The impact of dietary therapy on clinical and biologic parameters of pediatric patients with eosinophilic esophagitis

Breakthroughs in understanding and treating eosinophilic gastrointestinal diseases presented at the CEGIR/TIGERs Symposium at the 2022 American Academy of Allergy, Asthma & Immunology Meeting

The Consortium of Eosinophilic Gastrointestinal Diseases and The International Gastrointestinal Eosinophil Researchers organized a day-long symposium at the 2022 Annual Meeting of the American Academy of Allergy, Asthma & Immunology. The symposium featured a review of recent discoveries in the basic biology and pathogenesis of eosinophilic gastrointestinal diseases (EGIDs) in addition to advances in our understanding of the clinical features of EGIDs. Diagnostic and management approaches were reviewed and debated, and clinical trials of emerging therapies were highlighted. Herein, we briefly summarize the breakthrough discoveries in EGIDs.

A Practical Update on Pediatric Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is an emerging atopic disease of unknown etiology limited to the esophagus. The pathogenesis is still understood and is likely characterized by type 2 inflammation. Food allergens are the primary triggers of EoE that stimulate inflammatory cells through an impaired esophageal barrier. In children and adolescents, clinical presentation varies with age and mainly includes food refusal, recurrent vomiting, failure to thrive, abdominal/epigastric pain, dysphagia, and food impaction. Upper-gastrointestinal endoscopy is the gold standard for diagnosing and monitoring EoE. EoE therapy aims to achieve clinical, endoscopic, and histological ("deep") remission; prevent esophageal fibrosis; and improve quality of life. In pediatrics, the cornerstones of therapy are proton pump inhibitors, topical steroids (swallowed fluticasone and viscous budesonide), and food elimination diets. In recent years, much progress has been made in understanding EoE pathogenesis, characterizing the clinical and molecular heterogeneity, and identifying new therapeutic approaches. Notably, clinical, molecular, endoscopic, and histological features reflect and influence the evolution of inflammation over time and the response to currently available treatments. Therefore, different EoE phenotypes and endotypes have recently been recognized. Dupilumab recently was approved by FDA and EMA as the first biological therapy for adolescents (≥12 years) and adults with active EoE, but other biologics are still under consideration. Due to its chronic course, EoE management requires long-term therapy, a multidisciplinary approach, and regular follow-ups.

Nutritional risks in children with food allergy

BACKGROUND

Food allergies (FA) are a growing problem in the pediatric population and clinical features differ according to the underlying immunological mechanisms. While the primary management strategy is to eliminate the culprit food from the diet, assessment of the potential nutritional risks of elimination is also an integral part of management. In cases that do not improve over time; if you have basic food allergies and multiple food allergies, this can also lead to negative nutritional consequences. The contribution of basic nutrients, economical and easily accessible foods to the diet, is critical and has an important place in meeting the daily adequate intake of many nutrients. In the presence of food allergy, it is necessary to meet the vitamins and minerals that cannot be obtained from allergic foods, with alternative sources or supplements. For example, insufficient calcium intake in cow's milk allergy (CMA), the most common FA in early childhood, is very likely if an alternative supplement has not been introduced. In the management of CMA, choosing the appropriate formula and/or supplement for the clinical characteristics of children, when necessary, has an important place. In conclusion, nutritional risk assessment of children with FA requires a comprehensive, detailed, and multidisciplinary approach.

Efficacy of Elimination Diets in Eosinophilic Esophagitis: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Eosinophilic esophagitis (EoE) can be treated by proton pump inhibitors, topical corticosteroids, or dietary measures. This study systematically assessed the efficacy of 4 major dietary treatment regimens in EoE, updating the evidence presented in a meta-analysis from 2014.

METHODS

Electronic databases such as PubMed, Scopus, and Web of Science, and other sources were searched up to September 2022 to identify studies on dietary treatment of EoE. Based on histologic remission criteria, the efficacy of these treatments was pooled and analyzed with respect to the type of dietary regimen: 6-food elimination diet (SFED), 4-food elimination diet (FFED), 1-food elimination diet (OFED), and a targeted elimination diet (TED). Clinical response rates, food sensitization, and efficacies for a pediatric subpopulation were calculated. Influencing variables on efficacies were estimated via meta-regression analyses.

