Longitudinal Evaluation of Noninvasive Biomarkers for Eosinophilic Esophagitis

Biomarkers for a less invasive strategy to predict children with eosinophilic esophagitis

BACKGROUND

Noninvasive biomarkers for diagnosing and monitoring eosinophilic esophagitis (EoE) are currently lacking. This study evaluates 20 biomarkers in serum and saliva, aiming to assess their diagnostic potential in pediatric EoE patients and healthy individuals.

METHODS

Blood and saliva from children undergoing upper endoscopy were analyzed for biomarkers, including absolute eosinophil count (AEC), eosinophil-derived neurotoxin (EDN), total and specific IgG4-antibodies (sIgG4), specific IgE-antibodies (sIgE) and 15-hydroxyeicosatetraenoic acid (15(S)-HETE). Some patients participated twice, forming a longitudinal cohort. The ability to use the biomarkers to predict the EoE diagnosis was evaluated.

RESULTS

Analysis from 105 children divided into active EoE, remission, and healthy, revealed elevated levels of serum biomarkers (AEC, EDN, 15(S)-HETE, sIgG4, and sIgE) in active EoE compared to healthy individuals. A combination of biomarkers (AEC, EDN, sIgE to egg white and wheat) and symptoms showed an AUC of 0.92 in distinguishing between the three groups. We further showed that optimal cutoff values for these biomarkers could discriminate between active EoE and healthy with a sensitivity of 88% and a specificity of 100% in distinguishing EoE (active and in remission) from healthy. Longitudinally, levels of EDN, sIgG4 to Bos d 4, Bos d 5, Bos d 8, gliadin, and birch, and sIgE to milk decreased in patients progressing from active EoE to remission (p <.05).

CONCLUSIONS

This study identified novel biomarkers associated with EoE and proposes a panel, together with symptoms, for effective discrimination between active EoE, EoE in remission, and healthy individuals. The findings may contribute to a less invasive diagnostic method and may be a potential surveillance tool for pediatric EoE patients.

Noninvasive Disease Assessment in Eosinophilic Esophagitis With Fractionated Exhaled Nitric Oxide, Blood, and Fecal Biomarkers

BACKGROUND

Eosinophilic Esophagitis (EoE) is a chronic inflammatory condition of the esophagus triggered by food and aeroallergens. There is a need for noninvasive biomarkers that reliably detect EoE in patients with cardinal symptoms and predict treatment response to reduce endoscopic evaluations.

STUDY

Nonasthmatic patients 18 years or above with suspected or diagnosed EoE, gastroesophageal reflux disease (GERD), and control individuals with indication for endoscopy were enrolled prospectively between November 2020 and May 2022. Participants underwent body plethysmography with fractionated exhaled nitric oxide (FeNO) level measurement. Besides, serum and fecal biomarkers were measured by ELISA. A follow-up examination was scheduled after treatment initiation in patients with active EoE.

RESULTS

The median FeNO level in active EoE (20 ppb) was higher compared with GERD (15 ppb, P=0.038) and control individuals (14 ppb, P=0.046). Median FeNO did not significantly differ in EoE patients who underwent follow-up assessment after treatment response (20 ppb vs. 18 ppb, P=0.771). Serum EDN, ECP, and the absolute eosinophil blood count (AEC) were elevated in active EoE compared with control individuals but not compared with GERD except for AEC. Serum EDN, ECP and AEC decreased in EoE in remission at follow-up assessment. None of the fecal biomarkers was elevated in active EoE or during treatment.

CONCLUSIONS

Assessment of FeNO may have diagnostic value in differentiating patients with active EoE from non-EoE patients but is not a suitable marker for monitoring disease activity. Serum EDN, ECP, TARC, and AEC levels are emerging as potential candidates for monitoring disease activity in EoE.

Diagnosis and management of eosinophilic esophagitis in children: An update from the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN)

INTRODUCTION

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease of the esophagus characterized by symptoms of esophageal dysfunction and histologically by predominantly eosinophilic infiltration of the squamous epithelium. European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) published a guideline in 2014; however, the rapid evolution of knowledge about pathophysiology, diagnostic criteria, and therapeutic options have made an update necessary.

