Diagnostic utility of major basic protein, eotaxin-3, and leukotriene enzyme staining in eosinophilic esophagitis

Major basic protein is a useful marker to distinguish eosinophilic esophagitis from IBD-associated eosinophilia in children

OBJECTIVES

The incidence of eosinophilic esophagitis (EoE) is 3-5 times greater in patients with inflammatory bowel disease (IBD) compared with the general population. This study aimed to differentiate true EoE from esophageal eosinophilia in IBD patients by evaluating expression of major basic protein (MBP) and interleukin-13 (IL-13) in esophageal biopsies.

METHODS

This retrospective study included subjects who had an esophagogastroduodenoscopy with esophageal biopsies for IBD work up or suspicion for EoE. Patients were classified into 5 groups: EoE with ≥15 eosinophils per high power field (eos/hpf), EoE-IBD with ≥15 eos/hpf, IBD eosinophilia with 1-14 eos/hpf, IBD and control groups. Biopsies were stained with MBP and IL-13 antibodies and the results (% staining/total tissue area), demographic, and clinical findings were compared among the groups.

RESULTS

The median for MBP staining levels in EoE-IBD was 3.8 (interquartile range 1.3-23), significantly lower than in EoE at 52.8 (8.3-113.2), but higher than in IBD eosinophilia at 0.2 (0-0.9; p < 0.001) and negligible in the IBD and control groups. IL-13 expression in EoE was significantly higher only compared with IBD and controls not with EoE-IBD or IBD eosinophilia. MBP predicted EoE with 100% sensitivity and 99% specificity while IL-13 had 83% sensitivity and 90% specificity using cutoff point from the cohort without EoE-IBD patients. Based on MBP cutoff point that distinguished EoE from non EoE, 56% in EoE-IBD were MBP-positive whereas 100% in EoE group (p < 0.05).

CONCLUSIONS

MBP may be an excellent marker in distinguishing true EoE from eosinophilia caused by IBD. Our data implied that MBP together with endoscopic and histologic changes can assist EoE diagnosis in IBD patients.

Non-Invasive and Minimally Invasive Biomarkers for the Management of Eosinophilic Esophagitis beyond Peak Eosinophil Counts: Filling the Gap in Clinical Practice

Eosinophilic esophagitis (EoE) is a chronic esophageal disease that needs lifelong management and follow-up. The diagnosis requires an upper endoscopy with at least one esophageal biopsy demonstrating >15 eosinophils/high-power field, and often occurs with a diagnostic delay of up to ten years, partly due to the absence of valid non-invasive screening tools. In addition, serial upper endoscopies with esophageal biopsies are mandatory to assess the efficacy of any ongoing treatment in patients with EoE. These procedures are invasive, costly, and, when performed without sedation, are often poorly tolerated by patients. Therefore, there is the clinical need to identify reliable non-invasive or minimally invasive biomarkers that could be used to assess disease activity in clinical practice as a surrogate of peak eosinophil counts on esophageal biopsies. This review summarizes evidence on investigational non-invasive or minimally invasive biomarkers for the diagnosis and follow-up of EoE to report on the state of the art in the field and support future research. We discussed eosinophil-derived mediators including eosinophil cationic protein (ECP), eosinophil-derived neurotoxin (EDN, also known as eosinophil protein X), eosinophil peroxidase (EPO), and major basic protein (MBP) as well as other promising non-eosinophil-derived biomarkers. Although several studies have shown the utility of most biomarkers collected from the serum, esophageal luminal secretions, and feces of EoE patients, numerous limitations currently hamper the integration of such biomarkers in clinical practice. Future studies should aim at validating the utility of non-invasive and minimally invasive biomarkers using rigorous protocols and updated consensus criteria for EoE.

Eosinophilic esophagitis auxiliary diagnosis based on a peptide ligand to eosinophil cationic protein in esophageal mucus of pediatric patients

Eosinophilic esophagitis (EoE) is a chronic inflammatory condition of the esophagus characterized by increased number of eosinophils. Currently, EoE diagnosis is based on endoscopic procedures for histopathological examination, eosinophils' counting and, often, in clinical practice, the challenge is the differentiation between EoE and gastroesophageal reflux disease (GERD). Our aim was to develop novel peptide ligand to Eosinophil cationic protein (ECP) present in EoE biopsies of patients with potential to be used for detection. We performed a comparative proteomic analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS) of esophageal biopsies from pediatric patients with eosinophilic esophagitis, gastroesophageal reflux disease and control individuals. Then, phage display technology was used to select peptides against specific up-regulated protein from EoE patients. Twelve phage clones were selected after three biopanning rounds, and the best phage clone reactivity was evaluated by phage-ELISA assay using esophageal mucus samples from 94 pediatric patients. Mass spectrometry showed that eosinophil cationic protein (ECP) was one of the most up-regulated proteins in EoE patients, which is an eosinophil granule protein usually deposited on tissues to mediate remodeling, but in excess may cause fibrosis and hypertrophy, especially in allergic responses. A highly reactive ECP-ligand peptide (E5) was able to distinguish reactive mucus of EoE patients from GERD and the control individuals by Phage-ELISA, achieving a sensitivity of 84.62%, and a specificity of 82.72%. This is the first study that successfully demonstrated an antibody-like peptide targeting ECP at the esophagus mucus as a useful auxilliary tool for EoE diagnosis with a significant association with atopic disorders and dysphagia.ClinicalTrials.gov no.: NCT03069573.

Diagnosis of Pediatric Non-Esophageal Eosinophilic Gastrointestinal Disorders by Eosinophil Peroxidase Immunohistochemistry

BACKGROUND

Diagnosis of non-esophageal eosinophilic gastrointestinal disorders requires quantification of tissue eosinophils. Our objective was to evaluate eosinophil peroxidase (EPX) immunohistochemistry (IHC) as a method for histologic diagnosis of eosinophilic gastritis (EG) and eosinophilic duodenitis (EoD).

METHODS

We performed a retrospective analysis of biopsies from pediatric EG/EoD cases and controls. Subjects with EG or EoD had ≥30 eosinophils per high power field (eos/hpf) in ≥5 hpf in the stomach and/or ≥3 hpf in the duodenum, respectively. Controls had no histopathologic diagnosis recorded. Tissue eosinophil counts were assessed by hematoxylin & eosin stains. EPX stains were assessed using a unique histopathologic scoring system. Slides were digitized and EPX+ staining area/mm2 was quantified by image analysis.

RESULTS

Twenty-six EG/EoD cases and 40 controls were analyzed. EPX scores and EPX/mm2 levels were markedly elevated in EG/EoD (p ≤ 0.0001). Eosinophil density (eos/mm2) correlated strongly with EPX scores and EPX/mm2 levels in the stomach (r ≥ 0.77) and moderately with EPX scores and EPX/mm2 levels in the duodenum (r ≥ 0.52); (p < 0.0001). EPX quantification identified EG/EoD subjects with high diagnostic accuracy (EPX score: AUC = 1 for EG and EoD; EPX/mm2: AUC = 0.98 (95%CI 0.96-1) for EG, AUC = 0.91 (95%CI 0.81-1) for EoD).

CONCLUSION

EPX-based assessment of eosinophilic inflammation may facilitate automated histologic diagnosis.

Clinical features and time trends associated with an endoscopically normal esophagus in active eosinophilic esophagitis

BACKGROUND

A proportion of patients with active eosinophilic esophagitis (EoE) have a normal-appearing esophagus on esophagogastroduodenoscopy (EGD). We aimed to determine the associations between the baseline clinical features and the endoscopically normal esophagus in EoE, as well as time trends in reporting.

METHODS

In this retrospective study of active EoE cases from 2002 - 2018, patients with and without esophageal endoscopic abnormalities were compared. Multivariable logistic regression identified the independent predictors of a normal EGD. The proportion of patients with a normal EGD was determined per year, and before and after the introduction of the first EoE guidelines and the EoE Endoscopic Reference Score (EREFS).

RESULTS

Of 878 EoE patients, 101 (11.5 %) had an endoscopically normal esophagus; they were younger (8.3 vs. 25.4 years), had shorter median symptom duration before diagnosis (2.8 vs. 5.0 years), were less likely to have dysphagia (40 % vs. 76 %) or food impaction (8 % vs. 33 %), and more likely to have abdominal pain (37 % vs. 19 %) (P < 0.01 for all). On multivariable logistic regression, independent predictors of a normal esophagus were younger age (odds ratio [OR] 0.96, 95 % confidence interval [CI] 0.94 - 0.98), abdominal pain (OR 2.03, 95 %CI 1.13 - 3.67), and lack of dysphagia (OR 0.49, 95 %CI 0.26 - 0.93). The proportion of patients with a normal esophagus decreased from 21 % before the first EoE guidelines to 7 % (P < 0.01) after introduction of the EREFS.

