Do endoscopic features suggesting eosinophilic esophagitis represent histological eosinophilia?

Endoscopic Features of Eosinophilic Esophagitis

Edema, rings, exudates, furrows, and strictures (EREFS) represent the major endoscopic features of eosinophilic esophagitis (EoE). The Endoscopic Reference System (EREFS) grading system is easy to learn and apply during daily clinical practice in the diagnosis and follow-up of EoE patients. When endoscopy is performed by an EoE-experienced physician, the EREFS criteria will identify the majority of EoE patients. The EREFS score from the area of greatest involvement of the esophagus should be reported. The EREFS grading system was formally validated as an endoscopy score and several randomized placebo-controlled trials have shown responsiveness of the EREFS score to therapeutic interventions.

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.

Endoscopic approach to eosinophilic esophagitis: American Society for Gastrointestinal Endoscopy Consensus Conference

Endoscopy plays a critical role in caring for and evaluating the patient with eosinophilic esophagitis (EoE). Endoscopy is essential for diagnosis, assessment of response to therapy, treatment of esophageal strictures, and ongoing monitoring of patients in histologic remission. To date, less-invasive testing for identifying or grading EoE severity has not been established, whereas diagnostic endoscopy as integral to both remains the criterion standard. Therapeutic endoscopy in patients with adverse events of EoE may also be required. In particular, dilation may be essential to treat and attenuate progression of the disease in select patients to minimize further fibrosis and stricture formation. Using a modified Delphi consensus process, a group of 20 expert clinicians and investigators in EoE were assembled to provide guidance for the use of endoscopy in EoE. Through an iterative process, the group achieved consensus on 20 statements yielding comprehensive advice on tissue-sampling standards, gross assessment of disease activity, use and performance of endoscopic dilation, and monitoring of disease, despite an absence of high-quality evidence. Key areas of controversy were identified when discussions yielded an inability to reach agreement on the merit of a statement. We expect that with ongoing research, higher-quality evidence will be obtained to enable creation of a guideline for these issues. We further anticipate that forthcoming expert-generated and agreed-on statements will provide valuable practice advice on the role and use of endoscopy in patients with EoE.

Mucosal color changes on narrow-band imaging in esophageal eosinophilic infiltration

This study aimed to examine the range of beige colored mucosa (BCM) in patients with esophageal eosinophilic infiltration (EEI) using narrow-band imaging (NBI). In this retrospective study, EEI was confirmed histologically in 12 consecutive patients from January 2014 to December 2017. The BCM tone on NBI without magnifying endoscopy was evaluated, and red, green, and blue (RGB) values of BCM and normal mucosa were measured. BCM was macroscopically classified into 2 groups (bright and dark) using cluster analysis. Histopathological analysis was performed in 1 patient who underwent biopsy for both normal mucosa and BCM. All 12 patients presented with BCM. Endoscopy revealed fixed rings, longitudinal furrows, mucosal edema, and exudate in 3, 12, 10, and 8 patients, respectively. Strictures were absent. Five patients had findings suggestive of gastroesophageal reflux disease. In the cluster analysis, 5 and 7 patients had bright and dark BCM, respectively. Consistent results were noted when we categorized patients according to their macroscopic characteristics. RGB values of the BCM and normal mucosa were measured-normal mucosa: R: 99.8 ± 16.5, G: 121.7 ± 23.1, and B: 93.4 ± 19.2; BCM: R: 152.0 ± 31.3, G: 123.9 ± 35.0, and B: 97.5 ± 29.5. BCM had significantly higher R values than normal mucosa (P = .0001). All parameters were significantly lower in the dark BCM group than in the bright BCM group (P < .001). Histopathological analysis revealed expansion of the epithelial intercellular space, eosinophilic infiltration, and basal cell hyperplasia at the BCM sites. BCM was observed in all cases of EEI. RGB values differed between bright and dark BCM. Assessing BCM tone using NBI is a potentially novel diagnostic method for EEI.

