Esophageal subepithelial fibrosis in children with eosinophilic esophagitis

Eosinophilic esophagitis in children from Western saudi arabia: relative frequency, clinical, pathological, endoscopic, and immunological study

Background and Purpose. Eosinophilic esophagitis (EE) is an evolving allergic disease with an accelerated incidence. The purpose of this study was to delineate the relative frequency and clinicopathological characteristics of EE in children from western Saudi Arabia. Methods. Children with EE were studied retrospectively between October 2002 and December 2011 at King Abdulaziz University Hospital and International Medical Center. Results. The relative frequency of EE was 0.85% of 2127 upper gastrointestinal endoscopies performed during the study period. Eighteen patients were identified with EE. The median age was 8.6 years (range, 1.5–18 years). Thirteen (72.2%) were males. Dysphagia and vomiting were the most common symptoms. Ten (55.6%) children had history of atopy. Testing for food allergy by skin prick test was positive in 11 (61.1%). The most common endoscopic abnormalities were mucosal longitudinal furrow and loss of vascular pattern followed by patchy specks and strictures. The histopathological findings included increased intraepithelial eosinophils, eosinophilic degranulation, lamina propria fibrosis, and eosinophilic microabscesses. Treatment was initiated by swallowed topical corticosteroids in 12 (66.7%) and oral prednisolone in 6 (33%) patients, followed by low dose of topical corticosteroids and dietary elimination. Conclusions. Eosinophilic esophagitis is an uncommon but evolving problem. A high index of suspicion is required for early identifications and intervention to avoid possible complications.

Use of glucagon in relieving esophageal food bolus impaction in the era of eosinophilic esophageal infiltration

Esophageal food bolus impaction may require an urgent endoscopy. Glucagon is often administered to promote spontaneous passage of the food bolus. Eosinophilic esophagitis is increasingly recognized as a cause of dysphagia, and food impaction is often the presenting symptom. Our study was aimed at determining the effectiveness of glucagon in relieving esophageal foreign body obstruction in general and in the setting of esophageal eosinophilic infiltration (EEI). A retrospective chart review was performed using the ICD codes and the emergency department database of adult patients presenting with symptoms of esophageal food bolus impaction from July 2004 to October 2010. Response to glucagon was defined as symptomatic relief of obstruction prior to endoscopic intervention. A total of 213 episodes of esophageal food bolus obstruction in 192 patients were identified during the study period. Glucagon was given in 125 cases of which 41 had a response (32.8 %). A total of 170 episodes had an Esophagogastroduodenoscopy performed either during the impaction event or at a later date. Of the 60 patients' biopsies, 45 had received glucagon (17 with EEI, 28 without EEI). None of the 17 episodes with EEI as compared to 8 of the 28 without EEI responded to glucagon (0 % vs. 28.5 %, p = 0.017). Glucagon is effective in about one third of patients with esophageal food bolus impaction, which is consistent with historical data. Patients with EEI appear less likely to respond to glucagon.

Tissue remodeling in eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a recently recognized, immune-mediated disease characterized clinically by symptoms of esophageal dysfunction and histologically by eosinophil-predominant inflammation. The chronic esophageal eosinophilia of EoE is associated with tissue remodeling that includes epithelial hyperplasia, subepithelial fibrosis, and hypertrophy of esophageal smooth muscle. This remodeling causes the esophageal rings and strictures that frequently complicate EoE and underlies the mucosal fragility that predisposes to painful mucosal tears in the EoE esophagus. The pathogenesis of tissue remodeling in EoE is not completely understood, but emerging studies suggest that secretory products of eosinophils and mast cells, as well as cytokines produced by other inflammatory cells, epithelial cells, and stromal cells in the esophagus, all contribute to the process. Interleukin (IL)-4 and IL-13, Th2 cytokines overproduced in allergic disorders, have direct profibrotic and remodeling effects in EoE. The EoE esophagus exhibits increased expression of transforming growth factor (TGF)-β1, which is a potent activator of fibroblasts and a strong inducer of epithelial-mesenchymal transition. In addition, IL-4, IL-13, and TGF-β all have a role in regulating periostin, an extracellular matrix protein that might influence remodeling by acting as a ligand for integrins, by its effects on eosinophils or by activating fibrogenic genes in the esophagus. Presently, few treatments have been shown to affect the tissue remodeling that causes EoE complications. This report reviews the potential roles of fibroblasts, eosinophils, mast cells, and profibrotic cytokines in esophageal remodeling in EoE and identifies potential targets for future therapies that might prevent EoE complications.