METHODS

A consensus group of pediatric gastroenterologists from the ESPGHAN Working Group on Eosinophilic Gastrointestinal Diseases (ESPGHAN EGID WG) reviewed the recent literature and proposed statements and recommendations on 28 relevant questions about EoE. A comprehensive electronic literature search was performed in MEDLINE, EMBASE, and Cochrane databases from 2014 to 2022. The Grading of Recommendations Assessment, Development and Evaluation system was used to assess the quality of evidence and formulate recommendations.

RESULTS

A total of 52 statements based on the available evidence and 44 consensus-based recommendations are available. A revision of the diagnostic protocol, options for initial drug treatment, and the new concept of simplified empiric elimination diets are now available. Biologics are becoming a part of the potential armamentarium for refractory EoE, and systemic steroids may be considered as the initial treatment for esophageal strictures before esophageal dilation. The importance and assessment of quality of life and a planned transition to adult medical care are new areas addressed in this guideline.

CONCLUSION

Research in recent years has led to a better understanding of childhood EoE. This guideline incorporates the new findings and provides a practical guide for clinicians treating children diagnosed with EoE.

Baseline Peripheral Eosinophil Count Independently Predicts Proton Pump Inhibitor Response in Eosinophilic Esophagitis

GOALS

To assess the predictive value of baseline peripheral absolute eosinophil counts (AECs) for proton pump inhibitor (PPI) response in eosinophilic esophagitis (EoE).

BACKGROUND

PPI leads to histologic remission in ~50% of EoE patients, although there are few distinguishing clinical features between PPI-responsive (PPI-r-EoE) and nonresponsive (PPI-nr-EoE) diseases. Peripheral eosinophilia is present in ~50% of EoE cases and is associated with eosinophil density on esophageal biopsy and worse clinical outcomes. The association between peripheral eosinophilia and PPI-responsiveness in EoE remains unclear.

STUDY

This is a retrospective cohort study of adult EoE patients at a tertiary center between 2012 and 2016. All patients underwent twice daily PPI trials for ≥8 weeks followed by repeat esophageal biopsies and were classified as PPI-r-EoE or PPI-nr-EoE based on histologic response (<15 eosinophils/high power field). Baseline peripheral AEC was obtained within 1 month before index endoscopy. Analyses were performed using Fisher exact/Student t test (univariate) and logistic regression (multivariable).

RESULTS

One hundred eighty-three patients (91 PPI-nr-EoE and 92 PPI-r-EoE) were included. Mean peripheral AEC was higher among PPI-nr-EoE patients (0.41 vs 0.24 K/µL, P = 0.013). Baseline peripheral eosinophilia (>0.5 K/µL) was more prevalent among patients with PPI-nr-EoE (70.4% vs 45.5%, P = 0.023) and a history of food impaction (51.9% vs 23.7%, P = 0.0082). On multivariable analyses, peripheral eosinophilia remained an independent predictor for PPI response (adjacent odds ratio = 2.86, CI: 1.07-7.62, P = 0.036) and food impaction (adjacent odds ratio = 2.80, CI: 1.07-7.35, P = 0.037).

CONCLUSIONS

Baseline peripheral eosinophilia independently predicts PPI nonresponse and food impaction in EoE patients. Peripheral AEC may help therapy selection in EoE and prevent delays in achieving histologic remission.

Eosinophilic esophagitis: does age matter?

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Blood-Based Biomarkers for Eosinophilic Esophagitis and Concomitant Atopic Diseases: A Look into the Potential of Extracellular Vesicles

Eosinophilic esophagitis (EoE) is a chronic, Th2-inflammatory disease of the esophagus that can severely affect food intake. Currently, diagnosis and assessing response to treatment of EoE is highly invasive and requires endoscopy with esophageal biopsies. Finding non-invasive and accurate biomarkers is important for improving patient well-being. Unfortunately, EoE is usually accompanied by other atopies, which make it difficult to identify specific biomarkers. Providing an update of circulating EoE biomarkers and concomitant atopies is therefore timely. This review summarizes the current knowledge in EoE blood biomarkers and two of its most common comorbidities, bronchial asthma (BA) and atopic dermatitis (AD), focusing on dysregulated proteins, metabolites, and RNAs. It also revises the current knowledge on extracellular vesicles (EVs) as non-invasive biomarkers for BA and AD, and concludes with the potential use of EVs as biomarkers in 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.

