The increasing incidence and prevalence of eosinophilic oesophagitis outpaces changes in endoscopic and biopsy practice: national population-based estimates from Denmark

Speculation as to why the Frequency of Eosinophilic Esophagitis Is Increasing

PURPOSE OF REVIEW

The frequency of eosinophilic esophagitis (EoE), an immune/antigen-mediated disorder first described in 1993, has been increasing rapidly. The purpose of this review is to consider hypotheses proposed to explain this increase and to speculate on their validity.

RECENT FINDINGS

The hygiene hypothesis attributes the rise of EoE to modern hygienic conditions resulting in fewer childhood infections with microbes that might have protected against allergy development. Microbial dysbiosis, a change in the microbiome's composition and diversity caused by a modern affluent lifestyle, also might contribute to allergic conditions. Environmental factors including modern chemicals contaminating crops, livestock treated with hormones and antibiotics, food additives and processing changes, and pollutants in the air and water conceivably might predispose to EoE. One intriguing hypothesis attributes increasing EoE to increasing use of acid-suppressive medications like proton pump inhibitors, which might prevent peptic digestion of food allergens, increase gastric permeability, and alter the microbiome to favor food allergy development. In a recent pediatric case-control study, use of acid suppressants in infancy was by far the single strongest risk factor identified for later development of EoE. It remains unclear which, if any, of the above factors underlies the rising frequency of EoE. These factors need not be mutually exclusive, and the cause of EoE may well be multifactorial.

Eosinophilic esophagitis in Japan: Focus on response to acid suppressive therapy

Eosinophilic esophagitis (EoE) is a chronic inflammatory condition characterized by esophageal dysfunction and dense eosinophilic infiltration of esophageal epithelium. According to clinical consensus and guidelines published in 2011, esophageal eosinophilia was classified into two entities based on response to proton pump inhibitor (PPI) administration: EoE and PPI-responsive esophageal eosinophilia (PPI-REE). We have performed a series of investigations to determine whether EoE is actually different from PPI-REE. Consistent with Western reports, more than half of our examined patients with symptomatic esophageal eosinophilia suggestive of EoE achieved histological remission with single PPI therapy. Furthermore, our comparisons of clinical, endoscopic, and histopathological findings between patients with EoE and those with PPI-REE revealed nearly no differences between them. We also compared gene expression profiles in mucosal biopsy specimens between those groups and found that microarray findings obtained from PPI-REE patients substantially overlapped with those from EoE patients, suggesting that both represent the same condition or are variations of a single disease. In addition, we have noted that more than half of EoE patients who show resistance to a PPI therapy respond to vonoprazan, a novel potassium-competitive acid blocker that has been shown to provide more potent and sustained suppression of gastric acid secretion than PPIs. Our results indicate that PPI-REE may constitute a subtype of EoE. Based on novel evidence including results obtained in our studies, the most recently updated guidelines have included responders to PPI therapy within the spectrum of EoE, abandoning the term PPI-REE.

Allergic gastroenteritis hospital admission time trends in Australia and New Zealand

AIM

Recent epidemiological studies indicate increases in hospital food allergy-related anaphylaxis admission rates in Australian and New Zealand. The aim of the study was to examine whether non-IgE-mediated food allergy might have increased in parallel.

METHODS

We analysed childhood hospital admissions rates by ICD 10 codes for allergic gastroenteritis (AG) and infective gastroenteritis in Australia and New Zealand between June 1998 and July 2014.

RESULTS

In Australia, most AG-related admissions (73%) occurred in those aged <1 year and increased by 7.3%/year (95% confidence interval (CI) 5.5-9.3, P < 0.0001) from 6.8 to 26.5/10⁵ population. Similar trends were observed for New Zealand; 81% of admissions occurred in those aged <1 year and increased by 9.4%/year (95% CI 5.5-9.3, P < 0.0001) from 7.2 to 30.7/10⁵ population. By contrast there were no significant changes in AG-related admission rates in the older patients and infective gastroenteritis admissions fell in both countries in those aged <1 year; Australia by 4.4%/year (95% CI 4.3-4.6, P < 0.0001) and in New Zealand by 5.8%/year (95% CI 5.4-6.2, P < 0.0001).

CONCLUSION

We observed a fourfold increase in AG-related admission rates in two countries with known high rates of IgE-mediated food allergy/anaphylaxis. If confirmed by other studies, it will be of interest to determine if factors thought to contribute to the increase in IgE-mediated food allergy might also play a role in non-IgE-mediated gastroenterological food allergy syndromes.

Clinical Practice Guidelines for the Assessment of Uninvestigated Esophageal Dysphagia

BACKGROUND AND AIMS

Our aim is to review the literature and provide guidelines for the assessment of uninvestigated dysphagia.

METHODS

A systematic literature search identified studies on dysphagia. The quality of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach. Statements were discussed and revised via small group meetings, teleconferences, and a web-based platform until consensus was reached by the full group.

RESULTS

The consensus includes 13 statements focused on the role of strategies for the assessment of esophageal dysphagia. In patients presenting with dysphagia, oropharyngeal dysphagia should be identified promptly because of the risk of aspiration. For patients with esophageal dysphagia, history can be used to help differentiate structural from motility disorders and to elicit alarm features. An empiric trial of proton pump inhibitor therapy should be limited to four weeks in patients with esophageal dysphagia who have reflux symptoms and no additional alarm features. For patients with persistent dysphagia, endoscopy, including esophageal biopsy, was recommended over barium esophagram for the assessment of structural and mucosal esophageal disease. Barium esophagram may be useful when the availability of endoscopy is limited. Esophageal manometry was recommended for diagnosis of esophageal motility disorders, and high-resolution was recommended over conventional manometry.

CONCLUSIONS

Once oropharyngeal dysphagia is ruled out, patients with symptoms of esophageal dysphagia should be assessed by history and physical examination, followed by endoscopy to identify structural and inflammatory lesions. If these are ruled out, then manometry is recommended for the diagnosis of esophageal dysmotility.