Cow's milk elimination: a novel dietary approach to treat eosinophilic esophagitis

OBJECTIVES

Cow's-milk protein is one of the food antigens responsible for causing eosinophilic esophageal inflammation in a majority of children. We describe our experience with treating eosinophilic esophagitis (EoE) in children by eliminating only cow's milk from their diets.

METHODS

This retrospective study assessed the short-term clinical and histological response to eliminating cow's-milk protein from the diet of children with EoE. Only patients undergoing a subsequent upper endoscopy to assess their histological response were included in this analysis.

RESULTS

We identified 17 (12 boys and 5 girls) children with EoE who excluded only cow's milk from their diet. Remission was induced in 11 of 17 (65%) patients; within the remission group, 7 (41%) achieved complete histological remission and 4 patients (24%) were in significant histological remission. The mean peak pre- and posttreatment counts for those in remission were 76 ± 40 and 2 ± 4 (P < 0.01), respectively.

CONCLUSIONS

Elimination of cow's milk-induced clinical and histological remission in 65% (95% confidence interval 42%-88%) of children with EoE in whom it was attempted. This approach offers distinct advantages over other dietary treatment approaches for the initial management of children with EoE. The role of eliminating cow's milk alone for the treatment of EoE warrants further prospective study.

Dietary therapy can reverse esophageal subepithelial fibrosis in patients with eosinophilic esophagitis: a historical cohort

BACKGROUND

Fibrosis of the esophageal lamina propria is a known complication of eosinophilic esophagitis (EoE). To date, therapy with topical corticosteroids has been shown to reverse esophageal fibrosis in some patients; however, there is little evidence to suggest that dietary therapy can also reverse it. Our aim was to examine whether dietary therapy alone can reverse esophageal fibrosis in children with EoE.

METHODS

We performed a historical cohort study based on children with EoE who had esophageal fibrosis on pretreatment biopsies using trichrome staining. Post-treatment biopsies were analyzed for fibrosis reversal, and results were compared between patients treated with dietary restriction and those that received topical steroids. Clinical characteristics (age, symptoms, duration of symptoms prior to therapy, treatment type, and duration of therapy) were recorded. Histological markers (eosinophil numbers and eosinophilic degranulation in both epithelium and lamina propria, basal zone hyperplasia, and the presence of eosinophilic microabscesses in the epithelium) were examined by reviewing hematoxylin and eosin-stained biopsies and by immunohistochemical staining. These were examined as potential predictors for fibrosis reversal.

RESULTS

Fibrosis resolved following both dietary restriction and topical steroids (3/17 and 5/9 patients respectively, P = 0.078). Post-treatment symptom resolution and decreased intraepithelial eosinophil numbers were found to be the only significant predictors of fibrosis resolution.

CONCLUSIONS

Dietary restriction alone, similar to topical steroids, can reverse fibrosis in children with EoE.

The prevalence and diagnostic utility of endoscopic features of eosinophilic esophagitis: a meta-analysis

BACKGROUND & AIMS

Endoscopic findings such as esophageal rings, strictures, narrow-caliber esophagus, linear furrows, white plaques, and pallor or decreased vasculature might indicate the presence of eosinophilic esophagitis (EoE). We aimed to determine the prevalence and diagnostic utility of endoscopic features of EoE.

METHODS

We conducted a systematic review and meta-analysis. PubMed, EMBASE, and gastrointestinal meeting abstracts were searched to identify studies that included more than 10 patients with EoE and reported endoscopic findings. Pooled prevalence, sensitivity, specificity, and predictive values were calculated using random- and mixed-effects models.

