Proton Pump Inhibitor Therapy for Eosinophilic Esophagitis: History, Mechanisms, Efficacy, and Future Directions

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.

Diagnosis, management and therapeutic options for eosinophilic esophagitis

PURPOSE OF REVIEW

Eosinophilic esophagitis is a chronic and commonly evolving condition leading to relevant and potentially irreversible burden in terms of tissue damage and related functional impairment, thus significantly impacting on quality of life. The aim of the present review is to summarize the recent advances in terms of diagnostic work-up and pharmacological and nonpharmacological management of the disease, under the broader perspective of type 2 inflammation.

RECENT FINDINGS

Two major novelties have prompted an innovative approach to EoE. In terms of diagnosis, it has been proposed to dissect the disease heterogeneity in three endotypes, independent from tissue eosinophil number: EoEe1, characterized by normal appearing oesophagus; EoEe2, associated with type 2 inflammation and steroid-refractoriness; EoEe3, whose features include adult onset, a more fibro-stenotic aspect and loss of epithelial gene expression. Concerning treatment, two recently licensed drugs for EoE, oro-dispersible budesonide and dupilumab represent the first treatment options specifically developed for EoE and addressing EoE-related peculiar pathobiological features.

SUMMARY

In the era of precision medicine, managing EoE according to a phenotype-driven approach might be helpful in defining the best treatment options in the different disease forms or stages. In addition, exploring the coexistence or the previous occurrence of other type 2 conditions may suggest the opportunity to specifically target type 2 inflammation through biologic therapy. The complex EoE pathobiology combining inflammatory and functional features, both at organ and systemic level, requires a multidimensional approach relying on the strict integration of gastroenterologists and allergist-immunologists.

Potassium-competitive acid blockers and acid-related disorders

PURPOSE OF REVIEW

Potassium-competitive acid blockers (PCABs) represent a new class of compounds for the treatment of acid-related disorders. Recent FDA approval of the PCAB vonoprazan for erosive esophagitis has started an important new approach to acid-related disorders.

RECENT FINDINGS

Compared to conventional proton pump inhibitors (PPIs), PCABs provide more rapid, potent, and sustained suppression of gastric acid with faster and more durable symptom relief. Studies have demonstrated the efficacy of PCABs for erosive esophagitis, nonerosive reflux disease, and peptic ulcer disease including H. pylori. However, the PCAB vonoprazan was only approved in the US as part of combination therapy for eradication of H. pylori. Clinical trials have now demonstrated noninferiority of vonoprazan to lansoprazole for treatment of erosive esophagitis, particularly noting superiority of vonoprazan in patients with severe esophagitis resulting in FDA approval of vonoprazan for treatment of erosive esophagitis. Emerging data suggests a possible utility of vonoprazan for PPI-resistant gastroesophageal reflux disease (GERD) and on-demand therapy for nonerosive reflux disease. Vonoprazan is generally well tolerated but long-term safety data is not well established.

SUMMARY

The PCAB vonoprazan is a newly FDA approved treatment option for erosive esophagitis. Its possible role in PPI-resistant GERD and nonerosive reflux disease warrants further investigation.

Associations of Eosinophilic Gastrointestinal Disorders with Other Gastrointestinal and Allergic Diseases

Eosinophilic gastrointestinal disorders (EGIDs) are becoming more common causing significant suffering and reduced quality of life. These conditions can affect different parts of the digestive system, either individually or in combination. Recognition of their link to allergic disorders or other gastrointestinal (GI) diseases has raised questions about their shared underlying mechanisms, which has had implications for diagnosis and management. The authors critically examine the current understanding of the connection between EGIDs and allergic conditions (ie, atopic dermatitis, allergic rhinitis, asthma, and food allergy) and GI diseases (ie, inflammatory bowel disease, celiac disease, gastroesophageal reflux disease, and motility disorders).

High prevalence of response to PPI treatment in children and adolescents with eosinophilic esophagitis in southern Brazil

Introduction

Eosinophilic esophagitis is a newly recognized entity, in which there is significant evidence available that clearly demonstrates the positive impact of PPIs on reducing esophageal eosinophilia in individuals across different age groups, including children, adolescents, and adults. Multiple mechanisms have been proposed to explain how this treatment effect occurs. In Brazil, there seems to be a lack of studies that have prospectively assessed the clinical and therapeutic response rate in pediatric patients with EoE. The objective of this study was to prospectively evaluate the clinical and therapeutic response of pediatric patients with EoE in a medical center located in southern Brazil, by investigating the effectiveness of PPI treatment.