CONCLUSIONS

An endoscopically normal esophagus is seen in ~10 % of active EoE patients and should not preclude biopsies; younger age, abdominal pain, and lack of dysphagia are independent predictors. The proportion of normal EGDs decreased over time, suggesting improved recognition of endoscopic findings.

Searching for Noninvasive Predictors of the Diagnosis and Monitoring of Eosinophilic Esophagitis-The Importance of Biomarkers of the Inflammatory Reaction Involving Eosinophils

Background: Invasive and costly endoscopic diagnosis is obligatory for the diagnosis and monitoring of eosinophilic esophagitis (EoE). This study aims to evaluate the usefulness of serum biomarkers involved in eosinophil-mediated inflammation in the management of EoE. Methods: A prospective cohort study was conducted in 58 patients with dysphagia. Each participant completed a health questionnaire, underwent esophagogastroduodenoscopy with esophageal biopsy for histopathological examination and assessment of total, inflammatory and fibrostenotic Eosinophilic Esophagitis Reference Score (EREFS). Serum levels of interleukin 5 (IL-5), interleukin 13 (IL-13), transforming growth factor β1 (TGF-β1), major basic protein (MBP), and eotaxin 3 were determined by enzyme immunoassays. Total of 16 patients meeting the histological criteria for EoE were treated with proton pump inhibitors for 8 weeks, and then the same diagnostics was performed again. Results: Statistically significantly higher concentrations of MBP and TGF-β1 were demonstrated in the group of patients with EoE, while MBP and eotaxin 3 correlated with the peak eosinophil count (PEC). Baseline MBP levels and eotaxin 3 after treatment significantly positively correlated with EREFS. There was a negative correlation between IL-13 and fibrostenotic EREFS. Additionally, after treatment, a negative correlation TGF-β1 was noted with the inflammatory EREFS and a positive correlation with the fibrostenotic EREFS. Conclusions: The potential role of MBP in predicting the diagnosis of EoE, eotaxin 3 in predicting the advancement and correlation of IL-13 and TGF-β1 in differentiating the inflammatory and fibrotic course of the disease may facilitate the management and individualization of EoE therapy.

Eosinophilic esophagitis and asymptomatic esophageal eosinophilia display similar immunohistological profiles

Patients with asymptomatic esophageal eosinophilia (aEE) do not exhibit clinical symptoms because of esophageal dysfunction, although they have endoscopic and histological findings similar to those of eosinophilic esophagitis (EoE). The cause of the symptoms and the differences between aEE and EoE are unclear. The aim of this study is to determine whether aEE and EoE are same disease entities by comparing immune-related tissue biomarkers using immunohistological staining. Esophageal biopsy specimens from 61 patients, including 18 with aEE and 43 with EoE, were analyzed. Immunofluorescence staining was performed to quantify the immune-related tissue biomarkers such as major basic protein, eosinophil-derived neurotoxin, eotaxin-3, and immunoglobulin G4. Data are presented as median (interquartile range). There were no significant differences in clinical, endoscopic, or histological features, between patients with aEE and EoE, with the exception of body mass index. There were no significant differences in all immune-related tissue biomarkers between both groups. In conclusions, EoE and aEE displayed similar immunohistological profiles. Hence, they may be similar disease entities with some common pathogenic mechanisms. Our findings suggest that patients with aEE also have histopathological esophageal inflammation.

Image Analysis of Eosinophil Peroxidase Immunohistochemistry for Diagnosis of Eosinophilic Esophagitis

BACKGROUND

Diagnosis of eosinophilic esophagitis (EoE) requires manual quantification of tissue eosinophils. Eosinophil peroxidase (EPX) is an eosinophil-specific, cytoplasmic granule protein released during degranulation.

AIMS

The objective of this study was to evaluate image analysis of EPX immunohistochemistry as an automated method for histologic diagnosis of EoE.

METHODS

We performed a secondary analysis of prospectively collected esophageal biopsies obtained from adult subjects with EoE and controls. Tissue sections were stained with hematoxylin and eosin (H&E) and evaluated for peak eosinophils per high power field (eos/hpf). The same slides were de-stained and re-stained to detect EPX for direct comparison. Slides were digitized, and EPX staining area/mm² was quantified using image analysis. Paired samples were compared for changes in EPX staining in treatment responders and non-responders.

RESULTS

Thirty-eight EoE cases and 49 controls were analyzed. Among EoE subjects, matched post-treatment biopsies were available for 21 responders and 10 non-responders. Baseline EPX/mm² was significantly increased in EoE subjects and decreased in treatment responders. EPX quantification correlated strongly with eos/hpf (r = 0.84, p < 0.0001) and identified EoE subjects with high diagnostic accuracy (AUC 0.95, p < 0.0001). The optimal diagnostic EPX-positive pixel/area threshold was 17,379 EPX/mm². Several controls (5/49) with < 15 eos/hpf on H&E staining exceeded this cutoff.

CONCLUSIONS

EPX/mm² correlates strongly with eos/hpf, accurately identifies subjects with EoE, and decreases in treatment responders. Automated quantification of intact eosinophils and their degranulation products may enhance pathologic assessment. Future studies are needed to correlate EPX/mm² with symptoms, endoscopic findings, and esophageal distensibility.

Eosinophilic esophagitis and asymptomatic esophageal eosinophilia display similar immunohistological profiles

Patients with asymptomatic esophageal eosinophilia (aEE) do not exhibit clinical symptoms because of esophageal dysfunction, although they have endoscopic and histological findings similar to those of eosinophilic esophagitis (EoE). The cause of the symptoms and the differences between aEE and EoE are unclear. The aim of this study is to determine whether aEE and EoE are same disease entities by comparing immune-related tissue biomarkers using immunohistological staining. Esophageal biopsy specimens from 61 patients, including 18 with aEE and 43 with EoE, were analyzed. Immunofluorescence staining was performed to quantify the immune-related tissue biomarkers such as major basic protein, eosinophil-derived neurotoxin, eotaxin-3, and immunoglobulin G4. Data are presented as median (interquartile range). There were no significant differences in clinical, endoscopic, or histological features, between patients with aEE and EoE, with the exception of body mass index. There were no significant differences in all immune-related tissue biomarkers between both groups. In conclusions, EoE and aEE displayed similar immunohistological profiles. Hence, they may be similar disease entities with some common pathogenic mechanisms. Our findings suggest that patients with aEE also have histopathological esophageal inflammation.

Utility of major basic protein, eotaxin-3, and mast cell tryptase staining for prediction of response to topical steroid treatment in eosinophilic esophagitis: analysis of a randomized, double-blind, double dummy clinical trial

Inflammatory factors in eosinophilic esophagitis (EoE), including major basic protein (MBP), eotaxin-3 (EOT3) and mast cell tryptase (TRP), may predict treatment response to topical corticosteroids (tCS). We aimed to determine whether baseline levels of these markers predict response to tCS for EoE. To do this, we analyzed data from a randomized trial comparing two topical steroids for treatment of newly diagnosed EoE (NCT02019758). A pretreatment esophageal biopsy was stained for MBP, EOT3, and TRP to quantify tissue biomarker levels (cells/mm2). Levels were compared between histologic responders (<15 eos/hpf) and nonresponders (the primary outcome), and endoscopic responders (EREFS<2) and nonresponders. Complete histologic response (<1 eos/hpf) was also assessed, and area under the receiver operator characteristic curve (AUC) was calculated. We also evaluated whether baseline staining predicted symptom relapse in the trial's off-treatment observation phase. Baseline samples were evaluable in 110/111 subjects who completed the randomized trial. MBP levels were higher in nonresponders (n = 36) than responders (704 vs. 373 cells/mm2; P = 0.007), but EOT3 and TRP levels were not statistically different. The combination of all three stains had an AUC of 0.66 to predict response. For complete histologic response, baseline TRP levels were higher in nonresponders (n = 69) than responders (370 vs. 268 mast cells/mm2; P = 0.01), with an AUC of 0.65. The AUC for endoscopic response was 0.68. Baseline staining did not predict symptom recurrence after remission. Pretreatment MBP, EOT3, and TRP levels were not strongly or consistently associated with histologic or endoscopic response to topical steroids. While elevated TRP levels may be associated with nonresponse compared with complete response, the magnitude and predictive utilities were modest. Novel methods for predicting steroid response are still required.