Noninvasive biomarkers identify eosinophilic esophagitis: A prospective longitudinal study in children

BACKGROUND

Esophageal histology is critical for diagnosis and surveillance of disease activity in eosinophilic esophagitis (EoE). A validated noninvasive biomarker has not been identified. We aimed to determine the utility of blood and urine eosinophil-associated proteins to diagnose EoE and predict esophageal eosinophilia.

METHODS

Blood and urine were collected from children undergoing endoscopy with biopsy. Absolute eosinophil count (AEC), plasma eosinophil-derived neurotoxin (EDN), eosinophil cationic protein (ECP), major basic protein-1 (MBP-1), galectin-10 (CLC/GAL-10), Eotaxin-2 and Eotaxin-3, and urine osteopontin (OPN) and matrix metalloproteinase-9 (MMP-9) were determined. Differences were assessed between EoE and control, and with treatment response. The capacity to predict EoE diagnosis and esophageal eosinophil counts was assessed.

RESULTS

Of 183 specimens were collected from 56 EoE patients and 15 non-EoE controls with symptoms of esophageal dysfunction; 33 EoE patients had paired pre- and post-treatment specimens. Plasma (CLC/GAL-10, ECP, EDN, Eotaxin-3, MBP-1) and urine (OPN) biomarkers were increased in EoE compared to control. A panel comprising CLC/GAL-10, Eotaxin-3, ECP, EDN, MBP-1, and AEC was superior to AEC alone in distinguishing EoE from control. AEC, CLC/GAL-10, ECP, and MBP-1 were significantly decreased in patients with esophageal eosinophil counts <15/hpf in response to treatment. AEC, CLC/GAL-10, ECP, EDN, OPN, and MBP-1 each predicted esophageal eosinophil counts utilizing mixed models controlled for age, gender, treatment, and atopy; AEC combined with MBP-1 best predicted the counts.

CONCLUSIONS

We identified novel panels of eosinophil-associated proteins that along with AEC are superior to AEC alone in distinguishing EoE from controls and predicting esophageal eosinophil counts.

An Update on Eosinophilic Esophagitis: Etiological Factors, Coexisting Diseases, and Complications

BACKGROUND

Eosinophilic esophagitis (EoE) is an immune-mediated clinicopathological condition characterized by esophageal infiltration with eosinophils resulting in chronic inflammation and stricture.

SUMMARY

The recent increase in the incidence of EoE and the characteristic presentation of symptoms with difficulty swallowing and food bolus impaction has raised key concerns of clinicians as well as researchers. EoE often presents with dysphagia, food impaction, nausea, regurgitation or vomiting, and decreased appetite. It is more common in males, affecting both adults and children. The causative manner of this condition is complex and multifactorial. Throughout recent years, researchers have made a significant contribution to understanding the pathogenesis of EoE, genetic background, natural history, work on allergy, and standardization in the evaluation of disease activity. There is relatively high prevalence of EoE among the population, emphasizing the importance of this disease. Key messages: Esophageal involvement with eosinophils may be manifested as isolated or with coexisting conditions and should be taken into consideration in the differential diagnosis. This study aimed to provide gastroenterologists with novel insights into the evaluation of esophageal involvement with eosinophils and to pay special attention to the etiological factors, coexisting clinical diseases, and complications.

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.

Blood mRNA levels of T cells and IgE receptors are novel non-invasive biomarkers for eosinophilic esophagitis (EoE)

Eosinophilic esophagitis (EoE) is often misdiagnosed as GERD; therefore, the goal of the current study is to establish a non-invasive diagnostic and monitoring biomarker that differentiated GERD from EoE. Reports indicates that IL-15 responsive iNKT cells and tissue specific IgE have a critical in EoE pathogenesis, not in GERD. Therefore, we tested the hypothesis that the panel of IL-15-responsive T cell and IgE receptors may be novel non-invasive biomarkers for EoE. Accordingly, the receptors of IL-15 responsive T cells (Vα24, Jα18, γδT, αβT) and IgE (FcεRI & FcεRII) were examined. The data indicates that blood mRNA levels of Vα24, Jα18, γδ T, αβ T and FcεRI are significantly reduced in EoE compared to the GERD patients and normal individuals. The ROC curve analysis indicated FcεRII, Jα18 and δ TCR are the positive predictors that discriminate EoE from GERD. Thus, these molecules will be a novel non-invasive diagnostic biomarker for EoE.