Methods

This study is a clinical, prospective, open trial that took place in a pediatric hospital located in southern Brazil. The focus of the study was on patients diagnosed with Eosinophilic Esophagitis (EoE) who were given treatment using omeprazole/esomeprazole at a dosage of 1 mg.kg per dose, twice daily, for a period of 8-12 weeks. Following the treatment period, the patients underwent another endoscopy. Patients who exhibited 15 or less eosinophils in the biopsy conducted after the treatment were considered as responders.

Results

A total of 27 patients was evaluated (74.1% boys). The average age (± standard deviation) was 8 years (±4). Nineteen patients (70.3%) were considered as responders to PPI treatment: 6 patients-22.2%-exhibited a complete response (defined as having 5 or fewer eosinophil per high power field. Additionally, 13 patients-48.1%-demonstrated a partial response, characterized by eosinophil counts exceeding 5 but less than 15 eos/hpf. When comparing the responder and non-responder groups at presentation, a statistical difference was observed in the prevalence of food refusal as a presenting symptom. Food refusal was found to be more prevalent in the non-responder group (87.5% vs. 26.3%, P = 0.008). No differences were observed in terms of atopy history and endoscopic scores. Upon comparing the histological findings from the post-treatment endoscopy of the two groups, it was observed that PPI responders exhibited a greater tendency to decrease basal cell hyperplasia (P = 0.06) and intercellular edema (P = 0.08).

Conclusion

In this group of pediatric patients with EoE in Southern Brazil most patients showed a high prevalence of histological, endoscopic, and clinical response to PPI treatment. PPIs showed efficacy in Brazilian patients with EoE, most of whom would probably not be able to adequately undergo other treatments.

Clinical Trial Registration

https://ensaiosclinicos.gov.br/rg/RBR-2ntbth9, identifier (U1111-1301-1842).

Responses of Proton Pump Inhibitors and Potassium-Competitive Acid Blockers According to Outcomes of Symptom, Endoscopy, and Histology in Patients With Eosinophilic Esophagitis

GOALS

We aimed to examine the response rate to proton pump inhibitors (PPIs) and potassium-competitive acid blockers and the prevalence of topical corticosteroid (TCS) therapy as the second-line treatment for eosinophilic esophagitis (EoE).

BACKGROUND

Acid-suppressive drugs such as PPIs and potassium-competitive acid blockers are often used to treat EoE. Treatment response is based on outcomes including symptoms, endoscopy, and histology; however, the detailed response rate to PPI/P-CAB is unknown.

STUDY

In total, 236 patients with histologically confirmed EoE who received PPI/P-CAB as the first-line treatment were included. We assessed the symptoms, endoscopic reference score (EREFS), and histology [eosinophils per high-power field (eos/hpf)] 8 weeks after PPI/P-CAB administration. Complete normalization was defined as the disappearance of symptoms, EREFS score 0, or 0-1 eos/hpf, and response as disappearance or improvement of symptoms, EREFS score ≤2, or <15 eos/hpf. The prevalence of TCS therapy in each response group was assessed.

RESULTS

Complete normalization was achieved in 25%, 50%, 36%, and 8% of patients for symptoms, endoscopy, histology, and all 3 outcomes, respectively. The response rates were 81%, 87%, 87%, 75%, and 60% for symptoms, endoscopy, histology, and all 3 outcomes, respectively. TCS use was significantly lower (8%) in patients who achieved response of all 3 outcomes than in other groups and was dependent on the number of outcomes with nonresponse.

CONCLUSIONS

Complete normalization of symptoms, endoscopy, and histology using PPI/P-CAB is uncommon. Based on treatment efficacy by response/nonresponse, TCS was the secondary treatment in cases with an increase in the number of nonresponse outcomes.

Impact of STAT6 Variants on the Response to Proton Pump Inhibitors and Comorbidities in Patients with Eosinophilic Esophagitis

Proton pump inhibitors (PPIs) are the first-line drug for eosinophilic esophagitis (EoE), although it is estimated that there is a lack of histological remission in 50% of patients. This research aimed to identify pharmacogenetic biomarkers predictive of PPI effectiveness and to study their association with disease features. Peak eosinophil count (PEC) and the endoscopic reference score (EREFS) were determined before and after an eight-week PPI course in 28 EoE patients. The impact of the signal transducer and activator of transcription 6 (STAT6), CYP2C19, CYP3A4, CYP3A5, and ABCB1 genetic variations on baseline PEC and EREFS, their reduction and histological response, and on EoE symptoms and comorbidities was analyzed. PEC reduction was higher in omeprazole-treated patients (92.5%) compared to other PPIs (57.9%, p = 0.003). STAT6 rs12368672 (g.18453G>C) G/G genotype showed higher baseline PEC values compared to G/C and C/C genotypes (83.2 vs. 52.9, p = 0.027). EREFS reduction in STAT6 rs12368672 G/G and G/C genotypes was higher than in the C/C genotype (36.7% vs. -75.0% p = 0.011). However, significance was lost after Bonferroni correction. Heartburn incidence was higher in STAT6 rs167769 (g.27148G>A) G/G patients compared to G/A (54.55% vs. 11.77%, p = 0.030). STAT6 rs12368672G>C and rs167769G>A variants might have a relevant impact on EoE status and PPI response. Further research is warranted to clarify the clinical relevance of these variants.

