participants received placebo. After 3 months, participants given FP who were in complete remission (CR) received 880 mcg FP daily, and participants in the FP or placebo groups who were not in CR continued or started, respectively, 1760 mcg FP daily for 3 additional months. The primary end point was histologic evidence for CR. Secondary end points were partial remission (PR), symptoms, compliance, esophageal gene expression, esophageal eosinophil count, and the relationship between clinical features and FP responsiveness.

RESULTS

After 3 months, 65% of subjects given FP and no subjects given placebo were in CR (P = .0001); 12% of those given FP and 8% of those given placebo were in PR. In the FP group, 73% of subjects remained in CR, and 20% were in PR after the daily dose was reduced by 50%. Extending FP therapy in FP-resistant participants did not induce remission. FP decreased heartburn severity (P = .041). Compliance, age, sex, atopic status, or anthropomorphic features were not associated with response to FP. Gene expression patterns in esophageal tissues of FP responders were similar to those of patients without EoE; there was evidence for heterogeneous steroid signaling in subjects who did not respond to FP and preliminary evidence for transcripts predictive of FP responsiveness.

CONCLUSIONS

Daily administration of a high dose of FP induces histologic remission in 65%-77% of patients with EoE after 3 months. A 50% dose reduction remained effective in 73%-93% of patients who initially responded to FP. Nonresponders had evidence of steroid resistance; histologic and molecular markers may predict resistance. Clinicaltrials.gov number: NCT00426283.

Eosinophilic esophagitis: overview of clinical management

A validated disease-specific symptom-assessment tool for eosinophilic esophagitis (EoE) has yet to be approved by regulatory authorities for use in clinical trials. Relevant end points for daily practice include EoE-related symptoms and esophageal eosinophilic inflammation. Endoscopic features should also be taken into account when establishing a therapy plan. A reasonable clinical goal is to achieve a reduction in EoE-related symptoms and esophageal eosinophilic inflammation. Evidence is increasing to support an anti-inflammatory maintenance therapy, as this can reduce esophageal remodeling. In EoE patients in clinical remission, annual disease monitoring with symptom, endoscopic, and histologic assessments of sustained treatment response is recommended.

Eosinophilic esophagitis: historical perspective on an evolving disease

Initial case series describing children and adults with symptoms related to esophageal dysfunction and dense esophageal eosinophilia lead to recognition of a "new" disease, eosinophilic esophagitis (EoE). Clinical, basic, and translational studies have provided a deeper understanding of this somewhat enigmatic disease that mechanistically is defined as an antigen-driven condition limited to the esophagus. This article summarizes many of the key historical features of EoE and provides a glimpse of potential future developments.

Clinical implications and pathogenesis of esophageal remodeling in eosinophilic esophagitis

In eosinophilic esophagitis (EoE), remodeling changes are manifest histologically in the epithelium and subepithelium where lamina propria fibrosis, expansion of the muscularis propria, and increased vascularity occur. The clinical symptoms and complications of EoE are largely consequences of esophageal remodeling. Available therapies have demonstrated variable ability to reverse existing remodeling changes of the esophagus. Systemic therapies have the potential of addressing subepithelial remodeling. Esophageal dilation remains a useful, adjunctive therapeutic maneuver in symptomatic adults with esophageal stricture. As novel treatments emerge, it is essential that therapeutic end points account for the fundamental contributions of esophageal remodeling to overall disease activity.

Activity assessment of eosinophilic esophagitis

The activity of eosinophilic esophagitis (EoE) can be assessed with patient-reported outcomes and biologic measures. Patient-reported outcomes include symptoms and quality of life, whereas biologic measures refer to endoscopic, histologic, and biochemical activity (e.g. blood biomarkers). So far, a validated tool to assess EoE activity in the above-mentioned dimensions is lacking. Given the lack of a standardized way to assess EoE activity in the various dimensions, the results of different clinical trials may be difficult to compare. For symptom assessment in adult patients, the symptom 'dysphagia' should be evaluated according to different standardized food consistencies. Furthermore, symptom assessment should take into account the following items: avoidance of specific food categories, food modification, and time to eat a regular meal. A distinct symptom recall period (e.g. 2 weeks) has to be defined for symptom assessment. Performing an 'esophageal stress test' with ingestion of a standardized meal to measure symptom severity bears the potential risk of acute food bolus impaction and should therefore be avoided. The description of endoscopic findings in EoE has meanwhile been standardized. Histologic evaluation of EoE activity should report either the size of the high-power field used or count the eosinophils per mm(2). There is a current lack of blood biomarkers demonstrating a good correlation with histologic activity in esophageal biopsies. The development and validation of an adult and pediatric EoE activity index is urgently needed not only for clinical trials and observational studies, but also for daily practice.

Eosinophilic esophagitis: an immune-mediated esophageal disease

Eosinophilic esophagitis (EoE) is an emerging disease defined by esophageal dysfunction, by typical endoscopic findings and by abnormal eosinophilic inflammation within the esophagus. Eosinophilic accumulation in the esophagus occurs as a result of esophageal overexpression of pro-inflammatory mediators, including T cells and mast cells, cytokines such as interleukin (IL)-13, IL-5 and IL-15, as well as chemoattractants (eotaxin and transforming growth factor-β1, fibroblast growth factor and the newly characterized gene--thymic stromal lymphopoietin, which is a key regulator of allergic sensitization initiation). The role of allergy, particularly food allergy in EoE is indisputable, as elimination diet is a proven commonly used treatment for the disease. However, unlike classical immediate IgE-mediated reaction to allergen, EoE is associated with an altered immune response, characterized by a combination of IgE-mediated and non-IgE-mediated mechanisms. In this review, we aim to discuss the many typical aspects of EoE as opposed to other entities involving the esophagus, with focusing on the aberrant immune-mediated key players contributing to the pathogenesis of this unique disease.