Similarity and difference in the characteristics of eosinophilic esophagitis between Western countries and Japan

Over the past two decades, the incidence and prevalence of eosinophilic esophagitis (EoE) have risen rapidly, especially in Western countries, with cases in Japan also showing a gradual increase in recent years. However, similarities and differences regarding the characteristics of EoE between Western countries and Japan remain to be clearly elucidated. The current clinical guidelines for diagnosis include symptoms related to esophageal dysfunction and dense eosinophilic infiltration in the esophageal epithelium. Most affected patients in Japan are diagnosed incidentally during a medical health check-up and asymptomatic cases with typical endoscopic findings suggestive of EoE are frequently encountered. Clinical characteristics of EoE in Japanese are similar to those seen in Western populations. The predominant symptom is dysphagia, with food impaction extremely rare in Japanese cases. Linear furrows are the most frequently reported characteristic endoscopic finding, while an esophageal stricture or narrow caliber is rarely observed. Treatment strategies for EoE include drugs, dietary restrictions, and endoscopic dilation when the disease is advanced with stricture formation. Although single therapy using a proton-pump inhibitor has been shown to achieve symptomatic and histological response in the majority of patients in Japan, no prospective randomized control studies that evaluated drug or elimination diet therapy have been presented. Overall, EoE has similar clinical characteristics between Japanese and Western populations, while disease severity seems to be milder in Japan. Additional studies are necessary to determine genetic factors, natural history of the disease, and treatment efficacy of drugs and elimination diet as compared to Western populations.

Eosinophilic esophagitis-established facts and new horizons

Despite dramatic advances in our understanding of the pathogenesis and course of disease in the relatively short timeframe since the discovery and first description of eosinophilic esophagitis (EoE) less than three decades ago, many open questions remain to be elucidated. For instance, we will need to better characterize atypical clinical presentations of EoE and other forms of esophageal inflammatory conditions with often similar clinical presentations, nut fulfilling current diagnostic criteria for EoE and to determine their significance and interrelationship with genuine EoE. In addition, the interrelationship of EoE with other immune-mediated diseases remains to be clarified. Hopefully, a closer look at the role of environmental factors and their interaction with genetic susceptibility often in context of atopic predisposition may enable identifying the candidate substances/agents/allergens and potentially earlier (childhood) events to trigger the condition. It appears plausible to assume that in the end—comparable to current concepts in other immune-mediated chronic diseases, such as for instance inflammatory bowel disease or asthma bronchiale—we will not be rewarded with the identification of a “one-and-only” underlying pathogenetic trigger factor, with causal responsibility for the disease in each and every EoE patient. Rather, the relative contribution and importance of intrinsic susceptibility, i.e., patient-driven factors (genetics, aberrant immune response) and external trigger factors, such as food (or aero-) allergens as well as early childhood events (e.g., infection and exposure to antibiotics and other drugs) may substantially differ among given individuals with EoE. Accordingly, selection and treatment duration of medical therapy, success rates and extent of required restriction in dietary treatment, and the need for mechanical treatment to address strictures and stenosis require an individualized approach, tailored to each patient. With the advances of emerging treatment options, the importance of such an individualized and patient-centered assessment will increase even further.

How to approach adult patients with asymptomatic esophageal eosinophilia

As the awareness among gastroenterologists regarding endoscopic features suggesting eosinophilic esophagitis is increasing, individuals without symptoms of esophageal dysfunction are increasingly being found to have esophageal eosinophilia on biopsies performed during upper gastrointestinal endoscopies. However, the course of disease and the management of these asymptomatic individuals with esophageal eosinophilia remain elusive. In this review, we propose a definition of asymptomatic individuals with esophageal eosinophilia and discuss the prevalence, risk factors, and course of disease of this specific patient group. Furthermore, we have established a diagnostic and therapeutic pathway based on the most recent available data.

Symptom-based diagnostic approach for eosinophilic esophagitis

The prevalence of eosinophilic esophagitis (EoE) has been increasing in Japan. Although the diagnosis of EoE is based on simple criteria that include the presence of esophageal symptoms and esophageal eosinophilia on biopsies, there are several important issues associated with the diagnostic approach. Following an extensive literature search, the symptoms of 886 EoE cases in Japanese adults were analyzed and divided into three categories as follows: (1) typical symptoms, such as dysphagia (53%); (2) other upper GI symptoms (40%); and (3) no symptoms found during screening or medical examination, i.e., "asymptomatic esophageal eosinophilia" (19%). The diagnostic approach was reviewed according to these categories as well as according to the presence or absence of esophageal eosinophilia. The present manuscript describes the current therapeutic strategy of EoE and ultimately proposes a symptom-based diagnostic approach for EoE.