ACCURACY OF THE EOSINOPHILIC ESOPHAGITIS ENDOSCOPIC REFERENCE SCORE IN CHILDREN

BACKGROUND

To assess the efficacy of applying the endoscopic reference score for EoE (EREFS) in children with symptoms of esophageal dysfunction naïve to proton pump inhibitor (PPI) therapy.

METHODS

An observational cross-sectional study was conducted by reviewing reports and photographs of upper gastrointestinal endoscopies (UGE) and esophageal biopsies of patients with symptoms of esophageal dysfunction. Patients who were treated with PPI or had other conditions that may cause esophageal eosinophilia were excluded.

RESULTS

Of the 2,036 patients evaluated, endoscopic findings of EoE were identified in 248 (12.2%) and more than one abnormality was observed in 167 (8.2%). Among all patients, 154 (7.6%) presented esophageal eosinophilia (≥15 eosinophils per high power field) (P<0.01). In this group, 30 patients (19.5%) had normal endoscopy. In patients with EoE, edema (74% vs 6.5%, P<0.01) and furrows (66.2% vs 2.4%, P<0.01) were more prevalent than in the control group. Association of edema and furrows was more frequent in patients with EoE than in the control group (29.2% vs 1.6%, P<0.01, OR=24.7, CI=15.0-40.5). The presence of more than one endoscopic finding had sensitivity of 80.5%, specificity of 93.4%, positive predictive value (PPV) of 50%, negative predictive value (NPV) of 98.3%, and accuracy of 92.4%.

CONCLUSION

In conclusion, this study showed that endoscopic features suggestive of EoE had high specificity and NPV for diagnosing EoE in children naïve to PPI therapy. These findings highlight the importance of the EREFS in contributing to early identification of inflammatory and fibrostenosing characteristics of EoE, making it possible to identify and to avoid progression of the disease.

BACKGROUND

• The EoE endoscopic reference score (EREFS) was developed and validated in adults and has been demonstrated to be an adequate tool for diagnosing and assessing treatment response in children.

BACKGROUND

• The presence of more than one endoscopic finding stronglysuggests EoE.

BACKGROUND

• The EoE endoscopic reference score presents high specificity and negative predictive value for diagnosing EoE in children naïve to proton pump inhibitor (PPI) therapy.

BACKGROUND

• Endoscopic findings suggestive of EoE in patients naïve to treatment may be useful to characterize disease phenotype and individualize treatment according to the initial clinical presentation.

Eosinophilic esophagitis: does age matter?

INTRODUCTION

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease of the esophagus with increasing prevalence worldwide. It is a multifactorial disease caused by a combination of immunologic, genetic, and environmental factors. The clinical presentation of EoE varies largely, especially between different age groups. While diagnostic criteria and therapeutic goals are similar in children and adults, there are differences in treatment, with a more cautious approach in children to avoid growth disturbances. In addition, close monitoring and follow-up are essential in children to ensure uninterrupted growth.

AREAS COVERED

A search in PubMed/MEDLINE, EMBASE, and SCOPUS databases was conducted to identify relevant studies published between January 2010 and January 2023 to give an overview of the state-of-the-art of EoE epidemiology, diagnosis, and treatment while focusing on similarities and differences between the adult and the pediatric population.

EXPERT OPINION

The current state of research indicates that while significant progress has been made in understanding and treating EoE, further research and advances are needed to optimize diagnostic strategies, tailored treatment approaches, monitoring, and follow-up, and improve long-term outcomes for patients. With further innovation, the management of EoE can become more precise and tailored, leading to better patient outcomes and improved quality of life.

The Usefulness of the Eosinophilic Esophagitis Histology Scoring System in Predicting Response to Proton Pump Inhibitor Monotherapy in Children with Eosinophilic Esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is an immune-mediated esophageal disease with rising incidence. While proton pump inhibitors (PPIs) are the first-line treatment, a significant proportion of patients do not respond. This study aimed to determine if the EoE Histology Scoring System (EoEHSS) can predict PPI responsiveness.

METHODS

A cross-sectional study was conducted on 89 pediatric patients diagnosed with EoE between 2016 and 2022. Patients were categorized into PPI responders (PPIREoE) and non-responders (PPINREoE) based on post-treatment biopsies. EoEHSS values from biopsies of the esophagus (distal, middle, and proximal segments) were compared between the two groups.