Treatment of eosinophlic esophagitis with swallowed topical corticosteroids

Eosinophilic esophagitis (EoE) is an emerging chronic local immune-mediated disease of the esophagus. Beside proton pump inhibitors and food-restriction-diets swallowed topical corticosteroids (STC) can be offered as a first line therapy according to current guidelines. This review describes the background and practical management of STCs in EoE. So far, mainly asthma inhalers containing either budesonide or fluticasone have been administered to the esophagus by swallowing these medications “off label”. Recently esophagus-targeted formulations of topical steroids have been developed showing clinicopathological response rates up to 85% - an orodispersible tablet of budesonide has been approved as the first “in label” medication for EoE in Europe in June 2018. Whereas it was shown that disease remission induction of EoE by STCs is highly effective, there is still a lack of data regarding long-term and maintenance therapy. However, current studies on STC maintenance therapy add some movement into the game.

Eosinophilic Esophagitis: Update on Diagnosis and Treatment in Pediatric Patients

Eosinophilic esophagitis (EoE) is a chronic immune-mediated inflammatory disorder characterized by symptomatic esophageal dysfunction and an eosinophil-predominant inflammation of the esophagus. EoE arises from interaction between genetic and environmental factors. In pediatric patients, clinical manifestations vary depending on age, from a gastroesophageal reflux disease (GERD)-like condition to severe dysphagic symptoms. Upper endoscopy is considered the gold standard for diagnosis and monitoring of EoE; however, significant efforts are underway to identify noninvasive diagnostic tools and biomarkers to avoid repetitive invasive procedures. Therapeutic first-line options currently available for EoE are elimination diets, proton pump inhibitors (PPIs), and steroids. The aim of treatment is to improve clinical symptoms while obtaining mucosal healing and avoiding long-term complications. Dietary treatment options comprise different empiric diets or an exclusively amino acid formula. Despite the efficacy of diets, compliance is often challenging. PPIs and topical steroids represent the main pharmacological options for EoE, and both can induce and maintain remission. Topical steroids have been reported as more effective, but data on long-term safety remain insufficient for both these and PPIs. Endoscopic dilations are currently reserved for severe untreated fibrostenotic disease unresponsive to medical therapies. Several biologic agents are available but not yet approved for EoE.

Proton Pump Inhibitors in Children: the Good, the Bad, and the Ugly

PURPOSE OF REVIEW

The evidence supporting or contesting the prescription of proton pump inhibitors (PPIs) for children and updates on side effects are reviewed.

RECENT FINDINGS

PPIs remain an important therapeutic option for esophagitis and gastritis. However, recent studies demonstrate no benefit when prescribing PPIs for chronic cough, infantile reflux, asthma, or functional gastrointestinal disorders. Recent studies suggest adverse effects on microbiome diversity and immune function, resulting in increased rates of gastrointestinal infections, bone fractures, and atopic disorders. PPIs influence a variety of cell types within the in the innate and adaptive immune systems. PPI prescriptions in children may be indicated for select conditions; however, multiple side effects and immune effects have been described. While most of these side effects are rare and mild, some studies suggest enduring adverse effects. Future studies to elucidate the mechanism behind some of these immune and infectious complications will be beneficial.

Do Histological Features of Eosinophilic Esophagitis in Children Correlate With Peripheral Eosinophils?

AIM

Eosinophilic esophagitis (EoE) is a chronic, relapsing inflammatory disease of the esophagus. We investigate whether peripheral eosinophils can be a good indicator of esophageal eosinophilia and whether they correlate with histological findings, such as basilar hyperplasia, spongiosis, microabscesses, number of lymphocytes, and number of neutrophils.

METHODS

A retrospective chart review was conducted with EoE patients ages <18 years after obtaining IRB approval. Biopsies obtained from 57 EoE patients were analyzed. Patient demographics, symptoms; complete blood count with differentials obtained at the time of endoscopies or within a month of the procedure, were documented.

RESULTS

A significant correlation was observed between peripheral absolute eosinophil count (AEC) and peak esophageal eosinophil count (P value: 0.0009). Subjects with biopsies suggestive of ongoing disease activity or active status had a higher mean of AEC at 577.41 ± 202.60 compared with subjects with inactivity with mean of 305.26 ± 526.67. However, when the subjects were broadly divided with 500 AEC as a cut off (<500 and >500 AEC), it was found that, out of 27 EoE inactive patients, 24 had AEC count less than or equal to 500 and out of 66 EoE active patients, 32 had AEC more than 500.

