Eosinophilic esophagitis: historical perspective on an evolving disease

Vasoactive Intestinal Peptide Receptor, CRTH2, Antagonist Treatment Improves Eosinophil and Mast Cell-Mediated Esophageal Remodeling and Motility Dysfunction in Eosinophilic Esophagitis

BACKGROUND AND AIMS

Ultrasonography has shown that eosinophils accumulate in each segment of the esophageal mucosa in human EoE, ultimately promoting esophageal motility dysfunction; however, no mechanistic evidence explains how or why this accumulation occurs.

METHODS

Quantitative PCR, ELISA, flow cytometry, immunostaining, and immunofluorescence analyses were performed using antibodies specific to the related antigens and receptors.

RESULTS

In deep esophageal biopsies of EoE patients, eosinophils and mast cells accumulate adjacent to nerve cell-derived VIP in each esophageal segment. qRT-PCR analysis revealed five- to sixfold increases in expression levels of VIP, CRTH2, and VAPC2 receptors and proteins in human blood- and tissue-accumulated eosinophils and mast cells. We also observed a significant correlation between mRNA CRTH2 levels and eosinophil- and nerve cell-derived VIPs in human EoE (p < 0.05). We provide evidence that eosinophil and mast cell deficiency following CRTH2 antagonist treatment improves motility dysfunction in a chronic DOX-inducible CC10-IL-13 murine model of experimental EoE.

CONCLUSIONS

CRTH2 antagonist treatment is a novel therapeutic strategy for inflammatory cell-induced esophageal motility dysfunction in IL-13-induced chronic experimental EoE.

Comparison of viscous budesonide and fluticasone in the treatment of patients with eosinophilic esophagitis: a systematic review and meta-analysis

Background

Steroids are an important pharmacologic treatment in patients with eosinophilic esophagitis (EoE). Fluticasone and budesonide are the 2 main steroid medications used in EOE treatment, but current United States (US) guidelines do not recommend one agent over the other. In this study, we conducted a meta-analysis to compare important patient outcomes when both agents are used.

Methods

A comprehensive search of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus was performed from each database's inception to March 29th, 2023. Two independent reviewers systematically identified trials that compared the effect of budesonide vs. fluticasone in the management of EoE. A meta-analysis was performed using a fixed-effects model. The primary outcome was the histologic response (defined as an eosinophil count <15 per high-power field) which reflects the response to treatment.

Results

Three studies met our inclusion criteria and were included in the analysis, with a total of 272 patients. All studies were carried out in the US and 1 was a randomized controlled trial. Our meta-analysis showed no statistically significant difference with the use of budesonide compared to fluticasone in achieving a histologic response (odds ratio 1.29, 95% confidence interval 0.77-2.14; P=0.34; I2=0%).

Conclusion

Our systematic review and meta-analysis indicated no difference between budesonide and fluticasone in achieving a histologic response in patients with EoE.

Allergies Come Clean: The Role of Detergents in Epithelial Barrier Dysfunction

PURPOSE OF REVIEW

The prevalence and incidence of allergic disease have been rising in Westernized countries since the twentieth century. Increasingly, evidence suggests that damage to the epithelium initiates and shapes innate and adaptive immune responses to external antigens. The objective of this review is to examine the role of detergents as a potential risk factor for developing allergic disease.

RECENT FINDINGS

Herein, we identify key sources of human detergent exposure. We summarize the evidence suggesting a possible role for detergents and related chemicals in initiating epithelial barrier dysfunction and allergic inflammation. We primarily focus on experimental models of atopic dermatitis, asthma, and eosinophilic esophagitis, which show compelling associations between allergic disease and detergent exposure. Mechanistic studies suggest that detergents disrupt epithelial barrier integrity through their effects on tight junction or adhesion molecules and promote inflammation through epithelial alarmin release. Environmental exposures that disrupt or damage the epithelium may account for the increasing rates of allergic disease in genetically susceptible individuals. Detergents and related chemical compounds represent possible modifiable risk factors for the development or exacerbation of atopy.