RESULTS

No significant differences in EoEHSS scores were observed for the distal and proximal esophagus between the groups. However, the middle esophagus showed a significantly higher EoEHSS grade score in the PPINREoE group, indicating a more pronounced disease severity. Specific histological features, particularly eosinophilic abscesses and surface layering of the middle segment of the esophagus, were significantly different between the groups.

CONCLUSIONS

Performing a biopsy of each esophageal segment, particularly the middle, is crucial for diagnostic precision and predicting PPI responsiveness. The EoEHSS can serve as a valuable tool in predicting therapy response, emphasizing the need for personalized therapeutic approaches in EoE management.

Treatment of Pediatric Eosinophilic Esophagitis: Traditional and Novel Therapies

PURPOSE OF REVIEW

This review presents and summarizes the existing studies on the treatment goals and options for pediatric eosinophilic esophagitis utilizing rigorous peer-reviewed literature.

RECENT FINDINGS

In addition to traditional treatments, emerging biologic therapies continue to evolve the approach to treating pediatric eosinophilic esophagitis. Well defined treatment goals will aid the continued development of new therapies. Further, innovative assessment tools have changed how the clinician is able to assess the effectiveness of therapies with a trend toward less invasive options. The management of pediatric eosinophilic esophagitis continues to evolve with the advent of both novel treatment options and assessment tools. Treatment choices, with benefits and risks involved, should be presented to families upon diagnosis and tailored towards the individual patient and likelihood of adherence and success. Biologic therapy for EoE presents an exciting option for both first line therapy and escalation for those with severe or unresponsive disease.

Mechanistic Insights into Eosinophilic Esophagitis: Therapies Targeting Pathophysiological Mechanisms

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease characterized by eosinophilic infiltration of the esophagus. It arises from a complex interplay of genetic predisposition (susceptibility loci), environmental triggers (allergens and dietary antigens), and a dysregulated immune response, mainly mediated by type 2 T helper cell (Th2)-released cytokines, such as interleukin (IL)-4, IL-5, and IL-13. These cytokines control eosinophil recruitment and activation as well as tissue remodeling, contributing to the characteristic features of EoE. The pathogenesis of EoE includes epithelial barrier dysfunction, mast cell activation, eosinophil degranulation, and fibrosis. Epithelial barrier dysfunction allows allergen penetration and promotes immune cell infiltration, thereby perpetuating the inflammatory response. Mast cells release proinflammatory mediators and promote eosinophil recruitment and the release of cytotoxic proteins and cytokines, causing tissue damage and remodeling. Prolonged inflammation can lead to fibrosis, resulting in long-term complications such as strictures and dysmotility. Current treatment options for EoE are limited and mainly focus on dietary changes, proton-pump inhibitors, and topical corticosteroids. Novel therapies targeting key inflammatory pathways, such as monoclonal antibodies against IL-4, IL-5, and IL-13, are emerging in clinical trials. A deeper understanding of the complex pathogenetic mechanisms behind EoE will contribute to the development of more effective and personalized therapeutic strategies.

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.

Medical treatment of eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is a chronic antigen-mediated eosinophilic inflammatory disease isolated to the esophagus. As a clinicopathologic disorder, a diagnosis of EoE requires a constellation of clinical symptoms of esophageal dysfunction and histologic findings (at least 15 eosinophils/high-powered microscope field (eos/hpf)). Current guidelines no longer require the failure of response to proton pump inhibitor medications to establish a diagnosis of EoE, but continue to suggest the exclusion of other etiologies of esophageal eosinophilia. The treatment goals for EoE are improvement in clinical symptoms, resolution of esophageal eosinophilia and other histologic abnormalities, endoscopic improvement, improved quality of life, improved esophageal function, minimized adverse effects of treatment, and prevention of disease progression and subsequent complications. Currently, there is no cure for EoE, making long-term treatment necessary. Standard treatment modalities include dietary modifications, esophageal dilation, and pharmacologic therapy. Effective pharmacologic therapies include corticosteroids, rapidly emerging biological therapies, and proton pump inhibitor medications.

OBJECTIVES

To evaluate the efficacy and safety of medical interventions for people with eosinophilic esophagitis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, ClinicalTrials.gov, and WHO ICTRP to 3 March 2023.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing any medical intervention or food elimination diet for the treatment of eosinophilic esophagitis, either alone or in combination, to any other intervention (including placebo).