Natural history of eosinophilic esophagitis: a systematic review of epidemiology and disease course

Eosinophilic esophagitis is a chronic immune-mediated esophageal disorder. For its timely diagnosis, clinicians must recognize common symptoms, and understand differences in symptoms across patient groups. The aim of this study is to systematically review the epidemiology and natural history of eosinophilic esophagitis. The MEDLINE, Embase, and Cochrane databases were searched from 1974 to February 2017 for studies describing the epidemiology and natural history of eosinophilic esophagitis. Congress abstracts from 2014 to 2016 were also searched. Search results were screened against predetermined inclusion/exclusion criteria by two independent reviewers, and data extraction was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Of 1376 articles identified, 47 met the inclusion criteria: 20 on epidemiology and 27 on natural history. Incidence and prevalence of eosinophilic esophagitis varied widely across North America and Europe, and increased over time. Incidence increased 131-fold in the Netherlands (1996-2010), 20-fold in Denmark (1997-2006), and 5.1-fold in Calgary, Canada (2004-2008). The most commonly reported symptoms were emesis and abdominal pain in children, and dysphagia and food impaction in adults. Age at diagnosis was 5.9-12.0 years in children, and approximately 30 years in adults. Time between symptom onset and diagnosis was 1.2-3.5 years in children and 3.0-8.0 years in adults. Diagnostic delay was associated with an increased risk of endoscopic features of fibrostenosis. Symptoms of eosinophilic esophagitis differed significantly by age and race. In conclusion, there is an increasing incidence and prevalence of eosinophilic esophagitis. The considerable delay between symptom onset and diagnosis suggests that clinicians do not readily recognize the disease, which may have important clinical ramifications.

Rising incidence and prevalence of adult eosinophilic esophagitis in midwestern Spain (2007-2016)

OBJECTIVES

Epidemiologic studies on eosinophilic esophagitis (EoE) are scarce and patient responders to proton pump inhibitor (PPI) therapy have usually been excluded. We aimed to evaluate population-based incidence rates, prevalence and trends in adult EoE over the past decade, including responders to PPI therapy.

METHODS

We conducted an analysis of a prospectively established case registry in the health area of Cáceres, located in midwestern Spain. From the first EoE case diagnosed in 2007, endoscopy and pathology reports up to December 2016 were manually reviewed. A baseline diagnosis of EoE was confirmed upon symptoms of esophageal dysfunction (dysphagia/food impaction) and esophageal eosinophilia ≥ 15 eos/HPF. All patients were re-evaluated on PPI therapy during follow-up.

RESULTS

A total of 137 patients were diagnosed with EoE during the study period, of whom 63 (46%) achieved clinicohistologic remission on PPI therapy. The prevalence of autoimmune disorders was low. Mean incidence rate was 8.09 new cases/100,000 inhabitants/year, increasing to 9.95 during the last lustrum and peaking in 2016 with 13.7. This trend coincided with late declining of esophageal biopsies rate. Overall prevalence in 2016 was 81.73 patients/100,000 inhabitants, with the highest prevalence in males between age 35 and 44 years (273 cases/100,000). No seasonal variation was observed in the diagnosis of EoE (53% during pollen season vs. 47%, p = 0.4).

CONCLUSIONS

In midwestern Spain, incidence (13.7 cases/100,000 inhabitants/year) and prevalence (81.73 patients/100,000 inhabitants) in 2016 have grown remarkably in just one decade, coming closer to those figures recently reported for Crohn's disease in Spain.

Eosinophilic Esophagitis: Incidence and Prevalence

Eosinophilic esophagitis (EoE) is a rapidly emerging allergy-mediated condition encountered frequently in clinical practice. It presents with failure to thrive, nausea, and vomiting in children and is a common reason for dysphagia and food impaction in adults. Several institution-based and population-based studies have reported the frequency of EoE over the past few years. The incidence and prevalence of EoE vary depending on the method of data collection. In population-based studies using national registries, the incidence appears to be increasing, currently estimated to be approximately 10 cases/100,000 persons annually, whereas the prevalence is reported between 10 and 57 cases/100,000 persons.

Diagnosis and Treatment of Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is a new disease. It is caused by a T-helper type 2 cell response to food antigens in contact with the esophageal mucosa. Although no single feature defines EoE, a constellation of compatible demographic, clinical, endoscopic, and histologic findings establish the diagnosis. Children present with symptoms and endoscopic patterns characteristic of inflammation, whereas adolescents and adults have manifestations of fibrosis and gross esophageal strictures. Clinical and endoscopic scoring systems have helped to standardize diagnosis. There is controversy in EoE research over the optimal endpoint for treatment. Although the most common endpoint is a reduced number of eosinophils in biopsies, changes in symptoms and endoscopic features are becoming important targets of therapy. We should improve our understanding of EoE progression and the need for maintenance therapy, and continue development of diagnostic tools that avoid endoscopy and biopsy analyses to more easily monitor disease activity.

Eosinophilic Esophagitis Clinical Manifestations and Differential Diagnosis

As a chronic inflammatory disease with eosinophilic infiltrate of the esophagus, eosinophilic esophagitis (EoE) causes a variety of gastrointestinal (GI) clinical manifestations. None of the symptoms, endoscopic features, or biopsy findings is pathognomonic of the disease, even with high degrees of esophageal eosinophilia. The pathogenesis has been explored by several studies, yet it still far from being completely understood. Evidence supports a role of allergen-driven Th2 lymphocyte mechanism, though not in every patient. This article addresses the disease's clinical manifestations, endoscopic findings, diagnosis, and differential diagnoses. In addition to the current diagnostic criteria, we summarize some recently emerging procedures that promise of enhancing more precise diagnosis and institution of early appropriate management, with consequent better quality of life and reduction of complications.

Epidemiology and Natural History of Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) has emerged over the past 2 decades as a major cause of upper gastrointestinal morbidity. Over this time, the epidemiology of EoE has also rapidly evolved. EoE has transformed from a rare case-reportable condition to disease that is commonly encountered in the gastroenterology clinic, hospital emergency room, and endoscopy suite. The incidence and prevalence are increasing at rates that outpace increased disease recognition. Current incidence estimates range from 5 to 10 cases per 100,000, and current prevalence estimates range from 0.5 to 1 case per 1000. We review the data and potential reasons behind this increase, examine risk factors, and identify important areas for research into disease etiology. The article also discusses the progression of EoE from an inflammatory to fibrostenotic phenotype. An accurate view of the natural history of EoE is central to discussions with patients regarding disease prognosis and decisions about long-term use of medical, endoscopic, and diet therapies. Progressive remodelling appears to be gradual, but not universal, and the duration of untreated disease is the best predictor of stricture risk. Ultimately, prospective, long-term outcome studies focusing on multiple aspects of disease activity are needed to fully understand the natural history of EoE.

Incidence of eosinophilic esophagitis in the Netherlands continues to rise: 20-year results from a nationwide pathology database

BACKGROUND

The incidence of eosinophilic esophagitis (EoE) has increased rapidly. Most epidemiologic data were gathered in single-center studies over a short timeframe, possibly explaining the heterogeneous incidences.

AIM

The aim of this study was to retrospectively estimate the Dutch nationwide incidence of EoE over the last 20 years.