Distal esophagus is the most commonly involved site for strictures in patients with eosinophilic esophagitis

While strictures are common in eosinophilic esophagitis (EoE), there are few data on stricture distribution and characteristics. Our primary aim was to characterize strictures by location in the esophagus in EoE and associated clinical, endoscopic, and histologic features. This was a retrospective study from the UNC EoE Clinicopathologic Database of subjects with esophageal strictures or narrowing from 2002 to 2017. Strictures were categorized as distal esophagus/gastroesophageal junction, mid-esophagus, proximal esophagus, or diffusely narrowed. Stricture location was assessed and compared with clinical, endoscopic, and histologic features, and also with treatment response to diet or topical steroids. Efficacy of combination therapy with dilation and intralesional steroid injection was assessed in a sub-group of patients with strictures. Of 776 EoE cases, 219 (28%) had strictures, 45% of which were distal, 30% were proximal, 5% were mid-esophageal, and 20% had diffuse narrowing. Those with mid-esophageal strictures were younger (P = 0.02) and had shorter symptom duration (P < 0.01). Those with diffuse esophageal narrowing were more likely to be women (57%) and have abdominal pain (25%). There was no association between other clinical, endoscopic, and histologic findings and treatment response based on stricture location. Fourteen patients (8%) received intralesional triamcinolone injection and subsequently achieved a higher mean dilation diameter after injection (13.7 vs. 15.5 mm; P < 0.01). In conclusion, almost half of strictures in EoE patients were in the distal esophagus. Therefore, EoE should be a diagnostic consideration in patients with focal distal strictures and not presumed to be secondary to gastroesophageal reflux disease.

An Increasing Trend of Eosinophilic Esophagitis in Korea and the Clinical Implication of the Biomarkers to Determine Disease Activity and Treatment Response in Eosinophilic Esophagitis

Background/Aims

The epidemiology and pathogenesis of eosinophilic esophagitis (EoE) remain unclear in Asian countries. We investigated clinicopathological characteristics and diagnostic trends of EoE, and evaluated 3 tissue biomarkers for correlation with disease activity and treatment response in Korean patients with EoE.

Methods

We retrospectively reviewed 25 271 esophageal biopsies performed during upper endoscopies between 2006 and 2017. We diagnosed EoE based on ≥ 15 eosinophils/high-power field (HPF) and, symptoms of esophageal dysfunction. We performed immunohistochemical analysis for tryptase, eosinophilic derived neurotoxin (EDN), and eotaxin-3.

Results

We diagnosed EoE in 72 patients (53 men and 19 women; mean age, 46.2 years) with presenting symptoms of, dysphagia (15.3%), epigastric pain (31.9%), and heartburn (30.6%). The diagnostic rate of EoE considerably increased between 2006 and 2017, from 0.29 diagnoses to 7.99 diagnoses per 1000 esophageal biopsies ( P < 0.001). The mean peak eosinophil count (PEC) was 56.0 (± 77.8)/HPF. Whereas the EDN (rho = 0.667, P < 0.001) and eotaxin-3 levels (rho = 0.465, P < 0.001) correlated with PEC, tryptase and PEC were weakly correlated (rho = 0.291, P = 0.013). EDN (rho = 0.279, P = 0.017), and tryptase (rho = 0.279, P = 0.033) correlated with the inflammatory score of Eosinophilic Esophagitis Endoscopic Reference Score. Immunohistochemical analysis and changes in tryptase, EDN, and eotaxin-3 levels were associated with histologic and endoscopic improvements.

Conclusions

EoE incidence considerably increased during the 12-year period, regardless of endoscopic esophageal biopsy rate. Tryptase, EDN, and eotaxin-3 levels in esophageal biopsy specimens could be promising biomarkers for disease activity, symptom, and endoscopic response in Korea.

Eosinophilic Esophagitis: Review and Update

Background: Eosinophilic esophagitis (EoE) was first described in the 1990s, showing an increasing incidence and prevalence since then, being the leading cause of food impaction and the major cause of dysphagia. Probably, in a few years, EoE may no longer be considered a rare disease. Methods: This article discusses new aspects of the pathogenesis, symptoms, diagnosis, and treatment of EoE according to the last published guidelines. Results: The epidemiological studies indicate a multifactorial origin for EoE, where environmental and genetic factors take part. EoE affects both children and adults and it is frequently associated with atopic disease and IgE-mediated food allergies. In patients undergoing oral immunotherapy for desensitization from IgE-mediated food allergy the risk of developing EoE is 2.72%. Barrier dysfunction and T-helper 2 inflammation is considered to be pathogenetically important factors. There are different patterns of clinical presentation varying with age and can be masked by adaptation habits. Besides, symptoms do not usually correlate with histologic disease activity. The diagnostic criteria for EoE has evolved but mainly requires symptoms of esophageal dysfunction with histologic evidence of a peak value of at least 15 eosinophils per high-power field. Endoscopies have to be repeated in order to diagnose, monitor, and treat EoE. Treatment of EoE can be started either by drugs (PPIs and topical corticosteroids) or elimination diets. The multistage step-up elimination diet management approach of EoE is promising. Endoscopic dilation is used for patients with severe dysphagia/food impaction with inadequate response to anti-inflammatory treatment. Conclusions: Research in recent years has contributed to a better understanding of EoE's pathogenesis, genetic background, natural history, allergy workup, standardization in assessment of disease activity, evaluation of minimally invasive diagnostic tools, and new therapeutic approaches. However, several unmet needs are to be solved urgently, as finding a non-invasive disease-monitoring methods and biomarkers for routine practice, the development or new therapies, novel food allergy testing to detect triggering foods, drug, and doses required for initial therapy and safety issues with long-term maintenance therapy, amongst others. Besides, multidisciplinary management units of EoE, involving gastroenterologists, pediatricians, allergists, pathologists, dietitians, and ENT specialists are needed.

Updated International Consensus Diagnostic Criteria for Eosinophilic Esophagitis: Proceedings of the AGREE Conference

BACKGROUND & AIMS

Over the last decade, clinical experiences and research studies raised concerns regarding use of proton pump inhibitors (PPIs) as part of the diagnostic strategy for eosinophilic esophagitis (EoE). We aimed to clarify the use of PPIs in the evaluation and treatment of children and adults with suspected EoE to develop updated international consensus criteria for EoE diagnosis.

METHODS

A consensus conference was convened to address the issue of PPI use for esophageal eosinophilia using a process consistent with standards described in the Appraisal of Guidelines for Research and Evaluation II. Pediatric and adult physicians and researchers from gastroenterology, allergy, and pathology subspecialties representing 14 countries used online communications, teleconferences, and a face-to-face meeting to review the literature and clinical experiences.

RESULTS

Substantial evidence documented that PPIs reduce esophageal eosinophilia in children, adolescents, and adults, with several mechanisms potentially explaining the treatment effect. Based on these findings, an updated diagnostic algorithm for EoE was developed, with removal of the PPI trial requirement.

CONCLUSIONS

EoE should be diagnosed when there are symptoms of esophageal dysfunction and at least 15 eosinophils per high-power field (or approximately 60 eosinophils per mm²) on esophageal biopsy and after a comprehensive assessment of non-EoE disorders that could cause or potentially contribute to esophageal eosinophilia. The evidence suggests that PPIs are better classified as a treatment for esophageal eosinophilia that may be due to EoE than as a diagnostic criterion, and we have developed updated consensus criteria for EoE that reflect this change.

An Evolving Approach to the Diagnosis of Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is a chronic allergic/ immune-mediated esophageal disease. Knowledge related to the clinical presentation, pathogenesis, epidemiology, natural history, treatment, and outcomes of EoE has rapidly evolved over the past 2 decades. This article focuses on the similarly evolving diagnostic framework for EoE. In the initial clinical guidelines, diagnosis of EoE was based on symptoms of esophageal dysfunction; at least 15 eosinophils per high-power field (eos/hpf) on esophageal biopsy; and either a lack of response to high-dose proton pump inhibitor (PPI) therapy, or normal pH monitoring. The first 2 criteria have remained largely unchanged; however, the role of PPIs has been controversial, particularly due to the recognition of PPI-responsive esophageal eosinophilia (PPI-REE), in which patients with suspected EoE experience resolution of symptoms and esophageal eosinophilia with PPI therapy. A quickly expanding evidence base has found that most adult patients with EoE and PPI-REE share similar clinical, endoscopic, histologic, immunologic, and molecular characteristics prior to the use of PPIs. Because of this, the most recent diagnostic guidelines have removed the lack of response to PPIs as a diagnostic criterion; PPIs are now better considered as a treatment for esophageal eosinophilia. EoE should currently be suspected on a clinical basis when there are symptoms of esophageal dysfunction and at least 15 eos/hpf on esophageal biopsies. A history of atopy and endoscopic signs of EoE are strongly supportive of the diagnosis. However, the diagnosis cannot be confirmed until a thorough evaluation of other potential causes of esophageal eosinophilia has been performed.

