Anti-IgE treatment of eosinophil-associated gastrointestinal disorders

Advancements in Biologic Therapies for Eosinophilic Gastrointestinal Diseases: A Comprehensive Review

Eosinophilic gastrointestinal diseases (EGIDs) encompass a group of disorders characterized by an abnormal accumulation of eosinophils in various parts of the gastrointestinal tract. EGIDs present with a wide range of symptoms such as abdominal pain, vomiting, diarrhea, difficulty swallowing, and food impaction. Monoclonal antibodies, targeting inflammatory cytokines or eosinophils, are the next emerging therapy for EGIDs. The only Food and Drug Administration-approved monoclonal antibody is dupilumab, and it has been approved for the treatment of eosinophilic esophagitis (EoE). In this article, the authors will discuss biologics that have been used in the treatment of eosinophilic gastrointestinal diseases.

Animal models of eosinophilic esophagitis

Eosinophilic esophagitis is a chronic inflammatory disorder of the esophagus. Over the past 25 yr, great strides have been made toward understanding its pathogenesis, in part due to studies in several types of animal models. The vast majority of these models have been characterized in mice. In this review, we summarize the histopathological features of eosinophilic esophagitis recapitulated by these animal models, as well as discuss their strengths and weaknesses.

Common and disparate clinical presentations and mechanisms in different eosinophilic gastrointestinal diseases

Eosinophilic gastrointestinal diseases (EGIDs) are a group of diseases characterized by selective eosinophil infiltration of the gastrointestinal (GI) tract in the absence of other causes of eosinophilia. These diseases are generally driven by type 2 inflammation, often in response to food allergen exposure. Among all EGIDs, the clinical presentation often includes a history of atopic disease with a variety of GI symptoms. EGIDs are traditionally separated into eosinophilic esophagitis (EoE) and non-EoE EGIDs. EoE is relatively better understood and now associated with clinical guidelines and 2 US Food and Drug Administration-approved treatments, whereas non-EoE EGIDs are rarer and less well-understood diseases without US Food and Drug Administration-approved treatments. Non-EoE EGIDs are further subclassified by the area of the GI tract that is involved; they comprise eosinophilic gastritis, eosinophilic enteritis (including eosinophilic duodenitis), and eosinophilic colitis. As with other GI disorders, the disease presentations and mechanisms differ depending on the involved segment of the GI tract; however, the differences between EoE and non-EoE EGIDs extend beyond which GI tract segment is involved. The aim of this article is to summarize the commonalities and differences between the clinical presentations and disease mechanisms for EoE and non-EoE EGIDs.

Pathophysiology of Non-Esophageal Eosinophilic Gastrointestinal Disorders

Eosinophilic gastrointestinal disorder (EGID) is an umbrella term encompassing a group of chronic, immune-mediated disorders characterized by eosinophil-rich inflammation affecting one or more segments of the gastrointestinal tract. A recent consensus in nomenclature and emerging data made possible through multi-center consortia are beginning to unravel the molecular and cellular underpinnings of EGIDs below the esophagus. These emerging findings are revealing both overarching commonalities related to a food allergen-driven, chronic, Th2-mediated immune response as well as location-specific nuances in the pathophysiology of the collective EGIDs. Altogether, these advances offer promise for improved diagnoses and more efficacious interventional strategies.

Eosinophilic gastritis and gluten-sensitive enteropathy manifested as hypoproteinemia and treated with omalizumab: a case report

BACKGROUND

Eosinophilic gastritis (EoG) has rarely been reported in conjunction with gluten-sensitive enteropathy (GSE). When this does occur, patients typically present with gastrointestinal symptoms. To our knowledge, hypoproteinemia has not been reported as the primary manifestation. Anti-IgE therapy, such as omalizumab, lowers eosinophil counts in the blood, lungs, and gut. Its efficiency in treating active EoG remain unknown.

CASE PRESENTATION

We report a 33-month-old boy with a history of food allergy and atopic dermatitis who developed recurrent edema, hypoproteinemia, and eosinophilia at the age of 14 months. The diagnoses of EoG and GSE were confirmed based on the clinical presentation and results of gastrointestinal biopsies and serological testing. Although prednisone and dietary intervention were initially effective, the boy developed prednisone-related facial swelling. After stopping prednisone, his symptoms relapsed. Subsequent treatment with omalizumab, combined with dietary intervention, showed good efficacy and safety.

CONCLUSIONS

To our knowledge, this is the first case of concurrent EoG and GSE that presented primarily with hypoproteinemia. We highlight the rare manifestations of these two diseases to raise clinical suspicion and prevent missed and delayed diagnoses. The pathogenesis of EoG is heterogeneous and complex. Omalizumab showed good efficacy, indicating that IgE-mediated processes may be involved in the pathogenesis of this patient's diseases.

Review article: Emerging insights into the epidemiology, pathophysiology, diagnostic and therapeutic aspects of eosinophilic oesophagitis and other eosinophilic gastrointestinal diseases

BACKGROUND

Eosinophilic gastrointestinal diseases (EGIDs) are chronic, immune-mediated disorders characterised clinically by gastrointestinal symptoms and histologically by a pathologic increase in eosinophil-predominant inflammation in the gastrointestinal tract, in the absence of secondary causes of eosinophilia.