RESULTS

The search yielded 100 articles and abstracts on 4678 patients with EoE and 2742 without (controls). In subjects with EoE, the overall pooled prevalence was as follows: esophageal rings, 44%; strictures, 21%; narrow-caliber esophagus, 9%; linear furrows, 48%; white plaques, 27%; and pallor/decreased vasculature, 41%. Substantial heterogeneity existed among studies. Results from endoscopy examinations were normal in 17% of patients, but this number decreased to 7% when the analysis was limited to prospective studies (P < .05). Overall levels of sensitivity were modest, ranging from 15% to 48%, whereas levels of specificity were greater, ranging from 90% to 95%. Positive predictive values ranged from 51% to 73% and negative predictive values ranged from 74% to 84%.

CONCLUSIONS

There is heterogeneity among studies in the reported prevalence of endoscopic findings in patients with EoE, but in prospective studies at least 1 abnormality was detected by endoscopy in 93% of patients. The operating characteristics of endoscopic findings alone are inadequate for diagnosis of EoE. Esophageal biopsy specimens should be obtained from all patients with clinical features of EoE, regardless of the endoscopic appearance of the esophagus.

Eosinophilic gastroenteritis: an update

Eosinophilic gastroenteritis (EGE) is characterized by dense eosinophilic inflammation of one or several digestive tract sections. The symptoms include abdominal pain, weight loss, vomiting and diarrhea. Biopsy samples taken during endoscopic examination allows the diagnosis of the disease. An infiltration of >30 eosinophils per high-power field in at least five high-power fields, exhibiting signs of eosinophilic degranulation and extending to the muscularis mucosa or submucosa are all histological indications of EGE. EGE is traditionally classified into three forms depending on the depth of inflammation in the wall (mucosal, muscular or serosal). This, together with the digestive tract segments involved, determines the clinical presentation. The natural history of EGE includes three different evolutionary patterns, since patients may suffer a single outbreak, a recurrent course or even chronic disease. Corticosteroids are the most frequently used therapy for EGE; dietary treatments should be also considered. Surgery has been limited to solving obstruction and small bowel perforation.

Angiogenic remodeling in pediatric EoE is associated with increased levels of VEGF-A, angiogenin, IL-8, and activation of the TNF-α-NFκB pathway

OBJECTIVES

Eosinophilic esophagitis (EoE) is a clinicopathologic diagnosis characterized by inflammation and infiltration of eosinophils at the esophageal mucosa. The underlying etiology of EoE remains elusive. Inflammatory diseases, such as asthma, are associated with structural remodeling of the airways, which includes angiogenesis. The aims of this study were to determine the angiogenic profile of esophageal mucosa in children presenting with EoE and to evaluate the putative mechanism(s) underlying the early inflammatory angiogenic response observed in EoE.

METHODS

Endoscopically obtained biopsy samples from 18 EoE and 18 control pediatric patients were analyzed for angiogenic markers (CD31, von Willebrand factor, vascular cell adhesion molecule-1) and tissue levels of angiogenic factors (vascular endothelial growth factor [VEGF]-A, VEGF-R2, angiogenin and interleukin [IL]-8). Expression levels of angiogenic factors and markers in EoE and control samples were characterized by immunofluorescence analysis and quantitative reverse transcriptase-polymerase chain reaction. Vascular density of biopsy samples was evaluated by immunofluorescence analysis.

RESULTS

Samples from patients with EoE exhibited higher levels of von Willebrand factor, CD31, and vascular cell adhesion molecule-1, which is suggestive of neovascularization and an activated endothelium. Moreover, EoE biopsies showed greater levels of the angiogenesis promoters VEGFA, angiogenin, and IL-8. Interestingly, there were greater cellular levels of tumor necrosis factor-α in EoE samples compared with controls. Furthermore, there were higher nuclear levels of p50 and p65 subunits of NFκB and lower cellular levels of the inhibitor of NFκB, IκB-α, in EoE samples compared with controls.