Optimal Histologic Cutpoints for Treatment Response in Patients With Eosinophilic Esophagitis: Analysis of Data From a Prospective Cohort Study

BACKGROUND AND AIMS

No prospective studies substantiate 15 eos/hpf as an appropriate endpoint for treatment of eosinophilic esophagitis (EoE). We aimed to determine a histologic cutpoint that identifies successful treatment of EoE by assessing symptomatic and endoscopic improvement.

METHODS

We performed a prospective cohort study of 62 consecutive adult patients undergoing outpatient esophagogastroduodenoscopy at the University of North Carolina from 2009 through 2014. At diagnosis of EoE and after 8 weeks of standard treatment, symptom and endoscopic responses were measured using a visual analogue scale and an endoscopic severity score (ESS), and eosinophil counts were assessed. Receiver operator curves and logistic regression models evaluated the histologic threshold that best predicted symptomatic and endoscopic response. For symptoms, analysis was limited to patients without baseline esophageal dilation.

RESULTS

The mean eosinophil count at diagnosis was 124 eos/hpf, falling to 35 eos/hpf after treatment. The mean visual analogue scale decreased from 3.4 at baseline to 1.7 after treatment, and the mean ESS decreased from 3 to 1.6. Twenty-nine patients had symptom responses (47%) and 34 had endoscopic responses (55%). Post-treatment eosinophil count thresholds of 8, 15, and 5 eos/hpf best predicted symptom, endoscopic and combined responses, respectively. On logistic regression, decreasing eosinophil count was significantly associated with the probability of symptomatic (P = .01) and endoscopic response (P < .001).

CONCLUSIONS

In a prospective study of patients with EoE, we found that a cutpoint of <15 eos/hpf identifies most patients with symptom and endoscopic improvements, providing support for the current diagnostic threshold. A lower threshold (<5 eos/hpf) identifies most patients with a combination of symptom and endoscopic responses; this cutpoint might be used in situations that require a stringent histologic threshold.

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.

Control of inflammation decreases the need for subsequent esophageal dilation in patients with eosinophilic esophagitis

It is unknown if successful control of esophageal inflammation in eosinophilic esophagitis (EoE) decreases the need for subsequent esophageal dilation. We aimed to determine whether histologic response to topical steroid treatment decreases the likelihood and frequency of subsequent esophageal dilation. We conducted a retrospective cohort study. Patients with an incident diagnosis of EoE were included if they had an initial esophageal dilation, received topical steroids, and had a subsequent endoscopy with biopsies. The number of dilations performed in each group was determined, and histologic responders (<15 eos/hpf) were compared to nonresponders. The 55 EoE patients included (27 responders and 28 nonresponders) underwent a mean of 3.0 dilations over a median follow-up of 19 months. Responders required fewer dilations than nonresponders (1.6 vs. 4.6, P = 0.03), after adjusting for potential confounders. Despite undergoing significantly fewer dilations, responders achieved a similar increase in esophageal diameter with dilation (4.9 vs. 5.0 mm; P = 0.92). In EoE patients undergoing esophageal dilation at baseline, control of inflammation with topical steroids was associated with a 65% decrease in the number of subsequent dilations to maintain the same esophageal caliber. This suggests that inflammation control is an important goal in patients with fibrostenotic changes of EoE.

Review of Current Applications of Immunohistochemistry in Pediatric Nonneoplastic Gastrointestinal, Hepatobiliary, and Pancreatic Lesions

Immunohistochemical (IHC) stains are widely used by pathologists for a variety of considerations in the diagnostic workup of pediatric nonneoplastic lesions in gastrointestinal (GI), hepatic, biliary, and pancreatic lesions. The pathologic changes cover a wide range and types of presentations, including inflammatory (bacterial and viral), metaplastic, posttransplant lymphoproliferative, autoimmune, metabolic, degenerative, developmental, and genetic conditions, among others. The everyday practical value of IHC stains covers primary identification, confirmation, differential, and/or exclusionary roles in the hands and eyes and minds of the practitioners. This article is intended to review and discuss the currently available IHC stains for a variety of pediatric GI, hepatobiliary, and pancreatic lesions as encountered in the day-to-day practice of pathologists and clinicians. It reflects the most recent methods and types of IHC stains with the stated aim of helping to provide a quick reference for diagnostic considerations and thereby facilitate the workup of a broad range of GI and related conditions in a pediatric population. The tables provide a handy reference on a wide range of IHC stains for commonly encountered lesions covering a variety of pediatric GI, hepatobiliary, and pancreatic conditions that are amenable to light microscopic diagnostic interpretation.

A Gene Expression Panel is Accurate for Diagnosis and Monitoring Treatment of Eosinophilic Esophagitis in Adults

Objective:

Eosinophilic esophagitis (EoE) can be difficult to diagnose. We aimed to evaluate whether a gene expression score could differentiate adult EoE cases from non-EoE controls and to determine whether scores normalized after treatment for EoE.

Methods:

We analyzed prospectively collected esophageal biopsies from EoE patients (diagnosed as per consensus guidelines and after a proton pump inhibitor trial) and non-EoE controls. Gene expression for a previously constructed 94 gene panel was quantified for a single RNA-later preserved biopsy. For diagnosis, a summary expression score and the area under the receiver operating characteristic curve (AUC) were calculated. For treatment response (defined as <15 eosinophils per high-power field), pretreatment and posttreatment EoE samples were compared.

Results:

For 91 EoE cases and 174 controls, gene scores for EoE cases were lower than non-EoE controls (mean 198 vs. 420; P<0.001), with an AUC of 0.927. A score ≤263 yielded a positive predictive value=91% a score ≥349 yielded a negative predictive value=90% only 12% of subjects had an indeterminate score (264–348) by this classification scheme. For the 89 EoE cases with paired pretreatment and posttreatment samples, overall gene scores improved after treatment from 199 to 343 (P<0.001). This normalization was seen only in cases with histological response (202 vs. 425; P<0.001); scores were unchanged in non-responders (189 vs. 226; P=0.25).

Conclusions:

A gene expression score has high diagnostic utility for distinguishing EoE patients from non-EoE controls in adults and can be used in clinical algorithms. Because it is highly responsive to treatment, the test could be used to monitor disease status.

Possible Noninvasive Biomarker of Eosinophilic Esophagitis: Clinical and Experimental Evidence

Eosinophilic esophagitis (EoE) diagnosis and follow-up response to therapy is based on repeated endoscopies and histological examination for eosinophils/HPF. The procedure is invasive and risky in particular for the pediatric population. Presently, there is no highly sensitive and specific noninvasive blood test available to monitor the disease pathogenesis. Reports indicate the expression of PDL1 (CD274) on the eosinophils in allergic patients. Herein, we report that CD274-expressing and -nonexpressing eosinophils were detected in both examined pediatric and adult EoE patients. We show that CD274 expression on blood eosinophils and blood mRNA expression levels increase in the blood of EoE patients and decrease following treatment. These observations are consistent with the esophageal eosinophilia of before and after treatment in both examined patients. These two clinical and experimental analysis reports provide the possibility that the CD274 mRNA and CD274-expressing esinophil levels may be novel possible noninvasive biomarkers for EoE.

The Inflammatory Milieu of Eosinophilic Esophagitis: A Contemporary Review With Emphasis in Putative Immunohistochemistry and Serologic Markers

Eosinophilic esophagitis is a chronic disease characterized by esophageal dysfunction, frequent clinical history of atopy, and eosinophilic inflammation of the esophagus. Within the esophageal mucosa, there is a wide variety of immune mediators, chemotactic factors, mediators of transcription, and markers of epithelial differentiation and integrity that are overexpressed or underexpressed in eosinophilic esophagitis, offering many candidates for biomarkers with diagnostic or prognostic potential. In this review, we summarize the results from studies performed so far to evaluate the detection of these markers by immunohistochemistry on esophageal biopsies. In addition, we briefly describe some attempts to identify markers that could be detected in serum to be used to diagnose or monitor the disease without the need of a biopsy.

The extremely narrow-caliber esophagus is a treatment-resistant subphenotype of eosinophilic esophagitis

BACKGROUND AND AIMS

Some patients with eosinophilic esophagitis (EoE) have an extremely narrow esophagus, but the characteristics of this group have not been extensively described. We aimed to characterize the narrow-caliber phenotype of EoE, determine associated risk factors, and identify differences in treatment response in this subgroup of patients.

METHODS

This retrospective cohort study from 2001 to 2014 included subjects with a new diagnosis of EoE per consensus guidelines. Demographic, endoscopic, histologic, and treatment response data were extracted from medical records. An extremely narrow-caliber esophagus was defined when a neonatal endoscope was required to traverse the esophagus due to the inability to pass an adult endoscope. Patients with and without an extremely narrow-caliber esophagus were compared. Multivariable logistical regression was performed to assess treatment outcomes.

