Vedolizumab Treatment May Reduce Steroid Burden and Improve Histology in Patients With Eosinophilic Gastroenteritis

Eosinophils, Eosinophilic Gastrointestinal Diseases, and Inflammatory Bowel Disease: A Critical Review

BACKGROUND/OBJECTIVES

Inflammatory bowel disease (IBD) and eosinophilic gastrointestinal diseases (EGIDs) are complex, multifactorial chronic inflammatory disorders affecting the gastrointestinal tract. Their epidemiology, particularly for eosinophilic esophagitis (EoE), is increasing worldwide, with a rise in the co-diagnosis of IBD and EGIDs. Both disorders share common risk factors, such as early exposure to antibiotics or specific dietary habits. Moreover, from a molecular perspective, eosinophilic infiltration is crucial in the diagnosis of eosinophilic disorders, and it also plays a pivotal role in IBD histological diagnosis. Indeed, recent evidence highlights the significant role of eosinophils in the health of the intestinal mucosal barrier and as mediators between innate and acquired immunity, even indicating a potential role in IBD pathogenesis. This narrative review aims to summarize the current evidence regarding the common clinical and molecular aspects of EGIDs and IBD and the current state of knowledge regarding overlap conditions and their pathogenesis.

METHODS

Pubmed was searched until May 2023 to assess relevant studies describing the epidemiology, pathophysiology, and therapy of EGIDs in IBD.

RESULTS

The immune pathways and mechanisms underlying both EGIDs and IBD remain partially known. An improved understanding of the role of eosinophils in overlapping conditions could lead to enhanced diagnostic precision, the development of more effective future therapeutic strategies, and a more accurate prediction of patient response. Consequently, the identification of red flags indicative of an eosinophilic disorder in IBD patients is of paramount importance and must be evaluated on a case-by-case basis.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Pharmacologic Management of Non-Eosinophilic Esophagitis Eosinophilic Gastrointestinal Diseases

Data for pharmacologic treatments for non-eosinophilic esophagitis (EoE) eosinophilic gastrointestinal diseases (EGIDs) are limited. Nevertheless, because of the increasing understanding of EGID pathogenesis, a number of medications are used to treat EGIDs, though all are currently off-label. Initial therapy generally starts with corticosteroids, and "topical" delivery is preferred over systemic due to long-term side effects. A number of other small molecules could potentially be used, ranging from allergy medications to immunosuppressants. Biologics are also being used and investigated for EGIDs and represent promising targeted therapies. Multiple therapeutic targets have also been identified, many of which overlap with EoE targets.

The Dual Lens of Endoscopy and Histology in the Diagnosis and Management of Eosinophilic Gastrointestinal Disorders-A Comprehensive Review

Eosinophilic Gastrointestinal Disorders (EGIDs) are a group of conditions characterized by abnormal eosinophil accumulation in the gastrointestinal tract. Among these EGIDs, Eosinophilic Esophagitis (EoE) is the most well documented, while less is known about Eosinophilic Gastritis (EoG), Eosinophilic Enteritis (EoN), and Eosinophilic Colitis (EoC). The role of endoscopy in EGIDs is pivotal, with applications in diagnosis, disease monitoring, and therapeutic intervention. In EoE, the endoscopic reference score (EREFS) has been shown to be accurate in raising diagnostic suspicion and effective in monitoring therapeutic responses. Additionally, endoscopic dilation is the first-line treatment for esophageal strictures. For EoG and EoN, while the literature is more limited, common endoscopic findings include erythema, nodules, and ulcerations. Histology remains the gold standard for diagnosing EGIDs, as it quantifies eosinophilic infiltration. In recent years, there have been significant advancements in the histological understanding of EoE, leading to the development of diagnostic scores and the identification of specific microscopic features associated with the disease. However, for EoG, EoN, and EoC, precise eosinophil count thresholds for diagnosis have not yet been established. This review aims to elucidate the role of endoscopy and histology in the diagnosis and management of the three main EGIDs and to analyze their strengths and limitations, their interconnection, and future research directions.