AIMS

To highlight emerging insights and research efforts into the epidemiology, pathophysiology, diagnostic and therapeutic aspects of eosinophilic oesophagitis (EoE) and non-EoE EGIDs, and discuss key remaining knowledge gaps.

METHODS

We selected and reviewed original research, retrospective studies, case series, randomised controlled trials, and meta-analyses.

RESULTS

Standardised nomenclature classifies EGIDs as EoE, eosinophilic gastritis (EoG), eosinophilic enteritis (EoN), and eosinophilic colitis (EoC). Incidence and prevalence of EoE are rising, emphasising the need to better understand how environmental risk factors and genetic features interact. Advances in understanding EoE pathophysiology have led to clinical trials of targeted therapy and the approval (in the United States) of dupilumab for EoE. Several therapies that are under investigation hope to satisfy both histologic and clinical targets. For non-EoE EGIDs, efforts are focused on better defining clinical and histopathologic disease determinants and natural history, as well as establishing new therapies.

CONCLUSIONS

Unmet needs for research are dramatically different for EoE and non-EoE EGIDs. In EoE, non-invasive diagnostic tests, clinicopathologic models that determine the risk of disease progression and therapeutic failure, and novel biologic therapies are emerging. In contrast, in non-EoE EGIDs, epidemiologic trends, diagnostic histopathologic thresholds, and natural history models are still developing for these more rare disorders.

Long-term prognosis and its associated predictive factors in patients with eosinophilic gastroenteritis

BACKGROUND

Eosinophilic gastroenteritis (EGE) is a chronic recurrent disease with abnormal eosinophilic infiltration in the gastrointestinal tract. Glucocorticoids remain the most common treatment method. However, disease relapse and glucocorticoid dependence remain notable problems. To date, few studies have illuminated the prognosis of EGE and risk factors for disease relapse.

AIM

To describe the clinical characteristics of EGE and possible predictive factors for disease relapse based on long-term follow-up.

METHODS

This was a retrospective cohort study of 55 patients diagnosed with EGE admitted to one medical center between 2013 and 2022. Clinical records were collected and analyzed. Kaplan-Meier curves and log-rank tests were conducted to reveal the risk factors for long-term relapse-free survival (RFS).

RESULTS

EGE showed a median onset age of 38 years and a slight female predominance (56.4%). The main clinical symptoms were abdominal pain (89.1%), diarrhea (61.8%), nausea (52.7%), distension (49.1%) and vomiting (47.3%). Forty-three (78.2%) patients received glucocorticoid treatment, and compared with patients without glucocorticoid treatments, they were more likely to have elevated serum immunoglobin E (IgE) (86.8% vs 50.0%, P = 0.022) and descending duodenal involvement (62.8% vs 27.3%, P = 0.046) at diagnosis. With a median follow-up of 67 mo, all patients survived, and 56.4% had at least one relapse. Six variables at baseline might have been associated with the overall RFS rate, including age at diagnosis < 40 years [hazard ratio (HR) 2.0408, 95% confidence interval (CI): 1.0082-4.1312, P = 0.044], body mass index (BMI) > 24 kg/m2 (HR 0.3922, 95%CI: 0.1916-0.8027, P = 0.014), disease duration from symptom onset to diagnosis > 3.5 mo (HR 2.4725, 95%CI: 1.220-5.0110, P = 0.011), vomiting (HR 3.1259, 95%CI: 1.5246-6.4093, P = 0.001), total serum IgE > 300 KU/L at diagnosis (HR 0.2773, 95%CI: 0.1204-0.6384, P = 0.022) and glucocorticoid treatment (HR 6.1434, 95%CI: 2.8446-13.2676, P = 0.003).

CONCLUSION

In patients with EGE, younger onset age, longer disease course, vomiting and glucocorticoid treatment were risk factors for disease relapse, whereas higher BMI and total IgE level at baseline were protective.

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.

Eosinophils-from cradle to grave: An EAACI task force paper on new molecular insights and clinical functions of eosinophils and the clinical effects of targeted eosinophil depletion

Over the past years, eosinophils have become a focus of scientific interest, especially in the context of their recently uncovered functions (e.g. antiviral, anti-inflammatory, regulatory). These versatile cells display both beneficial and detrimental activities under various physiological and pathological conditions. Eosinophils are involved in the pathogenesis of many diseases which can be classified into primary (clonal) and secondary (reactive) disorders and idiopathic (hyper)eosinophilic syndromes. Depending on the biological specimen, the eosinophil count in different body compartments may serve as a biomarker reflecting the underlying pathophysiology and/or activity of distinct diseases and as a therapy-driving (predictive) and monitoring tool. Personalized selection of an appropriate therapeutic strategy directly or indirectly targeting the increased number and/or activity of eosinophils should be based on the understanding of eosinophil homeostasis including their interactions with other immune and non-immune cells within different body compartments. Hence, restoring as well as maintaining homeostasis within an individual's eosinophil pool is a goal of both specific and non-specific eosinophil-targeting therapies. Despite the overall favourable safety profile of the currently available anti-eosinophil biologics, the effect of eosinophil depletion should be monitored from the perspective of possible unwanted consequences.

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.