RESULTS

Of 513 patients with EoE, 46 (9%) had an extremely narrow-caliber esophagus. These patients were older (33 vs 22 years; P < .01), had longer symptom duration (11 vs 3 years; P < .01), more dysphagia (98% vs 66%; P < .01), and food impactions (53% vs 31%; P < .01). Dilation was more common with extreme narrowing (69% vs 17%; P < .01). Patients with a narrow-caliber esophagus were more refractory to steroid treatment, with lower symptom (56% vs 85%), endoscopic (52% vs 76%), and histologic (33% vs 63%) responses (P < .01 for all), and these differences persisted after multivariate analysis.

CONCLUSION

The extremely narrow-caliber esophagus is a more treatment-resistant subphenotype of EoE and is characterized by longer symptom duration and the need for multiple dilations. Recognition of an extremely narrow-caliber esophagus at diagnosis of EoE can provide important prognostic information.

A single biopsy is valid for genetic diagnosis of eosinophilic esophagitis regardless of tissue preservation or location in the esophagus

BACKGROUND & AIMS

A new gene expression profile test may distinguish eosinophilic esophagitis (EoE) and gastroesophageal reflux disease (GERD), but the optimal tissue preparation and biopsy location are unknown. We aimed to determine if formalin-fixed paraffin-embedded (FFPE) and RNA-later (RNAL) preserved specimens from newly diagnosed EoE patients have equivalent gene expression scores and whether scores vary by esophageal biopsy location.

METHODS

We analyzed prospectively collected and banked esophageal biopsies from EoE patients and GERD controls. Paired FFPE and RNAL samples from the distal, mid, and proximal esophagus were used. RNA was extracted, and gene expression for a previously constructed 96 gene panel was quantified with a summary expression score. Scores were compared between EoE and GERD patients, between FFPE and RNAL samples, and between the different esophageal locations.

RESULTS

A total of 72 samples, representing paired FFPE and RNAL specimens from 9 EoE cases and 3 GERD controls, were analyzed. Overall median gene expression scores were similar between FFPE and RNAL (238 vs 227; p=0.64), correlation was excellent between FFPE and RNAL (Spearman's rho=0.90; p<0.001), and there were no differences by biopsy level. Median gene scores distinguished EoE from controls (134 vs 402; p=0.02), and overall agreement between preservation methods and EoE case status was perfect (kappa=1.0; p<0.001).

CONCLUSIONS

Gene expression scores were equivalent in FFPE and RNAL, and were also similar across three esophageal locations. This implies that a single biopsy in either FFPE or RNAL from anywhere in the esophagus may have the potential for genetic diagnosis of EoE.

Proton pump inhibitor-responsive oesophageal eosinophilia: an entity challenging current diagnostic criteria for eosinophilic oesophagitis

Consensus diagnostic recommendations to distinguish GORD from eosinophilic oesophagitis (EoE) by response to a trial of proton pump inhibitors (PPIs) unexpectedly uncovered an entity called 'PPI-responsive oesophageal eosinophilia' (PPI-REE). PPI-REE refers to patients with clinical and histological features of EoE that remit with PPI treatment. Recent and evolving evidence, mostly from adults, shows that patients with PPI-REE and patients with EoE at baseline are clinically, endoscopically and histologically indistinguishable and have a significant overlap in terms of features of Th2 immune-mediated inflammation and gene expression. Furthermore, PPI therapy restores oesophageal mucosal integrity, reduces Th2 inflammation and reverses the abnormal gene expression signature in patients with PPI-REE, similar to the effects of topical steroids in patients with EoE. Additionally, recent series have reported that patients with EoE responsive to diet/topical steroids may also achieve remission on PPI therapy. This mounting evidence supports the concept that PPI-REE represents a continuum of the same immunological mechanisms that underlie EoE. Accordingly, it seems counterintuitive to differentiate PPI-REE from EoE based on a differential response to PPI therapy when their phenotypic, molecular, mechanistic and therapeutic features cannot be reliably distinguished. For patients with symptoms and histological features of EoE, it is reasonable to consider PPI therapy not as a diagnostic test, but as a therapeutic agent. Due to its safety profile, ease of administration and high response rates (up to 50%), PPI can be considered a first-line treatment before diet and topical steroids. The reasons why some patients with EoE respond to PPI, while others do not, remain to be elucidated.

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.

Oesophageal intrasquamous IgG4 deposits: an adjunctive marker to distinguish eosinophilic oesophagitis from reflux oesophagitis

AIMS

To explore the utility of an IgG4 immunohistochemical stain to help distinguish eosinophilic oesophagitis from gastroesophageal reflux disease.

METHODS AND RESULTS

We examined 21 cases of eosinophilic oesophagitis and 25 cases of gastroesophageal reflux disease. The diagnosis of eosinophilic oesophagitis was based on the presence of oesophageal dysfunction, >15 eosinophils per high-power field, and a lack of response to proton pump inhibitors. Gastroesophageal reflux disease showed intraepithelial eosinophils, but a clinical and/or histological response to proton pump inhibitor therapy. We also evaluated an additional cohort of 22 cases with intraepithelial eosinophils. Immunohistochemical staining for IgG4 was performed. Sixteen of 21 (76%) eosinophilic oesophagitis cases showed intrasquamous extracellular IgG4 deposits, whereas all 25 gastroesophageal reflux disease cases were negative. Mucosal IgG4-positive plasma cells were identified in eosinophilic oesophagitis and gastroesophageal reflux disease cases in 58% and 40% of cases, respectively. Eosinophilic oesophagitis patients receiving treatment were less likely to be positive for intraepithelial IgG4 deposits (88% versus 53%). In the validation cohort, the sensitivity and specificity for eosinophilic oesophagitis were 88% and 100%, respectively.

CONCLUSIONS

The presence of intrasquamous IgG4 deposits is a useful adjunctive marker in the distinction between eosinophilic oesophagitis and gastroesophageal reflux disease.

Prospective assessment of the diagnostic utility of esophageal brushings in adults with eosinophilic esophagitis

Patients with eosinophilic esophagitis (EoE) undergo multiple endoscopies with biopsy for both diagnosis and assessment of treatment response, which is inconvenient and costly. Brush cytology has been examined in Barrett's esophagus to reduce the need for repeated endoscopic biopsies. The aim of this pilot study was to evaluate the ability of brush cytology to detect mucosal eosinophilia in patients with EoE. This prospective study included adults with untreated and treated esophageal eosinophilia undergoing endoscopy at a tertiary care center. Patients received paired brushings and biopsies at the proximal and distal esophagus. A blinded pathologist quantified the number of eosinophils and epithelial cells per high-power field (hpf) on the cytology slides. The ratio of eosinophils/epithelial cells was used to normalize the cytology specimens for density of cells collected. The main outcome measures were sensitivity and specificity of brush cytology, and correlation between cytology and histology. Twenty-eight patients enrolled. The average age of the cohort was 37.7 ± 10.4 years; 75% of subjects were male. The sensitivity of cytology was 67-69% at the proximal esophagus and 70-72% at the distal esophagus. The specificity was 61-67% proximally and 70-75% distally. Histology was not significantly correlated with the max ratio of eosinophils/epithelial cells per hpf or the absolute number of eosinophils on cytology slides. Cytology using esophageal brushing has limited sensitivity and specificity for the detection of esophageal mucosal eosinophilia. The presence of exudates on endoscopy increased the detection of eosinophilia, which could make cytology useful in pediatric EoE, which often has a more exudative presentation. Diagnostic yield may improve with alternative acquisition techniques or the incorporation of eosinophil degranulation proteins.

Evaluation of Histologic Cutpoints for Treatment Response in Eosinophilic Esophagitis

AIM

No consensus exists on the definition of successful treatment in eosinophilic esophagitis (EoE). The aim of this study was to identify the optimal histologic cutpoint to define successful treatment of EoE by assessing rates of symptomatic and endoscopic improvement.

MATERIALS AND METHODS

We performed a retrospective cohort study utilizing the University of North Carolina EoE Clinicopathologic Database between 2006 and 2013. Rates of symptomatic and endoscopic improvement were determined, as were post-treatment eosinophil counts. The area under the receiver operator characteristic curve (AUC) was calculated for symptomatic and endoscopic response at several possible eosinophil count cutpoints (eos/hpf). Predictors of response were also assessed.

RESULTS

Of 224 treatments in 199 patients, 76% were associated with symptomatic improvement, 68% with endoscopic improvement, and 60% with both. Of treatments that resulted in a post-treatment count of <15 eos/hpf, 90% were associated with an endoscopic response, 88% with a symptomatic response, and 81% with both symptomatic and endoscopic responses. Using a <15 eos/hpf threshold, the area under the curves (AUCs) were 0.70, 0.78, and 0.75 for symptomatic, endoscopic, and symptomatic/endoscopic responses, respectively. Lower histologic cut-points did not result in a substantial gain in response, but decreased the AUC.