Duodenal stenosis, an unusual presentation of eosinophilic gastroenteritis: a case report

Eosinophilic gastrointestinal diseases (EGIDs) are rare, chronic inflammatory disorders characterized by eosinophilic infiltration of the gastrointestinal tract. Symptoms and clinical presentations vary depending on the site and layer of the gastrointestinal wall infiltrated by eosinophils. Gastrointestinal obstruction is a serious, though uncommon, presentation. Management can be extremely challenging because of the rarity of the condition and the lack of robust scientific evidence. Current treatment approaches for EGIDs mainly focus on elimination diets, proton pump inhibitors and corticosteroids, which present high refractoriness rates. Novel targeted therapies are being investigated but not routinely used. Surgery should be avoided as far as possible; however, it may be the only option in gastrointestinal obstruction when long-term remission cannot be attained by any medical strategy. Herein we report the case of an adolescent boy affected by an eosinophilic gastrointestinal disease with progressive duodenal stenosis, refractory to medical therapy, who successfully benefitted from surgical management. He presented with a one-year history of gastrointestinal obstructive symptoms with feeding intolerance. After the diagnostic workup, he was diagnosed with an eosinophilic gastrointestinal disease (esophagitis and enteritis) with a duodenal involvement causing a progressive duodenal stenosis. Due to refractoriness to the conventional medical therapies and the consequent high impact on his quality of life, related both to the need for enteral nutrition and repeated hospitalizations, we decided to perform a gastro-jejunum anastomosis, which allowed us to obtain a clinical and endoscopic long-term remission. The early discussion of the case and the involvement of all experienced specialists, pediatricians and pediatric surgeons is essential.

Joint ESPGHAN/NASPGHAN Guidelines on Childhood Eosinophilic Gastrointestinal Disorders Beyond Eosinophilic Esophagitis

INTRODUCTION

Eosinophilic gastrointestinal disorders beyond eosinophilic esophagitis (non-EoE EGIDs) are rare chronic inflammatory disorders of the gastrointestinal (GI) tract. Diagnosis is based on clinical symptoms and histologic findings of eosinophilic inflammation after exclusion of a secondary cause or systemic disease. Currently, no guidelines exist for the evaluation of non-EoE EGIDs. Therefore, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) formed a task force group to provide consensus guidelines for childhood non-EoE EGIDs.

METHODS

The working group was composed of pediatric gastroenterologists, adult gastroenterologists, allergists/immunologists, and pathologists. An extensive electronic literature search of the MEDLINE, EMBASE, and Cochrane databases was conducted up to February 2022. General methodology was used in the formulation of recommendations according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to meet current standards of evidence assessment.

RESULTS

The guidelines provide information on the current concept of non-EoE EGIDs, disease pathogenesis, epidemiology, clinical manifestations, diagnostic and disease surveillance procedures, and current treatment options. Thirty-four statements based on available evidence and 41 recommendations based on expert opinion and best clinical practices were developed.

CONCLUSION

Non-EoE EGIDs literature is limited in scope and depth, making clear recommendations difficult. These consensus-based clinical practice guidelines are intended to assist clinicians caring for children affected by non-EoE EGIDs and to facilitate high-quality randomized controlled trials of various treatment modalities using standardized, uniform disease definitions.

A Case of Refractory Eosinophilic Gastrointestinal Disease Successfully Treated With Dupilumab

Eosinophilic infiltration of the gastrointestinal (GI) tract beyond the esophagus is a rare condition in adults with limited data on treatment. Current treatments with steroids and diet modifications have shown benefit, but when these treatments fall short, there is little research-driven guidance for further recommendations. We present a case of eosinophilic GI disease with extensive involvement of the GI tract successfully treated with dupilumab after failure of traditional treatment occurred.