Review of Non-Eosinophilic Esophagitis-Eosinophilic Gastrointestinal Disease (Non-EoE-EGID) and a Case Series of Twenty-Eight Affected Patients

Eosinophilic gastrointestinal disease (EGID) is divided into eosinophilic esophagitis (EoE) and non-eosinophilic esophagitis eosinophilic gastrointestinal disease (non-EoE-EGID) based on the involved gastrointestinal segments. Reports regarding non-EoE-EGID are limited, in part because of its rarity. The present study was performed to review non-EoE-EGID, including its pathogenesis, diagnosis, treatment, and prognosis. Additionally, details regarding 28 cases of non-EoE-EGID recently diagnosed at our Japanese tertial medical center are presented and compared with 20 EoE cases diagnosed during the same period at the same medical center. Comparisons of the two groups clarified differences regarding age- and gender-dependent prevalence between the two conditions, and also showed that systemic involvement and disease severity were greater in the non-EoE-EGID patients. Notably, diagnosis of non-EoE-EGID is difficult because of its lack of specific or characteristic symptoms and endoscopic findings. The clinical characteristics of EoE and non-EoE-EGID differ in many ways, while they also share several genetic, clinical, laboratory, and histopathological features.

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.

Management of eosinophil-associated inflammatory diseases: the importance of a multidisciplinary approach

Elevated eosinophil counts in blood and tissue are a feature of many pathological processes. Eosinophils can migrate and accumulate in a wide variety of tissues and, by infiltrating a target organ, can mediate the development of several inflammatory diseases. The normalization of eosinophilia is a common biomarker of a treatable trait and can also be used as a prognostic and predictive biomarker since it implies a reduction in type 2 inflammation that contributes to disease pathogenesis. Biological therapies targeting this cell type and its proinflammatory mediators have been shown to be effective in the management of a number of eosinophilic diseases, and for this reason they constitute a potential common strategy in the treatment of patients with various multimorbidities that present with type 2 inflammation. Various biological options are available that could be used to simultaneously treat multiple target organs with a single drug, bearing in mind the need to offer personalized treatments under the umbrella of precision medicine in all patients with eosinophil-associated diseases (EADs). In addition to reviewing these issues, we also discuss a series of perspectives addressing the management of EAD patients from a multidisciplinary approach, with the collaboration of health professionals from different specialties who manage the different multimorbidities that frequently occur in these patients. We examine the basic principles of care that this multidisciplinary approach must cover and present a multidisciplinary expert opinion regarding the ideal management of patients with EADs, from diagnosis to therapeutic approach and follow-up.

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.

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.

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.

Treatment of primary eosinophilic colitis using immunoglobulin/histamine complex

Primary eosinophilic colitis (PEC) is a primary eosinophilic gastrointestinal disorder, and immunoglobulin/histamine complex (IHC) may be an effective therapeutic for PEC. IHC has a nonallergen-specific antinociceptive effect in the treatment of histamine-mediated pain.

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.

Single-cell RNA sequencing of mast cells in eosinophilic esophagitis reveals heterogeneity, local proliferation, and activation that persists in remission

BACKGROUND

Mast cells (MCs) are pleiotropic cells that accumulate in the esophagus of patients with eosinophilic esophagitis (EoE) and are thought to contribute to disease pathogenesis, yet their properties and functions in this organ are largely unknown.

OBJECTIVES

This study aimed to perform a comprehensive molecular and spatial characterization of esophageal MCs in EoE.

METHODS

Esophageal biopsies obtained from patients with active EoE, patients with EoE in histologic remission, and individuals with histologically normal esophageal biopsies and no history of esophageal disease (ie, control individuals) were subject to single-cell RNA sequencing, flow cytometry, and immunofluorescence analyses.

RESULTS

This study probed 39,562 single esophageal cells by single-cell RNA sequencing; approximately 5% of these cells were MCs. Dynamic MC expansion was identified across disease states. During homeostasis, TPSAB1^highAREG^high resident MCs were mainly detected in the lamina propria and exhibited a quiescent phenotype. In patients with active EoE, resident MCs assumed an activated phenotype, and 2 additional proinflammatory MC populations emerged in the intraepithelial compartment, each linked to a proliferating MKI67^high cluster. One proinflammatory activated MC population, marked as KIT^highIL1RL1^highFCER1A^low, was not detected in disease remission (termed "transient MC"), whereas the other population, marked as CMA1^highCTSG^high, was detected in disease remission where it maintained an activated state (termed "persistent MC"). MCs were prominent producers of esophageal IL-13 mRNA and protein, a key therapeutic target in EoE.

CONCLUSIONS

Esophageal MCs comprise heterogeneous populations with transcriptional signatures associated with distinct spatial compartmentalization and EoE disease status. In active EoE, they assume a proinflammatory state and locally proliferate, and they remain activated and poised to reinitiate inflammation even during disease remission.

Probiotics partially attenuate the severity of acute kidney injury through an immunomodulatory effect

Background

A healthy microbiome helps maintain the gut barrier and mucosal immune tolerance. Previously, we demonstrated that acute kidney injury (AKI) provoked dysbiosis, gut inflammation, and increased permeability. Here, we investigated the renoprotective effects of the probiotic Bifidobacterium bifidum BGN4 and the underlying mechanisms thereof.

Methods

C57BL/6 mice were subjected to bilateral renal ischemia-reperfusion injury (IRI) or sham operation. In the probiotic-treated group, BGN4 was administered by gavage once daily, starting 2 weeks before injury.