CONCLUSIONS

We demonstrate increased angiogenesis in the esophageal mucosa of pediatric patients with EoE. The data also provided evidence that the angiogenic factors VEGF-A, angiogenin, and IL-8 were prominently involved in promoting angiogenic remodeling.

Contribution of endoscopy in the management of eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a clinicopathological entity characterized by a set of symptoms similar to gastroesophageal reflux disease and eosinophilic infiltration of the esophageal epithelium. EoE is an emerging worldwide disease as documented in many countries. Recent reports indicate that EoE is increasingly diagnosed in both pediatric and adult patients although the epidemiology of this new disease entity remains unclear. It is unclear whether EoE is a new disease or a new classification of an old esophageal disorder. Esophagogastroduodenoscopy (EGD) and biopsies with histological examination of esophageal mucosa are required to establish the diagnosis of EoE, verify response to therapy, assess disease remission, document and dilate strictures and evaluate symptom recurrence of EoE. Repeated endoscopies with biopsies are necessary for monitoring of disease progression and treatment efficacy. EGD has a fundamental role in the diagnosis and management of EoE, forming an essential part of the investigation and follow-up of this condition. EoE is now considered a systemic disorder and not only a local condition with an important immunological background. One of the aims of research in EoE is to study non-invasive markers, such as immune indicators found in plasma, that correlate with local presence of EoE in esophageal tissues. Studies over the next few years will provide new information about diagnosis, pathogenesis, endoscopic/histologic criteria, non-invasive markers, novel and more efficacious treatments, as well as establishing natural history. Randomized clinical trials are urgently called for to inform non-invasive diagnostic tests, hallmarks of natural history and more efficacious treatment approaches for patients with EoE. The collaboration between pediatric and adult clinical and experimental studies will be paramount in the understanding and management of this disease.

Eosinophilic gastrointestinal diseases--clinically diverse and histopathologically confounding

Eosinophilic gastrointestinal diseases are a group of chronic diseases characterized by a range of symptoms caused by eosinophilic inflammation of various parts of the gastrointestinal tract. Other causes for eosinophilia need to be ruled out prior to making the diagnosis of EGIDs. The most common form of EGID is eosinophilic esophagitis (EoE), an antigen-driven disease that afflicts children and adults and has been identified across the world. Histological features include dense eosinophilia of the esophageal mucosa, eosinophil degranulation, eosinophil microabscess formation, and other features of epithelial inflammation including basal zone hyperplasia and rete pege elongation. Treatments include dietary exclusions and topical corticosteroids.

MicroRNA profiling in mucosal biopsies of eosinophilic esophagitis patients pre and post treatment with steroids and relationship with mRNA targets

Background

The characterization of miRNAs and their target mRNAs involved in regulation of the immune process is an area of intense research and relatively little is known governing these processes in allergic inflammation. Here we present novel findings defining the miRNA and mRNA transcriptome in eosinophilic esophagitis (EoE), an increasing recognized allergic disorder.

Methods

Esophageal epithelial miRNA and mRNA from five paired biopsies pre- and post-treatment with glucocorticosteroids were profiled using Taqman and Affymetrix arrays. Validation was performed on additional paired biopsies, untreated EoE specimens and normal controls. Differentially regulated miRNAs and mRNAs were generated, within which miRNA-mRNA target pairs with high predicted confidence were identified.

Results

Compared to the post-glucocorticoid treated esophageal mucosa, of all the 377 miRNA sequences examined, 32 miRNAs were significantly upregulated and four downregulated in the pre-treated biopsies. MiR-214 was the most upregulated (150 fold) and miR-146b-5b, 146a, 145, 142-3p and 21 were upregulated by at least 10 fold. Out of 12 miRNAs chosen for validation by qRT-PCR, five (miR-214, 146b-5p, 146a, 142-3p and 21) were confirmed and 11 shared the same trend. When the expression of the 12 miRNAs in the EoE mucosa was compared to unrelated normal mucosa, six (miR-214, 146b-5p, 146a, 21, 203, and 489) showed similar significant changes as in the paired samples and 10 of them shared the same trend. In the same five pairs of samples used to profile miRNA, 311 mRNAs were down-regulated and 35 were up-regulated in pre-treated EoE mucosa. Among them, 164 mRNAs were identified as potential targets of differentially regulated miRNAs. Further analysis revealed that immune-related genes, targeted and non-targeted by miRNAs, were among the most important genes involved in the pathogenesis of EoE.