Non-esophageal eosinophilic gastrointestinal diseases: a narrative review

Eosinophilic gastrointestinal disorders are a group of rare diseases characterized by the infiltration of eosinophils in the gastrointestinal wall in a greater amount than in homeostatic conditions. 'Non-esophageal eosinophilic gastrointestinal disorders' is the umbrella term for all eosinophilic gastrointestinal disorders outside of the well known eosinophilic esophagitis. This includes eosinophilic gastritis, eosinophilic enteritis and eosinophilic colitis. The clinical presentation is atypical and not very different for the three disorders. The depth of infiltration has a bigger influence on the presenting symptoms than the disease location. Although the frequency of diagnosis and research in this subject is increasing over time, non-esophageal eosinophilic disorders are rare and high quality evidence is limited to date. In this narrative review, we provide an overview of the latest insights in the pathophysiology, diagnostic approach and available treatment options. Transcriptome studies have found the pathogenesis to be T helper type 2 driven. Various laboratory findings can be used to trigger raised suspicion and investigation with endoscopy. As the endoscopic appearance of the mucosa is normal in most cases, multiple biopsies in each segment are needed to quantify the amount of eosinophils in the tissue. Eosinophilic cut-offs for diagnosis are a controversial topic and a consensus is still lacking. A recently developed tissue based diagnostic platform which measures differentially expressed genes might be available in the future to classify patients with intermediate eosinophilic tissue levels under the cut-off. For the treatment, corticosteroids are still the cornerstone of treatment but promising research suggests a role of biologicals, such as Lirentelimab (anti-siglec 8) in particular.

Eosinophilic gastroenteritis: Pathogenesis, diagnosis, and treatment

ABSTRACT

Eosinophilic gastroenteritis (EGE) is a gastrointestinal disorder of unclear etiology that is characterized by eosinophilic infiltration of the stomach and small intestine, and consists of mucosal, muscular, and serosal subtypes. Eosinophilic infiltration of the gastrointestinal tract is a fundamental histopathological characteristic of EGE and is driven by several T-helper type 2 (Th2)-dependent cytokines and induced by food allergy. Due to the lack of a diagnostic gold standard, EGE has a high rate of delayed diagnosis or misdiagnosis. However, several new diagnostic strategies have been developed, such as novel genetic biomarkers and imaging tests. Although dietary therapy and corticosteroids remain the common choices for EGE treatment, recent decades have seen the emergence of novel treatment alternatives, such as biologics that target particular molecules involved in the pathogenic process. Preliminary investigations and clinical trials have demonstrated the efficacy of biologics and provided additional insights for the era of refractory or corticosteroid-dependent EGE biologics.

The role of biologics in pediatric food allergy and eosinophilic gastrointestinal disorders

Continuing insight into the molecular mechanisms of atopic disorders has enabled the development of biologics to precisely target these diseases. Food allergy (FA) and eosinophilic gastrointestinal disorders (EGIDs) are driven by similar inflammatory molecular mechanisms and exist along the same atopic disease spectrum. Therefore, many of the same biologics are being investigated to target key drivers of mechanisms shared across the disease states. The enormous potential of biologics for the treatment of FA and EGIDs is highlighted by the significant increases in the number of ongoing clinical trials (more than 30) evaluating their use in these disease states, as well as by the recent US Food and Drug Administration approval of dupilumab for the treatment of eosinophilic esophagitis. Here we discuss past and current research into the use of biologics in FA and EGIDs and their potential role in improving treatment options in the future, with the need to have biologics widely clinically available.

Refractory Malignant Eosinophilic Colitis Leading to Ischemic Colitis

Eosinophilic colitis (EC) is the most uncommon disease within the spectrum of eosinophilic gastrointestinal disorders. Currently, there are no well-established diagnostic criteria and no approved Food and Drug Administration therapies. We discuss a case of a 30-year-old man with refractory malignant EC leading to ischemic colitis. The patient was tried on multiple therapies, including a combination therapy of benralizumab and vedolizumab, which were unsuccessful. Unfortunately, the patient ultimately required a total proctocolectomy. More studies need to be performed to treat patients with severe refractory cases of EC.

