Sustained Remission of Eosinophilic Esophagitis Following Discontinuation of Dietary Elimination in Children

Persistent esophageal changes after histologic remission in eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is characterized by persistent or relapsing allergic inflammation, and both clinical and histologic features of esophageal inflammation persist over time in most individuals. Mechanisms contributing to EoE relapse are not understood, and chronic EoE-directed therapy is therefore required to prevent long-term sequelae.

OBJECTIVE

We investigated whether EoE patients in histologic remission have persistent dysregulation of esophageal gene expression.

METHODS

Esophageal biopsy samples from 51 pediatric and 52 adult subjects with EoE in histopathologic remission (<15 eosinophils per high-power field [eos/hpf]) and control (48 pediatric and 167 adult) subjects from multiple institutions were subjected to molecular profiling by the EoE diagnostic panel, which comprises a set of 94 esophageal transcripts differentially expressed in active EoE.

RESULTS

Defining remission as <15 eos/hpf, we identified 51 and 32 differentially expressed genes in pediatric and adult EoE patients compared to control individuals, respectively (false discovery rate < 0.05). Using the stringent definition of remission (0 eos/hpf), the adult and pediatric cohorts continued to have 18 and 25 differentially expressed genes (false discovery rate < 0.05). Among 6 shared genes between adults and children, CDH26 was upregulated in both children and adults; immunohistochemistry demonstrated increased cadherin 26 staining in the epithelium of EoE patients in remission compared to non-EoE controls. In the adult cohort, POSTN expression correlated with the endoscopic reference system score (Spearman r = 0.35, P = .011), specifically correlating with the rings' endoscopic reference system subscore (r = 0.53, P = .004).

CONCLUSION

We have identified persistent EoE-associated esophageal gene expression in patients with disease in deep remission. These data suggest potential inflammation-induced epigenetic mechanisms may influence gene expression during remission in EoE and provide insight into possible mechanisms that underlie relapse in EoE.

IgG4 autoantibodies and autoantigens in the context of IgG4-autoimmune disease and IgG4-related disease

Immunoglobulins are an essential part of the humoral immune response. IgG4 antibodies are the least prevalent subclass and have unique structural and functional properties. In this review, we discuss IgG4 class switch and B cell production. We review the importance of IgG4 antibodies in the context of allergic responses, helminth infections and malignancy. We discuss their anti-inflammatory and tolerogenic effects in allergen-specific immunotherapy, and ability to evade the immune system in parasitic infection and tumour cells. We then focus on the role of IgG4 autoantibodies and autoantigens in IgG4-autoimmune diseases and IgG4-related disease, highlighting important parallels and differences between them. In IgG4-autoimmune diseases, pathogenesis is based on a direct role of IgG4 antibodies binding to self-antigens and disturbing homeostasis. In IgG4-related disease, where affected organs are infiltrated with IgG4-expressing plasma cells, IgG4 antibodies may also directly target a number of self-antigens or be overexpressed as an epiphenomenon of the disease. These antigen-driven processes require critical T and B cell interaction. Lastly, we explore the current gaps in our knowledge and how these may be addressed.

Increasing Age at the Time of Diagnosis and Evolving Phenotypes of Eosinophilic Esophagitis Over 20 Years

BACKGROUND

The presentation of eosinophilic esophagitis (EoE) is heterogeneous, but trends over time are not known.

AIM

To determine whether clinical and endoscopic phenotypes at EoE diagnosis have changed over the past 2 decades.

METHODS

In this retrospective cohort study, adults and children with newly diagnosed EoE were phenotyped as follows: (1) inflammatory vs fibrostenotic vs mixed on endoscopy; (2) atopic vs non-atopic; (3) age at symptom onset; (4) age at diagnosis; (5) presence of autoimmune or connective tissue disease; and (6) responsive to steroids. The prevalence of different phenotypes was categorized by 5-year intervals. Multivariate analysis was performed to assess for changes in patient features over time.

RESULTS

Of 1187 EoE patients, age at diagnosis increased over time (from 22.0 years in 2002-2006 to 31.8 years in 2017-2021; p < 0.001) as did the frequency of dysphagia (67% to 92%; p < 0.001). Endoscopic phenotypes were increasingly mixed (26% vs 68%; p < 0.001) and an increasing proportion of patients had later onset of EoE. However, there were no significant trends for concomitant autoimmune/connective tissue disease or steroid responder phenotypes. On multivariate analysis, after accounting for age, dysphagia, and food impaction, the increase in the mixed endoscopic phenotype persisted (aOR 1.51 per each 5-year interval, 95% CI 1.31-1.73).

CONCLUSION

EoE phenotypes have changed over the past two decades, with increasing age at diagnosis and age at symptom onset. The mixed endoscopic phenotype also increased, even after controlling for age and symptomatology. Whether this reflects changes in provider recognition or disease pathophysiology is yet to be elucidated.