Results

Administration of BGN4 significantly increased gut microbiome diversity and prevented expansion of the Enterobacteriaceae and Bacteroidetes that were the hallmarks of AKI-induced dysbiosis. Further, BGN4 administration also significantly reduced other IRI-induced changes in the colon microenvironment, including effects on permeability, apoptosis of colon epithelial cells, and neutrophil and proinflammatory macrophage infiltration. Mononuclear cells co-cultured with BGN4 expressed significantly increased proportions of CD103⁺/CD11c⁺ and CD4⁺ CD25⁺ Treg cells, suggesting a direct immunomodulatory effect. BGN4 induced Treg expansion in colon, mesenteric lymph nodes (MNL), and kidney. BGN4 also reduced CX₃CR₁^intermediateLy6C^high monocyte infiltration and interleukin (IL)-17A suppression in the small intestine, which may have attenuated AKI severity, kidney IL-6 messenger RNA expression, and AKI-induced liver injury.

Conclusion

Prior supplementation with BGN4 significantly attenuated the severity of IRI and secondary liver injury. This renoprotective effect was associated with increased Foxp3 and reduced IL-17A expression in the colon, MNL, and kidney, suggesting that BGN4-induced immunomodulation might contribute to its renoprotective effects. Probiotics may therefore be a promising strategy to reduce AKI severity and/or remote organ injury.

Eosinophilic enteritis with enteroliths: A diagnostic dilemma

Introduction and importance

Eosinophilic gastroenteritis (EG) is a rare disease, characterized by eosinophilic infiltration of different layers of intestinal wall. Thus having a wide spectrum of presentation leading to diagnostic dilemma.

Case presentation

We report a case of 55 years old female who presented with pain in abdomen, constipation, vomiting off and on with passage of stools on alternate days since 6 months. Plain radiographs showed radio-opaque densities in abdomen. Contrast enhanced computed tomography (CECT) of abdomen showed Ileal stricture with dilated proximal bowel loops with enteroliths. Exploratory laparotomy confirmed ileal stricture with thickening of the mesentery and an ileal diverticulum. Resection of ileal stricture was performed. The resected segment contained seven hard, black enteroliths. Histopathology of the resected specimen confirmed EG. Stone analysis showed dense faecal matter with bile salts.

Clinical discussion

EG leads to symptoms ranging from vomiting, abdominal pain, diarrhoea, blood loss in stools, anaemia to malabsorption resulting in diagnostic dilemma. It may cause gastrointestinal obstructive symptoms secondary to stricture, depending upon the predominant layer involved.

Conclusion

The differential diagnosis of EG should always be considered when dealing with gastroenteritis presenting with radio-opaque densities in abdomen.

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Eosinophilic Gastroenteritis (EG) is a rare disease with a wide spectrum of clinical presentation.

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Diagnosis of EG is often missed or delayed due to its overlapping findings with other GI disorders.

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Presentation of Eosinophilic Gastroenteritis with Enterolith is rare.

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Eosinophilic Gastroenteritis once diagnosed can be treated medically.

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However, once stricture or enteroliths are formed or there is intestinal obstruction, surgery is the mainstay of treatment.

Recent update on the management of anaphylaxis

Anaphylaxis is a life-threatening systemic allergic reaction presenting various clinical manifestations. Its prevalence has increased in almost all age groups and both sexes. Food, venom, and drugs are major causes in both children and adults; a higher prevalence of food-induced anaphylaxis is noted in children, while a higher prevalence of drug-induced anaphylaxis is noted in adults. The pathogenic mechanism is mediated by immunologic and nonimmunologic mechanisms, where mast cells and basophils are key cells that release mediators. A diagnosis of anaphylaxis is mainly based on clinical symptoms and physical findings; however, an increased serum tryptase level is a useful biomarker. Epinephrine is the first-line drug to treat acute symptoms, and an epinephrine auto-injector should be prescribed for each patient. Antihistamines and systemic corticosteroids are used to relieve symptoms. This review updates current issues in the management of anaphylaxis as well as the new guidelines for proper diagnosis and treatment.

A case report about eosinophilic enteritis presenting as abdominal pain

RATIONALE

Eosinophilic enteritis (EE) is an immune-mediated antigen-driven disease that may lead to clinical symptoms and organ dysfunction and characterized by the presence of extensive eosinophilic infiltrates on histopathological examination of the intestinal mucosa.

PATIENT CONCERNS

A 29-year-old man presented with a half-month duration of paroxysmal upper abdominal pain that gradually evolved into continuous pain accompanied by the urge to defecate.

DIAGNOSES

Pathological findings of enteroscopy showed acute and chronic inflammation accompanied by eosinophilic infiltration (>20/ high-power field).

INTERVENTIONS

The patient was initially treated with IV infusion of dexamethasone 10 mg per day for 3 days, which was reduced to 7.5 mg per day for 2 days once pain relief was achieved. Upon discharged from our hospital, the patient was prescribed with oral prednisolone 30 mg per day, which was reduced by 5 mg per week for 6 weeks until discontinuation.

OUTCOMES

The patient was relieved from the pain after receiving dexamethasone for 5 days, and he was maintained on oral prednisolone 30 mg per day upon discharge from the hospital. On the day of discharge, the eosinophil count and derived ratios were normal.

LESSONS

In patients with EE, the dynamic changes of the eosinophil count should be monitored. Clinicians must be aware that not all patients with EE have a history of allergies. In the management and treatment of the disease, multisite biopsies should be carried out if EE is suspected, and EE is responsive to steroid therapy.