Dupilumab Leads to Clinical Improvements including the Acquisition of Tolerance to Causative Foods in Non-Eosinophilic Esophagitis Eosinophilic Gastrointestinal Disorders

A recent report showed that most pediatric cases of non-eosinophilic esophagitis (EoE) eosinophilic gastrointestinal disorders (EGIDs) (non-EoE EGIDs) are persistent and severe compared with those of EoE, thus requiring further effective therapeutic approaches. In this study, we present the first case based on a systematic search of non-EoE EGID for which tolerance to causative foods and histological and symptomatic improvements were achieved following dupilumab administration, after elimination diets and omalizumab and mepolizumab treatments. Driven by this case, we investigated the efficacies of biological treatments in non-EoE EGID cases based on the patient studied herein, and other patients identified in the conducted systematic review. Seven articles, including five different biologics, were reviewed. Both clinical efficacies and impact differences among the targeted molecules are demonstrated in this study. Our findings show that dupilumab may affect mechanisms that can suppress symptoms induced by offending foods that are different from those induced by other biologics as identified in the conducted systematic review. Additional studies are required to address the unmet needs of non-EoE EGID treatments.

"Tickle me pink": update in eosinophilic gastrointestinal disorders

PURPOSE OF REVIEW

Eosinophilic gastrointestinal diseases (EGIDs) outside of the esophagus have been previously enigmatic and rare diagnoses. Fortunately, increasing research over the past few decades has led to an improved understanding of disease pathophysiology and epidemiology. This has been foundational for developing accurate nomenclature, diagnostic criteria, and therapeutics.

RECENT FINDINGS

This article will review recent updates in nonesophageal EGIDs. Accurate disease classification and nomenclature developed from international consensus are now available, as well as data challenging the notion that abnormal endoscopic findings are rare in this population. Studies on natural history, outcomes, and impact on patient quality of life are reviewed. Lastly, retrospective studies and clinical trials on EGID therapies are summarized.

SUMMARY

With a standardized nomenclature system for EGIDs now established, formal diagnostic guidelines and criteria for nonesophageal EGIDs are in active development. While management remains challenging compared with eosinophilic esophagitis, research and development of effective, steroid-sparing therapies (primarily through biologics and dietary therapy) remain underway. In eosinophilic colitis, the rarest EGID, research remains focused on illuminating pathophysiology. Ongoing research will continue to improve understanding of natural history, outcomes, and therapeutic options for these diseases.

Biologics in eosinophilic gastrointestinal diseases

Eosinophilic gastrointestinal diseases are a constellation of conditions categorized by the location of eosinophilic infiltration in the gastrointestinal tract. Symptoms vary based on location of eosinophils and age of the patient. There are no approved medications at the current time with individuals using off-label steroids or dietary therapy. Translational research has identified potential pathways to target in the treatment of eosinophilic esophagitis (EoE), gastritis (EoG), and enteritis (EoN), including type 2 pathways, mast cells, and eosinophils. Preliminary studies found cendakimab (anti-interleukin [IL]-13) and dupilumab (anti-IL-4 receptor alpha) to have an effect on eosinophil count and symptoms with dupilumab recently approved. In addition, mepolizumab (anti-IL-5), reslizumab (anti-IL-5), and lirentelimab (anti-Siglec 8) were found to have reduction in eosinophils without reduction of symptoms. For EoG and EoN, both benralizumab (anti-IL-5 receptor) and lirentelimab were found to have histologic and symptom improvement. There are no agents studied for eosinophilic colitis. Results of ongoing phase 3 trials in EoE and EoG/EoN are also anticipated.

Eosinophilic Gastrointestinal Diseases Beyond the Esophagus: An Evolving Field and Nomenclature

The eosinophilic gastrointestinal diseases (EGIDs) are a group of chronic, immune-mediated gastrointestinal (GI) diseases characterized by GI symptoms and pathologic eosinophilic infiltration of specific areas within the GI tract in the absence of secondary causes of eosinophilia. The non-eosinophilic esophagitis EGIDs remain understudied and likely underdiagnosed, owing in part to the lack of clarity in the terminology previously used to describe these diseases. The newly established EGID nomenclature framework includes a first-tier description of the specific location of GI tract involvement and a second-tier description with more granular characterizations of disease involvement. EGIDs can involve any segment or layer of the GI tract, so patients can present with a wide array of common, nonspecific GI symptoms. Diagnosing EGIDs requires endoscopic evaluation and biopsies showing increased eosinophilic tissue infiltration in the correct clinical context after ruling out other causes of eosinophilia. Although the pathogenesis is not yet fully understood, EGIDs are likely allergic conditions triggered by food antigen exposure. Most patients are currently treated with corticosteroids, but investigations of other pharmacologic and dietary therapies are ongoing. This article highlights the recently updated EGID nomenclature and summarizes the current understanding of the diagnosis, pathogenesis, and treatment of EGIDs.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Current and emerging therapies for eosinophilic esophagitis