Long-Term Outcomes of the Six-Food Elimination Diet and Food Reintroduction in a Large Cohort of Adults With Eosinophilic Esophagitis

INTRODUCTION

Eosinophilic esophagitis (EoE) is an immune-mediated inflammatory condition with tissue eosinophilia resulting in esophageal dysfunction. The six-food elimination diet (SFED) is an EoE treatment approach that removes milk, wheat, soy, eggs, tree nuts/peanuts, and fish/shellfish. After histologic remission, food reintroduction occurs to identify a food trigger. Outcomes from large series of adults undergoing SFED and food reintroduction as clinical care are not known.

METHODS

A retrospective review (2006-2021) of adult patients with EoE from an academic center was completed. Patients were classified as full responders (<15 eos/hpf) after SFED. If reintroduction was pursued, food triggers identified were recorded.

RESULTS

Two hundred thirteen patients completed SFED. One hundred fifteen patients (54%) had response <15 eos/hpf after SFED. Seventy-seven percent of responders had symptom improvement. Thirty-two percent of initial nonresponders underwent repeat dietary elimination. Fifty-eight percent of patients (n = 123) achieved <15 eos/hpf after either initial or extended SFED. Seventy-eight percent of responders underwent food reintroduction. Sixty-nine percent had 1 food trigger identified, 24% had 2 allergens identified, and 4% had 3 allergens identified. The most common food triggers identified were milk, wheat, and soy.

DISCUSSION

This study describes the largest cohort reported of adult patients with EoE completing SFED with food reintroduction. The overall SFED histologic response was 54%, which increased to 58% with 1 additional round of dietary therapy, suggesting that 31% may respond in a second attempt. Most patients who completed food reintroduction had a single food trigger identified. Dietary elimination with specific food trigger identification is a feasible alternative to medical therapy for adults with EoE.

Current treatment options and long-term outcomes in patients with eosinophilic esophagitis

INTRODUCTION

Dietary and pharmacological (proton pump inhibitors, swallowed topical corticosteroids) therapies are effective for induction of clinical and histological remission of eosinophilic esophagitis. However, data evaluating their long-term efficacy and safety is limited.

AREAS COVERED

Since eosinophilic esophagitis is chronic, clinical, endoscopic, and histological features usually recur when successful treatments are stopped. In untreated patients, persistent esophageal eosinophilic inflammation may progress to fibrostenosis over time, giving place to strictures and narrow-caliber esophagi. This article comprehensively reviews available data on long-term maintenance of eosinophilic esophagitis with pharmacological and dietary treatment. It also discusses limitations re: available literature and outlines data gaps on adherence to therapy and monitoring disease activity in the long-term.

EXPERT OPINION

Evidence indicates that long-term maintenance therapy may decrease the risk of esophageal stricture, food bolus impaction, and need for dilation in patients with eosinophilic esophagitis. Further knowledge on eosinophilic esophagitis phenotypes is needed to ascertain who will benefit best from sustained therapy. Unanswered questions include an adequate definition for sustained remission, best strategies for maintenance drugs and diets, enhancement of treatment adherence, and proper monitoring for long-term surveillance.

Medical Management of Eosinophilic Esophagitis in Pediatric Patients

Eosinophilic esophagitis is an immune-mediated allergic disease of the esophagus that affects pediatric patients of all ages. The diagnosis is made by esophagogastroduodenoscopy demonstrating eosinophilic infiltrate of the esophagus. Approaches to treatment involve proton pump inhibitors (PPIs), swallowed topical steroid preparations, as well as dietary elimination. In this review we discuss the evidence and efficacy of each of these approaches.

Dietary treatment of eosinophilic gastrointestinal disorders in children

PURPOSE OF REVIEW

To provide an overview of recent developments on dietary treatment of eosinophilic gastrointestinal disorders (EGID) in children.

RECENT FINDINGS

Food antigens are the main triggers of eosinophilic esophagitis (EoE); however, currently available allergy tests cannot reliably identify eliciting antigens. Studies evaluating the six-food empiric elimination diet (6FED-milk, wheat/gluten, egg, soy/legumes, nuts and fish/seafood) have shown histological remission rates of 72%. Milk, egg, wheat/gluten, and, to a lesser extent, soy/legumes were the most frequent food triggers with only one or two culprit foods identified for most patients. A 4-food elimination strategy afforded a 64% remission rate. A step-up two-four-six food elimination diet generated a 43% remission rate at the two-food elimination stage, and similar reported rates for 4FED and 6FED. Endoscopic procedures were reduced by a 20% compared with 6FED. In a prospective study including 63 children, exclusive milk elimination has been effective in 44% of them. Controlled elimination and reintroduction with histological assessment is necessary.

SUMMARY

Dietary therapy of EoE has evolved from more restrictive to less restrictive diets to provide better balance between efficacy vs. nutritional deficiencies and quality of life. Data on efficacy of dietary therapy in other EGIDs are very scarce.