CONCLUSION

Active EoE status meant a higher mean of AEC compared with inactive status; but AEC was not found to be a sensitive tool for detecting active EoE.

Eosinophilic Esophagitis in Adults: A Concise Overview of an Evolving Disease

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease that encompasses esophageal symptoms along with eosinophilic infiltration of the esophageal epithelium. EoE is an evolving disease that has been a subject of interest to many researchers since the first studies recognized this condition as a new and distinct clinicopathological entity 25 years ago. Clinical presentation in adult patients may include dysphagia, food impaction, vomiting, and reflux symptoms. The diagnosis of EoE is based on the combination of clinical history suggestive of esophageal dysfunction, endoscopic features indicative of the disease, and histology revealing eosinophilic infiltration of the esophageal epithelium that persists after a trial of proton pump inhibitor therapy along with the exclusion of other disorders that may be associated with esophageal tissue eosinophilia. The interplay between EoE and gastroesophageal reflux disease (GERD) is complex, and differentiating these two conditions continues to be difficult and challenging in clinical practice. The mainstay treatment includes dietary modification, topical steroids, and/or endoscopic dilation. The primary care physician (PCP) plays an important role in improving patient care and quality of life by ensuring early referral and participating in management and follow-up. This article provides an overview of the current knowledge base regarding the disease including epidemiology, genetics, pathogenesis, common clinical presentations, the interplay between EoE and GERD, diagnostic approaches, and therapeutic options available to the PCP.

Eosinophilic esophagitis: pitfalls and controversies in diagnosis and management

Formerly considered a rare disorder, eosinophilic esophagitis (EoE) has emerged as a leading cause of feeding problems in children and an increasingly recognized cause of dysphagia and food impaction in adults. Our understanding of EoE and its complex interplay with gastro-esophageal reflux disease (GERD) has evolved over the past decade and culminated in the introduction of proton pump inhibitor (PPI) responsive EoE as a distinct entity which has added to this complexity. It is now clear that this entity is on the same spectrum as the original EoE, and that PPIs should be considered as part of treatment protocol and should not be recommended as a diagnostic tool. As such, removing the PPI trial from the diagnostic algorithm has been encouraged recently. Recent guidelines and reviews thoroughly address various aspects in EoE pathogenesis and diagnostic workup as well as management endpoints, treatment options and novel therapies. However, despite the recent extensive study and the advances in our knowledge of this disease, unmet needs and pitfalls in diagnostic workup and management of these patients are still to be clarified and will be under focus in this review.

Eosinophilic esophagitis in children: doubts and future perspectives

Background

Eosinophilic esophagitis (EoE) is a chronic immune-mediated inflammatory disorder and represents the leading cause of food impaction. The pathogenesis of EoE is the result of an interplay between genetic, environmental and host immune system factors. New therapeutic approaches for EoE have been proposed. In this manuscript we review the current evidence regarding EoE management in pediatric age, with a particular focus on new findings related to the efficacy and safety of monoclonal antibodies.

Main body

Conventional therapies have failed in treating some patients with EoE, which then requires aggressive procedures such as esophageal dilatation. The most effective available medical therapy for EoE is swallowed topic corticosteroids (fluticasone propionate and budesonide), which have two main drawbacks: they are related to well-known adverse effects (especially in the paediatric population), and there are not enough long-term data to confirm that they are able to reverse the remodelling process of the esophageal mucosa, which is the major cause of EoE symptoms (including dysphagia, abdominal pain, nausea, obstruction, perforation and vomiting). The monoclonal antibodies appear to be an interesting therapeutic approach. However, the studies conducted until now have shown substantial histological improvement not coupled with significant clinical improvements and no significant relationship between a decreasing number of eosinophils and clinical symptoms, highlighting the importance in the pathogenesis of EoE of cells such as T-helper cells, mast cells, B cells, epithelial cells and natural killer cells.