RESULTS

Thirty-four studies with 1762 patients met the inclusion criteria. The overall rate of histologic remission was 53.8% (95% CI, 48.0%-59.6%), and in the individual dietary groups was 61.3% (95% CI, 53.0%-69.3%) for SFED, 49.4% (95% CI, 32.5%-66.3%) for FFED, 51.4% (95% CI, 42.6%-60.1%) for OFED, and 45.7% (95% CI, 32.0%-59.7%) for TED. Dietary regimen and patient age did not significantly affect rates of histologic remission. The overall rate of clinical response was 80.8% (95% CI, 72.3%-88.2%), with response rates of 92.8% (95% CI, 81.2%-99.6%) for SFED, 74.1% (95% CI, 49.8%-92.6%) for FFED, 87.1% (95% CI, 58.4%-99.9%) for OFED, and 69.0% (95% CI, 50.2%85.3%) for TED.

CONCLUSIONS

Dietary therapy is an effective treatment for EoE patients of any age. The current results could support a trend toward less-restrictive dietary regimens as a primary treatment option.

Tolerability and safety of a new elimination diet for pediatric eosinophilic gastritis and duodenitis

BACKGROUND

Non-esophageal eosinophilic gastrointestinal disorders (non-EoE EGIDs) are chronic inflammatory disorders with massive infiltration of eosinophils into the gastrointestinal tract. Food elimination diets are potentially effective treatments. But the existing dietary therapies have various weak points. We developed a new regimen to compensate for the shortcomings of the elemental diet and 6-food elimination diet. The new regimen consists of an amino-acid-based formula, potatoes, vegetables, fruits and restricted seasonings. We named it the "Rainbow Elimination Diet (ED)." The aims of this study were to evaluate the tolerability and safety of this diet.

METHODS

A retrospective medical record examination was conducted at the National Center for Child Health and Development covering the period from January 2010 through December 2018. The medical records of patients (age 2-17 y) with histologically diagnosed non-EoE EGIDs were reviewed. The tolerability, nutritional intake, symptoms, and blood test findings were evaluated.

RESULTS

Nineteen patients were offered several kinds of food-elimination diets. Seven patients (eosinophilic gastritis: 5; gastroenteritis: 1; duodenitis: 1) were treated with Rainbow ED. Six patients were compliant with this diet. The median duration of the diet induction phase was 15 days (range 14-30). All 5 patients who had had symptoms just before the induction phase became symptom-free. The body weight decreased in 5 patients (median -0.6 kg), probably because the serum protein increased, resulting in reduced edema. All 5 patients with hypoproteinemia had elevated serum albumin (median 2.9-3.5 g/dL). The ingested nutritional elements were calculated, and most of them were sufficient, except for fat and selenium.

CONCLUSIONS

The Rainbow ED was well-tolerated and safe for pediatric non-EoE EGIDs.

Nutritional and Psychological Considerations for Dietary Therapy in Eosinophilic Esophagitis

The step-up empiric elimination diet, starting from one/two food groups of most local allergens remains the current gold standard for a dietary approach in eosinophilic esophagitis (EoE) patients. Milk, followed by wheat and egg, is the most frequent food that triggers EoE in pediatric and adult patients. Elimination diets, with restrictions over four food groups, may be limited to highly motivated patients, in which nutritional counseling is recommended. Malnourishment is uncommon in EoE patients and likely multifactorial (concomitant gastrointestinal eosinophilic disorders or IgE-mediated food allergies, feeding difficulties, abnormal feeding behavior). Avoidant/restrictive food intake disorder in EoE children on highly restrictive diets was lately described and may warrant specific psychological support. As for adults, quality of life may be impaired by symptom severity and dietary restrictions, aside from recently reported food impaction-related specific anxiety in up to 43% of patients. Severe symptoms, feeding dysfunction, and diet restrictions may negatively influence psychosocial adjustment for patients and their caregivers.