Gene therapy for a murine model of eosinophilic esophagitis

BACKGROUND

Eosinophils are specialized granulocytic effector cells that store and release highly active mediators used in immune defense. Eosinophils are also implicated in the pathogenesis of allergic disorders, including eosinophilic esophagitis (EoE), a chronic disorder characterized by infiltration of eosinophils into the esophagus and release of mediators that damage tissue, resulting in gastrointestinal morbidity, food impaction, and dysphagia. Treatment with elimination diets and/or topical corticosteroid therapy slow disease progression, but are complicated by adverse effects, limited compliance, and loss of response to therapy. We hypothesized that a single administration of an adeno-associated virus (AAV) coding for an anti-eosinophil monoclonal antibody that induces eosinophil clearance (anti-Siglec-F) would treat on a persistent basis a murine model of EoE.

METHODS

A mouse model of peanut-induced EoE that mimics the human disease was established by sensitization and challenge with peanut extract. After challenge, these mice exhibited an EoE phenotype demonstrated by elevated levels of blood eosinophils, infiltration of eosinophils in the esophagus with associated esophageal remodeling and food impaction.

RESULTS

The mice were treated with a single intravenous administration (10¹¹ genome copies) of AAVrh.10mAnti-Eos, a serotype rh.10 AAV vector coding for an anti-Siglec-F monoclonal antibody. Vector administration resulted in persistent, high levels of anti-Siglec-F antibody expression. Administration of AAVrh.10mAnti-Eos to the mouse model of EoE reduced blood (P < 0.02) and esophageal eosinophil numbers (P < 0.002) protected from esophageal tissue remodeling and minimized food impaction.

CONCLUSION

These results suggest that a single treatment with AAVrh.10mAnti-Eos has the potential to provide persistent therapeutic benefit to patients with EoE.

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.

Update on the Role of Allergy in Pediatric Functional Abdominal Pain Disorders: A Clinical Perspective

Both functional abdominal pain disorders (FAPDs) and food allergies are relatively common in children and adolescents, and most studies report an association between FAPDs and allergic conditions. FAPDs share pathophysiologic processes with allergies, including both immune and psychological processes interacting with the microbiome. No conclusive data are implicating IgE-mediated reactions to foods in FAPDs; however, there may be patients who have IgE reactions localized to the gastrointestinal mucosa without systemic symptoms that are not identified by common tests. In FAPDs, the data appears stronger for aeroallergens than for foods. It also remains possible that food antigens initiate an IgG reaction that promotes mast cell activation. If a food allergen is identified, the management involves eliminating the specific food from the diet. In the absence of systemic allergic symptoms or oral allergy syndrome, it appears unlikely that allergic triggers for FAPDs can be reliably identified by standard testing. Medications used to blunt allergic reactions or symptomatically treat allergic reactions may be useful in FAPDs. The purpose of the current manuscript is to review the current literature regarding the role of allergy in FAPDs from a clinical perspective, including how allergy may fit in the current model of FAPDs.

The use of biologics in food allergy

BACKGROUND

Food allergy continues to pose problems due to its increased frequency and its increasingly high severity. In this context, alongside the traditional avoidance strategies of allergenic foods and desensitization through the cautious progression of exposure to foods in the context of oral immunotherapy (OIT), alternative strategies have made their way in the last decades. We review the possibilities of intervention in food allergy with the use of biological drugs capable of interfering with the synthesis of IgE, with their mechanisms of action, or with complex biological mechanisms that lead to the establishment of a food allergy.

METHODS

Repeated Entrez PubMed searches using the template algorithm "Food allergy" and "biologics" or "Omalizumab" or "Dupilumab" or "milk desensitization" or "oral tolerance induction" or "oral immunotherapy" or "Etokimab" or "Tezepelumab" or "Quilizumab" or "Ligelizumab" or "Tralokinumab" or "Nemolizumab" or "Mepolizumab" or "Reslizumab" or "Benralizumab". The authors' clinical experience in paediatric allergy units of University hospitals was also drawn upon.

RESULTS

The landscape in this context has changed dramatically over the past 10 years. We have acquired knowledge mainly on the effect of different types of anti-IgE treatments in poliallergic patients with food allergy, and in patients treated with OIT. However, other mediators are being targeted by specific biologic treatments. Among them, the alarmins Il-33 and TSLP, IL-4 and IL-13, eosinophil-related molecules as IL-6, IL-8, IL-10, IL-12, and mostly IL-5, and integrins involved in the pathogenesis of eosinophilic gastrointestinal diseases (EGIDs), as SIGLEC-8.

CONCLUSIONS

The ever-better knowledge of the mechanisms of food allergy allowing these developments will improve not only the perspective of patients with the most serious immediate food allergies such as anaphylaxis, but also those of patients with related diseases such as atopic dermatitis, eosinophilic esophagitis, and EGIDs. Biologics are also intended to complement OIT strategies that have developed over the years.

Pancreaticoduodenectomy for stricturing primary eosinophilic duodenitis

A 59-year-old woman was referred to a specialist gastroenterologist following a year of intermittent abdominal bloating and worsening reflux. In the month prior to referral, the patient developed intermittent large volume vomiting consisting of bile-stained undigested food. This was accompanied by a 10 kg weight loss. Imaging and endoscopic investigations showed a circumferential thickening of the second part of the duodenum. Biopsy showed non-specific inflammatory changes with marked eosinophilic infiltrates. A pancreaticoduodenectomy was performed. Histopathological analysis of the resection sample showed primary eosinophilic duodenitis with no evidence of malignancy. Immunological testing was only positive for coeliac disease and an infectious cause was never identified. The patient's symptoms resolved following the surgery and she was discharged from surgical follow-up after 8 years of no further symptoms.