Unmet therapeutic needs in eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a clinicopathologic disease of increasing prevalence in children and adults worldwide. EoE is defined by a robust, acid-resistant, often panesophageal eosinophilia. Disease complications include food impactions and strictures. While much has been learned since it was first described in the late 1970s, there are still a number of unmet clinical needs. This review provides an overview of these and addresses our current state of progress in meeting these challenges. The best diagnostic criteria, the least invasive mechanisms for procuring tissue, the best therapeutic intervention, and an understanding of how therapies affect EoE natural history remain to be systematically addressed. In addition, the classification of EoE subjects by phenotype, genotype, and/or endotype is required but dependent upon further large-scale systematic studies.

Non- and semi-invasive methods of monitoring eosinophilic esophagitis

BACKGROUND/AIMS

Monitoring inflammation associated with eosinophilic esophagitis (EoE) relies on the identification of biomarkers that provide an objective measure of disease activity. To date, this metric has been the number of eosinophils in the squamous epithelial tissue. The search for alternative biomarkers as well as alternative methods to capture them has been the topic of much research.

METHODS

Based on clinical experience and a review of the literature, the aim of this chapter is to identify potential EoE biomarkers and methods to assess them.

RESULTS

With respect to the biomarkers, a number of candidates have arisen, including peripheral blood eosinophils, eosinophil granule proteins, Th2-related cytokines and exhaled nitric oxide. Methods to assess these biomarkers have included peripheral blood, luminal lavages and breath collections.

CONCLUSIONS

Future research will identify the best clinical outcome measure for EoE. While mucosal eosinophilia currently serves as a well-defined metric of inflammation, newer research studies will continue to address whether this number correlates reliably with other patient-reported outcomes, endoscopic findings, molecular analyses or other yet to be defined biomarkers.

Management guidelines of eosinophilic esophagitis in childhood

OBJECTIVES

Eosinophilic esophagitis (EoE) represents a chronic, immune/antigen-mediated esophageal disease characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation. With few exceptions, 15 eosinophils per high-power field (peak value) in ≥1 biopsy specimens are considered a minimum threshold for a diagnosis of EoE. The disease is restricted to the esophagus, and other causes of esophageal eosinophilia should be excluded, specifically proton pump inhibitor-responsive esophageal eosinophilia. This position paper aims at providing practical guidelines for the management of children and adolescents with EoE.

METHODS

Relevant literature from searches of PubMed, CINAHL, and recent guidelines was reviewed. In the absence of an evidence base, recommendations reflect the expert opinion of the authors. Final consensus was obtained during 3 face-to-face meetings of the Gastroenterology Committee and 1 teleconference.

RESULTS

The cornerstone of treatment is an elimination diet (targeted or empiric elimination diet, amino acid-based formula) and/or swallowed, topical corticosteroids. Systemic corticosteroids are reserved for severe symptoms requiring rapid relief or where other treatments have failed. Esophageal dilatation is an option in children with EoE who have esophageal stenosis unresponsive to drug therapy. Maintenance treatment may be required in case of frequent relapse, although an optimal regimen still needs to be determined.

CONCLUSIONS

EoE is a chronic, relapsing inflammatory disease with largely unquantified long-term consequences. Investigations and treatment are tailored to the individual and must not create more morbidity for the patient and family than the disease itself. Better maintenance treatment as well as biomarkers for assessing treatment response and predicting long-term complications is urgently needed.

Development and field testing of a novel patient-reported outcome measure of dysphagia in patients with eosinophilic esophagitis

BACKGROUND

Dysphagia is the hallmark of eosinophilic esophagitis (EoE), but no validated dysphagia instruments in this population exist.

AIM

To develop and field test a patient-reported outcome (PRO) for dysphagia in subjects with EoE.

METHODS

This was a multi-centre/multi-phase prospective study. The first phase developed a dysphagia questionnaire using qualitative methods. The second phase was a 30-day field trial to test the instrument and assess content validity. Adolescents and adults with EoE, active symptoms of dysphagia and oesophageal eosinophilia (≥15 eosinophils per high-power field) were enrolled. Solid-food-avoidance days, dysphagia days and actions taken to get relief were recorded. A dysphagia score was calculated and compared to the Straumann Dysphagia Instrument (SDI).

RESULTS

Ten adolescents and 10 adults were included in the first phase and the Dysphagia Symptom Questionnaire (DSQ), a three-item daily electronic diary, was developed. In the second phase, 35 subjects finished the field trial (18 adults, 17 adolescents, mean age 24, 54% male, 95% white, 54% currently on topical corticosteroids). The median number of dysphagia days per week was 2 for adolescents vs. 4 for adults (P < 0.001), and 2 for those on topical steroids vs. 4 for those not on topical steroids (P < 0.001). The DSQ score strongly correlated with the number of dysphagia days (R = 0.96; P < 0.001) and the SDI (R = 0.77; P < 0.001).

CONCLUSIONS

The DSQ, a three-question patient-reported outcome, was successfully developed and field tested. The DSQ had content validity and the score accurately measured dysphagia frequency and intensity. The Dysphagia Symptom Questionnaire is suitable for use in clinical trials of EoE patients with dysphagia.