Allergen-induced NLRP3/caspase1/IL-18 signaling initiate eosinophilic esophagitis and respective inhibitors protect disease pathogenesis

The current report describes a stepwise mechanistic pathway of NLRP3/caspase1/IL-18-regulated immune responses operational in eosinophilic esophagitis (EoE). We show that esophageal epithelial cells and macrophage-derived NLRP3 regulated IL-18 initiate the disease and induced IL-5 facilitates eosinophil growth and survival. We also found that A. fumigatus-exposed IL-18-/- mice or IL-18-neutralized mice are protected from EoE induction. Most importantly, we present that intravascular rIL-18 delivery to ΔdblGATA mice and CD2-IL-5 mice show the development of EoE characteristics feature like degranulated and intraepithelial eosinophils, basal cell hyperplasia, remodeling and fibrosis. Similarly, we show an induced NLRP3-caspase1-regulated IL-18 pathway is also operational in human EoE. Lastly, we present the evidence that inhibitors of NLRP3 and caspase-1 (MCC950, BHB, and VX-765) protect A. fumigatus- and corn-extract-induced EoE pathogenesis. In conclusion, the current study provides a new understanding by implicating NLRP3/caspase1-regulated IL-18 pathway in EoE pathogenesis. The study has the clinical significance and novel therapeutic strategy, which depletes only IL-18-responsive pathogenic eosinophils, not naïve IL-5-generated eosinophils critical for maintaining innate immunity.

Models and Tools for Investigating Eosinophilic Esophagitis at the Bench

Eosinophilic esophagitis (EoE) is an increasingly common food allergy disease of the esophagus that received its medical designation code in 2008. Despite this recency, great strides have been made in the understanding of EoE pathophysiology and type 2 immunity through basic and translational scientific investigations conducted at the bench. These advances have been critical to our understanding of disease mechanisms and generating new hypotheses, however, there currently is only one very recently approved FDA-approved therapy for EoE, leaving a great deal to be uncovered for patients with this disease. Here we review some of the innovative methods, models and tools that have contributed to the advances in EoE discovery and suggest future directions of investigation to expand upon this foundation.

Clinical Features of Eosinophilic Esophagitis: A Single Center Experience in Ecuador

PURPOSE

Data on eosinophilic esophagitis (EoE) in South America is scarce. Moreover, no studies are available in Ecuador. We evaluated the clinical, endoscopic, and histological characteristics of Ecuadorian children with EoE.

METHODS

Medical records of 2,711 children who underwent upper gastrointestinal endoscopy (UGE) between 2009 and 2020 at Hospital Metropolitano de Quito, Ecuador were reviewed. Esophageal mucosal biopsies were obtained from 72 patients and the features of 35 children with EoE were described. EoE was diagnosed when there were more than 15 eosinophils in the esophagus, per high power field.

RESULTS

EoE was diagnosed in 35 children (9.4±4.5 years) with a male predominance (74%). Abdominal pain (51.4%) and vomiting (31.4%) were dominant symptoms. A history of allergic diseases was noted in 47.1% of the children, which mainly included allergic rhinitis (37.1%) and atopic dermatitis (11.4%). The most common endoscopic findings were furrowing (82.9%) and edema (74.3%). All patients were initially treated with proton-pump inhibitors (PPIs). Those who did not respond to PPIs received steroids (5.7%) and diet therapy (5.7%), and five patients were referred to an allergist. Clinical and histological resolution was observed in 65% of the patients who underwent a second UGE after 6-8 weeks of PPI.

CONCLUSION

Our study describes the clinical features of pediatric EoE in Ecuador. This is the first retrospective study in Ecuador that describes the clinical, endoscopic, and histological manifestations of EoE in a small pediatric population. Almost half of the children who underwent a biopsy had EoE.

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.

Eosinophilic esophagitis: an interdisciplinary clinical problem

Eosinophilic esophagitis is a newly described entity of increasing incidence. Previously thought to be a variation of gastroesophageal reflux disease, now it becomes well known among gastroenterologists, allergologists, paediatricians and pathologists. Aetiology of the disease is strongly correlated with atopic and allergic disorders but exact pathogenesis and cellular mechanisms of inflammatory process in the esophagus are still unknown. Diagnostic criteria have been described but diagnostic tools are still in the research and improvement phase. Clinical manifestation varies considerably between age groups, which causes a delay in the course of diagnosis due to improperly recognized symptoms. Since eosinophilic esophagitis is a chronic disease without a tendency to be self-limiting, delayed diagnosis may lead to complications associated with oesophageal tissue remodelling. Some forms of treatment are approved and of great therapeutical value, nevertheless clinical trials of new medications provide new possibilities. Therefore, many questions regarding eosinophilic esophagitis arise and are still unanswered.