METHODS

The Dutch pathology registry (PALGA) was queried to identify pathology reports describing esophageal eosinophilia from 1996 to 2016. Cases were eligible if EoE was confirmed by the pathologist. Using the annual Dutch population data, the incidence of EoE was calculated.

KEY RESULTS

The search yielded 11 288 reports of which 5080 described esophageal eosinophilia. Eosinophilic esophagitis was diagnosed in 2161 patients, 1574 (73%) males and 365 (17%) children. The incidence increased from 0.01 (95% CI 0-0.02) in 1996 to 2.07 (95% CI 2.05-2.23) per 100 000 inhabitants in 2015. The incidence was higher in males than in females, 3.02 (95% CI 2.66-3.41) vs 1.14 (95% CI 0.93-1.38), odds ratio (OR) 2.66 (95% CI 2.10-3.36) and higher in adults than in children, 2.23 (95% CI 1.99-2.49) vs 1.46 (95% CI 1.09-1.91), OR 1.78 (95% CI 1.32-2.40). Incidence of EoE increased more than 200-fold, whereas endoscopy rates only tripled, from 30 in 1996 to 105 per 100 000 inhabitants in 2015. We observed no seasonal variation.

CONCLUSIONS AND INFERENCES

In the last decades, the Dutch EoE incidence has increased tremendously and still continues to rise. This expansion is only partially driven by increased endoscopy rates.

Normalized serum eosinophil peroxidase levels are inversely correlated with esophageal eosinophilia in eosinophilic esophagitis

Eosinophil peroxidase is an eosinophil-specific, cytoplasmic protein stored in the secondary granules of eosinophils. While eosinophil peroxidase deposition is increased in the esophagus in eosinophilic esophagitis (EOE), its potential role as a peripheral marker is unknown. This study aims to examine the relationship between serum eosinophil peroxidase and esophageal eosinophilia in eosinophilic esophagitis. Prospectively collected serum from 19 subjects with incident EoE prior to treatment and 20 non-EoE controls were tested for serum eosinophil peroxidase, eosinophilic cationic protein, and eosinophil derived neurotoxin using ELISA. Matching esophageal tissue sections were stained and assessed for eosinophil peroxidase deposition using a histopathologic scoring algorithm. Mean peripheral blood absolute eosinophil counts in eosinophilic esophagitis subjects were significantly elevated compared to controls (363 vs. 195 cells/μL, P = 0.008). Absolute median serum eosinophil peroxidase, eosinophil cationic protein, and eosinophil derived neurotoxin did not differ between groups; however, when normalized for absolute eosinophil counts, eosinophilic esophagitis subjects had significantly lower median eosinophil peroxidase levels (2.56 vs. 6.96 ng/mL per eos/μL, P = 0.002, AUC 0.79 (0.64, 0.94 95% CI)). Multivariate analysis demonstrated this relationship persisted after controlling for atopy. Esophageal biopsies from eosinophilic esophagitis subjects demonstrated marked eosinophil peroxidase deposition (median score 46 vs. 0, P < 0.0001). Normalized eosinophil peroxidase levels inversely correlated with esophageal eosinophil density (r = -0.41, P = 0.009). In contrast to marked tissue eosinophil degranulation, circulating eosinophils appear to retain their granule proteins in EoE. Investigations of normalized serum eosinophil peroxidase levels as a biomarker of EoE are ongoing.

Diagnosis and Management of Eosinophilic Esophagitis

Unlike traditional food allergies, immunoglobulin E (IgE) is not a key mediator of eosinophilic esophagitis (EoE). Nonetheless, foods antigens are important triggers of EoE, and allergists play an important role in management of this chronic disease. This review addresses insights into the diagnosis and management as it relates to our evolving understanding about the pathogenesis of EoE.

Quality standards in upper gastrointestinal endoscopy: a position statement of the British Society of Gastroenterology (BSG) and Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland (AUGIS)

This document represents the first position statement produced by the British Society of Gastroenterology and Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland, setting out the minimum expected standards in diagnostic upper gastrointestinal endoscopy. The need for this statement has arisen from the recognition that while technical competence can be rapidly acquired, in practice the performance of a high-quality examination is variable, with an unacceptably high rate of failure to diagnose cancer at endoscopy. The importance of detecting early neoplasia has taken on greater significance in this era of minimally invasive, organ-preserving endoscopic therapy. In this position statement we describe 38 recommendations to improve diagnostic endoscopy quality. Our goal is to emphasise practices that encourage mucosal inspection and lesion recognition, with the aim of optimising the early diagnosis of upper gastrointestinal disease and improving patient outcomes.

Early-life environmental exposures interact with genetic susceptibility variants in pediatric patients with eosinophilic esophagitis

BACKGROUND

Although eosinophilic esophagitis (EoE) is associated with certain gene variants, the rapidly increasing incidence of EoE suggests that environmental factors contribute to disease development.

OBJECTIVE

We tested for gene-environment interaction between EoE-predisposing polymorphisms (within TSLP, LOC283710/KLF13, CAPN14, CCL26, and TGFB) and implicated early-life factors (antibiotic use in infancy, cesarean delivery, breast-feeding, neonatal intensive care unit [NICU] admission, and absence of pets in the home).

METHODS

We conducted a case-control study using hospital-based cases (n = 127) and control subjects representative of the hospital catchment area (n = 121). We computed case-only interaction tests and in secondary analyses evaluated the combined and independent effects of genotype and environmental factors on the risk of EoE.

RESULTS

Case-only analyses identified interactions between rs6736278 (CAPN14) and breast-feeding (P = .02) and rs17815905 (LOC283710/KLF13) and NICU admission (P = .02) but not with any of the factors examined. Case-control analyses suggested that disease risk might be modifiable in subjects with certain gene variants. In particular, breast-feeding in those with the susceptibility gene variant at rs6736278 (CAPN14) reduced the risk of EoE (adjusted odds ratio, 0.08; 95% CI, 0.01-0.59). Admission to the NICU in those without the susceptibility gene variant at rs17815905 (LOC283710/KLF13) significantly increased the risk of having disease (adjusted odds ratio, 4.83; 95% CI, 1.49-15.66).

CONCLUSIONS

The interplay of gene (CAPN14 and LOC283710/KLF13) and early-life environment factors (breast-feeding and NICU admission) might contribute to EoE susceptibility.

Causes and Outcomes of Esophageal Perforation in Eosinophilic Esophagitis

GOALS

To characterize patients who suffer perforation in the context of eosinophilic esophagitis (EoE) and to identify predictors of perforation.