Dietary Management of Eosinophilic Esophagitis: Tailoring the Approach

Eosinophilic esophagitis (EoE) is a unique form of non-immunoglobulin E-mediated food allergy, restricted to the esophagus, characterized by esophageal eosinophil-predominant inflammation and dysfunction. The diagnosis requires an esophago-gastroduodenoscopy with esophageal biopsies demonstrating active eosinophilic inflammation with 15 or more eosinophils/high-power field, following the exclusion of alternative causes of eosinophilia. Food allergens trigger the disease, withdairy/milk, wheat/gluten, egg, soy/legumes, and seafood the most common. Therapeutic strategies comprise dietary restrictions, proton pump inhibitors, topical corticosteroids, biologic agents, and esophageal dilation when strictures are present. However, avoidance of trigger foods remains the only option targeting the cause, and not the effect, of the disease. Because EoE relapses when treatment is withdrawn, dietary therapy offers a long-term, drug-free alternative to patients who wish to remain off drugs and still be in remission. There are currently multiple dietary management strategies to choose from, each having its specific efficacy, advantages, and disadvantages that both clinicians and patients should acknowledge. In addition, dietary regimens should be tailored around each individual patient to increase the chance of tolerability and long-term adherence. In general, liquid elemental diets devoid of antigens and elimination diets restricting causative foods are valuable options. Designing diets on the basis of food allergy skin tests results is not reliable and should be avoided. This review summarizes the most recent knowledge regarding the clinical use of dietary measures in EoE. We discussed endpoints, rationale, advantages and disadvantages, and tailoring of diets, as well as currently available dietary regimens for EoE.

Eosinophilic esophagitis: clinical, endoscopic, histologic and therapeutic differences and similarities between children and adults

In the absence of secondary causes, eosinophilic esophagitis (EoE) is a chronic, local, progressive, T-helper type 2 immune-mediated disorder characterized by symptoms of esophageal dysfunction and eosinophil-predominant inflammation. In the last 20 years, the incidence and prevalence of EoE have risen sharply, and the chances of encountering affected patients in clinics and endoscopy rooms have increased. Nevertheless, it is estimated that the mean diagnostic delay of EoE is 4-6 years in both children and adults. Unfortunately, the longer the disease stays unrecognized, the likelier it is for the patient to have persistent or increased esophageal eosinophilic inflammation, to complain of non-resolving symptoms, and to develop fibrotic complications. Early detection depends on the recognition of initial clinical manifestations that vary from childhood to adulthood and even among patients of the same age. The disease phenotype also influences therapeutic approaches that include drugs, dietary interventions, and esophageal dilation. We have herein reviewed epidemiologic, clinical, endoscopic, and histologic features and therapeutic options of EoE focusing on differences and similarities between children and adults that may certainly serve in daily clinical practice.

Diet Therapy in Eosinophilic Esophagitis. Focus on a Personalized Approach

Eosinophilic esophagitis (EoE) is a chronic allergic disease defined by a marked eosinophilic inflammation and symptoms of esophageal dysfunction. EoE is a heterogeneous disease and severely impacts the quality of life of affected patients. The current therapeutic management of EoE is based on two cornerstones: medication and diet therapy, both effective but limited by several critical issues. The choice of one or the other therapy might depend on the different disease phenotypes (allergic vs. non-allergic, inflammatory vs. fibro-stenotic), patient's age (adult vs. childhood-onset), food habits, patient/family preference, and familiar financial resource. Diet therapy is a successful treatment but limited by low patient adherence, the need for several endoscopies, food restrictions, psychosocial impact, and potential nutritional deficiencies. All these limitations could be effectively overcome with multidisciplinary and personalized management. This review summarizes the most recent evidence on the dietary elimination approaches and will provide a practical guide to clinicians in managing and implementing dietary therapy for patients with EoE.

Malnutrition in Eosinophilic Gastrointestinal Disorders

Primary eosinophilic gastrointestinal disorders (EGIDs) are emerging chronic/remittent inflammatory diseases of unknown etiology, which may involve any part of the gastrointestinal (GI) tract, in the absence of secondary causes of GI eosinophilia. Eosinophilic esophagitis is the prototype of eosinophilic gastrointestinal disorders and is clinically characterized by symptoms related to esophageal inflammation and dysfunction. A few studies have assessed the nutritional status of patients with eosinophilic gastrointestinal disorders, showing conflicting results. This review summarizes the current evidence on the nutritional status of patients with EGIDs, focusing on the pediatric point of view and also speculating potential etiological mechanisms.