Background: Eosinophilic esophagitis (EoE) is a Type-2 chronic inflammatory food antigen-driven disease of the esophagus, characterized by eosinophilic predominant inflammation and a constellation of symptoms. The incidence and prevalence of EoE has increased over the past 2 decades. There is an unmet need for approved less burdensome treatment options. Objective: To describe the underlying pathophysiology and diagnosis of EoE and discuss the currently available treatment options. We also aim to review the new and emerging therapies for EoE. Methods: A search of a medical literature data base was performed for articles that discuss treatment for EoE. Results: A comparison of current therapies showed that dietary elimination, swallowed topical corticosteroids, and proton-pump inhibitor therapy are all effective for different populations. Emerging therapies that were reviewed include new topical corticosteroids and biologics directed against Type 2 inflammation. Conclusion: EoE is a chronic inflammatory disorder that can be debilitating, with long-term sequelae. There are no current approved therapies in the United States. Numerous new treatments are on the horizon. Increasing amounts of data are helping to tailor treatment for each patient. Ultimately, shared decision-making is the best approach to guide treatment choices with patients to manage the ever-increasing burden of this disease.

Vedolizumab for the Treatment of Noninflammatory Bowel Disease Related Enteropathy

Vedolizumab has become an integral part of the therapeutic armamentarium for patients with inflammatory bowel disease (IBD) who have failed conventional medical therapy. Vedolizumab is an α4β7 integrin antagonist that inhibits intestinal T-cell translocation by blocking integrin interactions with mucosal vascular addressin cellular adhesion molecule 1, reducing lymphocyte-mediated inflammation.¹ Its gut selective mode of action and favorable safety profile have led to reports of off-label use for non-IBD-related inflammatory intestinal disorders, such as microscopic colitis,² and small intestinal inflammatory conditions including autoimmune enteropathy³ and common variable immune deficiency-related enteritis.⁴ Treatment of non-IBD-related enteropathies is challenging with no approved therapies or established treatment algorithms. We conducted a literature review to assess clinical, endoscopic, and histologic improvement in patients treated with vedolizumab for non-IBD enteropathies refractory to conventional therapy.

Type 2 Inflammation in Eosinophilic Esophagitis: From Pathophysiology to Therapeutic Targets

Eosinophilic esophagitis (EoE) is a chronic immune-mediated disease of the esophagus characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation, whose incidence is rising. It significantly affects patients’ quality of life and, if left untreated, results in fibrotic complications. Although broad consensus has been achieved on first-line therapy, a subset of patients remains non-responder to standard therapy. The pathogenesis of EoE is multifactorial and results from the complex, still mostly undefined, interaction between genetics and intrinsic factors, environment, and antigenic stimuli. A deep understanding of the pathophysiology of this disease is pivotal for the development of new therapies. This review provides a comprehensive description of the pathophysiology of EoE, starting from major pathogenic mechanisms (genetics, type 2 inflammation, epithelial barrier dysfunction, gastroesophageal reflux, allergens, infections and microbiota) and subsequently focusing on the single protagonists of type 2 inflammation (involved cells, cytokines, soluble effectors, surface proteins and transcription factors) that could represent present and future therapeutic targets, while summarizing previous therapeutic approaches in literature.