BACKGROUND

Esophageal perforation is a serious complication of EoE.

MATERIALS AND METHODS

We conducted a retrospective cohort study of the University of North Carolina EoE clinicopathologic database from 2001 to 2014. Subjects were included if they had an incident diagnosis of EoE and met consensus guidelines, including nonresponse to a PPI trial. Patients with EoE who had suffered perforation at any point during their course were identified, and compared with EoE cases without perforation. Multiple logistic regression was performed to determine predictors of perforation.

RESULTS

Out of 511 subjects with EoE, 10 (2.0%) had experienced an esophageal perforation. Although those who perforated tended to have a longer duration of symptoms before diagnosis (11.4 vs. 7.0 y, P=0.13), a history of food impaction (odds ratio, 14.9; 95% confidence interval, 1.7-129.2) and the presence of a focal stricture (odds ratio, 4.6; 95% confidence interval, 1.1-19.7) were the only factors independently associated with perforation. Most perforations (80%) occurred after a prolonged food bolus impaction, and only half of individuals (5/10) carried a diagnosis of EoE at the time of perforation; none occurred after dilation. Six patients (60%) were treated with nonoperative management, and 4 (40%) required surgical repair.

CONCLUSIONS

Esophageal perforation is a rare but serious complication of eosinophilic esophagitis, occurring in ∼2% of cases. Most episodes are due to food bolus impaction or strictures, suggesting that patients with fibrostenotic disease due to longer duration of symptoms are at increased risk.

Management of Eosinophilic Esophagitis Based on Pathophysiological Evidence

Over the past decades eosinophilic esophagitis (EoE) has been increasingly diagnosed, and significant progress has been made in our understanding of its pathophysiology. As EoE cannot be cured yet, treatment goals are suppression of disease activity and symptoms as well as the prevention of progression to a more severe disease phenotype. Disease-modifying treatment options can be divided into dietary therapy and immunosuppressive medications, of which topical steroids have been most investigated, yet are still prescribed off-label. In this review, we will summarize recent advances in our understanding of EoE and discuss the mechanisms of action of current treatment options, with emphasis on the role of the esophageal epithelial barrier and the effects of proton-pump inhibitors in the management of patients with EoE.

Management of refractory eosinophilic oesophagitis

The goal of this Review is to discuss the clinical approach to patients who do not respond to treatment for eosinophilic oesophagitis (EoE). Refractory EoE is challenging to manage as there are limited data to guide decision-making. In this Review, refractory EoE is defined as persistent eosinophilia in the setting of incomplete resolution of the primary presenting symptoms and incomplete resolution of endoscopic findings following a PPI trial, and after treatment with either topical steroids or dietary elimination. However, this definition is controversial. This Review will examine these controversies, explore how frequently non-response is observed, and highlight potential explanations and predictors of non-response. Non-response is common and affects a large proportion of patients with EoE. It is important to systematically assess multiple possible causes of non-response, as well as consider treatment complications and an incorrect diagnosis of EoE. If non-response is confirmed, second-line treatments are required. Although the overall response rate for second-line therapy is disappointing, with only half of patients eventually responding, there are several promising agents that are currently under investigation, and the future is bright for new treatment modalities for refractory EoE.

Montelukast Does not Maintain Symptom Remission After Topical Steroid Therapy for Eosinophilic Esophagitis

BACKGROUND & AIMS

Montelukast, a cysteinyl leukotriene type-1 receptor blocker, has been shown in small retrospective studies to reduce symptoms in patients with eosinophilic esophagitis (EoE). We performed a randomized, placebo-controlled, double-blind trial to determine whether montelukast maintains symptomatic remission induced by topical steroid therapy in patients with EoE.

METHODS

We performed a prospective study of adult patients with EoE (solid-food dysphagia and a peak esophageal eosinophil count of >20 cells/high-powered field) enrolled at the Mayo Clinic in Rochester, Minnesota, from April 2008 through February 2015. All patients had been treated previously for at least 6 weeks with a topical steroid until their symptoms were in remission. Steroids were discontinued and patients then were assigned randomly to groups given montelukast (20 mg/day, n = 20) or placebo (n = 21) for 26 weeks (groups were matched for age, sex, history of allergic disease, reflux symptoms, and endoscopic findings of EoE). Study participants were assessed via a structured telephone interview at weeks 2, 4, 8, 12, 16, 20, and 24. Remission was defined as the absence of solid-food dysphagia.

RESULTS

Based on an intention-to-treat analysis, after 26 weeks, 40.0% of subjects in the montelukast group and 23.8% in the placebo group were in remission. The odds ratio for remission in the montelukast group was 0.48 (95% confidence interval, 0.10-2.16) (P = .33). No side effects were reported from either group.

CONCLUSIONS

In a randomized controlled trial of the ability of montelukast to maintain remission in patients in remission from EoE after steroid therapy, we found montelukast to be well tolerated; 40% of patients remained in remission, but this proportion did not differ significantly from that of the placebo group. ClinicalTrials.gov no: NCT00511316.

Clinical symptom tool that raises the index of suspicion for eosinophilic oesophagitis in adults and drives earlier biopsy for definitive diagnosis

BACKGROUND

Eosinophilic oesophagitis (EoE) and gastro-oesophageal reflux disease (GERD) present with overlapping symptomatology and it is challenging to distinguish EoE from GERD clinically before endoscopy.

AIM

To investigate the prognostic value of a set of clinical symptoms and laboratory values in patients with EoE and GERD.

METHODS

In this prospective, single-centre, observational study, we compared clinical and laboratory data from 202 patients with EoE or GERD (10 relevant characteristics). Those characteristics showing potential significance in a univariate analysis were then included in a multivariate analysis.

RESULTS

The set of 10 characteristics (10-marker set) was able to distinguish between EoE and GERD with good reliability (correct assignment, i.e. agreement with subsequent EGD, of 94.4%). Reduction of the set to the six statistically and clinically most relevant markers continued to give good reliability (88.9%), and further stepwise reduction led to four-marker sets comprising history of atopy, history of food impaction, proton pump inhibitor refractory symptoms and either immunoglobulin E or peripheral eosinophilia, with correct assignment rates of 91.3% and 85.1% respectively.

CONCLUSIONS

We have developed a simple and easily applicable clinical/laboratory marker set that helps to distinguish EoE from GERD earlier in the treatment course, thus guiding the endoscopist to perform biopsies from the oesophagus to ensure the diagnosis. The application of the scoring system is expected to diagnose EoE earlier and avoiding delay of adequate treatment.