Chronic Rhinosinusitis with Nasal Polyps: Targeting IgE with Anti-IgE Omalizumab Therapy

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a complex, clinically heterogeneous and persistent inflammatory disorder of the upper airway. Detailed mechanistic insights into disease pathogenesis are lacking, but it is now accepted that local tissue IgE driven T2-high inflammatory pathways are critical to disease. The recent CRSwNP Phase 3 POLYP1 and POLYP2 replicate studies of blocking IgE with omalizumab confirmed rapid improvements in all clinical parameters of sinonasal disease, confirming a pivotal role for IgE driven inflammatory pathways in CRSwNP. This review summarises the biology of IgE in relation to CRSwNP. Insight into how IgE may drive CRSwNP is evaluated in the context of clinical improvements seen with omalizumab. The need for further studies using a broader patient and biomarker specific groups to aid more precise drug-patient selection alongside more detailed mechanistic studies of omalizumab in CRSwNP is highlighted.

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.

Anti-Siglec-8 Antibody for Eosinophilic Gastritis and Duodenitis

BACKGROUND

Eosinophilic gastritis and duodenitis are characterized by gastrointestinal mucosal eosinophilia, chronic symptoms, impaired quality of life, and a lack of adequate treatments. Mast-cell activity may contribute to the pathogenesis of the conditions. AK002 (lirentelimab) is an anti-Siglec-8 antibody that depletes eosinophils and inhibits mast cells and that has shown potential in animal models as a treatment for eosinophilic gastritis and duodenitis.

METHODS

In this phase 2 trial, we randomly assigned adults who had symptomatic eosinophilic gastritis, eosinophilic duodenitis, or both conditions in a 1:1:1 ratio to receive four monthly infusions of low-dose AK002, high-dose AK002, or placebo. The primary end point was the change in gastrointestinal eosinophil count from baseline to 2 weeks after the final dose; to maximize statistical power, we evaluated this end point in the placebo group as compared with the combined AK002 group. Secondary end points were treatment response (>30% reduction in total symptom score and >75% reduction in gastrointestinal eosinophil count) and the change in total symptom score.

RESULTS

Of the 65 patients who underwent randomization, 43 were assigned to receive AK002 and 22 were assigned to receive placebo. The mean percentage change in gastrointestinal eosinophil count was -86% in the combined AK002 group, as compared with 9% in the placebo group (least-squares mean difference, -98 percentage points; 95% confidence interval [CI], -121 to -76; P<0.001). Treatment response occurred in 63% of the patients who received AK002 and in 5% of the patients who received placebo (difference, 58 percentage points; 95% CI, 36 to 74; P<0.001). The mean change in total symptom score was -48% with AK002 and -22% with placebo (least-squares mean difference, -26 percentage points; 95% CI, -44 to -9; P = 0.004). Adverse events associated with AK002 were similar to those with placebo, with the exception of higher percentages of patients having mild-to-moderate infusion-related reactions with AK002 (60% in the combined AK002 group and 23% in the placebo group).

CONCLUSIONS

In patients with eosinophilic gastritis or duodenitis, AK002 reduced gastrointestinal eosinophils and symptoms. Infusion-related reactions were more common with AK002 than with placebo. (Funded by Allakos; ENIGMA ClinicalTrials.gov number, NCT03496571.).

Eosinophilic colitis in adults

Eosinophilic colitis (EoC) is a pathological entity associated with abnormal infiltration of colonic mucosa by eosinophilic polynuclear cells (Eo). This is a relatively common pathology in infants and children under 2 years old, but is more rare and has been less studied in adults. EoC can be classified as primary or secondary. Primary EoC is, in the majority of cases, related to an allergic reaction, either IgE-mediated and capable of causing an anaphylactic-type food allergy, or not mediated by IgE and capable of giving rise to food enteropathy. The symptoms for adults with EoC are variable and non-specific, diarrhoea and abdominal pain being the most common signs. There is no histological consensus for the diagnosis of EoC. The presence of over 40 Eo per high-power field (×400) in at least two different colonic segments could be suggested as the criterion for the diagnosis. In adults with primary EoC, skin tests are of limited value and the response to a restrictive diet is less effective than in young children, given that IgE or non-IgE-mediated allergic reactions are rarely identified and EoC generally require medical treatment. There is no consensus on the treatment of EoC, but the potential efficacy of corticosteroids and budesonide has been demonstrated in the vast majority of cases studied.

Biologics for the Treatment of Allergic Conditions: Eosinophil Disorders

Eosinophil-associated diseases are characterized by a common pathogenetic background, represented by eosinophil-led inflammation and overexpression of interleukin (IL)-5. IL-5 and its receptor are excellent therapeutic targets for eosinophil-associated diseases. Three monoclonal antibodies targeting IL-5 currently are available: mepolizumab and reslizumab block circulating IL-5 preventing the binding to its receptor, whereas benralizumab binds to IL-5 receptor α. They have a steroid-sparing effect in eosinophil disorders, such as eosinophilic granulomatosis with polyangiitis, hypereosinophilic syndrome, allergic bronchopulmonary aspergillosis, eosinophilic esophagitis, and chronic eosinophilic pneumonia. The biotechnological drugs targeting IL-5 are promising therapies; however, further studies are needed.