Eosinophilic Esophagitis Occurring After Switching to Ultra-Pasteurized Milk: Coincidence or Unrecognized Etiologic Trigger?

Eosinophilic esophagitis (EoE) is an increasingly common cause of dysphagia, food impaction, and abdominal pain. Cow’s milk is a major trigger of EoE, but the exact mechanism remains unclear. We present a case of EoE occurring shortly after switching from regularly pasteurized milk to ultra-pasteurized milk.

Gastrointestinal involvement of primary skin diseases

Less is known about gastrointestinal (GI) involvement of primary skin diseases due to the difference in embryology, histology, microbiology and physiology between integument and alimentary tract. Oesophagus, following the oropharyngeal mucosa, is the most common GI segment affected by primary skin diseases, especially by eosinophilic oesophagitis, lichen planus and autoimmune bullous dermatoses like pemphigus vulgaris, mucosal membrane pemphigoid and epidermolysis bullosa acquisita. Eosinophilic oesophagitis is an emerging chronic atopic disease with oesophageal dysfunction as the typical presentation, and oesophageal narrowing, rings and stricture as late complications. Oesophageal lichen planus mainly involves the proximal to mid-oesophagus in elderly aged women with long-term oral mucosal lesions. In acute attack of pemphigus vulgaris, oesophageal involvement is not uncommon but often neglected and may cause sloughing oesophagitis (oesophagitis dissecans superficialis) with acute GI bleeding in rare cases. GI manifestation of hereditary bradykininergic angio-oedema with colicky acute abdomen mostly affects small intestine, usually in the absence of pruritus or urticaria, and is more severe and long-lasting than the acquired histaminergic form. Strong evidence supports association between inflammatory bowel disease, especially Crohn disease, and hidradenitis suppurativa/acne inversa. Patients with vitiligo need surveillance of autoimmune liver disease, autoimmune atrophic gastritis or coeliac disease when corresponding symptoms become suspect. Melanoma is the most common primary tumour metastatic to the GI tract, with small intestine predominantly targeted. Gastrointestinal involvement is not uncommon in disseminated mycosis fungoides. Extramammary Paget's disease is an intraepidermal adenocarcinoma of controversial origin, and a high association between the anogenital occurrence and colorectal adenocarcinoma has been reported. As GI tract is the largest organ system with multidimensional functions, dermatologists in daily practice should be aware of the gastrointestinal morbidities related to primary skin diseases for an early diagnosis and treatment.

The Global Face of Eosinophilic Esophagitis: Advocacy and Research Groups

Although eosinophilic esophagitis (EoE) has been described in the literature for a substantial period, its recognition as a disease entity on the global stage is still relatively new. It has become a major diagnosis of consideration by medical providers when both adult and pediatric patients present with dysphagia, food impaction, and gastroesophageal reflux-like symptoms. In addition to the clinical work of specialists such as allergy-immunologists and gastroenterologists, the evolution of research organizations and advocacy groups focused on EoE have greatly assisted in bringing attention to, and raising awareness about, this disease. As a result of their efforts, diagnosis and treatment guidelines have been developed, and medical providers now have a specific ICD code for EoE. This represents a new model for the interaction of patients and medical provider, where patients not only advocate for their disorder, but also drive physician education and a patient-centered research agenda and its funding. It should be noted, though, that these organizations and advocacy groups are mainly located in North America and Europe, and as a result, EoE has largely been associated with the Caucasian demographic. However, it has been described in Asia, the Middle East, Latin America, and Africa. Physicians from these areas have increased awareness and understanding in the medical and research communities in their countries through case reports and the establishment and analysis of potential patient cohorts. At this time, the prevalence of EoE in these regions is comparably lower, but this may be due to less recognition and understanding of EoE, as well as medical efforts being directed towards more ubiquitous disease processes, such as infectious diseases. With the support and ongoing work of researchers, patients, and their family members, understanding and recognition of EoE as a clinically significant disease entity will continue to grow.