Conclusions

Monoclonal antibodies targeting a signal involved in the pathogenesis of EoE may not break the complex self-propagating inflammatory activation responsible for perpetuation of the inflammatory response and the development of symptoms and complications. We speculate that combined biological therapies targeting more than one molecule or cell may provide better results, with conventional therapies potentially enhancing the effects of antibodies. However, further studies should aim to find the best therapeutic approach to target the cells involved in the remodelling process and to reverse the histological changes in this complex clinical condition.

Serum eosinophilic cationic protein is correlated with food impaction and endoscopic severity in eosinophilic esophagitis

BACKGROUND/AIMS

The aim of the present study was to analyze the diagnostic accuracy of serum eosinophilic cationic protein (ECP) for eosinophilic esophagitis (EoE) and the correlation of ECP with clinical, histopathological, laboratory, and endoscopic features of EoE.

MATERIALS AND METHODS

Fifteen patients with EoE and 14 healthy controls were included in the study. Demographic parameters were recorded. EoE Endoscopic Reference Score (EREFS) was calculated according to endoscopic features, and esophageal biopsies were obtained by a single experienced endoscopist in a patient group. Serum ECP levels (μg/mL), absolute eosinophil count (U/mm3), and maximum peak of eosinophils/high-power field in esophageal biopsies were analyzed.

RESULTS

The median age of all participants was 33.0 (min-max: 18-46) years. There were 27 (93.1%) male patients. Serum ECP level was significantly higher in patients with EoE than in healthy volunteers (20.4 vs. 8.8, p<0.0001). According to the receiver operating characteristic (ROC) curve analysis, ECP had 80% sensitivity and 92.8% specificity to diagnose EoE with a cut-off value of 13.9 µg/mL (area under the ROC curve 0.895; p<0.0001; 95% CI: 0.725-0.978). EREFS (p<0.0001) and the presence of food impaction (p=0.04) were significantly correlated with ECP.

CONCLUSION

Serum ECP is an accurate non-invasive biomarker for EoE with high specificity and sensitivity. In addition, ECP is strongly correlated with EREFS and the symptom of food impaction.

New Developments in the Diagnosis and Treatment of Eosinophilic Esophagitis

PURPOSE OF REVIEW

Eosinophilic esophagitis (EoE) is a chronic, allergen-driven, immune-mediated disease of the esophagus that progresses to esophageal fibrostenosis if left untreated. The aim of this review is to provide a concise update on recent clinically relevant advances in the development of diagnostic and therapeutic approaches for EoE.

RECENT FINDINGS

Current diagnostic and disease monitoring protocols for EoE rely on repetitive endoscopic evaluations and esophageal tissue acquisition for histopathologic analysis. Recent advancements in EoE diagnosis include endoscopic functional lumen imaging probe (FLIP), transnasal endoscopy (TNE), and the emergence of non-invasive diagnostic tools including cytosponge, esophageal string test, and mucosal impedance probe. Biomarkers for EoE have not yet proven their clinical utility. No Food and Drug Administration (FDA)-approved drugs currently exist for the treatment of EoE. Topical corticosteroid, proton-pump inhibitors (PPI), elimination diet, and dilation are the current treatment modalities for confirmed EoE. Promising results from clinical trials are emerging for biologic agents that target the interleukin (IL)-13 and the IL-4/IL-13 receptor, specifically, RPC4046 and dupilumab, respectively. New diagnostic algorithms, non-invasive diagnostic strategies, and treatment modalities for EoE are emerging. Patients with EoE continue to require a multimodal and multi-disciplinary management approach.

Long-term Treatment With Proton Pump Inhibitors Is Effective in Children With Eosinophilic Esophagitis

OBJECTIVES

Proton pump inhibitor (PPI)-responsive eosinophilic esophagitis (EoE) is frequently observed in children, but data on long-term treatment are scarce. The objective of this study is to evaluate the long-term efficacy and safety of PPIs in children with EoE.

METHODS

This prospective study enrolled children with EoE and histological remission to an 8-week esomeprazole trial (1 mg/kg/dose, twice daily). Esomeprazole was maintained at 1 mg/kg/day for 1 year. Symptom recurrence and adverse events were monitored and a follow-up endoscopy was performed at 12 months. Complete histological remission was defined as ≤5 eosinophils/high-power field (eos/hpf), and partial histological remission as >5 and <15 eos/hpf. Patients had no concomitant dietary restrictions or topical steroid.