DATA COLLECTION AND ANALYSIS

Pairs of review authors independently selected studies and conducted data extraction and risk of bias assessment. We expressed outcomes as a risk ratio (RR) and as the mean or standardized mean difference (MD/SMD) with 95% confidence interval (CI). We assessed the certainty of the evidence using GRADE. Our primary outcomes were: clinical, histological, and endoscopic improvement, and withdrawals due to adverse events. Secondary outcomes were: serious and total adverse events, and quality of life.

MAIN RESULTS

We included 41 RCTs with 3253 participants. Eleven studies included pediatric patients while the rest recruited both children and adults. Four studies were in patients with inactive disease while the rest were in patients with active disease. We identified 19 intervention comparisons. In this abstract we present the results of the primary outcomes for the two main comparisons: corticosteroids versus placebo and biologics versus placebo, based on the prespecified outcomes defined of the primary studies. Fourteen studies compared corticosteroids to placebo for induction of remission and the risk of bias for these studies was mostly low. Corticosteroids may lead to slightly better clinical improvement (20% higher), measured dichotomously (risk ratio (RR) 1.74, 95% CI 1.08 to 2.80; 6 studies, 583 participants; number needed to treat for an additional beneficial outcome (NNTB) = 4; low certainty), and may lead to slightly better clinical improvement, measured continuously (standard mean difference (SMD) 0.51, 95% CI 0.17 to 0.85; 5 studies, 475 participants; low certainty). Corticosteroids lead to a large histological improvement (63% higher), measured dichotomously (RR 11.94, 95% CI 6.56 to 21.75; 12 studies, 978 participants; NNTB = 3; high certainty), and may lead to histological improvement, measured continuously (SMD 1.42, 95% CI 1.02 to 1.82; 5 studies, 449 participants; low certainty). Corticosteroids may lead to little to no endoscopic improvement, measured dichotomously (RR 2.60, 95% CI 0.82 to 8.19; 5 studies, 596 participants; low certainty), and may lead to endoscopic improvement, measured continuously (SMD 1.33, 95% CI 0.59 to 2.08; 5 studies, 596 participants; low certainty). Corticosteroids may lead to slightly fewer withdrawals due to adverse events (RR 0.64, 95% CI 0.43 to 0.96; 14 studies, 1032 participants; low certainty). Nine studies compared biologics to placebo for induction of remission. Biologics may result in little to no difference in clinical improvement, measured dichotomously (RR 1.14, 95% CI 0.85 to 1.52; 5 studies, 410 participants; low certainty), and may result in better clinical improvement, measured continuously (SMD 0.50, 95% CI 0.22 to 0.78; 7 studies, 387 participants; moderate certainty). Biologics result in better histological improvement (55% higher), measured dichotomously (RR 6.73, 95% CI 2.58 to 17.52; 8 studies, 925 participants; NNTB = 2; moderate certainty). We could not draw conclusions for this outcome when measured continuously (SMD 1.01, 95% CI 0.36 to 1.66; 6 studies, 370 participants; very low certainty). Biologics may result in little to no difference in endoscopic improvement, measured dichotomously (effect not estimable, low certainty). We cannot draw conclusions for this outcome when measured continuously (SMD 2.79, 95% CI 0.36 to 5.22; 1 study, 11 participants; very low certainty). There may be no difference in withdrawals due to adverse events (RR 1.55, 95% CI 0.88 to 2.74; 8 studies, 792 participants; low certainty).

AUTHORS' CONCLUSIONS

Corticosteroids (as compared to placebo) may lead to clinical symptom improvement when reported both as dichotomous and continuous outcomes, from the primary study definitions. Corticosteroids lead to a large increase in histological improvement (dichotomous outcome) and may increase histological improvement (continuous outcome) when compared to placebo. Corticosteroids may or may not increase endoscopic improvement (depending on whether the outcome is measured dichotomously or continuously). Withdrawals due to adverse events (dichotomous outcome) may occur less frequently when corticosteroids are compared to placebo. Biologics (as compared to placebo) may not lead to clinical symptom improvement when reported as a dichotomous outcome and may lead to an increase in clinical symptom improvement (as a continuous outcome), from the primary study definitions. Biologics lead to a large increase in histological improvement when reported as a dichotomous outcome, but this is uncertain when reported as a continuous outcome, as compared to placebo. Biologics may not increase endoscopic improvement (dichotomous outcome), but this is uncertain when measured as a continuous outcome. Withdrawals due to adverse events as a dichotomous outcome may occur as frequently when biologics are compared to placebo.

Novel corticosteroid formulations in the treatment of eosinophilic esophagitis: what is the evidence?

Background and study aims

Eosinophilic esophagitis (EoE) is a food allergen-induced disease of the esophagus. Chronic, eosinophil-predominant inflammation eventually leads to fibrosis, esophageal dysfunction and severe morbidity. Swallowed topical corticosteroids (STCs) are a mainstay of anti-inflammatory therapy in the treatment of active EoE. Data on the efficacy of novel corticosteroid formulations, developed specifically for esophageal delivery, have recently become available.