CONCLUSION

In this large cohort of EoE patients, rates of symptomatic and endoscopic improvement were generally associated with histologic improvement. A histologic cutoff for treatment response of <15 eos/hpf may balance clinical outcomes and test performance.

Interactions between gastro-oesophageal reflux disease and eosinophilic oesophagitis

Gastro-oesophageal reflux disease (GORD) is the most common oesophageal disorder, whereas eosinophilic oesophagitis (EoE) is an emerging disease unresponsive to PPI therapy. Updated guidelines in 2011 described proton pump inhibitor-responsive esophageal eosinophilia (PPI-REE), a novel phenotype in EoE patients who were responsive to PPIs. This article aims to update the complex interplay between GORD, EoE and PPIs. Oesophageal mucosal integrity is diffusely impaired in EoE and PPI-REE patients. PPI-REE might occur with either normal or pathological pH monitoring. The genetic hallmark of EoE is overlapped in PPI-REE, but not in GORD. PPIs can partially restore epithelial integrity and reverse allergic inflammation gene expression in PPI-REE. Acid hypersensitivity in EoE patients may explain symptomatic but not histological response on PPIs. Unsolved issues with PPI-REE are whether oesophageal barrier impairment is the cause or the effect of oesophageal eosinophilia and whether PPIs primarily targets barrier integrity or oesophageal inflammation.

A Clinical Prediction Tool Identifies Cases of Eosinophilic Esophagitis Without Endoscopic Biopsy: A Prospective Study

OBJECTIVES

Eosinophilic esophagitis (EoE) is difficult to distinguish from gastroesophageal reflux (GERD) and other causes of dysphagia. We assessed the utility of a set of clinical and endoscopic features for predicting EoE without obtaining esophageal biopsies.

METHODS

We prospectively enrolled consecutive adults undergoing outpatient upper endoscopy at the University of North Carolina from July 2011 through December 2013. Incident cases of EoE were diagnosed per consensus guidelines. Non-EoE controls had either GERD- or dysphagia-predominant symptoms. A predictive model containing clinical and endoscopic, but no histological, data was assessed. Receiver operator characteristic curves were constructed and the area under the curve (AUC) was calculated.

RESULTS

A total of 81 EoE cases (mean age 38 years; 60% male; 93% white; 141 eosinophils per high-power field (eos/hpf)) and 144 controls (mean age 52, 38% male; 82% white; 3 eos/hpf) were enrolled. A combination of clinical (age, sex, dysphagia, food allergy) and endoscopic (rings, furrows, plaques, hiatal hernia) features was highly predictive of EoE. The AUC was 0.944, with sensitivity, specificity, and accuracy of 84, 97, and 92%. Similar values were seen after limiting controls to those with only reflux or dysphagia or to those with esophageal eosinophilia not due to EoE.

CONCLUSIONS

We validated a set of clinical and endoscopic features to predict EoE with a high degree of accuracy and allow identification of those at very low risk of disease. Use of these predictors at the point-of-care will avoid the effort and expense of low-yield histological examinations for EoE.

Extracellular Eosinophil Granule Protein Deposition in Ringed Esophagus with Sparse Eosinophils

BACKGROUND

Eosinophilic esophagitis (EoE) remains difficult to classify because of varying presentations. Not uncommonly, patients present with symptoms of esophageal dysfunction and have esophageal changes on endoscopy resembling EoE but without >15 eosinophils/HPF. Patients with low numbers of eosinophils in esophageal biopsy specimens may have esophageal changes and symptomatic disease brought about by eosinophil granule protein deposition without recognizable intact cells.

AIM

To determine whether extracellular eosinophil granule protein deposition is present in the esophagi of patients with low eosinophil numbers who have clinical symptoms and characteristic endoscopic esophageal changes of EoE including ringed esophagus (RE).

METHODS

Esophageal biopsy specimens were studied from eight EoE patients with >15 eosinophils per high power field (HPF) and nine patients with RE (<15 eosinophils/HPF). The specimens were analyzed for eosinophil granule proteins, major basic protein 1 (eMBP1) and eosinophil-derived neurotoxin (EDN), by indirect immunofluorescence.

RESULTS

Both EoE and RE showed positive EDN and eMBP1 extracellular deposition; control esophagus showed minimal or none. Comparing EoE and RE, extracellular EDN and eMBP1 were similar except that EDN in EoE was greater in the distal esophagus.

CONCLUSIONS

This study highlights the importance of assessing eosinophil granule protein deposition in esophageal disease with potential eosinophil involvement. Persistent/progressive esophageal changes may be brought about by eosinophil granule proteins despite low numbers of intact cells. The meaning of "resolution" in EoE may need to be redefined based on numbers of esophageal eosinophils, extracellular eosinophil granule protein deposition, and subsequent clinical course of patients.

Proton pump inhibitor-responsive oesophageal eosinophilia and eosinophilic oesophagitis: more similarities than differences

PURPOSE OF REVIEW

The purpose of this study is to discuss the clinical, endoscopic and histologic features, pathogenesis and disease mechanisms of proton pump inhibitor (PPI)-responsive oesophageal eosinophilia (PPI-REE), and to highlight similarities and differences with eosinophilic oesophagitis (EoE).

RECENT FINDINGS

PPI-REE is a condition in which patients have clinical and histologic findings similar to EoE, but achieve complete remission with PPI treatment. More than one-third of patients who have oesophageal symptoms associated with oesophageal eosinophilia respond to PPI treatment. Emerging data elucidating the pathogenesis of PPI-REE have shown that Th2-related inflammatory factors such as interleukin (IL)-13, IL-5, eotaxin-3 and major basic protein (MBP) are elevated in PPI-REE, similar to EoE. PPI-REE also shares a genetic expression signature with EoE that reverses with PPI treatment. Mechanisms proposed to explain the PPI response include an acid-independent, anti-inflammatory action of PPIs and PPI-induced restoration of oesophageal barrier function.

SUMMARY

Multiple features of PPI-REE overlap extensively with EoE. This raises the question of whether PPI-REE is merely a subtype of EoE rather than an independent condition. This similarity may have future implications for algorithms informing evaluation and treatment of oesophageal eosinophilia.

Comparison of eotaxin-3 biomarker in patients with eosinophilic oesophagitis, proton pump inhibitor-responsive oesophageal eosinophilia and gastro-oesophageal reflux disease

BACKGROUND

Proton pump inhibitor-responsive oesophageal eosinophilia (PPI-REE) is a recently described entity which resembles oeosinophilic oesophagitis (EoE), yet responds to acid suppressive treatment.

AIM

To determine whether EoE shares similar staining features with PPI-REE or with gastro-oesophageal reflux disease (GERD).

METHODS

This retrospective study consisted of patients with an established diagnosis of EoE, PPI-REE, or GERD identified from a database during a 1-year period. Immunohistochemistry (IHC) analysis was performed specifically targeting eotaxin-3 antibodies. All sections were qualitatively (intensity) and quantitatively (percentage of cells stained) assessed independently by two blinded pathologists.

RESULTS

The cohort consisted of three groups of patients: EoE (n = 22), PPI-REE (n = 23) and GERD (n = 23) for a total of 68 patients. Study demographics included mean age 39 (14) years, 75% male and 77% Caucasian. There was a significant difference in the eotaxin-3 staining among EoE, PPI-REE and GERD groups [mean score (s.d.): 1.2 (1.2), 0.8 (1.0), 0.3 (0.7), P = 0.006]. Staining scores of EoE patients were significantly higher compared with GERD (P = 0.002) and a trend towards significance was seen between EoE and PPI-REE (P = 0.054). There was also a significant difference in EoE staining intensity score among the three groups (P = 0.006). Intensity scores of EoE were significantly higher compared with GERD [1.0 (0.9) vs. 0.22 (0.52), P < 0.001]. There was no significant difference between EoE and PPI-REE groups [1.0 (0.0) vs. 0.52 (0.75) P = 0.094].

CONCLUSIONS

A difference in eotaxin-3 staining was seen in the three groups of patients with oesophageal eosinophilia. Eotaxin-3 can distinguish EoE from GERD, but not from proton pump inhibitor responsive-oesophageal eosinophilia.

Utility of a Noninvasive Serum Biomarker Panel for Diagnosis and Monitoring of Eosinophilic Esophagitis: A Prospective Study

OBJECTIVES

Noninvasive biomarkers would be valuable for diagnosis and monitoring of eosinophilic esophagitis (EoE). The aim of this study was to determine the utility of a panel of serum biomarkers for the diagnosis and management of EoE.