Conclusions

Our findings add to the accumulating body of data defining a regulatory role for miRNA in immune and allergic processes.

Biomarkers for eosinophilic esophagitis: a review

BACKGROUND

The complex pathophysiology of eosinophilic esophagitis (EoE) provides several candidate biomarkers that could be used to establish diagnosis, assess response to therapy, and document disease recurrence.

OBJECTIVE

To review the literature on various biomarkers of EoE, with respect to their correlation to disease activity and response to treatment.

DATA SOURCES

A literature search was performed using PubMed and OVID with keyword combinations of EoE and various potential biomarkers.

STUDY SELECTIONS

Between 2006 and 2012, 26 studies that investigated the correlation of various tissue and serum biomarkers with EoE were identified.

RESULTS

The markers investigated included eotaxins-1,-2, and -3, interleukin-5 (IL-5), interleukin-13 (IL-13), eosinophil-derived neurotoxin, mast cell markers, absolute eosinophil count, and micro-RNAs. Several studies have shown a positive correlation between eotaxin-3, IL-5, and IL-13 messenger RNA (mRNA) expression in esophageal tissue and disease activity. Eotaxin-3 mRNA staining was found to have 89% sensitivity for diagnosing EoE. Staining for mast cells and their products has also shown promise. More recently, a microRNA signature that can potentially distinguish EoE from non-EoE esophagitis has been identified.

CONCLUSION

The studies are quite heterogeneous with respect to their methodology and the biomarker(s) studied, but most have investigated tissue biomarkers. Eotaxin-3 and IL-13 have emerged as the most promising ones with respect to sensitivity and degree of positive correlation to disease process. Future research on biomarkers for EoE should include longitudinal studies, establishment of normal values, effects of concomitant atopic diseases, age and gender, and validation of methodology of the tests.

Esophageal diameter is decreased in some patients with eosinophilic esophagitis and might increase with topical corticosteroid therapy

BACKGROUND & AIMS

The rapid response to topical corticosteroids makes it hard to implicate fibrosis as the cause of dysphagia in patients with eosinophilic esophagitis (EoE). We examined surrogates of esophageal expansion using minimal and maximal esophageal diameter (EDmin and EDmax) in barium swallow examinations.

METHODS

Eleven patients evaluated at Mayo Clinic, Rochester (8 female, median age 40, median diagnosis 36 months, median symptom duration 132 months) underwent barium esophagrams to determine EDmin and EDmax before and after 6 weeks of topical corticosteroid therapy. We assessed parameter reproducibility (in healthy volunteers), baseline EDmin and EDmax, postcorticosteroid changes in EoE patients, and correlation with clinical response.

RESULTS

EDmin and EDmax were reproducible, with nonsignificant variance in the 2 esophagrams in control subjects (P = .44 and P = .66, respectively). Baseline EDmax was reduced in EoE at 19 mm (range, 13-26 mm) vs 24 mm (range, 19-29 mm) in controls (P = .004). About 50% of the EoE patients had EDmax and min values within the 10th to 90th percentile of controls (45% and 55%, respectively). Clinical improvement by Mayo Dsyphagia Questionnaire did not correlate with postcorticosteroid luminal change (P = .19 for EDmax; P = .75 for EDmin). Median increases in postcorticosteroid EDmax and EDmin were not statistically significant (P = .15 and .1, respectively). However, they were significant in patients with abnormal baseline EDmax (n = 6; 2 mm; P = .01) and EDmin (n = 5; 3 mm; P = .02).