Methods

A comprehensive review was performed aiming to summarize evidence on the role of STCs in the treatment of EoE. Two biomedical bibliographic databases (PubMED, EMBASE) were searched for articles providing original information on the efficacy and safety of STCs in adult EoE patients.

Results

Budesonide orodispersible tablet (BOT) and budesonide oral suspension (BOS) both surpassed placebo formulations regarding the efficacy of inducing and maintaining histologic, symptomatic and endoscopic remission. Overall, BOT displayed the highest grade of efficacy with clinico-histologic remission rates up to 75% after 1 year. Fluticasone propionate (APT-1011) achieved and maintained histologic and endoscopic responses in the majority of patients, whereas only a positive trend was demonstrated for symptomatic improvement. Mometasone and ciclesonide were studied in a limited number of smaller-scale trials and placebo-controlled data are required to substantiate the promising findings. All STCs displayed a similar side effects profile and were generally considered safe and well-tolerated.

Conclusions

Current evidence supports long-term treatment with novel corticosteroid formulations, challenging the established treatment paradigm of EoE. BOT appears to be the most effective steroid therapy, although head-to-head comparative trials between STCs are needed.

Food allergy: cause or consequence of pediatric eosinophilic esophagitis? Potential implications of ultraprocessed foods in prevention and management

Eosinophilic esophagitis (EoE) is a chronic, immune-mediated disease characterized by eosinophilic infiltration, leading to esophageal dysfunction, inflammation, and fibrotic remodeling. In the last few decades, there has been an increased prevalence of EoE at an alarming rate in the pediatric age. The pathogenesis of EoE is still largely undefined, and this limits the definition of effective strategies for the prevention and management of this condition. EoE is considered a multifactorial disease arising from a negative interaction between environmental factors and genetic background, causing an impaired esophageal epithelial barrier with subsequent abnormal allergen exposure activating type 2 (Th2) inflammation. Food antigens have been suggested as key players in Th2 inflammation in pediatric patients with EoE, but emerging evidence suggests a potential role of other dietary factors, including ultraprocessed foods, as possible triggers for the occurrence of EoE. In this paper, we discuss the potential role of these dietary factors in the development of the disease, and we propose a new approach for the management of pediatric patients with EoE.

Paediatric gastrointestinal endoscopy in the Asian-Pacific region: Recent advances in diagnostic and therapeutic techniques

There has been a rapid expansion in the knowledge of paediatric gastroenterology over the recent decade, with a fast-growing repertoire of diagnostic techniques and management strategies for a wide spectrum of childhood gastrointestinal (GI) diseases. Paediatric GI endoscopy is a core competency every paediatric gastroenterologist should possess, and represents one of the most common procedures performed in children for both diagnostic and therapeutic purposes. Yet there remains a dearth of literature on the utility and outcomes of paediatric GI endoscopy in the Asia-Pacific region. Data on the diagnostic value of paediatric GI endoscopy would be an important aspect of discussion, with the emergence of inflammatory bowel disease (IBD) and eosinophilic GI disease as increasingly common endoscopic diagnoses. Time-based trends in paediatric GI endoscopy do point towards more IBD and gastroesophageal reflux disease-related complications being diagnosed, with a declining incidence of GI bleeding. However, the real-world diagnostic value of endoscopy in Asia must be contextualised to the region-specific prevalence of paediatric GI diseases. Helicobacter pylori infection, particularly that of multidrug-resistant strains, remains a highly prevalent problem in specific regions. Paediatric functional GI disorders still account for the majority of childhood GI complaints in most centres, hence the diagnostic yield of endoscopy should be critically evaluated in the absence of alarm symptoms. GI therapeutic endoscopy is also occasionally required for children with ingested foreign bodies, intestinal polyposis or oesophageal strictures requiring dilation. Endoscopic haemostasis is a potentially life-saving skill in cases of massive GI bleeding typically from varices or peptic ulcers. Advanced endoscopic techniques such as capsule endoscopy and balloon-assisted enteroscopy have found traction, particularly in East Asian centres, as invaluable diagnostic and therapeutic tools in the management of IBD, obscure GI bleeding and intestinal polyposis. State of the art endoscopic diagnostics and therapeutics, including the use of artificial intelligence-aided endoscopy algorithms, real-time confocal laser endomicroscopy and peroral endoscopic myotomy, are expected to gain more utility in paediatrics. As paediatric gastroenterology matures as a subspecialty in Asia, it is essential current paediatric endoscopists and future trainees adhere to minimum practice standards, and keep abreast of the evolving trends in the diagnostic and therapeutic value of endoscopy. This review discusses the available published literature on the utility of paediatric GI endoscopy in Asia Pacific, with the relevant clinical outcomes.