Risk of progression to eosinophilic esophagitis in patients with asymptomatic esophageal eosinophilia: A retrospective pilot study

Background and Aim

As the number of patients with eosinophilic esophagitis (EoE) has increased worldwide, the likelihood of diagnosing esophageal eosinophilia (EE) in screening endoscopy has also increased. Many of these EE patients do not display any symptoms (i.e. they display asymptomatic EE: aEE), and the risk of aEE patients developing EoE has yet to be demonstrated.

Methods

A total of 62 250 cases were found in the endoscopic registries of two digestive disease centers in the context of gastric cancer screening from April 2016 to August 2018, and these were reviewed.

Results

Thirty‐seven aEE patients (0.059%) were found in the registries, and the histories of endoscopic findings and symptoms were successfully traced for 29 of them. While 11 aEE (37.9%) patients did not show any change in endoscopic findings, 18 (62.1%) exhibited exacerbation. A comparison of the two groups showed both relative youth and diffuse disease distribution to be independent risk factors for progression (P = 0.0034 and 0.0078, respectively). Of the 18 aEE patients whose findings showed progression, 6 developed EoE (5 (17.2%) developed proton‐pump inhibitor (PPI)‐responsive EoE, and only 1 (3.4%) developed PPI‐resistant EoE). A comparison of the non‐EoE and EoE groups showed relative youth to be an independent risk factor for progression to EoE (P = 0.0146).

Conclusions

While some aEE patients developed symptomatic EE, the existence among them of PPI‐resistant EoE was extremely rare. Younger age and diffuse disease distribution at first detection in endoscopic findings are risk factors for progression to symptomatic EE in aEE patients.

Filaggrin and tight junction proteins are crucial for IL-13-mediated esophageal barrier dysfunction

Eosinophilic esophagitis (EoE) is an allergy-mediated disease that is accompanied by IL-13 overexpression and an impaired esophageal barrier. Filaggrin (FLG) and tight junction (TJ) proteins are considered to contribute to epithelial barrier function. However, their functional involvement in EoE has not been elucidated. Here, we aimed to determine the IL-13-mediated barrier dysfunction and expression of TJ-related proteins in EoE and to characterize interactions among TJ-related proteins involved in the barrier function of the esophageal epithelium. Biopsy specimens from EoE patients were analyzed. Primary human esophageal epithelial cells (HEECs) were cultured using an air-liquid interface (ALI) system. The permeability of TJs was assayed by biotinylation. Transepithelial electrical resistance (TEER) was measured after stimulation with IL-13 and after siRNA silencing of FLG expression. FLG and TJ genes and proteins were assessed by quantitative RT-PCR, Western blot analysis, and immunofluorescent staining. The biotinylation reagent diffused through the paracellular spaces of whole stratified epithelial layers in EoE biopsy samples. The TEER decreased in ALI-cultured HEECs after IL-13 stimulation. Although the protein level of FLG decreased, that of the TJ proteins increased in the mucosa of EoE biopsy samples and in ALI-cultured HEECs after IL-13 stimulation. IL-13 altered the staining patterns of TJ proteins and the epithelial morphology. FLG siRNA transfection significantly decreased TEER. The IL-13-mediated reduced esophageal barrier is associated with the altered expression pattern but not with the levels of TJ-associated proteins. A deficiency of FLG altered the stratified epithelial barrier. NEW & NOTEWORTHY Esophageal permeability to small molecules was increased in patients with eosinophilic esophagitis (EoE) and could be induced by IL-13 in our unique air-liquid interface-cultured primary multilayer human esophageal epithelial cells in vitro. A deficiency of filaggrin disrupted the esophageal stratified epithelial barrier. The decreased esophageal barrier in EoE was associated with the altered staining pattern of tight junction proteins, although the levels of the proteins themselves do not appear to be changed.

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.