Specific locations of linear furrows in patients with esophageal eosinophilia

BACKGROUND AND AIM

Linear furrows are the most frequently found endoscopic abnormality in patients with esophageal eosinophilia (EE); however, the precise endoscopic features remain to be fully elucidated. Here, we aimed to clarify the endoscopic features of EE, essential for the diagnosis of eosinophilic esophagitis (EoE), by focusing on the specific locations of linear furrows in a Japanese population.

METHODS

We enrolled 70 cases with EE (≥15 eosinophils/high-power field) who were diagnosed at our hospital and related facilities. Information regarding endoscopic findings and clinical parameters was retrospectively reviewed. Next, the position of linear furrows in relation to esophageal longitudinal folds (ridge or valley) was evaluated in each case and compared with the position of mucosal breaks in patients with reflux esophagitis. Finally, the relationship between linear furrows and eosinophilic infiltration was evaluated.

RESULTS

Of the 70 EE patients, 63 (90%) had linear furrows. Those occurred in a radial pattern and were widespread throughout the lower to upper esophagus, and exclusively found in esophageal longitudinal mucosal fold valleys, not on ridges, which was different from the position of mucosal breaks in patients with reflux esophagitis. Increased eosinophilic infiltration was significantly more frequent in linear furrows in the valleys (93%) as compared to mucosa on adjacent ridges (60%) (P < 0.05).

CONCLUSION

Investigation of these endoscopic characteristics, especially by focusing on linear furrows in esophageal mucosal fold valleys, may provide important clues for more accurate diagnosis of EoE.

Range of pathologies diagnosed using a minimally invasive capsule sponge to evaluate patients with reflux symptoms

AIMS

Reflux symptoms are highly prevalent and non-specific; hence, in the absence of alarm symptoms, endoscopy referral decisions are challenging. This study evaluated whether a non-endoscopic Cytosponge could detect benign oesophageal pathologies and thus have future potential in triaging patients with persistent symptoms.

METHODS AND RESULTS

Two complementary cohorts were recruited: (i) patients with reflux symptoms and no prior endoscopy (n = 409), and (ii) patients with reflux symptoms referred for endoscopy (n = 411). All patients were investigated using the Cytosponge and endoscopy. Significant epithelial inflammation was present in 130 (16%) Cytosponge samples, 32 of which had ulcer slough. Candida and significant inflammation was detected in a further 22 (2.3%) cases; epithelial infiltration with >15 eosinophils/high-power field reflecting possible eosinophilic oesophagitis (EOE) in five (0.6%); and viral inclusions suggestive of herpes oesophagitis in one (0.1%). No significant pathology was detected in the majority, 662 (81%), of Cytosponge samples. Cytosponge and endoscopy findings were in agreement in 574 (70%) cases, in 165 (67%) of the discordant cases one investigation showed mild inflammation while the other was negative, with an additional 22 (8.9%) differing on the extent of inflammation. Eighteen cases with severe inflammation, six with candida and two with EOE were detected only at endoscopy, while 18 with candida and significant inflammation, 13 with ulcer slough, one probable EOE and one viral oesophagitis were identified on the Cytosponge only.

CONCLUSIONS

The Cytosponge detects a range of benign oesophageal pathologies, and therefore has potential clinical utility in the triaging of patients with troublesome reflux symptoms. This warrants further investigation.

Determination of esophageal eosinophil counts and other histologic features of eosinophilic esophagitis by pathology trainees is highly accurate

Many studies of eosinophilic esophagitis (EoE) use expert pathology review, but it is unknown whether less experienced pathologists can reliably assess EoE histology. We aimed to determine whether trainee pathologists can accurately quantify esophageal eosinophil counts and identify associated histologic features of EoE, as compared with expert pathologists. We used a set of 40 digitized slides from patients with varying degrees of esophageal eosinophilia. Each of 6 trainee pathologists underwent a teaching session and used our validated protocol to determine eosinophil counts and associated EoE findings. The same slides had previously been evaluated by expert pathologists, and these results comprised the criterion standard. Eosinophil counts were correlated, and agreement was calculated for the diagnostic threshold of 15 eosinophils per high-power field as well as for associated EoE findings. Peak eosinophil counts were highly correlated between the trainees and the criterion standard (ρ ranged from 0.87 to 0.92; P<.001 for all). Peak counts were also highly correlated between trainees (0.75-0.91; P<.001), and results were similar for mean counts. Agreement was excellent for determining if a count exceeded the diagnostic threshold (κ ranged from 0.83 to 0.89; P<.001). Agreement was very good for eosinophil degranulation (κ = 0.54-0.83; P<.01) and spongiosis (κ = 0.44-0.87; P<.01) but was lower for eosinophil microabscesses (κ = 0.37-0.64; P<.01). In conclusion, using a teaching session, digitized slide set, and validated protocol, the agreement between pathology trainees and expert pathologists for determining eosinophil counts was excellent. Agreement was very good for eosinophil degranulation and spongiosis but less so for microabscesses.

Beneficial effect of Lactococcus lactis NCC 2287 in a murine model of eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is a severe inflammatory disease of the esophagus which is characterized histologically by an eosinophilic infiltration into the esophageal tissue. The efficacy of probiotics in the context of atopic diseases has been well investigated but, to date, there has been no study which has evaluated probiotic effects on EoE inflammation. This study sought to identify a probiotic which improves esophageal inflammation in experimental EoE.

METHODS

Two candidate probiotics, Lactococcus lactis NCC 2287 and Bifidobacterium lactis NCC 2818, were tested in a murine model of EoE elicited by epicutaneous sensitization with Aspergillus fumigatus protein extract. Administration of bacterial strains in drinking water was used, respectively, as a preventive or treatment measure, or continuously throughout the study. Inflammatory parameters were assessed in the esophagus, skin, and lungs after allergen challenge.

RESULTS

In this EoE model, supplementation with L. lactis NCC 2287 significantly decreased esophageal and bronchoalveolar eosinophilia but only when given as a therapeutic treatment. No significant effect on eosinophilia was observed when NCC 2287 was given as a preventive or a continuous intervention. NCC 2287 supplementation had no significant effect on immunoglobulin levels, skin symptom scores, or on transepidermal water loss. Supplementation with another probiotic, B. lactis NCC 2818, had no significant effect on esophageal eosinophilia.

CONCLUSION

We identified a L. lactis strain, able to attenuate esophageal eosinophilic inflammation in a preclinical model of EoE. This effect is strain specific and depends on the timing and duration of bacterial supplementation. Confirmation of these observations in human clinical trials is warranted.