METHODS

We conducted a prospective cohort study of consecutive adults undergoing outpatient esophagogastroduodenoscopy. Incident cases of EoE were diagnosed per consensus guidelines; controls had gastroesophageal reflux disease (GERD) or dysphagia and did not meet the EoE criteria. EoE cases were treated with topical steroids and had repeat endoscopy. Pre- and post-treatment serum samples were analyzed in a blinded manner for interleukin (IL)-4, IL-5, IL-6, IL-9, IL-13, transforming growth factor (TGF)-α, TGF-β, tumor necrosis factor-α, eotaxin-1, -2, and -3, thymic stromal lymphopoietin (TSLP), major basic protein, and eosinophil-derived neurotoxin. Cases and controls were compared at baseline, and pre- and post-treatment assays were compared in cases.

RESULTS

A total of 61 incident EoE cases and 87 controls were enrolled; 51 EoE cases had post-treatment serum analyzed. There were no significant differences in any of the biomarkers between EoE cases and controls at baseline. IL-13 and eotaxin-3 for cases and controls were 85 ± 160 vs. 43 ± 161 pg/ml (P=0.12) and 41 ± 159 vs. 21 ± 73 (P=0.30). There were no significant differences in assay values among cases before and after treatment. There were also no differences after stratification by atopic status or treatment response.

CONCLUSIONS

A panel of inflammatory factors known to be associated with EoE pathogenesis were not increased in the serum, nor were they responsive to therapy. None of these biomarkers are likely candidates for a serum test for EoE. Histologic analysis for diagnosis and management of EoE continues to be necessary, and novel, less invasive, biomarkers are needed.

Esophagitis: Old Histologic Concepts and New Thoughts

Context

Inflammatory lesions of the esophagus are a diverse group, often with nonspecific histologic findings. These benign changes can produce diagnostic difficulties for pathologists.

Objective

To discuss the typical histologic findings of a variety of the most common causes of esophagitis (reflux, eosinophilic esophagitis, infections, medications) along with less common issues such as sloughing esophagitis and skin disorders involving the squamous mucosa.

Data Sources

The literature has been reviewed to discuss histologic definitions of current and developing issues in the area of esophagitis.

Conclusions

Histologic features are not entirely sensitive and specific for inflammatory esophageal disorders. Awareness of these problems is essential; clinical and endoscopic information can be very useful in distinguishing among the various lesions.

Eosinophilic Laryngitis in Children with Aerodigestive Dysfunction

Objective

To describe the presence of laryngeal eosinophils and associated symptomatology in patients with aerodigestive dysfunction.

Study Design

Case series with chart review.

Setting

Single tertiary pediatric referral center.

Subjects

Eighty-one consecutive pediatric patients referred to a multidisciplinary aerodigestive clinic with upper airway concerns.

Methods

Microlaryngoscopy and posterior arytenoid biopsy, flexible bronchoscopy, esophagogastroduodenoscopy and esophageal biopsy, and impedance probe testing were performed as indicated by clinical symptoms. Positive versus negative posterior arytenoid biopsy for eosinophils and the presence or absence of concomitant histopathological laryngitis and/or esophagitis were measured.

Results

Nine of 81 (11%) patients had positive laryngeal biopsy for eosinophils (range, 1-29 eosinophils/high-powered field [HPF]). Three of these 9 patients also had concurrent biopsy-proven eosinophilic esophagitis, while 8 of 81 total patients had biopsy-proven eosinophilic esophagitis. The frequency of biopsy-proven eosinophilic esophagitis was higher in patients with posterior arytenoid eosinophils versus patients without laryngeal eosinophils (33% versus 6.9%, P = .0408).

Conclusions

Eosinophilic inflammation in the larynx has not been described in children with complex aerodigestive complaints. Posterior arytenoid eosinophils may serve as a marker of chronic laryngeal inflammation in children with aerodigestive dysfunction, although their exact role in this inflammation remains unclear. In our population, >15 eosinophils/HPF within posterior arytenoid biopsies was associated with concomitant eosinophilic esophagitis.

Non-invasive ultrasound to identify eosinophil granule proteins in eosinophilic esophagitis

Although traditional microbubble contrast agents are bright, the high contrast of gas bubbles and air-water interfaces in the upper gastrointestinal tract renders these agents less useful for diagnosing diseases such as eosinophilic esophagitis, a disease characterized by patchy infiltration of eosinophils into the esophagus. Here we report a first-in-class ultrasound contrast enhancement agent composed of echogenic insulin particles, which are labeled with molecular recognition elements to diagnose eosinophil-associated diseases. We prepared solid echogenic insulin particles, tethered antibodies to eosinophil granule major basic protein 1 (MBP-1) to their surfaces and experimentally evaluated binding of these agents to MBP-1 on ex vivo non-human primate esophagi. We found that insulin particles can be readily observed by ultrasound and bind to MBP-1-coated esophagi within minutes. Our results suggest the potential of this new class of solid contrast agents to image, diagnose and improve management of eosinophilic esophagitis.

Predictors of response to steroid therapy for eosinophilic esophagitis and treatment of steroid-refractory patients

BACKGROUND & AIMS

Eosinophilic esophagitis (EoE) is commonly treated with swallowed (topical) corticosteroids (tCS). However, few factors have been described that predict outcomes of steroid therapy. We aimed to identify factors associated with nonresponse to tCS and report outcomes of second-line treatment for patients with steroid-refractory EoE.

METHODS

We performed a retrospective cohort study by using the University of North Carolina EoE Clinicopathologic Database to identify patients who received tCS for EoE from 2006 through 2013. Demographic, symptom, endoscopic, and histologic data were extracted from medical records. Immunohistochemistry was performed on archived biopsies. Responders and nonresponders to tCS were compared.

RESULTS

Of 221 patients with EoE who received tCS, 71% had endoscopic improvement, 79% had symptomatic improvement, and 57% had histologic response (<15 eosinophils/high-power field). After multivariate logistic regression, esophageal dilation at the baseline examination predicted nonresponse (odds ratio, 2.9; 95% confidence interval, 1.4-6.3), and abdominal pain predicted response (odds ratio for nonresponse, 0.31; 95% confidence interval, 0.12-0.83); no other clinical features were predictive. On the basis of immunohistochemical analysis, higher baseline levels of tryptase (244 vs 157 mast cells/mm(2), P = .04) and eotaxin-3 (2425 vs 239 cells/mm(2), P = .02) were associated with steroid response, but levels of major basic protein were not. Among 27 steroid-refractory patients, a mean of 2 additional therapies were tried; only 48% of the patients eventually responded to any second-line therapy.

CONCLUSIONS

On the basis of a retrospective analysis of a large group of patients with EoE, only 57% have a histologic response to steroid therapy. Baseline esophageal dilation and decreased levels of mast cells and eotaxin-3 predicted which patients would not respond to therapy. Combining clinical factors and immunohistochemistry might therefore be used to direct therapy.

Translating new developments in eosinophilic esophagitis pathogenesis into clinical practice

OPINION STATEMENT

New developments in eosinophilic esophagitis (EoE) pathogenesis are shaping our current therapeutic and management strategies. EoE is a chronic allergic inflammatory disease with progression to fibrostenotic disease. The disease warrants early diagnosis and long-term maintenance therapy. The diagnosis of EoE should be based on the concept of an allergy-mediated disease with esophageal dysfunction and esophageal eosinophilia. Recent findings suggest that proton pump inhibitor (PPI)-responsive esophageal eosinophilia (PPI-REE) is likely a continuum of EoE or a similar T-helper 2 (Th2)-mediated allergic process. PPIs have therapeutic properties that can benefit both gastroesophageal reflux disease (GERD) and EoE. Therefore, PPIs should be considered not a diagnostic tool but, rather, a therapeutic option for EoE. If patients are PPI nonresponsive, then dietary therapy or steroid therapy should be considered. Dilation can be reserved as adjuvant therapy for severe fibrostenotic lesions.

Markers of eosinophilic inflammation for diagnosis of eosinophilic esophagitis and proton pump inhibitor-responsive esophageal eosinophilia: a prospective study

BACKGROUND & AIMS

Distinguishing between eosinophilic esophagitis (EoE), gastroesophageal reflux disease, and proton pump inhibitor-responsive esophageal eosinophilia (PPI-REE) is challenging. We assessed whether immunohistochemical analysis of esophageal tissues for major basic protein (MBP), eotaxin-3, and tryptase can be used for diagnosis of EoE and to differentiate EoE from PPI-REE.