CONCLUSIONS

Esophageal diameter is a reproducible parameter that is frequently decreased in EoE, but normal in approximately 50% of patients. Those with narrowing might respond to steroids, but it is unclear if narrowing causes dysphagia.

Pediatric and adult eosinophilic esophagitis: similarities and differences

Early in the 1990s, several case series described adults suffering from dysphagia and children with refractory reflux symptoms, both accompanied by an eosinophil-predominant infiltration, thereby conclusively distinguishing it from gastroesophageal reflux disease. Eosinophilic esophagitis (EoE) was recognized as its own entity in the adult and in the pediatric literature. In the last decade, evidence has accumulated that EoE represents a T-helper (Th)2-type inflammatory disease. Remodeling of the esophagus is a hallmark of EoE, leading to esophageal dysfunction and bolus impaction. Familial occurrence and disease association with single-nucleotide polymorphisms underscore the influence of genetics in this disease. Eosinophilic esophagitis may affect individuals at any age, although the clinical presentation is highly age dependent. There is a significant allergic bias in the EoE population, with the majority of patients having concurrent allergic rhinitis, asthma, eczema, and/or a history of atopy. One noteworthy difference is that in children, EoE seems to be primarily a food antigen-driven disease, whereas in adults, mainly aeroallergen sensitization has been observed. Treatment modalities for EoE include the 3Ds: drugs, diet, and dilation. The crucial question of whether adult and pediatric EoE are different phenotypes of one single entity or whether we are confronted with two different diseases is still open. Here, we review similarities and differences between EoE in adults and children.

Eosinophilic esophagitis: epithelial mesenchymal transition contributes to esophageal remodeling and reverses with treatment

BACKGROUND

Mechanisms underlying esophageal remodeling with subepithelial fibrosis in subjects with eosinophilic esophagitis (EoE) have not been delineated.

OBJECTIVES

We sought to explore a role for epithelial mesenchymal transition (EMT) in subjects with EoE and determine whether EMT resolves with treatment.

METHODS

Esophageal biopsy specimens from 60 children were immunostained for epithelial (cytokeratin) and mesenchymal (vimentin) EMT biomarkers, and EMT was quantified. Subjects studied had EoE (n = 17), indeterminate EoE (n = 15), gastroesophageal reflux disease (n = 7), or normal esophagus (n = 21). EMT was analyzed for relationships to diagnosis, eosinophil counts, and indices of subepithelial fibrosis, eosinophil peroxidase, and TGF-β immunostaining. EMT was assessed in pretreatment and posttreatment biopsy specimens from 18 subjects with EoE treated with an elemental diet, 6-food elimination diet, or topical corticosteroids (n = 6 per group).

RESULTS

TGF-β1 treatment of esophageal epithelial cells in vitro for 24 hours induced upregulation of mesenchymal genes characteristic of EMT, including N-cadherin (3.3-fold), vimentin (2.1-fold), and fibronectin (7.5-fold). EMT in esophageal biopsy specimens was associated with EoE (or indeterminate EoE) but not gastroesophageal reflux disease or normal esophagus and was correlated to eosinophil counts (r = 0.691), eosinophil peroxidase (r = 0.738), and TGF-β (r = 0.520) immunostaining and fibrosis (r = 0.644) indices. EMT resolved with EoE treatments that induced clinicopathologic remission with reduced eosinophil counts. EMT decreased significantly after treatment by 74.1% overall in the 18 treated subjects with EoE; pretreatment versus posttreatment EMT scores were 3.17 ± 0.82 versus 0.82 ± 0.39 (P < .001), with similar decreases within treatment groups. Pretreatment/posttreatment EMT was strongly correlated with eosinophil counts for combined (r = 0.804, P < .001) and individual treatment groups.

CONCLUSIONS

EMT likely contributes to subepithelial fibrosis in subjects with EoE and resolves with treatments that decrease esophageal inflammation, and its resolution correlates with decreased numbers of esophageal eosinophils.