Eosinophilic esophagitis in an octogenarian: A case report and review of the literature

INTRODUCTION

Eosinophilic esophagitis (EoE) is a chronic, immune/antigen-mediated disease characterized clinically by symptoms related to esophageal dysfunction and histologically by a marked eosinophilic infiltrate in the esophageal mucosa. What was once considered a rare disease has nowadays become one of the most frequent esophageal diseases in the Western countries, occupying a place just next to the gastroesophageal reflux disease. EoE etiology and pathogenesis remain largely unknown, although most studies consider that allergic and genetic factors play the most important role.

METHODS

We report the case of EoE in an elderly male (octogenarian), giving a brief review of the current data related to epidemiology, pathogenesis, diagnosis, and treatment of the disease.

RESULTS

Dysphagia to solid foods was the leading symptom, and endoscopic findings included white exudates, longitudinal furrows, and concentric mucosal rings, all suggestive for EoE. Diagnosis relied on histological findings in esophageal mucosal biopsies (>30 eosinophils per high power field).He was treated with topical steroids for 8 weeks, symptoms improved gradually and the patient remained in remission at the 8-month follow-up.

CONCLUSION

This case emphasizes that EoE may occur in very old patients and gastroenterologists should have a high index of suspicion of this disorder in any elderly with dysphagia and endoscopic relevant features.

Lack of compliance with consensus recommendations on the diagnosis of eosinophilic esophagitis (EoE) in published prevalence studies. A clinical and systematic review

OBJECTIVE

According to consensus recommendations, the presence of esophageal symptoms, >15 eosinophils/high-power field and unresponsiveness to proton pump inhibitors are required for a diagnosis of eosinophilic esophagitis (EoE). Nevertheless, inconsistency in using these guidelines has been reported in recent publications. The objective of this study was to assess compliance with EoE diagnostic guidelines in published studies on EoE prevalence and to evaluate other clinical and methodological parameters.

METHODS

A systematic review was conducted in articles published between 2008 and 2015 on the prevalence of EoE in unselected adults. Studies using EoE diagnostic definitions were judged to be compliant if they included all three components of the definition, partially compliant if they included two and non-compliant if they included one or none. Esophageal biopsy protocol differences and descriptions of patients' characteristics were determined.

RESULTS

Among the 20 studies included, eight were performed in a hospital setting and 12 in the general population. Only 40.0% of studies were compliant, 35.0% were partially compliant and 25.0% were non-compliant with the EoE diagnostic definition guidelines. In 60.0% of the studies a proton pump inhibitor trial was not administered. Only 30.0% adhered to the recommendations in the esophageal biopsy protocol. A lack of description of the history of atopia and endoscopic characteristics was observed in many studies.

CONCLUSIONS

Partial or non-compliance with the EoE diagnostic definition was observed in most of the published prevalence studies after the publication of the first consensus. The results of these studies might be interpreted taking into account this context.

Prospective assessment of serum periostin as a biomarker for diagnosis and monitoring of eosinophilic oesophagitis

BACKGROUND

Periostin is highly expressed in eosinophilic oesophagitis (EoE), but has not been extensively studied as a non-invasive biomarker.

AIM

To assess whether serum periostin distinguished EoE from controls at baseline, had utility for monitoring treatment response, or was associated with IL-13 levels.

METHODS

This was a sub-analysis of a prospective cohort study of adults undergoing out-patient upper endoscopy. Incident cases of EoE were diagnosed per consensus guidelines. Controls were subjects with either GERD or dysphagia without EoE. EoE patients were treated with swallowed/topical steroids and had repeat endoscopy/biopsy. Serum periostin levels for cases and controls were compared at baseline, and pre/post-treatment levels were compared for cases. Serum IL-13 and tissue expression of periostin were also assessed.

RESULTS

A total of 61 incident EoE cases and 87 controls were analysed. Despite a marked increase in tissue periostin expression in cases, the median baseline serum periostin level was only slightly higher in cases than controls (22.1 ng/mL vs. 20.7; P = 0.04); there was no change in post-treatment levels. There was also no difference in serum periostin for cases by histologic response or atopic status. There was a strong trend towards higher serum IL-13 levels in cases in the highest periostin quartile (57.1 pg/mL vs. 2.6; P = 0.07).

CONCLUSIONS

Serum periostin levels were similar in cases and controls, and there were no changes post-treatment. Given elevated IL-13 levels in the EoE patients with the highest periostin levels, future studies could explore periostin as a biomarker in EoE, perhaps in the setting of anti-IL-13 therapy.

Helicobacter pylori infection is associated with a reduced risk of developing eosinophilic oesophagitis

BACKGROUND

Eosinophilic oesophagitis (EoE) represents a chronic immune-antigen-mediated allergic disease of the oesophagus of still unknown aetiology. Environmental exposure has been postulated to play a pathogenetic role. Helicobacter pylori (H. pylori) infection has been inversely associated with allergic diseases including atopic dermatitis, asthma and allergic rhinitis and H. pylori may play a protective role in these conditions. Little is known about the relationship between EoE and H. pylori.

AIM

To investigate in a case-control study whether H. pylori infection is associated with a reduced risk of developing EoE.

METHODS

H. pylori infection was evaluated by serology in 58 [11(19%) female, 47 (81%) male, median age: 36.5 years, range 20-72 years] patients with a clinical and histologically proven diagnosis of EoE and 116 age and sex-matched controls (1 case: 2 controls). Antibodies against H. pylori were identified by enzyme-linked immunosorbent assay. Patients with H. pylori-specific IgG ≥ 30 enzyme immunounits were classified as H. pylori-positive.

RESULTS

3/58 (5.2%) patients with EoE had serological evidence of H. pylori infection (EoE - H. pylori current infection) and 5/58 (8.6%) reported prior eradication therapy for H. pylori infection (EoE - H. pylori former infection). The control group demonstrated significantly higher seroprevalence of H. pylori (37.9%, P < 0.0001) when compared to patients with EoE. EoE was inversely associated with H. pylori infection [odds ratio (OR) 0.24, 95% confidence interval (CI) 0.11-0.50].

CONCLUSION

Helicobacter pylori infection is inversely associated with EoE. Our results may contribute to further understanding the pathogenesis and evolving aetiology of EoE.