A Challenging Case of Recurrent Eosinophilic Peritonitis

Eosinophilic peritonitis is a rare presentation of eosinophilic gastroenteritis and is characterized by eosinophil-rich inflammation in any part of the gastrointestinal tract in the absence of secondary causes of eosinophilia. We report a case of a 48-year-old female who had recurrent hospital admissions due to abdominal pain and distension secondary to relapsing eosinophilic peritonitis.

Adrenal insufficiency is a contraindication for omalizumab therapy in mast cell activation disease: risk for serum sickness

Omalizumab is an effective therapeutic humanized murine IgE antibody in many cases of primary systemic mast cell activation disease (MCAD). The present study should enable the clinician to recognize when treatment of MCAD with omalizumab is contraindicated because of the potential risk of severe serum sickness and to report our successful therapeutic strategy for such adverse event (AE). Our clinical observations, a review of the literature including the event reports in the FDA AE Reporting System, the European Medicines Agency Eudra-Vigilance databases (preferred search terms: omalizumab, Xolair®, and serum sickness) and information from the manufacturer’s Novartis database were used. Omalizumab therapy may be more likely to cause serum sickness than previously thought. In patients with regular adrenal function, serum sickness can occur after 3 to 10 days which resolves after the antigen and circulating immune complexes are cleared. If the symptoms do not resolve within a week, injection of 20 to 40 mg of prednisolone on two consecutive days could be given. However, in MCAD patients whose adrenal cortical function is completely suppressed by exogenous glucocorticoid therapy, there is a high risk that serum sickness will be masked by the MCAD and evolve in a severe form with pronounced damage of organs and tissues, potentially leading to death. Therefore, before the application of the first omalizumab dose, it is important to ensure that the function of the adrenal cortex is not significantly limited so that any occurring type III allergy can be self-limiting.

Eosinophilic gastroenteritis with multiple serous membrane effusion as the first sign: a case report and literature review

Multiple serous membrane effusion (MSSE) as the first sign of eosinophilic gastroenteritis is extremely rare, and its clinical features and treatment methods have not been well described. The clinical characteristics, diagnosis, and treatment methods of MSSE in a 44-year-old woman were retrospectively reviewed. Laboratory testing revealed an elevated eosinophil count and serum immunoglobulin E level. The levels of all tumor markers were normal, but the CA125 level in serum and ascitic fluid was significantly increased. Ultrasonography showed a large amount of ascites and a moderate amount of pleural effusion. Echocardiography showed a small amount of pericardial effusion. Chest and abdominal computed tomography showed gastrointestinal wall thickening. Moreover, eosinophilic infiltration was detected in duodenal and rectal biopsy samples that had been collected during endoscopic examination of the upper gastrointestinal system. The patient was treated with 30 mg of prednisolone, and seafood was excluded from her diet for 4 weeks. The prednisolone was tapered over 8 weeks and continued at 5 mg prednisolone daily thereafter. The MSSE and peripheral eosinophilia showed a dramatic response to the steroid treatment. This case indicates that we should be highly aware of MSSE as the first clinical manifestation of eosinophilic gastroenteritis.

Eosinophilic Gastrointestinal Disorders

Eosinophilic gastrointestinal disorders (EGID) are a group of disorders characterized by pathologic eosinophilic infiltration of the esophagus, stomach, small intestine, or colon leading to organ dysfunction and clinical symptoms (J Pediatr Gastroenterol Nutr; Spergel et al., 52: 300-306, 2011). These disorders include eosinophilic esophagitis (EoE), eosinophilic gastritis (EG), eosinophilic gastroenteritis (EGE), eosinophilic enteritis (EE), and eosinophilic colitis (EC). Symptoms are dependent not only on the location (organ) as well as extent (layer invasion of the bowel wall). Common symptoms of EoE include dysphagia and food impaction in adults and heartburn, abdominal pain, and vomiting in children. Common symptoms of the other EGIDs include abdominal pain, nausea, vomiting, early satiety, diarrhea, and weight loss. These disorders are considered immune-mediated chronic inflammatory disorders with strong links to food allergen triggers. Treatment strategies focus on either medical or dietary therapy. These options include not only controlling symptoms and bowel inflammation but also on identifying potential food triggers. This chapter will focus on the clinical presentation, pathophysiology, and treatment of these increasingly recognized disorders.