Significance of para-esophageal lymph nodes in food or aeroallergen-induced iNKT cell-mediated experimental eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a recently recognized inflammatory disorder driven by food hypersensitivity; however, the specific foods and mechanisms involved are unclear. In patients with EoE, we have found that hypersensitivities to corn and peanuts are the most common. Accordingly, we sensitized and exposed mice either intranasally or intragastrically with corn or peanut extract or saline. Esophageal eosinophilia, the genes of eosinophil-directed cytokines, and allergen-induced antibodies were examined in mice challenged with corn or peanut extract or saline. A high number of esophageal lamina propria eosinophils as well as eosinophilic microabscesses, intraepithelial eosinophils, extracellular eosinophilic granules, thickened and disrupted epithelial mucosa, and mast cell hyperplasia were observed in the esophagus of peanut or corn allergen-challenged mice. Mechanistic analysis indicated that para-esophageal lymph nodes might be critical in the trafficking of eosinophils to the esophagus and in EoE association to airway eosinophilia. Furthermore, experimentation with gene-targeted mice revealed that peanut allergen-induced EoE was dependent on eotaxin and invariant natural killer T (iNKT) cells, as CD1d and eotaxin-1/2 gene-deficient mice were protected from disease induction. Thus we provide evidence that para-esophageal lymph nodes are involved in food- or aeroallergen-induced eosinophilia and patchy EoE pathogenesis, likely a mechanism dependent on eotaxins and iNKT cells.

Conservative long-term treatment of children with eosinophilic esophagitis

BACKGROUND

Current treatments of eosinophilic esophagitis (EoE), including restrictive diets or glucocorticoids, provide only transient improvement. Proton pump inhibitor (PPI) use in EoE does not lead to histologic improvement; however, the long-term use of PPI on symptoms and prevention of complications has not been evaluated.

OBJECTIVE

To evaluate the use of PPI as maintenance therapy in children with EoE.

METHODS

Eosinophilic esophagitis was diagnosed based on initial endoscopic biopsies and persistent eosinophilic inflammation despite PPI therapy. Inclusion criteria included diagnosis of EoE and PPI use as primary maintenance treatment. Patients were excluded if they were treated with dietary or glucocorticoid therapy. Histologic evidence of inflammation as well as degree of subepithelial fibrosis at presentation was compared with most recent biopsies while receiving PPI therapy.

RESULTS

Thirty-eight patients (30 males and 8 females; average age 6.7 ± 5.4 years) fulfilled inclusion criteria. Duration of follow-up was 3.0 ± 2.4 years. At presentation, vomiting was significantly more frequent in the younger patients, whereas dysphagia occurred more frequently in the older patients. At follow-up, 26 patients were asymptomatic, and the remaining 12 patients' symptoms were significantly improved. No complications of stricture or food impaction were seen. Significant eosinophilic inflammation persisted in 28 patients. No difference in degree of subepithelial fibrosis at diagnosis compared with most recent biopsies. The z-scores of the treated EoE patients significantly improved.

CONCLUSION

Patients with EoE treated with PPIs show an improvement in symptoms and z-scores despite persistent eosinophilic inflammation. PPI treatment may be useful maintenance therapy in children with EoE.

[Eosinophilic oesophagitis]

BACKGROUND

Eosinophilic oesophagitis is a chronic inflammatory condition in the oesophagus. There has been increasing awareness of this disease in recent years as a common cause of dysfunction of the oesophagus in children and adults.

MATERIAL AND METHOD

The review is based on a search in PubMed, scrutiny of reference lists and the authors' experience of adults and children with eosinophilic oesophagitis.

RESULTS

Eosinophilic oesophagitis is being diagnosed increasingly often in western countries. Men are affected three times as often as women. The disease may start at any age, but does so most frequently in children and young adults. Dysphagia and impaction of food in the oesophagus are the most common symptoms in adolescents and adults. In children the commonest symptoms are eating problems, abdominal pain, nausea and retarded growth. In many patients the mechanism behind the condition is probably an allergic reaction in the oesophagus to food, and over half the patients have an atopic disposition. The diagnosis is based on clinical findings, typical findings on endoscopy and eosinophilic granulocytes in the oesophageal mucosa. Treatment possibilities include restriction of diet, locally acting corticosteroids and endoscopic dilatation.