Assessing Early Life Factors for Eosinophilic Esophagitis: Lessons From Other Allergic Diseases

OPINION STATEMENT

Few studies have been conducted to investigate possible early life determinants for eosinophilic esophagitis. An improved understanding of the etiologic factors implicated in disease development would further elucidate possible disease pathogenesis, inform therapeutic targets for disease treatment, and identify possible modifiable factors for disease prevention in genetically susceptible individuals. Although eosinophilic esophagitis is increasing in incidence and prevalence, the disease remains relatively rare, posing challenges for studying etiologic factors in disease development. Eosinophilic esophagitis is believed to be antigen-mediated, and most patients with EoE have concomitant atopic disease. In recent years, the evolution of our understanding of possible etiologic mechanisms in allergic disease has been informed by our understanding of how early life perturbations can lead to dysbiosis in the colonization of the microflora in the gastrointestinal tract and subsequent dysregulated immune development. Perturbations include factors such as antibiotic use, including prenatal, intra-antepartum, and infancy use of antibiotics, Cesarean delivery, preterm delivery, and neonatal intensive care admission. This article provides a review of these recent developments, as they relate to atopic disease, to inform future directions in the study of early life etiologic factors in the development of eosinophilic esophagitis.

Outcomes of Esophageal Dilation in Eosinophilic Esophagitis: Safety, Efficacy, and Persistence of the Fibrostenotic Phenotype

OBJECTIVES

Esophageal dilation is commonly performed in eosinophilic esophagitis (EoE), but there are few long-term data. The aims of this study were to assess the safety and long-term efficacy of esophageal dilation in a large cohort of EoE cases, and to determine the frequency and predictors of requiring multiple dilations.

METHODS

We conducted a retrospective cohort study in the University of North Carolina EoE Clinicopathological Database from 2002 to 2014. Included subjects met consensus diagnostic criteria for EoE. Clinical, endoscopic, and histologic features were extracted, as were dilation characteristics (dilator type, change in esophageal caliber, and total number of dilations) and complications. Patients with EoE who had undergone dilation were compared with those who did not and also stratified by whether they required single or multiple dilations.

RESULTS

Of 509 EoE patients, 164 were dilated a total of 486 times. Those who underwent dilation had a longer duration of symptoms before diagnosis (11.1 vs. 5.4 years, P<0.001). Ninety-five patients (58%) required >1 dilation (417 dilations total, mean of 4.4±4.3 per patient). The only predictor of requiring multiple dilations was a smaller baseline esophageal diameter. Dilation was tolerated well, with no major bleeds, perforations, or deaths. The overall complication rate was 5%, primarily due to post-procedural pain. Of 164 individuals dilated, a majority (58% or 95/164) required a second dilation. Of these individuals, 75% required repeat dilation within 1 year.

CONCLUSIONS

Dilation in EoE is well-tolerated, with a very low risk of serious complications. Patients with long-standing symptoms before diagnosis are likely to require dilation. More than half of those dilated will require multiple dilations, often needing a second procedure within 1 year. These findings can be used to counsel patients with fibrostenotic complications of EoE.

Systematic review with meta-analysis: the incidence and prevalence of eosinophilic oesophagitis in children and adults in population-based studies

BACKGROUND

The recognition of eosinophilic oesophagitis (EoE) has risen sharply, but its current epidemiology is still under debate.

AIM

To estimate accurately the prevalence and incidence rates of EoE, by a systematic review and meta-analysis.

METHODS

MEDLINE, EMBASE and SCOPUS databases were searched for population-based studies on the epidemiology of EoE. Pooled incidence and prevalence rates, male:female and children:adult ratios, and geographical and temporal variations were calculated with random-effects models.

RESULTS

The search yielded 1334 references; the final quantitative summary included 13 population-based studies from North America, Europe and Australia, with the results showing high heterogeneity. The pooled EoE incidence rate was 3.7/100 000 persons/year [95% confidence interval (CI): 1.7-6.5] and was higher for adults (7; 95% CI: 1-18.3) than for children (5.1; 95% CI: 1.5-10.9). The pooled prevalence of EoE was 22.7 cases/100 000 inhabitants (95% CI: 12.4-36), rising to 28.1 (95% CI: 13-49) when studies with a lower risk of bias were considered; prevalence was higher in adults than in children (43.4; 95% CI: 22.5-71.2 vs. 29.5; 95% CI: 17.5-44.7, respectively), and in American compared to European studies. A steady rise in EoE incidence and prevalence rates was observed upon comparison of studies conducted before and after 2008. No significant publication bias was found.

CONCLUSIONS

Eosinophilic oesophagitis is an increasingly common diagnosis in North America and Europe. The population-based incidence and prevalence of eosinophilic oesophagitis vary widely across individual studies, probably due to variations in diagnosis and risk of bias of research. More prospective, large-scale, multicenter studies are needed to evaluate reported data.

Insights into the emerging epidemic of eosinophilic oesophagitis

Eosinophilic oesophagitis (EOE) is a relatively recently recognised condition characterised by an increase in oesophageal eosinophils. EOE occurs in children and adults with a strong male preponderance. There has been a sharp increase in EOE in North America, Europe and Australia. The reasons for this increase remain unclear but are likely to be influenced by genetic and environmental factors, as well as early-life exposures. Based on recent population-based data, the estimated EOE prevalence in the USA is 56.7 per 100,000 persons. The peak prevalence was observed in patients between 35 and 39 years of age. Prevalence figures in Asia and the Middle East generally appear to be lower than in Western countries, but population-based studies are not available. A causal association between coeliac disease and EOE appears unlikely. Data on the seasonal variation of EOE remain inconclusive. Further population-based studies are needed to define the epidemiology of EOE.

Eosinophilic oesophagitis: relationship of quality of life with clinical, endoscopic and histological activity

BACKGROUND

Knowledge about determinants of quality of life (QoL) in eosinophilic oesophagitis (EoO) patients helps to identify patients at risk of experiencing poor QoL and to tailor therapeutic interventions accordingly.

AIM

To evaluate the impact of symptom severity, endoscopic and histological activity on EoE-specific QoL in adult EoE patients.

METHODS

Ninety-eight adult EoE patients were prospectively included (64% male, median age 39 years). Patients completed two validated instruments to assess EoE-specific QoL (EoO-QoL-A) and symptom severity (adult EoE activity index patient-reported outcome) and then underwent esophagogastroduodenoscopy with biopsy sampling. Physicians reported standardised information on EoE-associated endoscopic and histological alterations. The Spearman's rank correlation coefficient was calculated to determine the relationship between QoL and symptom severity. Linear regression and analysis of variance was used to quantify the extent to which variations in severity of EoE symptoms, endoscopic and histological findings explain variations in QoL.

RESULTS

Quality of life strongly correlated with symptom severity (r = 0.610, P < 0.001). While the variation in severity of symptoms, endoscopic and histological findings alone explained 38%, 35% and 22% of the variability in EoE-related QoL, respectively, these together explained 60% of variation. Symptom severity explained 18-35% of the variation in each of the five QoL subscale scores.