Eosinophilic Gastrointestinal Diseases in Children: A Practical Review

Primary eosinophilic gastrointestinal diseases (EGIDs) represent a heterogeneous group of disorders characterized by eosinophilic inflammation in the absence of known causes for eosinophilia, selectively affecting different segments of the gastrointestinal tract. While pediatric eosinophilic esophagitis (EoE) is a well-defined disease with established guidelines, Eosinophilic Gastritis (EoG), Eosinophilic Gastroenteritis (EoGE) and Eosinophilic Colitis (EoC) remain a clinical enigma with evidence based on limited anecdotal case reports. Large cross-sectional studies in the US defined a prevalence of EoG and EoGE ranging from 1,5 to 6,4/100.000 and from 2,7 to 8,3/100.000 subjects respectively, while the prevalence of EoC ranges from 1,7 to 3,5/100.000 subjects. Regarding the pathogenesis, it is hypothesized that EGIDs result from the interplay between genetic predisposition, intestinal dysbiosis and environmental triggers. Clinically, EGIDs might present with different and nonspecific gastrointestinal symptoms depending on the involved intestinal tract and the extension of eosinophilic inflammatory infiltrate. The diagnosis of EGIDs requires: 1. recurrent gastrointestinal symptoms, 2. increased eosinophils for high power field in biopsy specimens, 3. absence of secondary causes of gastrointestinal eosinophilia. No validated guidelines are available on the clinical management of patients with EGIDs. Evidence from case reports and small uncontrolled case series suggests the use of dietary and corticosteroids as the first-line treatments. Considering the clinical follow-up of EGIDs, three different patterns of disease course are identified: single flare, recurring course-disease and chronic course-disease. This review will focus on pediatric EGIDs distal to esophagus, including Eosinophilic Gastritis (EoG), Eosinophilic Gastroenteritis (EoGE) and Eosinophilic Colitis (EoC).

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.

Signals from the various immune cells in promoting food allergy-induced eosinophilic esophagitis like disease

Eosinophilic esophagitis (EoE) is a recently recognized esophageal inflammatory disease with clinical manifestations arising from esophageal dysfunction. The etiology of EoE is currently being clarified and food allergy is evolving as the central cornerstone of EoE disease pathogenesis. Given the large number of eosinophils in the esophagus of people with EoE verified by data from murine models EoE is widely considered as the hallmark T-helper type 2 (Th2) disease of the esophagus. It is also known that some eosinophilic inflammation is controlled by other subsets of T cells such as Th9 or Th17 and control is also exerted by type 2 innate lymphoid cells acting together with basophils. In this paper we review results from molecular studies of mouse models in light of the results from the first clinical trials targeting key cytokines in humans and present in-depth molecular understanding of EoE.

Eosinophilic gastroenteritis: diagnosis and clinical perspectives

Eosinophilic gastroenteritis (EGE) is a digestive disorder in children and adults that is characterized by eosinophilic infiltration in the stomach and intestine. The underlying molecular mechanisms predisposing to this disease are unknown, but it seems that hypersensitivity response plays a major role in its pathogenesis, as many patients have a history of seasonal allergies, food sensitivities, asthma, and eczema. Symptoms and clinical presentations vary, depending on the site and layer of the gastrointestinal wall infiltrated by eosinophils. Laboratory results, radiological findings, and endoscopy can provide important diagnostic evidence for EGE; however, the cornerstone of the diagnosis remains the histological examination of gastric and duodenal specimens for evidence of eosinophilic infiltration (>20 eosinophils per high-power field), and finally clinicians make the diagnosis in correlation with and by exclusion of other disorders associated with eosinophilic infiltration. Although spontaneous remission is reported in around 30%–40% of EGE cases, most patients require ongoing treatment. The management options for this disorder include both dietary and pharmacological approaches, with corticosteroids being the mainstay of therapy and highly effective. The subsequent course is quite variable. Some patients have no recurrences, while a few experience recurrent symptoms during or immediately after corticosteroid interruption. An alternative therapeutic armamentarium includes mast-cell stabilizers, leukotriene antagonists, antihistamines, immunomodulators, and biological agents. In this review, we provide a summary of the different diagnostic tools utilized in practice, as well as the different therapeutic approaches available for EGE management.

Eosinophilic esophagitis-Where are we today?

OBJECTIVE

The objective of this review is to provide an overview of the practical diagnostic and therapeutic approaches to eosinophilic esophagitis and to increase the visibility of the disease among pediatricians.

SOURCES

A search of the MEDLINE, Embase, and CINAHL databases and recent consensus statements and guidelines were performed.

SUMMARY OF THE FINDINGS

The definition of eosinophilic esophagitis is based on symptoms and histology. It is important to rule out other diseases associated with esophageal eosinophil-predominant inflammation. It is not yet clear whether the increased prevalence is due to a real increase in incidence or a result of increased awareness of the disease. Various options for management have been used in pediatric patients, including proton pump inhibitors, dietary restriction therapies, swallowed topical steroids, and endoscopic dilations. More recently, proton pump inhibitor-responsive esophageal eosinophilia and eosinophilic esophagitis have been contemplated on the same spectrum, and proton pump inhibitors should be considered the initial step in the treatment of these patients.

CONCLUSIONS

Eosinophilic esophagitis is a relatively new disease with a remarkable progression of its incidence and prevalence in the past two to three decades, and diagnostic criteria that are constantly evolving. It is important to better understand the pathogenesis of the disease, the predisposing factors, the natural history, and the categorization of varying phenotypes to develop diagnostic and therapeutic strategies that meet the clinical needs of patients.

A review on methodologies for extraction, identification and quantification of allergenic proteins in prawns

Prawn allergy is one of the most common food-borne allergies and current prevention is by avoidance. This review paper summarised different methodologies for the extraction, identification and quantification of prawn protein allergens, reported in various research studies. Following extraction, allergenic components have been analysed using well-established methodologies, such as SDS-PAGE, Immunoblotting, ELISA, CD Spectroscopy, HPLC, DBPCFC, SPT etc. Moreover, the preference towards Aptamer-based technique for allergenicity analysis has also been highlighted in this review paper. The summary of these methodologies will provide a reference platform for present and future research directions.