METHODS

We conducted a prospective study of 196 consecutive adults who underwent outpatient endoscopy at the University of North Carolina from 2009 through 2012. Incident cases of EoE were diagnosed per consensus guidelines. Patients with gastroesophageal reflux disease or dysphagia served as controls. PPI-REE was defined as a symptomatic and histologic response to a PPI. Immunohistochemistry was performed to quantify MBP, eotaxin-3, and tryptase. The maximum density of epithelial staining was determined for each assay; levels were compared between EoE and control groups and then EoE and PPI-REE groups, and receiver operating characteristic curves were constructed.

RESULTS

Esophageal tissues from patients with EoE (n = 50) had a median 951 MBP-positive cells/mm(2), whereas those from controls (n = 123) had a median 2 MBP-positive cells/mm(2) (P < .001). Samples from patients with EoE had a median 155 eotaxin-3-positive cells/mm(2), and those from controls (n = 123) had 18 eotaxin-3-positive cells/mm(2) (P < .001). Samples from patients with EoE had a median 249 tryptase-positive cells/mm(2), and those from controls (n = 123) had 11 tryptase-positive cells/mm(2) (P < .001). Levels of MBP, eotaxin-3, tryptase, and the combination of all 3 identified patients with EoE with area under the receiver operating characteristic curve values of 0.99, 0.94, 0.99, and 1.00. Analyses of only samples with eosinophil counts of 10-100 eosinophils per high-power field produced similar results. No marker distinguished EoE from PPI-REE. Esophageal tissues from patients with PPI-REE (n = 23) had 987 MBP-positive cells/mm(2) (P = .18, compared with EoE), 160 eotaxin-3-positive cells/mm(2) (P = .33), and 243 tryptase-positive cells/mm(2) (P = .28).

CONCLUSIONS

Esophageal tissues from patients with EoE have substantially higher levels of MBP, eotaxin-3, and tryptase than controls on the basis of immunohistochemical analysis. Assays for the 3 markers identify patients with EoE with 100% accuracy but cannot distinguish EoE from PPI-REE.

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.

Administrative coding is specific, but not sensitive, for identifying eosinophilic esophagitis

The use of administrative databases to conduct population-based studies of eosinophilic esophagitis (EoE) in the United States is limited because it is unknown whether the International Classification of Diseases, Ninth Revision (ICD-9) code for EoE, 530.13, accurately identifies those who truly have the disease. The aim of this retrospective study was to validate the ICD-9 code for identifying cases of EoE in administrative data. Confirmed cases of EoE as per consensus guidelines (symptoms of esophageal dysfunction and ≥15 eosinophils per high-power field on biopsy after 8 weeks of twice daily proton pump inhibitor therapy) were identified in the University of North Carolina (UNC) EoE Clinicopathologic Database from 2008 to 2010; 2008 was the first year in which the 530.13 code was approved. Using the Carolina Data Warehouse, the administrative database for patients seen in the UNC system, all diagnostic and procedure codes were obtained for these cases. Then, with the EoE cases as the reference standard, we re-queried the Carolina Data Warehouse over the same time frame for all patients seen in the system (n=308,372) and calculated the sensitivity and specificity of the ICD-9 code 530.13 as a case definition of EoE. To attempt to refine the case definition, we added procedural codes in an iterative fashion to optimize sensitivity and specificity, and restricted our analysis to privately insured patients. We also conducted a sensitivity analysis with 2011 data to identify trends in the operating parameters of the code. We identified 226 cases of EoE at UNC to serve as the reference standard. The ICD-9 code 530.13 yielded a sensitivity of 37% (83/226; 95% confidence interval: 31-43%) and specificity of 99% (308,111/308,146; 95% confidence interval: 98-100%). These operating parameters were not substantially altered if the case definition required a procedure code for endoscopy or if cases were limited to those with commercial insurance. However, in 2011, the sensitivity of the code had increased to 61%, while the specificity remained at 99%. The ICD-9 code for EoE, 530.13, had excellent specificity for identifying cases of EoE in administrative data, although this high specificity was achieved at an academic center. Additionally, the sensitivity of the code appears to be increasing over time, and the threshold at which it will stabilize is not known. While use of this administrative code will still miss a number of cases, those identified in this manner are highly likely to have the disease.

Histologic eosinophilic gastritis is a systemic disorder associated with blood and extragastric eosinophilia, TH2 immunity, and a unique gastric transcriptome

BACKGROUND

The definition of eosinophilic gastritis (EG) is currently limited to histologic EG based on the tissue eosinophil count.

OBJECTIVE

We aimed to provide additional fundamental information about the molecular, histopathologic, and clinical characteristics of EG.

METHODS

Genome-wide transcript profiles and histologic features of gastric biopsy specimens, as well as blood eosinophil counts, were analyzed in patients with EG and control subjects (n = 15 each).

RESULTS

The peak gastric antrum eosinophil count was 283 ± 164 eosinophils/×400 high-power field in patients with EG and 11 ± 9 eosinophils/×400 high-power field in control subjects (P = 6.1 × 10(-7)). Patients with EG (87%) had coexisting eosinophilic inflammation in multiple gastrointestinal segments; the esophagus represented the most common secondary site. Increased peripheral blood eosinophil counts (patients with EG: 1.09 ± 0.88 × 10(3)/μL vs control subjects: 0.09 ± 0.08 10(3)/μL, P = .0027) positively correlated with peak gastric eosinophil counts (Pearson r(2) = .8102, P < .0001). MIB-1(+) (proliferating), CD117(+) (mast cells), and FOXP3(+) (regulatory T cells, activated T cells, or both) cell counts were increased in patients with EG. Transcript profiling revealed changes in 8% of the genome in gastric tissue from patients with EG. Only 7% of this EG transcriptome overlapped with the eosinophilic esophagitis transcriptome. Significantly increased IL4, IL5, IL13, IL17, CCL26, and mast cell-specific transcripts and decreased IL33 transcripts were observed.

CONCLUSION

EG is a systemic disorder involving profound blood and gastrointestinal tract eosinophilia, TH2 immunity, and a conserved gastric transcriptome markedly distinct from the eosinophilic esophagitis transcriptome. The data herein define germane cellular and molecular pathways of EG and provide a basis for improving diagnosis and treatment.

Which patients with eosinophilic esophagitis (EoE) should receive elemental diets versus other therapies?

Eosinophilic esophagitis (EoE) has increasingly been identified in both children and adults. The aim of therapies is to alleviate symptoms while reducing the esophageal inflammation. Mechanical dilation is effective at relieving symptoms, but without the benefit of controlling disease inflammation. Topical steroids appear to be effective at controlling both symptoms and esophageal eosinophilia. Recurrence rates are high once steroids are discontinued. For dietary modification, both the elimination of select, specific foods and the complete elimination of food proteins via amino acid formulas have been looked at. Both forms of dietary modification are effective. Elemental diet, although not an ideal first-line therapy for EoE, provides insight into the etiology of unusual or refractory EoE. The contribution of unusual food antigens to EoE may be determined via the use of amino-acid-based formulas in patients with EoE.

Dietary elimination therapy is an effective option for adults with eosinophilic esophagitis

BACKGROUND & AIMS

Eosinophilic esophagitis (EoE) is an immune-mediated disorder. Food elimination is an established treatment for children, but data in adults are limited. We aimed to determine the response of adults with EoE to dietary therapy.

METHODS

This was a retrospective cohort study using the University of North Carolina EoE database from 2006 to 2012. Subjects were age 18 and older, had EoE by consensus guidelines, and had undergone dietary therapy either with a targeted elimination diet or a 6-food elimination diet (SFED). Outcomes were symptomatic, endoscopic, and histologic improvement. Demographic, endoscopic, symptomatic, and laboratory predictors of response to dietary therapy were assessed.

RESULTS

Of 31 adults who underwent dietary therapy (mean age, 36 y; 48% male; 90% white; mean baseline eosinophil count, 78 eos/hpf), 22 had a targeted elimination diet and 9 had SFED. Symptoms improved in 71% (68% in targeted, 78% in SFED), and endoscopic appearance improved in 54% (53% in targeted, 56% in SFED). After dietary therapy, the mean eosinophil count decreased to 43 eos/hpf (P = .009). Eleven subjects (39%) responded with fewer than 15 eos/hpf (32% in targeted and 56% in SFED; P = .41). No clinical, endoscopic, or histologic factors predicted response to dietary therapy. Of the 11 responders, 9 underwent food re-introduction to identify trigger(s), and 4 (44%) reacted to dairy, 4 (44%) reacted to eggs, 2 (22%) reacted to wheat, 1 (11%) reacted to shellfish, 1 (11%) reacted to legumes, and 1 (11%) reacted to nuts.

CONCLUSIONS

Dietary elimination is a successful treatment modality for adults with EoE. Further research should emphasize which factors can predict effective dietary therapy.