Pathophysiology of Non-IgE-Mediated Food Allergy

Non-IgE-mediated food allergies are a group of disorders characterized by subacute or chronic inflammatory processes in the gut. Unlike IgE mediated food allergies that may result in multi-organ system anaphylaxis, the non-IgE mediated food allergies primarily affect the gastrointestinal tract. This review outlines the clinical manifestations, epidemiology, pathophysiology, and management of non-IgE-mediated food allergies. An updated literature search of selected non-IgE-mediated food allergies was conducted for this review using PubMed database to the current year (2021). Reviewed disorders include food protein-induced enterocolitis syndrome (FPIES), food-protein enteropathy (FPE), food protein-induced allergic proctocolitis (FPIAP), and eosinophilic gastrointestinal disorders (EGIDs) such as eosinophilic esophagitis (EoE). While extensive gains have been made in understanding FPIES, FPIAP, FPE, and EoE, more information is needed on the pathophysiology of these food allergies. Similarities among them include involvement of innate immunity, T-lymphocyte processes, alteration of the intestinal lumen at the cellular level with the appearance of inflammatory cells and associated histologic changes, and specific cytokine profiles suggesting food-specific, T-cell, and immune-mediated responses. While FPIES and FPIAP typically resolve in early childhood, EGIDs typically do not. Emerging new therapies for EoE offer promise of additional treatment options. Further studies identifying the immunopathogenesis, associated biomarkers, and mechanisms of tolerance are needed to inform prevention, diagnosis and management.

Emerging Therapies for Eosinophilic Gastrointestinal Diseases

Besides eosinophilic esophagitis, other eosinophilic gastrointestinal diseases (EGIDs), such as eosinophilic gastritis, eosinophilic gastroenteritis, and eosinophilic colitis, are increasingly diagnosed over the last decade. Whereas diagnosis and therapy of eosinophilic esophagitis have been standardized, the diagnosis and therapy of other EGIDs are areas of active research. Motivated by the increasing prevalence of these conditions, concerted efforts of different stakeholders have led to the evaluation of targeted biologic therapies for EGID management over the last couple of years, and several promising molecules are currently in the pipeline. This review article provides an overview of targeted biologic therapies for use in EGIDs.

Eosinophilic Gastritis/Gastroenteritis

PURPOSE OF REVIEW

Eosinophilic gastritis/gastroenteritis (EG/EGE) are rare eosinophilic infiltrative disorders in children and adults that fall under the umbrella term eosinophilic gastrointestinal disorders (EGIDs). EGIDs also include eosinophilic esophagitis (EoE) and eosinophilic colitis. In this article, we present the current literature regarding the clinical presentation, diagnostic criteria, and management of EG/EGE.

RECENT FINDINGS

The underlying complex pathophysiology remains unknown, yet hypersensitivity response is a central component. Unlike EoE, standardized diagnostic criteria are lacking but, promising research employing tissue-based and blood-based methods of diagnosis have been reported. Non-EoE EGIDs are more challenging to treat than EoE. More than a third of patients may achieve spontaneous remission. Still, most will require dietary elimination and/or pharmaceutical interventions, mainly corticosteroids, but also biologics (monoclonal antibodies against IL-4, IL-5, TNFα, integrin α4β7, and IgE), mast-cell stabilizers, leukotriene (LT)-receptor antagonists, and antihistamines. Promising research suggests the role of AK002, an anti-siglec antibody, in clinical and histological improvement. Given the rarity and underdiagnosis of EG/EGE, different natural progression compared to EoE, heterogeneous clinical manifestations, and probable normal endoscopic appearance, it is vital to maintain a high suspicion index in atopic patients, obtain at least 5-6 random biopsies from each site for gastro/duodenal eosinophilic infiltrate with the subsequent exclusion of inflammatory, allergic and infectious differential diagnoses to increase the yield of an accurate diagnosis. Corticosteroids remain the mainstay of treatment, often requiring long-term use. Steroid-sparing agents remain experimental. Goals of therapy move beyond clinical remission but lack evidence to support histological remission.