Genetic and Molecular Contributors in Eosinophilic Esophagitis

PURPOSE OF REVIEW

Eosinophilic esophagitis (EoE) is an allergic inflammatory esophageal disorder with a complex underlying genetic and molecular etiology. The interest of the scientific community in EoE has grown considerably over the past three decades, and the understanding of the genetic and molecular mechanisms involved in this disease has greatly increased.

RECENT FINDINGS

In this article, we aim to provide both historic aspects and updates on the recent genetic and molecular advances in the understanding of EoE. Although EoE is a relatively newly described disorder, much progress has been made toward identifying the genetic and molecular factors contributing to the disease pathogenesis by a variety of approaches with next-generation sequencing technologies, including genome-wide association study, whole exome sequencing, and bulk and single-cell RNA sequencing. This review highlights the multifaceted impacts of various findings that have shaped the current molecular and genetic landscape of EoE, providing insights that facilitate further understanding of the disease process.

Food elimination diet is a viable alternative therapy for eosinophilic esophagitis responsive to proton pump inhibitors

BACKGROUND

First-line treatment of eosinophilic esophagitis (EoE) includes monotherapy with proton-pump inhibitors (PPIs), food elimination diet (FED), or topical corticosteroids. Current guidelines suggest patients with EoE should continue any responsive first-line monotherapies. However, the efficacy of FED monotherapy in patients with EoE responsive to PPI monotherapy has not been well studied. Our study aimed to investigate how attempting FED monotherapy after experiencing remission of EoE after PPI monotherapy influenced long-term EoE management.

METHODS

We retrospectively identified patients with EoE responsive to PPI monotherapy who trialed FED monotherapy. We then employed a mixed method approach to a prospective cohort. Selected patients were observed long term for quantitative outcomes, while qualitative results were obtained from patient surveys regarding their perspectives on the trial of FED monotherapy.

RESULTS

We identified 22 patients who trialed FED monotherapy after experiencing remission of EoE following PPI monotherapy. Of these 22 patients, 13 had remission of EoE with FED monotherapy, while 9 had re-activation of EoE. Out of 22 patients, 15 were enrolled in a cohort for observation. No exacerbations of EoE occurred while on maintenance treatment. Most patients stated that they would recommend this process to others with EoE (93.33%) and that trial of FED monotherapy helped them identify a treatment plan that aligned with their lifestyle (80%).

CONCLUSION

Our work shows that FED monotherapy can be an effective alternative for patients with EoE responsive to PPI monotherapy that may improve patient quality of life, suggesting alternative treatment options should be considered for monotherapy-responsive EoE.

Proton Pump Inhibitor Therapy in Pediatric Eosinophilic Esophagitis: Predictive Factors and Long-Term Step-Down Efficacy

OBJECTIVES

To assess the short- and long-term efficacy of proton pump inhibitor (PPI) therapy for pediatric eosinophilic esophagitis (EoE) in real-world practice with a step-down strategy, and to evaluate factors predictive of PPI responsiveness.

METHODS

We collected data regarding the efficacy of PPIs during this cross-sectional analysis of the prospective nationwide RENESE registry. Children with EoE treated with PPI monotherapy were included. Histological remission was defined as a peak eosinophilic count of <15 eosinophils (eos)/high-power field (hpf). Factors associated with PPI responsiveness were identified using multivariate logistic regression analysis.

RESULTS

After induction therapy, histological and clinico-histological remission were observed in 51.4% (n = 346) and 46.5% of children, respectively. Normal endoscopic appearance of the esophagus was associated with a higher possibility [odds ratio (OR), 9.20; 95% confidence interval (CI), 2.10-40.16], and fibrostenotic phenotype was associated with a lower possibility (OR, 0.36; 95% CI, 0.18-0.74) of histological remission. Long-term therapy with a step-down strategy effectively maintained histological remission in 68.5% and 85.3% of children at 7 months (n = 108) and 16 months (n = 34), respectively. Complete initial histological remission (≤5 eos/hpf) was associated with a higher possibility of sustained histological remission (OR, 5.08; 95% CI, 1.75-14.68). Adverse events were infrequent and mild.

CONCLUSIONS

We confirmed the efficacy of PPIs for a large cohort of children with EoE with sustained histological remission using a step-down strategy. Children with fibrostenotic phenotypes are less likely to respond to induction therapy. Furthermore, patients with complete initial histological remission are more likely to experience long-term histological remission.