Nutritional approach to eosinophilic esophagitis: which diet and when

Dietary elimination therapy has been for a long time an option for patients with eosinophilic esophagitis (EoE) and remains the only therapy targeting the cause of the disease. Different dietary approaches have been described along the last 3 decades, and cumulative evidence has defined the effectiveness and usefulness of each approach. Elemental diets are highly effective to induce EoE remission, but unpractical in most patients. Allergy testing-directed food restrictions resulted inefficient to induce remission in a significant proportion of patients (especially adults) and show a low concordance with the dietary causes of EoE. Empiric elimination diets are currently considered the most effective drug-free treatment for patients of all ages with EoE, after widely providing reproducible results. Highly restrictive empiric six-food elimination diets have paved the way to most efficient and less restrictive step-up approaches, which now include four-food and two-food elimination diets. The potential role of milk-elimination, especially in children, should be also considered. Multiple factors including demographics, nutritional status, patient and family lifestyles, social and financial support, and acceptance of repeated endoscopies influence the results of dietary therapy. Dietary therapy in EoE should be patient centered, and the patients and/or their families together with the medical provider should participate in the decision to set up this treatment. This article updates recent knowledge on dietary therapy for EoE and provides guideline to choose the most suitable alternative for patients with EoE, as well as practical tips to achieve the best results in clinical practice.

Dietary therapy for eosinophilic esophagitis: chances and limitations in the clinical practice

INTRODUCTION

Eosinophilic esophagitis (EoE) is a non-Immunoglobulin E-mediated food allergy that currently represents the main cause of dysphagia and food impaction in children and young adults. Diet remains the only therapy targeting the cause of the disease. Relevant advances in recent years allow novel approaches to dietary therapy in EoE.

AREAS COVERED

An up-to-date review on dietary therapy for EoE is provided, as a potential first-line anti-inflammatory therapy able to induce and maintain remission in a significant proportion of patients. Unpractical elemental diets and suboptimal food allergy testing-directed food restrictions paved the way for empiric elimination diets, which currently are to be considered as the most effective drug-free treatment for EoE. After largely restrictive empiric six-food elimination diets, most efficient step-up approaches now include four-food and two-food elimination diets. The potential of milk-elimination is also discussed.

EXPERT COMMENTARY

An empiric elimination diet step-up strategy should be currently considered as the initial approach for dietary treatment in EoE patients of all ages. Compared to a top-down strategy, step-up diets reduce the need for endoscopic procedures, shorten diagnostic process times, and avoid unnecessary restrictions. Furthermore, early identification of responders with few food triggers may select best candidates for maintenance dietary 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.

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.

Strategy for Food Reintroduction Following Empiric Elimination and Elemental Dietary Therapy in the Treatment of Eosinophilic Gastrointestinal Disorders

PURPOSE OF REVIEW

This review presents the available data regarding efficacy of nutritional therapy, highlighting clinical decision points and a strategy for reintroduction of foods following an elemental diet for treatment of eosinophilic gastrointestinal disorders.

RECENT FINDINGS

Elemental and empiric elimination diets are highly effective treatments for eosinophilic gastrointestinal diseases. Standardization in the reintroduction phase, after utilizing the diet for disease remission, is lacking. Clinicians are confronted with multiple challenges regarding the best practice for food reintroduction and identification of potential dietary triggers including order of foods being challenged and duration between endoscopic procedures. Individualization is required for preference and adherence to optimize quality of life and treatment success for this burdensome and life altering immune driven gastrointestinal disorder. Age specific concerns for children, teenagers, and adults should be assessed using a patient centric approach.

The use of amino acid-based nutritional feeds is effective in the dietary management of pediatric eosinophilic oesophagitis

INTRODUCTION

Eosinophilic oesophagitis (EoE) is an immune-mediated, chronic disease characterized by eosinophilic inflammation and esophageal dysfunction. Specific food allergens including cow's milk protein, are partially causative to disease progression, and dietary management forms three main options; the elemental diet (ED), the empirical elimination diet (EED), and the targeted elimination diet (TED). The dietary choice should be individualized, however, the European Society for Pediatric Gastroenterology, Hepatology and Nutrition guidelines recommend an ED for pediatric EoE with multiple food allergies, failure to thrive, unresponsive disease or unable to follow a highly restricted diet. The aim of this narrative review was to explore the effectiveness of the ED (using amino acid formula [AAF]), in the management of pediatric EoE.

METHODS

Literature searches were performed to identify eligible studies that described outcomes including eosinophil count, clinical symptoms, growth, and medications.

RESULTS

Overall, 10 eligible studies were found, with n = 462 patients assigned to receive AAF from a total of n = 748 (average age 6.7 years), for a duration of 4 to 8 weeks. The use of AAF reduced eosinophil levels and demonstrated remission (defined as ≤10 eosinophils per high power field) in 75%-100% of children with improvements, if not resolution, in clinical symptoms. AAF was more clinically effective than the use of the EED or TED, where remission rates were 75%-81% and 40%-69%, respectively. Few studies collected growth outcomes, however where documented these were positive for those on AAF. The long-term impacts of each diet were not thoroughly explored.