Targeted Therapies for Eosinophilic Gastrointestinal Disorders

The growing recognition of eosinophilic gastrointestinal disorders has revealed the limitations of current treatment (mainly based on dietary modification and corticosteroids), and include refractoriness, high recurrence rates, and the need for long-term therapy. Research efforts, mainly in eosinophilic esophagitis (EoE), have unveiled essential pathophysiological mechanisms leading to these disorders, which bear some similarities to those of atopic manifestations and are shared by eosinophilic gastroenteritis (EGE) and eosinophilic colitis (EC). Novel targeted therapies, some imported from bronchial asthma and atopic dermatitis, are currently being assessed in EoE. The most promising are monoclonal antibodies, including those targeting interleukin (IL)-13 (cendakimab) and IL-4 (dupilumab), with phase 3 trials currently ongoing. The potential of anti-integrin therapy (vedolizumab) and Siglec-8 blockers (antolimab) in EGE are also promising. Non-biological therapies for eosinophilic gut disorders, which include preventing the activation of Janus kinase (JAK)-signal transducer and activator of transcription (STAT) and chemoattractant receptor expressed on T helper 2 cells (CRTH2) signaling pathways, and other potential targets that deserve investigation in eosinophilic gut disorders, are reviewed.

Eosinophilic esophagitis: from pathophysiology to management

Eosinophilic esophagitis (EoE) incidence and prevalence have sharply increased in the last decade; so, the management of these patients is changing rapidly. Standard regimens as elimination diet, proton pump inhibitors and topical swallowed steroids are not able to achieve remission in all patients. Moreover, loss of efficacy and safety concerns for long-term medical treatments are rising questions. As for other chronic immune-mediated diseases, biologics have been evaluated for the treatment of EoE. Several targets in the Th2-mediated inflammatory cascade with eosinophilic mucosal infiltration, have been tested with alternating results. This review provides a comprehensive discussion of the available studies evaluating biologics in EoE and the possible future options most desirable for these patients.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Safe and Successful Treatment of Acute Cellular Rejection of an Intestine and Abdominal Wall Transplant With Vedolizumab

Graft survival rates after intestinal transplantation (ITx) are still the lowest in comparison to other solid organ transplants. One of the main reasons is the frequent occurrence of acute cellular rejection (ACR). Vedolizumab is an antibody against α4β7⁺ integrin involved in gut-homing of T cells which has been approved for inflammatory bowel diseases (IBD). We report its off-label use to treat ACR after ITx.

Pharmacological treatments for eosinophilic esophagitis: current options and emerging therapies

Introduction: The epidemiology of eosinophilic esophagitis (EoE) has increased rapidly to represent a common cause of chronic and recurrent esophageal symptoms. Current treatment options have limitations so the development of novel therapies is a matter of growing interest.Areas covered: This article provides an up-to-date discussion of current therapies and investigational options for EoE. Established anti-inflammatory treatments for EoE at present include dietary therapy, proton pump inhibitors and swallowed topic steroids, which should be combined with endoscopic dilation in case of strictures. Refractoriness, high recurrence rates, and need for long-term therapies have promoted the investigation of novel, esophageal-targeted formulas of topic corticosteroids, and monoclonal antibodies (including mepolizumab, reslizumab, QAX576, RPC4046, dupilumab, omalizumab, infliximab, and vedolizumab) for EoE, with some having been demonstrated as effective and safe in the short term. Several additional promising therapies are also discussed.Expert opinion: Several therapeutic targets have shown efficacy and will be approved to treat EoE, especially corticosteroid-sparing options and those for patients with multiple Th2-associated diseases. Personalized therapeutic strategies for initial and maintenance treatments of EoE must be rationally designed, to reduce the burden of disease and answer meaningfully the needs of all stakeholders involved in EoE.

Future therapies for eosinophilic gastrointestinal disorders

OBJECTIVE

To review novel therapeutics in development for treatment of eosinophilic gastrointestinal disorders (EGIDs).

DATA SOURCES

Clinical trial data (clinicaltrials.gov) and literature search on PubMed.

STUDY SELECTIONS

Studies on treatment and clinical trials in EGIDs were included in this review.

RESULTS

During the past decade, significant progress has been made in understanding disease mechanisms in EGIDs. As a result, a variety of novel therapeutics have been developed for treatment of these disorders. Several monoclonal antibodies against targets, including interleukin (IL) 4, IL-5, IL-13, integrins, and siglec-8, have shown promise in early trials. Novel formulations of corticosteroids are also in development.

CONCLUSION

The field of EGID research has advanced rapidly, and disease-modifying therapeutics are closer to clinical application.