The role of endoscopy in eosinophilic esophagitis: from diagnosis to therapy

Eosinophilic esophagitis (EoE) has arisen as a common disorder in current clinical and endoscopic gastroenterology practice. Areas covered: A comprehensive review of the literature to summarize and update different aspects related with the use of endoscopy in the diagnostic workout and treatment of pediatric and adult EoE patients is conducted. Expert commentary: Endoscopic features in EoE are frequently subtle, so were inadverted in some initial reports of the disease. Literature has described a wide number of EoE-associated features, systematized in the EREFS classification, which standardized the grade and severity of exudates, rings, edema, furrows, and strictures. The insufficient reliability of these features to predict eosinophilic inflammation still makes biopsies essential in diagnosing or monitoring EoE. EoE causes half of the food impactions requiring endoscopy; food impaction leads to EoE diagnosis in up to half of cases. Long term consequences of EoE include esophageal remodeling leading to strictures and narrowing, thus impairing symptoms and needs dilation. Recognizing the risks from dilation in EoE required carrying out a safe technique to avoid the high complication rate reported in the early literature. Endoscopic dilation should be considered in patients with esophageal narrowing and dysphagia/food impaction unresponsive to diet or drugs-based anti-inflammatory treatment.

High-definition-iSCAN virtual chromoendoscopy has high sensitivity and specificity for the diagnosis of eosinophilic esophagitis

Background and study aims A major challenge in eosinophilic esophagitis (EoE) is disease recognition during endoscopy as there are no pathognomonic findings. We aimed to determine the utility of high-definition (HD) iSCAN virtual chromoendoscopy (VC) in diagnosis of EoE.

Patients and methods One hundred eighty-nine consecutive patients presenting with dysphagia or food bolus impaction were assessed using HD-iSCAN VC (Pentax, Japan) with biopsies from distal, mid, upper esophagus and from furrows where visible.

Results Of 189 patients, 45 (23.8 %, male = 29, median age 40y) had a histological diagnosis of EoE; 73.3 % of the patients were newly diagnosed. iSCAN endoscopic features of EoE were linear furrows (91 %), edema (77.8 %), rings or tracheal appearance (73.3 %), whitish exudates (26.6 %) and narrowing or stricture (5 %). One patient (2.2 %) had all 5 endoscopic features. Ten patients (22.2 %) had linear furrows, edema,rings or tracheal appearance and whitish exudates on iSCAN, with a positive predictive value (PPV) 100 % (95 % CI 69.1 %-100 %) and negative predictive value (NPV) 80.4 % (95 % CI 73.9 %-86 %). Thirteen patients (29 %) presented with linear furrows, edema and rings or tracheal appearance on iSCAN, with a PPV 100 % (95 % CI 75.3 %-100 %) and NPV 81.8 % (95 % CI 75.3 %-87.2 %). Six patients (13.3 %) had furrows and edema and 6 patients (13.3 %) had furrows and rings or tracheal appearance on iSCAN, with a PPV 100 % (95 % CI 54.1 %-100 %) and NPV 78.69 % (95 % CI 72 %-84.4 %), respectively. The sensitivity and specificity of HD-iSCAN endoscopy were 97.62 % (95 % CI 87.43 %-99.94 %) and 89.58 % (95 % CI 83.40 %-94.05 %). The accuracy of HD-iSCAN endoscopy was 92.47 % (95 % CI 87.67 %-95.56 %).

Conclusion HD-iSCAN endoscopy is sensitive and specific with good accuracy for EoE diagnosis. Linear furrows, edema and tracheal appearance were the most common findings and these 3 endoscopic features had a high predictive value for diagnosis of EoE.

The Endoscopic Reference Score shows modest accuracy to predict histologic remission in adult patients with eosinophilic esophagitis

BACKGROUND

The relationship between the severity of endoscopic signs scored according to the Endoscopic Reference Score (EREFS) and histopathologic signs of eosinophilic esophagitis (EoE) has not been sufficiently explored. We aimed to determine if the EREFS system predicts histopathologic activity in EoE patients.

METHODS

We included 69 patients with EoE (age 35 [IQR 29-48] years; 80% male) who, between 2006 and 2014, underwent esophagogastroduodenoscopy (EGD) during which high-quality endoscopic images were taken and esophageal biopsy specimens were obtained. Per EGD, three or more depersonalized images were scored by an expert endoscopist, and histopathologic signs were scored by a pathologist with gastrointestinal expertise; both in a blinded fashion. The predictive values of endoscopic signs for disease activity (peak eosinophil count) were calculated. In addition, we measured the utility of the EREFS in the follow-up of 35 EoE patients.