RESULTS

Fifty-seven children were included. Histological remission on maintenance PPI therapy was present in 40 children (70.1%; 95% CI 56.5-81.5). Long-term remission rate was higher in children with initial complete histological remission than in those with partial remission (81% vs 50%, P = 0.014). Forty-nine children (86%) remained asymptomatic. Pretreatment clinical and histological findings and median PPI dose/kg/day were similar between relapsers and nonrelapsers. Eleven out of 12 children (91.6%) receiving esomeprazole 0.5 mg · kg ·  day for 12 additional months remained in remission. Mild and transient side effects without requiring PPI avoidance were observed in 5 children.

CONCLUSIONS

Up to 70% of children with PPI-responsive EoE remain in histological and clinical remission on a low-dose maintenance treatment at 1-year follow-up, with adequate safety profile. Complete histological remission to an 8-week PPI trial was associated with higher probability of histological remission on maintenance therapy.

Minimally invasive biomarker studies in eosinophilic esophagitis: A systematic review

BACKGROUND

Eosinophilic esophagitis (EoE) is a chronic, inflammatory disease of the esophagus that currently requires repeated endoscopic biopsies for diagnosis and monitoring because no reliable noninvasive markers have been identified.

OBJECTIVE

To identify promising minimally invasive EoE biomarkers and remaining gaps in biomarker validation.

METHODS

We performed a systematic review of EMBASE, Ovid MEDLINE, PubMed, and Web of Science from inception to June 6, 2017. Studies were included if patients met the 2007 consensus criteria for EoE diagnosis, a minimally invasive biomarker was assessed, and the study included at least 1 control for comparison.

RESULTS

The search identified 2094 studies, with 234 reviewed at full-text level, and 49 included in the analysis (20 adult, 19 pediatric, 7 pediatric and adult, and 3 not stated). Most (26 of 49) were published after 2014. Thirty-five studies included healthy controls, 9 analyzed atopic controls, and 29 compared samples from patients with active and inactive EoE. Minimally invasive biomarkers were obtained from peripheral blood (n = 41 studies), sponge or string samples (n = 3), oral or throat swab secretions (n = 2), breath condensate (n = 2), stool (n = 2), and urine (n = 2). The most commonly reported biomarkers were peripheral blood eosinophils (n = 16), blood and string eosinophil granule proteins (n = 14), and eosinophil surface or intracellular markers (n = 12). EoE biomarkers distinguished active EoE from healthy controls in 23 studies, atopic controls in 2 studies, and inactive EoE controls in 20 studies.

CONCLUSION

Several promising minimally invasive biomarkers for EoE have emerged; however, few are able to differentiate EoE from other atopic diseases.

Clinical and Biological Markers in Hypereosinophilic Syndromes

Hypereosinophilic syndromes (HES) are rare, heterogeneous syndromes characterized by markedly elevated eosinophil counts in the blood and/or tissue and evidence of eosinophil-associated pathology. Although parasitic infections, drug hypersensitivity, and other disorders of defined etiology can present as HES (associated HES), treatment is directed at the underlying cause rather than the eosinophilia itself. A number of additional subtypes of HES have been described, based on clinical and laboratory features. These include (1) myeloid HES—a primary disorder of the myeloid lineage, (2) lymphocytic variant HES—eosinophilia driven by aberrant or clonal lymphocytes secreting eosinophil-promoting cytokines, (3) overlap HES—eosinophilia restricted to a single organ or organ system, (4) familial eosinophilia—a rare inherited form of HES, and (5) idiopathic HES. Since clinical manifestations, response to therapy, and prognosis all differ between HES subtypes, this review will focus on clinical and biological markers that serve as markers of disease activity in HES (excluding associated HES), including those that are likely to be useful only in specific clinical subtypes.

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

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

A prospective analysis evaluating tissue biopsy location and its clinical relevance in chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) has a high propensity for recurrence. Studies suggest that eosinophilia influences disease severity and surgical outcomes, but the selection of sinonasal site for measuring eosinophilia has not been examined. The aim of this study was to investigate how region-specific tissue eosinophilia affects radiographic severity, comorbidity prevalence, and polyp recurrence risk following sinus surgery.