Prospective assessment of disease-specific quality of life in adults with eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is an important cause of upper gastrointestinal dysfunction in children and adults. The EoE-quality of life (QOL)-A was validated as a disease-specific measure of quality of life in EoE. This study characterized the extent of QOL concerns in a cohort of adult EoE patients and delineated the relationships between QOL and other disease activity measures. One hundred sixty-seven patients enrolled in this prospective cohort study. Patients with established and suspected EoE undergoing endoscopy at a single university-based medical center were recruited. EoE was diagnosed on the basis of the clinical criteria and histologic demonstration of ≥15 eos/hpf while on proton pump inhibition therapy. Sixty five patients undergoing repeat endoscopy during the enrollment period participated twice. Patients provided demographic information and completed symptom assessments and the EoE-QOL-A. Analyses included comparisons with overall QOL as well as QOL subscales. Outcome measures included endoscopic activity using a validated instrument, the EoE Endoscopic Reference Score, and histology. Overall QOL was significantly correlated with dysphagia frequency, intensity, and severity (P < 0.001). Patients who experienced a food impaction in the last 30 days had significantly worse overall QOL (P = 0.009). There was no correlation between overall QOL and years since diagnosis, symptom duration, endoscopic features, or histologic findings. Patient symptoms correlated with endoscopic features of edema, rings, and stricture severity. Histologic activity was highly correlated with severity of endoscopic features. Patients who underwent repeat endoscopy with histologic response demonstrated improved eating and social QOL; however, overall QOL was unchanged. In adults with EoE, patient reported QOL is associated with symptom severity but not endoscopic or histologic features. Disease-specific QOL may complement parameters of biologic activity in the assessment of overall disease burden in EoE.

Emerging Insights into the Esophageal Microbiome

PURPOSE OF REVIEW

Analysis of the esophageal microbiome remains a relatively new field of research, and most studies to date have focused on characterizing the esophageal microbiome in states of health and disease. Microbiome alterations have been implicated in the pathogenesis of inflammatory and neoplastic conditions in the colon and elsewhere in the gastrointestinal tract. The epidemiology of various esophageal conditions including Barrett's esophagus (BE), esophageal adenocarcinoma (EAC), esophageal squamous cell carcinoma (ESCC), and eosinophilic esophagitis (EoE) point to the microbiome as a potential co-factor in disease pathogenesis, and the possibility exists that these microbiome alterations could contribute directly to the inflammatory environments necessary for the carcinogenesis or atopy involved in these conditions.

RECENT FINDINGS

The native esophageal microbiome is similar in composition to the oral microbiome, with a high relative abundance of the phylum Firmicutes and the genus Streptococcus. Limited studies to date suggest that there are certain microbiome alterations associated with esophageal diseases. Additionally, it may be possible to indirectly assess the esophageal microbiome via non-endoscopic means. This raises the possibility that non-invasive microbiome analysis could be used for disease screening and monitoring. Further understanding of the role of the esophageal microbiome in disease pathogenesis, as well as methods for microbiome alteration, may help elucidate future targets for disease modifying therapies, or minimally invasive screening tools in patients at high risk for development of various esophageal conditions.

Diagnosis and Treatment of Eosinophilic Esophagitis in Adults

Eosinophilic esophagitis is a relatively recently discovered disease of increasing incidence and prevalence and is a common cause of dysphagia and food bolus impaction. The definition of eosinophilic esophagitis continues to evolve, most recently with the characterization of proton pump inhibitor-responsive esophageal eosinophilia. The number of high-quality prospective, controlled trials guiding therapeutic decisions in eosinophilic esophagitis has increased steadily over the past several years. Treatment options at present focus on dietary therapy, particularly implementation of a 6-food elimination diet, and medical therapy, primarily the use of swallowed, topical corticosteroids. Proton pump inhibitors play an important role in current management. Conservative esophageal dilation is effective at ameliorating dysphagia in symptomatic patients with esophageal strictures. We conducted an evidence-based review of the diagnosis and treatment options in adults with eosinophilic esophagitis. The understanding of eosinophilic esophagitis continues to be refined. Continued validation of appropriate endpoints, however, is essential to establish the efficacy of existing and novel therapeutic approaches.