Eosinophilic gastrointestinal diseases - Pathogenesis, diagnosis, and treatment

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

Eosinophilic Gastroenteritis: Clinical Manifestation, Natural Course, and Evaluation of Treatment with Corticosteroids and Vedolizumab

BACKGROUND

Eosinophilic gastroenteritis (EGE) is a rare, chronic inflammatory condition of the gastrointestinal tract. Little is known about its natural history and treatment outcomes. The aims of our analysis were to describe clinical presentation, response to current medical treatments, and to evaluate the response of refractory EGE to anti-integrin therapy.

METHODS

Patients with confirmed diagnosis of EGE fulfilling the diagnostic criteria: (1) the presence of gastrointestinal symptoms, (2) dense eosinophilic infiltration of the gastrointestinal mucosa, and (3) exclusion of other conditions leading to gastrointestinal eosinophilia were included in this analysis. In patients non-responding to corticosteroids and/or anti-TNF treatment the integrin blocker vedolizumab was used.

RESULTS

EGE patients (n = 22) were predominantly female (63%) with a median age at diagnosis of 41.5 years. The most frequent symptoms were abdominal pain (100%), diarrhea (59%), nausea/vomiting (36%), and bloating (27%). No pathognomonic endoscopic alterations were found. Eosinophilic infiltration was observed in the majority of patients in more than one segment. Patients were treated with systemic steroids, topical, and enteral release steroids in 21/22 (95%) patients, proton pump inhibitors in 7/22 (32%), TNFα inhibitors in 3/22 (14%), and vedolizumab in 4/22 (18%) patients. In 3/4 of steroid-refractory patients vedolizumab induced a clinical and histological improvement.

CONCLUSIONS

The combination of highly variable clinical presentation, subtle endoscopic abnormalities, and involvement of several GI segments undermines the difficulty to diagnose EGE and the need for structured biopsy sampling. Corticosteroids were efficient in the majority of patients to induce remission. Response to the integrin blocker vedolizumab suggests further assessment in refractory cases.

Clinical analysis of eosinophilic gastroenteritis

AIM

To analyze the clinical features, diagnosis, and prognosis of eosinophilic gastroenteritis (EG).

METHODS

A retrospective analysis was performed of clinical data of 88 cases with EG at our hospital between June 2013 and August 2018.

RESULTS

Eighty-eight patients were included, with a male to female ratio of 1.2:1. The patients ranged in age from 14 to 73 years, with a mean age 45.1 years. Abdominal pain was the most common symptom, 73.3% of patients had positive allergen screening results, and some patients had negative endoscopic findings. Common endoscopic abnormalities were mainly congestion, erosion, ulcers, polyps and so on, and pathological examination revealed a large number of eosinophils infiltrated in the gastrointestinal tract, with the highest average value detected in the cecum. Treatment with proton pump inhibitors was effective. Glucocorticoid therapy was useful, but the disease could recur.

CONCLUSION

The pathogenesis of EG is still unclear, although it is known that allergens play an important role in it. The clinical manifestations are atypical. An increase of eosinophilic granulocytes in peripheral blood and bone marrow smear can support the diagnosis. Imaging and endoscopic manifestations are not specific. Pathology is the key to diagnosis. Glucocorticoid therapy can obtain good results, but there have been no unified criteria on the specific dosage and course of treatment .

Biological therapies for eosinophilic gastrointestinal diseases

The scientific basis and the clinical application of mAb therapies that target specific immunologic pathways for eosinophilic gastrointestinal diseases are areas of active interest. There is a growing recognition of a subset of patients with eosinophilic esophagitis whose disease does not respond well to topical steroids or elimination diets. In addition, long-term use of corticosteroids presents possible risks that are currently being evaluated. Systemic therapy with a biologic agent offers potential advantages as a global approach that could limit the need for multiple, locally active medical therapies and allergen avoidance. The identification of novel biologic strategies is ongoing, and the recent validation of instruments and outcome measures to assess disease activity has proved essential in demonstrating efficacy. Studies using biologics that target IL-13 pathways in the treatment of eosinophilic esophagitis have demonstrated substantial promise.