CONCLUSIONS

The use of AAF is a clinically effective management option for pediatric EoE, and further research is required to guide long-term management.

Illuminating Elimination Diets: Controversies Regarding Dietary Treatment of Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is an immune-mediated disease triggered by food antigens for which dietary elimination treatment can induce and sustain histologic remission. Our review aims to describe the state of the art regarding dietary treatment of EoE, highlighting a number of areas of controversy related to dietary therapy in EoE, including novel modalities for determining food triggers, making the empiric dietary elimination process more efficient, issues of cross-contamination and "dosing" of how much food to avoid or add back, costs and effects on quality of life, long-term efficacy, and the risk of developing immediate IgE-type reactions after initial dietary elimination. Elemental formulas, empiric elimination diets, and targeted allergy test-directed elimination diets are well-described treatments for EoE. Although elemental diets are most efficacious, their clinical use is limited by cost and the palatability of an exclusively liquid diet. While empiric elimination is less effective than elemental formula-based diets, they are more easily implemented and often sustainable. Since the comparative effectiveness of elimination diets with proton-pump inhibitors and swallowed topical steroids remains unknown, there are multiple areas to address with future research.

Nutritional disorders resulting from food allergy in children

The elimination of food allergens that contribute essential nutrients in paediatrics may lead to the development of nutritional disorders. The most common nutritional disorders include poor growth, micronutrient deficiencies and feeding difficulties. Of the aforementioned, growth faltering has been well studied and is seen as a common presenting factor in paediatric food allergy. However, the use of different criteria and cut-off values makes it difficult to establish the overall effect. The impact of number and type of foods eliminated and comorbidities has yielded varying results, although there seems to be a trend towards worsening growth with atopic dermatitis and the avoidance of cow's milk. Low micronutrient intake is common in paediatric food allergy; however, a low intake does not necessarily translate into a deficiency as measured by biomarkers. Vitamin D and calcium have been well studied, and a long-lasting impact on bone mineral density has been found. However, other micronutrient deficiencies have also been found and should also be considered. Feeding difficulties is a common complaint in clinical practice, but limited data have been published in food allergy. Poor growth and reflux/vomiting have been shown to be associated with feeding difficulties, in particular in non-IgE-mediated food allergies. There seems to be a long-lasting effect on feeding, in particular in cow's milk allergy, which needs to be taken into account with dietary input. The interplay between growth, feeding difficulties and micronutrient deficiencies has been implied in some studies, but cause and effect is not well established and requires further research.

Minimally invasive biomarker studies in eosinophilic esophagitis: A systematic review

BACKGROUND

Eosinophilic esophagitis (EoE) is a chronic, inflammatory disease of the esophagus that currently requires repeated endoscopic biopsies for diagnosis and monitoring because no reliable noninvasive markers have been identified.

OBJECTIVE

To identify promising minimally invasive EoE biomarkers and remaining gaps in biomarker validation.

METHODS

We performed a systematic review of EMBASE, Ovid MEDLINE, PubMed, and Web of Science from inception to June 6, 2017. Studies were included if patients met the 2007 consensus criteria for EoE diagnosis, a minimally invasive biomarker was assessed, and the study included at least 1 control for comparison.

RESULTS

The search identified 2094 studies, with 234 reviewed at full-text level, and 49 included in the analysis (20 adult, 19 pediatric, 7 pediatric and adult, and 3 not stated). Most (26 of 49) were published after 2014. Thirty-five studies included healthy controls, 9 analyzed atopic controls, and 29 compared samples from patients with active and inactive EoE. Minimally invasive biomarkers were obtained from peripheral blood (n = 41 studies), sponge or string samples (n = 3), oral or throat swab secretions (n = 2), breath condensate (n = 2), stool (n = 2), and urine (n = 2). The most commonly reported biomarkers were peripheral blood eosinophils (n = 16), blood and string eosinophil granule proteins (n = 14), and eosinophil surface or intracellular markers (n = 12). EoE biomarkers distinguished active EoE from healthy controls in 23 studies, atopic controls in 2 studies, and inactive EoE controls in 20 studies.