Prevalence of eosinophilic oesophagitis in adults presenting with oesophageal food bolus obstruction

AIM: To look at the relationship between eosinophilic oesophagitis (EO) and food bolus impaction in adults.

METHODS: We retrospectively analysed medical records of 100 consecutive patients who presented to our hospital with oesophageal food bolus obstruction (FBO) between 2012 and 2014. In this cohort, 96 were adults (64% male), and 4 paediatric patients were excluded from the analysis as our centre did not have paediatric gastroenterologists. Eighty-five adult patients underwent emergency gastroscopy. The food bolus was either advanced into the stomach using the push technique or retrieved using a standard retrieval net. Biopsies were obtained in 51 patients from the proximal and distal parts of the oesophagus at initial gastroscopy. All biopsy specimens were assessed and reviewed by dedicated gastrointestinal pathologists at the Department of Pathology, University Hospital Geelong. The diagnosis of EO was defined and established by the presence of the following histological features: (1) peak eosinophil counts > 20/hpf; (2) eosinophil microabscess; (3) superficial layering of eosinophils; (4) extracellular eosinophil granules; (5) basal cell hyperplasia; (6) dilated intercellular spaces; and (7) subepithelial or lamina propria fibrosis. The histology results of the biopsy specimens were accessed from the pathology database of the hospital and recorded for analysis.

RESULTS: Our cohort had a median age of 60. Seventeen/51 (33%) patients had evidence of EO on biopsy findings. The majority of patients with EO were male (71%). Classical endoscopic features of oesophageal rings, furrows or white plaques and exudates were found in 59% of patients with EO. Previous episodes of FBO were present in 12/17 patients and 41% had a history of eczema, hay fever or asthma. Reflux oesophagitis and benign strictures were found in 20/34 patients who did not have biopsies.

CONCLUSION: EO is present in approximately one third of patients who are admitted with FBO. Biopsies should be performed routinely at index endoscopy in order to pursue this treatable cause of long term morbidity.

Eosinophilic oesophagitis: a systematic review for otolaryngologists

BACKGROUND

Eosinophilic oesophagitis is a chronic, immune/antigen-mediated oesophageal disease, only recently, but increasingly, recognised in the world literature. It is diagnosed and managed primarily by medical gastroenterologists and allergy specialists, and is a distinct disease entity, affecting both children and adults. Few studies have been published in otolaryngology journals, although otolaryngologists will encounter patients with undiagnosed eosinophilic oesophagitis. Patients may present with dysphagia, bolus obstruction or with other ENT disorders, such as atopic rhinitis, reflecting the underlying systemic allergic disorder.

OBJECTIVE

This paper systematically reviews the evidence base published on the epidemiology, clinical presentation, diagnosis, treatment and prognosis of eosinophilic oesophagitis, particularly as it relates to otolaryngology practice.

Esophageal microbiome in eosinophilic esophagitis

Objective

The microbiome has been implicated in the pathogenesis of a number of allergic and inflammatory diseases. The mucosa affected by eosinophilic esophagitis (EoE) is composed of a stratified squamous epithelia and contains intraepithelial eosinophils. To date, no studies have identified the esophageal microbiome in patients with EoE or the impact of treatment on these organisms. The aim of this study was to identify the esophageal microbiome in EoE and determine whether treatments change this profile. We hypothesized that clinically relevant alterations in bacterial populations are present in different forms of esophagitis.

Design

In this prospective study, secretions from the esophageal mucosa were collected from children and adults with EoE, Gastroesophageal Reflux Disease (GERD) and normal mucosa using the Esophageal String Test (EST). Bacterial load was determined using quantitative PCR. Bacterial communities, determined by 16S rRNA gene amplification and 454 pyrosequencing, were compared between health and disease.

Results

Samples from a total of 70 children and adult subjects were examined. Bacterial load was increased in both EoE and GERD relative to normal subjects. In subjects with EoE, load was increased regardless of treatment status or degree of mucosal eosinophilia compared with normal. Haemophilus was significantly increased in untreated EoE subjects as compared with normal subjects. Streptococcus was decreased in GERD subjects on proton pump inhibition as compared with normal subjects.

Conclusions

Diseases associated with mucosal eosinophilia are characterized by a different microbiome from that found in the normal mucosa. Microbiota may contribute to esophageal inflammation in EoE and GERD.