KEY RESULTS

Individual endoscopic signs did not correspond to the peak eosinophil count or other histopathologic signs. Although the composite fibrotic signs score, inflammatory signs score, and total EREFS correlated weakly to moderately with the peak eosinophil count, none of these scores had both high positive and negative predictive values for histopathologic disease activity. In the follow-up of 35 patients, lower peak eosinophil counts were not associated with a decrease in endoscopic abnormalities.

CONCLUSIONS & INFERENCES

In adult patients with EoE, the EREFS system correlates with peak eosinophil counts, but their predictive value for disease activity is insufficient for clinical use. Therefore, biopsies remain indispensable for the assessment of disease activity.

Asia-Pacific consensus on the management of gastro-oesophageal reflux disease: an update focusing on refractory reflux disease and Barrett's oesophagus

OBJECTIVE

Since the publication of the Asia-Pacific consensus on gastro-oesophageal reflux disease in 2008, there has been further scientific advancement in this field. This updated consensus focuses on proton pump inhibitor-refractory reflux disease and Barrett's oesophagus.

METHODS

A steering committee identified three areas to address: (1) burden of disease and diagnosis of reflux disease; (2) proton pump inhibitor-refractory reflux disease; (3) Barrett's oesophagus. Three working groups formulated draft statements with supporting evidence. Discussions were done via email before a final face-to-face discussion. We used a Delphi consensus process, with a 70% agreement threshold, using Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria to categorise the quality of evidence and strength of recommendations.

RESULTS

A total of 32 statements were proposed and 31 were accepted by consensus. A rise in the prevalence rates of gastro-oesophageal reflux disease in Asia was noted, with the majority being non-erosive reflux disease. Overweight and obesity contributed to the rise. Proton pump inhibitor-refractory reflux disease was recognised to be common. A distinction was made between refractory symptoms and refractory reflux disease, with clarification of the roles of endoscopy and functional testing summarised in two algorithms. The definition of Barrett's oesophagus was revised such that a minimum length of 1 cm was required and the presence of intestinal metaplasia no longer necessary. We recommended the use of standardised endoscopic reporting and advocated endoscopic therapy for confirmed dysplasia and early cancer.

CONCLUSIONS

These guidelines standardise the management of patients with refractory gastro-oesophageal reflux disease and Barrett's oesophagus in the Asia-Pacific region.

Eosinophilic Esophagitis, Eosinophilic Gastroenteritis, and Eosinophilic Colitis: Common Mechanisms and Differences between East and West

Background

Eosinophilic esophagitis (EoE), eosinophilic gastroenteritis (EGE), and eosinophilic colitis (EoC) have been diagnosed with an increasing frequency over the last decades. All these diseases share pathogenic similarities with respect to triggering by food antigens in the majority of patients once secondary causes of tissue eosinophilia have been excluded. While diagnostic criteria for EoE have been published, the exact criteria for EGE and EoC still need to be defined. This review highlights similarities and differences between affected patients when comparing the Western with the Eastern world.

Summary

The incidence and prevalence of EoE are on the rise in countries from the Western and Eastern world. Very limited epidemiologic data exist regarding EGE and EoC. Characteristics of patients with eosinophilic gastrointestinal disorders regarding gender distribution, age at diagnosis, and associated comorbidities are similar when comparing Eastern with Western countries. Similar modalities are applied to diagnose EoE, EGE, and EoC when comparing Eastern with Western countries. Additionally, comparable therapeutic measures are applied to treat eosinophilic gastrointestinal diseases in Eastern and Western countries. While EoE treatment recommendations are based on increasingly solid evidence, recommendations for the treatment of EGE and EoC are based on low evidence.

Key Messages

Eosinophilic gastrointestinal diseases are diagnosed and treated using similar approaches in Eastern and Western countries. Further efforts should be undertaken to help clarify the underlying pathogenic mechanisms and to establish evidence-based diagnostic and therapeutic protocols.

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.

Systematic review: Eosinophilic esophagitis in Asian countries

AIM: To investigate the prevalence and the clinical characteristics of Asian patients with eosinophilic esophagitis.