CONCLUSION

Several promising minimally invasive biomarkers for EoE have emerged; however, few are able to differentiate EoE from other atopic diseases.

Systematic review of histological remission criteria in eosinophilic esophagitis

Elemental diets, dietary elimination, and steroid therapies are the most common therapies in the clinical trials for eosinophilic esophagitis (EoE). Histological findings (usually reported as eosinophils per microscopic high‐powered field [hpf]) remain the most common end‐point used to define response. Yet, the threshold for defining “response” and “remission” are ill‐defined among consensus guidelines and may vary from study to study. We conducted a systematic literature review of articles on eosinophilic esophagitis, published between January 2007 and November 2017, considering histological remission as the primary outcome. We abstracted treatment information and definitions of histological remission or response. A comparison of definitions of histological remission across and within institutions was performed. A total of 61 articles were included in this review, with approximately 60% of the studies published from centers in the United States. Histological definitions of remission of EoE ranged from 0 to ≤20 eosinophils/hpf. The most stringent criteria, ranging from 0 to ≤5 eosinophils/hpf, were commonly used in interventional trial studies that examined the effects of new treatments. We found remarkable variability in definitions between studies, treatment types, and regions. Age or epidemiological distribution of study subjects did not influence the criteria for histological remission. Clinical and histological improvements are important measures of the effects of treatment. Histological findings, the most objective measure of treatment, should provide an optimal method for comparing the effectiveness of various treatments. Yet, our findings suggest a lack of consistent remission criteria in published studies. Considering these inconsistencies, it is difficult to compare the effectiveness of various treatments.

Six-Food Elimination Diet and Topical Steroids are Effective for Eosinophilic Esophagitis: A Meta-Regression

BACKGROUND

Topical corticosteroids or six-food elimination diet is recommended as initial therapy for eosinophilic esophagitis (EoE).

AIMS

We aimed to summarize published manuscripts that report outcomes of these therapies for EoE.

METHODS

We performed a systematic review in MEDLINE, Web of Science, and Embase of published manuscripts describing topical fluticasone, topical budesonide, and six-food elimination diet as therapies for EoE. We conducted meta-analysis of symptom improvement and the change in peak mucosal eosinophil count, with heterogeneity between studies examined with meta-regression analysis.

RESULTS

Systematic review yielded 51 articles that met inclusion criteria. Summary histologic response rates were 68.3% [95% prediction limits (PL) 16.2-96.0%] for fluticasone, 76.8% (95% PL 36.1-95.1%) for budesonide, and 69.0% (95% PL 31.9-91.4%) for six-food elimination diet. Corresponding decreases in eosinophil counts were 37.8 (95% PL 19.0-56.7), 62.5 (95% PL 125.6 to -0.67, and 44.6 (95% PL 26.5-62.7), respectively. Symptom response rates were 82.3% (95% PL 68.1-91.1%), 87.9% (95% PL 42.7-98.6%), and 87.3% (95% PL 64.5-96.3%), respectively. Meta-regression analyses decreased the initially large estimate of residual heterogeneity and suggested differences in histologic response rate associated with study populations' baseline eosinophil count and age.

CONCLUSIONS

The literature describing topical corticosteroids and six-food elimination diet consists of small studies with diverse methods and population characteristics. Meta-analysis with meta-regression shows initial histologic and symptomatic response rates on the same order of magnitude for topical corticosteroids and six-food elimination diet, but heterogeneity of study designs prevents direct comparison of modalities.

Update on dietary therapy for eosinophilic esophagitis in children and adults

Eosinophilic esophagitis (EoE) is a chronic inflammatory esophageal disease triggered predominantly, but not excusively, by food antigens. Elimination diet thus remains the only therapy targeting the cause of the disease. Importantly, EoE is a unique form of non-IgE mediated food allergy, largely dependant upon delayed, cell-mediated hypersensitivity. Areas covered: A comprehensive review of literature to summarize and update the most relevant advances on dietary therapy for pediatric and adult EoE patients is conducted. Expert commentary: None of the currently available food allergy tests adequately predict food triggers for EoE, especially in adults. Elemental diet (exclusive feeding with aminoacid-based formulas) and empiric six-food elimination diet, withdrawing cow´s milk, wheat, egg, soy, nuts and fish/seafood for 6 weeks, have consistently shown the best cure rates. However, their high level of restriction and need for multiple endoscopies (top-down approach) have been a deterrent for patients and physicians. Less restrictive empiric schemes, like a four-food (animal milk, gluten-containing cereals, egg, legumes) or a two-food (animal milk and gluten-containing cereals) elimination diet have lately shown encouraging results. Therefore, a novel step-up strategy (2-4-6) may enhance patient uptake and promptly identify most responders to empiric diets with few food triggers, besides saving unnecessary dietary restrictions and endoscopic procedures.