CONCLUSIONS

Eosinophilic oesophagitis symptom severity and biological disease activity determine QoL in adult patients with eosinophilic oesophagitis. Therefore, reduction in both eosinophilic oesophagitis symptoms as well as biological disease activity is essential for improvement of QoL in adult patients. Clinicaltrials.gov number, NCT00939263.

Clinical features of Eosinophilic esophagitis in children and adults

Eosinophilic esophagitis (EoE) may affect humans at any age with a predominance for Caucasian males. The clinical manifestation of EoE varies depending on the patient's age. Infants and young children may primarily present with unspecific symptoms such as feeding problems, vomiting and abdominal pain. In adolescents and adults, dysphagia and food impactation become the predominant symptoms. EoE should also be considered in cases of refractory heartburn in both children and adults. Concomitant allergic diseases such as asthma, rhinitis and eczema, as well as peripheral eosinophilia and elevated total serum IgE values are common in pediatric and adult EoE patients. EoE seems to be primarily a food antigen-driven disease, whereas in adults, aeroallergen sensitization may dominate. Endoscopic features of EoE include mucosal edema, furrows, exudates, corrugated rings, strictures, and the so-called crepe paper sign. There appears to be a shift from an inflammatory-predominant phenotype in young childhood towards a more fibrotic phenotype in adolescents and adults. Long-term follow studies suggest that EoE is a chronic and potentially progressive disease causing recurring dysphagia in the majority of cases. The prevalence of strictures significantly increases with the duration of untreated disease, stressing the importance of early diagnosis and consequent treatment of EoE.

Environmental and infectious factors in eosinophilic esophagitis

Identifying possible environmental or infectious etiologic factors for eosinophilic esophagitis (EoE) may offer insight into opportunities for disease prevention and treatment. We reviewed the current literature to assess environmental and infectious factors evaluated in EoE. Few studies have been conducted, however a consistent inverse association between EoE and H. pylori has been described. Several studies suggest a weak association between season and EoE diagnosis, but the evidence is inconclusive. EoE has also been associated with early life factors, including Cesarean delivery and antibiotic use. Larger studies are needed to evaluate these associations more thoroughly. Several papers have speculated the potential for anti-secretory agents to contribute to EoE. This has not been formerly evaluated. In summary, there is significant opportunity in the future to advance our understanding of possible environmental etiologic factors for EoE.

Do We Know What Causes Eosinophilic Esophagitis? A Mechanistic Update

The mechanisms underlying eosinophilic esophagitis (EoE) have been intensely investigated, and significant advances have been made in understanding the pathogenesis of EoE. EoE is defined as a chronic immune/antigen-mediated disease, characterized clinically by symptoms of esophageal dysfunction and histologically by an esophageal eosinophilic infiltrate. In this paper, we will review the current knowledge of EoE pathophysiology based on both animal and human data and discuss possible etiologic mechanisms from the genetic and environmental perspectives. EoE is a Th2-predominant inflammatory process triggered by allergens. Proinflammatory cytokines and chemokines recruit eosinophils and other effector cells, such as mast cells, into the esophageal epithelium, where they cause direct damage and promote esophageal remodeling. The genetic expression profile of EoE has been described, and several single nucleotide polymorphisms have been identified and associated with EoE. While this genetic contribution is important, it is difficult to postulate that EoE is primarily a genetic disease. Given the rapid epidemiologic changes in the incidence and prevalence of EoE over the past two decades, environmental factors may be the driving force. While it is not known what causes EoE in an individual patient at a specific time, the current hypothesis is that there is a complex interaction between genetic factors and environmental exposures that remains to be elucidated.

Seasonal variation in detection of oesophageal eosinophilia and eosinophilic oesophagitis

BACKGROUND

Seasonal variation has been reported in diagnosis of eosinophilic oesophagitis (EoE), but results are not consistent across studies and there are no national-level data in the USA.

AIM

To determine if there is seasonal variation in diagnosis of oesophageal eosinophilia and EoE in the USA, while accounting for factors such as climate zone and geographic variation.

METHODS

This was a cross-sectional study using a USA national pathology database. Patients with oesophageal eosinophilia (≥15 eosinophils per high-power field) comprised the primary case definition and were compared to those with normal oesophageal biopsies. We calculated the crude and adjusted odds of oesophageal eosinophilia by season, as well as by day of the year. Sensitivity analyses were performed using more restrictive case definitions of EoE, and after stratification by climate zone.

RESULTS

Exactly, 14 524 cases with oesophageal eosinophilia and 90 459 normal controls were analysed. The adjusted odds of oesophageal eosinophilia were higher in the late spring and summer months, with the highest odds in July (aOR: 1.13; 95% CI: 1.03-1.24). These findings persisted with increasing levels of oesophageal eosinophilia, as well as across EoE case definitions. Seasonal variation was strongest in temperate and cold climates, and peak diagnosis varied by climate zone.

CONCLUSIONS

There is a mild but consistent seasonal variation in the diagnosis of oesophageal eosinophilia and EoE, with cases more frequently diagnosed during summer months. These findings take into account climate and geographic differences, suggesting that aeroallergens may contribute to disease development or flare.

Advances in clinical management of eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a chronic immune/antigen-mediated clinicopathologic condition that has become an increasingly important cause of upper gastrointestinal morbidity in adults and children over the past 2 decades. It is diagnosed based on symptoms of esophageal dysfunction, the presence of at least 15 eosinophils/high-power field in esophageal biopsy specimens, and exclusion of competing causes of esophageal eosinophilia, including proton pump inhibitor-responsive esophageal eosinophilia. We review what we have recently learned about the clinical aspects of EoE, discussing the clinical, endoscopic, and histological features of EoE in adults and children. We explain the current diagnostic criteria and challenges to diagnosis, including the role of gastroesophageal reflux disease and proton pump inhibitor-responsive esophageal eosinophilia. It is also important to consider the epidemiology of EoE (with a current incidence of 1 new case per 10,000 per year and prevalence of 0.5 to 1 case per 1000 per year) and disease progression. We review the main treatment approaches and new treatment options; EoE can be treated with topical corticosteroids, such as fluticasone and budesonide, or dietary strategies, such as amino acid-based formulas, allergy test-directed elimination diets, and nondirected empiric elimination diets. Endoscopic dilation has also become an important tool for treatment of fibrostenotic complications of EoE. There are a number of unresolved issues in EoE, including phenotypes, optimal treatment end points, the role of maintenance therapy, and treatment of refractory EoE. The care of patients with EoE and the study of the disease span many disciplines; EoE is ideally managed by a multidisciplinary team of gastroenterologists, allergists, pathologists, and dieticians.