METHODS

Eosinophil cationic protein (ECP) levels in uncinate tissue (UT) and nasal polyp (NP) homogenates from 116 CRSwNP patients were measured using enzyme-linked immunosorbent assay (ELISA). Clinical history, radiographic severity, and time to polyp recurrence were obtained from electronic health records. The correlations between baseline Lund-Mackay scores and comorbidities were compared between UT and NP ECP levels. Cox regression and Kaplan-Meier analysis were then performed to assess whether UT or NP ECP better predicted recurrence. Censoring occurred at 4 years or at last follow-up if there was no endoscopic diagnosis of recurrent polyps.

RESULTS

Lund-Mackay scores were significantly correlated with UT and NP ECP (r = 0.46 and 0.26 respectively, p < 0.05). UT but not NP ECP was significantly higher in patients with asthma (p < 0.01) and aspirin-exacerbated respiratory disease (AERD) (p < 0.05). Polyp recurrence risk was only significantly higher for patients with eosinophilic UT tissue (hazard ratio [HR] = 2.84, p = 0.025). When measured in NP, eosinophilia did not predict recurrence.

CONCLUSION

Although ECP in NP was higher than in UT tissue, eosinophilia in UT tissue was a more clinically coherent biomarker of baseline radiographic severity, comorbid asthma and AERD, and prospective polyp recurrence risk than NP eosinophilia.

Tissue Remodeling in Chronic Eosinophilic Esophageal Inflammation: Parallels in Asthma and Therapeutic Perspectives

Chronic eosinophilic inflammation is associated with tissue remodeling and fibrosis in a number of chronic T-helper 2 (Th2)-mediated diseases including eosinophilic esophagitis (EoE) and asthma. Chronic inflammation results in dysregulated tissue healing, leading to fibrosis and end organ dysfunction, manifesting clinically as irreversible airway obstruction in asthma and as esophageal rigidity, strictures, narrowing, dysmotility, dysphagia, and food impactions in EoE. Current therapies for EoE and asthma center on reducing inflammation-driven tissue remodeling and fibrosis with corticosteroids, coupled with symptomatic control and allergen avoidance. Additional control of Th2 inflammation can be achieved in select asthma patients with biologic therapies such as anti-IL-5 and anti-IL-13 antibodies, which have also been trialed in EoE. Recent molecular analysis suggests an emerging role for structural cell dysfunction, either inherited or acquired, in the pathogenesis and progression of EoE and asthma tissue remodeling. In addition, new data suggest that inflammation-independent end organ rigidity can alter structural cell function. Herein, we review emerging data and concepts for the pathogenesis of tissue remodeling and fibrosis primarily in EoE and relevant pathogenetic parallels in asthma, focusing additionally on emerging disease-specific therapies and the ability of these therapies to reduce tissue remodeling in subsets of patients.

Assessing eosinophilic cationic protein as a biomarker for monitoring patients with eosinophilic esophagitis treated with specific exclusion diets

Background

Eosinophilic esophagitis (EoE) is a complex pathology. Attempts have been made in order to relate EoE with the intake of certain food. The problem is to establish which foods are really involved in the pathophysiology of this condition and to objectify a reliable inflammation biomarker for the follow-up of patients undergoing pharmacological treatment and/or diets. Our aim is to assess the food sensitization profile of patients with objective diagnosis of EoE and objectify the utility of ECP as an inflammation biomarker for the follow-up of patients with EoE treated with specific diets, based on the hypothesis that we will observe a decrease and clinical improvement after maintenance of these diets.

Methods

A total of 19 subjects were included between 1 January 2012 and 30 June 2015. Diets based on allergy testing were established. Prior to the initiation of the diets, baseline ECP was determined. Appointments were arranged for the patients between 4 and 6 months later to assess the clinical response to the specific diets and to request a second blood sample for blood counts and serum ECP levels to compare with the previous baseline.

Results

19 patients diagnosed with EoE (12 males and 7 females) between January 2012 and June 2015, aged between 17 and 68 (33.52; SD 13.67 years), were included consecutively, 15 of whom showed optimum response to specific diets based on allergy testing. A statistically significant difference ECP decrease was observed in our patients.

Discussion

Until now most of the studies previously published in reference to the use of ECP as a biomarker for monitoring patients on treatment with diets show consistent but insignificant decreases in ECP levels. However, ECP seems to be a good marker of inflammation if the determinations are performed avoiding confounding factors.

Conclusion

The serial determination of ECP is useful when monitoring patients with EoE treated with specific diets.