Safety of a New Amino Acid Formula in Infants Allergic to Cow's Milk and Intolerant to Hydrolysates

OBJECTIVES

Amino acid-based formulas (AAFs) are recommended for children with cow's-milk allergy (CMA) failing to respond to extensively hydrolysed formulas (eHFs). We evaluated the effects of a new thickened AAF (TAAF, Novalac), containing a pectin-based thickener, and a reference AAF (RAAF, Neocate) on allergy symptoms and safety, through blood biochemistry analysis and growth.

METHODS

Infants (ages < 18 months) with CMA symptoms failing to respond to eHFs were randomised in a double-blind manner to receive TAAF or RAAF for 3 months. All of the infants were then fed TAAF for 3 additional months. Paediatric visits occurred at 1, 3, and 6 months. Blood samples were collected at inclusion and 3 months.

RESULTS

Results at 1 month were previously described. The 75 infants with proven CMA and eHF intolerance tolerated their allocated formula. At 3 months, the dominant allergic symptom had disappeared in 76.2% of the infants with TAAF and in 51.5% of the infants with RAAF (P = 0.026). The Scoring Atopic Dermatitis Index significantly improved more with TAAF than with RAAF (-27.3 ± 2.3 vs -20.8 ± 2.2, P = 0.048). Of the infants, 92.9% had normal stools (soft or formed consistency) with TAAF vs 75.8% with RAAF (P = 0.051). More infants in TAAF group had better quality of nighttime sleep (P = 0.036) and low frequency of irritability signs (P < 0.001). With both formulas, all of the biochemical parameters were within normal ranges. There were no differences between the 2 groups in any of the anthropometric z scores.

CONCLUSIONS

The new TAAF was tolerated by all of the infants with CMA and intolerance to eHFs. Anthropometric and clinical data showed that both formulas were safe.

The Role of Environmental Exposures in the Etiology of Eosinophilic Esophagitis: A Systematic Review

Eosinophilic esophagitis (EoE) is an emerging clinicopathologic entity defined by abnormal esophageal eosinophilic infiltration. Management of this disease is hampered by limited understanding of etiologic and controllable risk factors. The aim of this systematic review was to determine the environmental risk factors for EoE. We searched the PubMed, Web of Science, and EMBASE databases from January 1, 1950, through June 30, 2015. To identify additional relevant studies, we hand searched bibliographies of included articles. We limited the review to articles using human subjects and consisting of case reports, case series, cross-sectional and cohort studies, and clinical trials. Nineteen articles discuss the risk of environmental exposures on EoE and indicate that environment plays a large role in the etiology of EoE. Seasonal, geographic, and climate-based differences in disease prevalence have been reported, but the exact mediators of this process, possibly aeroallergens that vary over time and from place to place, remain elusive.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2014

This review highlights some of the research advances in anaphylaxis; hypersensitivity reactions to foods, drugs, and insects; and allergic skin diseases that were reported in the Journal in 2014. Studies on food allergy suggest worrisomely high rates of peanut allergy and food-induced anaphylaxis-related hospitalizations. Evidence is mounting to support the theory that environmental exposure to peanut, such as in house dust, especially with an impaired skin barrier attributed to atopic dermatitis (AD) and loss of function mutations in the filaggrin gene, is a risk factor for sensitization and allergy. Diagnostic tests are improving, with early studies suggesting the possibility of developing novel cellular tests with increased diagnostic utility. Treatment trials continue to show the promise and limitations of oral immunotherapy, and mechanistic studies are elucidating pathways that might define the degree of efficacy of this treatment. Studies have also provided insights into the prevalence and characteristics of anaphylaxis and insect venom allergy, such as suggesting that baseline platelet-activating factor acetylhydrolase activity levels are related to the severity of reactions. Advances in drug allergy include identification of HLA associations for penicillin allergy and a microRNA biomarker/mechanism for toxic epidermal necrolysis. Research identifying critical events leading to skin barrier dysfunction and the polarized immune pathways that drive AD have led to new therapeutic approaches in the prevention and management of AD.