The Role of Pediatric Gastroenterologists in the Evaluation of Complex Aerodigestive Disorders

PURPOSE OF REVIEW

Children with aerodigestive disorders frequently have concerns regarding difficulty breathing, swallowing, and growing. In this review, we explored the role of pediatric gastroenterologists in the evaluation of complex aerodigestive disorders and the overall approach to these often-challenging patients.

RECENT FINDINGS

Pediatric gastroenterologists evaluate children with aerodigestive concerns ranging from dysphagia and gastroesophageal reflux to complex congenital abnormalities such as esophageal atresia. Diagnostic tools, such as multichannel intraluminal impedance-pH monitoring, are used for diagnosing gastroesophageal reflux and assessing the correlation with symptoms. Endoscopic evaluation, and in some complex cases, with therapeutic dilations may also be performed. Gastrointestinal dysmotility evaluation with manometry studies are also being increasingly utilized. Multidisciplinary aerodigestive programs can provide a coordinated approach to children with complex airway, pulmonary and gastrointestinal tract disorders. A pediatric gastroenterologist's expertise and specialized skills not only offer many diagnostic tools for these complicated medical cases but are also important in long term medical management.

Proton Pump Inhibitors in Allergy: Benefits and Risks

Proton pump inhibitors (PPIs) are widely prescribed and are indicated for the treatment of several gastrointestinal disorders. Allergists may prescribe PPIs as a result of the coincidence of gastroesophageal reflux disease with asthma or rhinitis, or when gastroesophageal reflux disease presents as chronic cough. Furthermore, long-term, high-dose PPI therapy is a recommended option for managing eosinophilic esophagitis, resulting in histologic remission in approximately 40% of patients. Here, we discuss current recommendations for PPI use, its deescalation, and its side effect profile. We review evidence supporting the epidemiologic link between the use of acid-suppressant medication and the subsequent development of allergic disorders.

Pediatric eosinophilic esophagitis outcomes vary with co-morbid eczema and pollen food syndrome

Background

Eosinophilic esophagitis (EoE) is a chronic immune-mediated inflammatory disease characterized by eosinophil inflammation of the esophagus. It has been described as a component of the Allergic March and is often seen with other atopic diseases. Some atopic diseases, including asthma, are known to be heterogenous with endotypes that guide treatment. Similarly, we propose that EoE is a heterogenous disease with varying phenotypes and endotypes that might impact response to therapy.

Methods

A single-center retrospective review of pediatric patients ≤18 years of age diagnosed with EoE was conducted. All gastrointestinal clinic visits and esophagogastroduodenoscopies (EGD) from disease presentation through the first three years after diagnosis were reviewed. Histologic remission rate and therapies utilized [proton pump inhibitor (PPI), topical steroid, dietary elimination] were assessed.

Results

One hundred and thirty-seven patients were included, 80% of whom had at least one concurrent atopic condition at diagnosis, with food allergies being the most common (57%) followed by eczema (34%), and asthma (29%). The remission rate of the overall cohort was 65%, and by concurrent allergy, comorbid pollen food syndrome and eczema had the highest remission rates at 100% and 81%, respectively followed by asthma (62%), food allergies (62%), seasonal allergic rhinitis (60%), and history of anaphylaxis (56%). Kaplan-Meier curves for each atopic condition show that patients with eczema and pollen food syndrome achieve histologic remission faster than those without. All treatment modalities were more successful in patients with eczema than those without, and PPI was most effective treatment at inducing remission.

Conclusions

In a real-world pediatric cohort, 80% of patients with EoE had an underlying atopic condition. Patients with eczema and pollen food syndrome had a swifter response and were more likely to achieve histologic remission than patients with other atopic conditions. This study suggests that EoE, like other allergic diseases, may have heterogenous phenotypes that could affect response to treatment. There is currently a knowledge gap in classifying EoE based on endotypes and phenotypes at diagnosis and correlating responses to various treatment modalities.

Eosinophilic oesophagitis: improving diagnosis and therapy - reducing the burden of repeated endoscopy

Eosinophilic oesophagitis is now being diagnosed more often, although there continues to be a significant delay in the recognition of the condition in primary care, and among patients presenting with food bolus obstruction to other specialities like Ears, Nose and Throat and Accident & Emergency. The diagnosis requires endoscopy and biopsy, with six biopsies taken from at least two different areas of the oesophagus. The diagnostic threshold is > 15 eosinophils/high power field or 0.3 mm². Dietary management although effective is often difficult to carry out due to poor adherence by patients and the need for a specialist dietitian and repeated biopsies. Orodispersible budesonide is very effective for inducing remission and maintaining it long term, with fewer biopsies. Newer targeted biological agents are promising in the treatment of patients who have not responded to conventional treatments. Dilatation of strictures in this condition is safe.