METHODS: We conducted a systematic search of the PubMed and Web of Science databases for original studies, case series, and individual case reports of eosinophilic esophagitis in Asian countries published from January 1980 to January 2015. We found 66 and 80 articles in the PubMed and Web of Science databases, respectively; 24 duplicate articles were removed. After excluding animal studies, articles not written in English, and meeting abstracts, 25 articles containing 217 patients were selected for analysis.

RESULTS: Sample size-weighted mean values were determined for all pooled prevalence data and clinical characteristics. The mean age of the adult patients with eosinophilic esophagitis was approximately 50 years, and 73% of these patients were male. They frequently presented with allergic diseases including bronchial asthma, allergic rhinitis, food allergy, and atopic dermatitis. Bronchial asthma was the most frequent comorbid allergic disease, occurring in 24% of patients with eosinophilic esophagitis. Dysphagia was the primary symptom reported; 44% of the patients complained of dysphagia. Although laboratory blood tests are not adequately sensitive for an accurate diagnosis of eosinophilic esophagitis, endoscopic examinations revealed abnormal findings typical of this disease, including longitudinal furrows and concentric rings, in 82% of the cases. One-third of the cases responded to proton pump inhibitor administration.

CONCLUSION: The characteristics of eosinophilic esophagitis in Asian patients were similar to those reported in Western patients, indicating that this disease displays a similar pathogenesis between Western and Asian patients.

Reliability of symptoms and endoscopic findings for diagnosis of esophageal eosinophilia in a Japanese population

BACKGROUND/AIMS

The clinical characteristics of esophageal eosinophilia (EE), which is essential for diagnosis of eosinophilic esophagitis (EoE), have not been fully clarified in a Japanese population. The aim of this study was to analyze the reliability of symptoms and endoscopic findings for diagnosing EE in Japanese individuals.

METHODS

We prospectively enrolled subjects who complained of esophageal symptoms suggesting EoE and/or those with endoscopic findings of suspected EoE at the outpatient clinics of 12 hospitals. Diagnostic utility was compared between the EE and non-EE groups using logistic regression analysis.

RESULTS

A total of 349 patients, including 319 with symptoms and 30 with no symptoms but endoscopic findings suggesting EoE were enrolled. Of those with symptoms, 8 (2.5%) had EE, and 3 were finally diagnosed with EoE. Of those without symptoms but endoscopic findings, 4 had EE. Among 8 symptomatic patients, 7 had abnormal endoscopic findings suspicious of EoE. Although dysphagia was a major symptom in EE, none of the presenting symptoms was useful for diagnosis of EE. Among the endoscopic findings, linear furrow was the most reliable (OR = 41.583).

CONCLUSION

EE is uncommon among patients with esophageal symptoms in Japanese individuals. The most useful endoscopic finding for diagnosis of EE was linear furrow, whereas subjective symptoms were not supportive.

Clinical features of eosinophilic esophagitis: differences between Asian and Western populations

The prevalence and incidence of eosinophilic esophagitis (EoE) have been rapidly increasing in Western countries. It is thought to be more common among Caucasians than other racial or ethnic groups, but epidemiological studies have not been fully evaluated in Asian populations, and its clinical manifestation is rarely documented. In this review, recent reports regarding EoE in Asian countries have been collected, and differences in the clinical features, including symptoms and endoscopic findings, between Asian and Western populations have been evaluated. In Asia, EoE is still much less prevalent than in Western countries. Baseline values for average age, male/female ratio, and personal history of allergic disease were comparable to those in Western populations. Predominant symptoms were dysphagia, and food impaction was extremely rare among Asian patients. Although the frequency of abnormal endoscopic findings varies among studies, over 90% of patients with EoE have shown abnormal findings such as linear furrow, which is the most common findings, in recent prospective studies in Asia. There are few reports regarding the treatment of EoE and no prospective studies evaluating drugs or elimination diet in patient with EoE have been reported in Asia. Overall, EoE had similar clinical characteristics in Asian populations. Because the incidence of EoE could increase in the future with the increase in allergic disorders in Asian countries, large-scale, nationwide prospective studies should be performed to more fully understand the epidemiology and pathophysiology of EoE in Asian populations.