INTERPRETATION

Eosinophilic oesophagitis is being diagnosed in an increasing number of patients, but it is not certain whether this is due to increased occurrence or increased awareness by doctors. Knowledge of the disease is important because simple endoscopic or medical treatment leads to a good result in most patients, and can prevent complications such as stricture formation and food impaction in the oesophagus.

Reflectance confocal microscopy for the diagnosis of eosinophilic esophagitis: a pilot study conducted on biopsy specimens

BACKGROUND

Diagnosis of eosinophilic esophagitis (EoE) currently requires endoscopic biopsy and histopathologic analysis of the biopsy specimens to count intraepithelial eosinophils. Reflectance confocal microscopy (RCM) is an endomicroscopy technology that is capable of obtaining high-resolution, optically sectioned images of esophageal mucosa without the administration of exogenous contrast.

OBJECTIVE

In this study, we investigated the capability of a high-speed form of RCM, termed spectrally encoded confocal microscopy (SECM), to count intraepithelial esophageal eosinophils and characterize other microscopic findings of EoE.

DESIGN

A total of 43 biopsy samples from 35 pediatric patients and 8 biopsy samples from 8 adult patients undergoing EGD for EoE were imaged by SECM immediately after their removal and then processed for routine histopathology. Two SECM readers, trained on adult cases, prospectively counted intraepithelial eosinophils and detected the presence of abscess, degranulation, and basal cell hyperplasia on SECM images from the pediatric patients. A pathologist blinded to the SECM data analyzed the same from corresponding slides.

SETTING

The Gastrointestinal Unit, Massachusetts General Hospital.

RESULTS

Eosinophils by SECM demonstrated a higher reflectance than the surrounding cells and other inflammatory cells. There was good correlation between SECM and histology maximum eosinophil counts/high-power field (R = 0.76, P < .0001). Intra- and interobserver correlations for SECM counts were very good (R = 0.93 and R = 0.92, respectively; P < .0001). For the commonly used eosinophil count cutoff of 15 per high-power field, the sensitivity and specificity of SECM for EoE were 100%. The sensitivity and specificity for abscess, degranulation, and basal cell hyperplasia were 100% and 82%, 91% and 60%, and 94% and 80%, respectively. Intra- and interobserver agreements for these microscopic features of EoE were very good (κ = 0.9/0.9, 0.84/1.0, 0.91/0.81, respectively).

LIMITATION

Ex vivo study.

CONCLUSIONS

This study demonstrates that RCM can be used to accurately count intraepithelial eosinophils and identify other microscopic abnormalities associated with EoE on freshly excised biopsy samples. These findings suggest that RCM may be developed into a tool for assessing eosinophilic infiltration in the esophagus in vivo.

Eosinophilic esophagitis: rapidly advancing insights

Eosinophilic esophagitis (EoE) now represents a commonly recognized disorder among both pediatric and adult patients presenting to allergy and gastroenterology clinics throughout the world. The consequences of this localized and eosinophil-predominant inflammation of the esophagus can have an outsized and profound systemic and emotional impact for patients and their families. Unlike gastroesophageal reflux disease (GERD), whose symptoms closely overlap with those of EoE, EoE represents a primarily antigen-driven disorder whose symptoms and pathology are therapeutically mitigated with either long-term dietary control or chronic steroid therapies, rather than the acid-suppressive medications that are the mainstay of GERD treatment. Beyond the dissimilarities in their responses to treatment, these disorders are distinct in their gene expression profiles, heredity, genetic underpinning, and linkage with atopy. The antigen-driven nature of EoE has been reinforced by the remarkable impact of therapies utilizing elemental formulas to control the disease as well as a number of reports linking aeroallergens to seasonal worsening of disease.

CCR3 Blockade Attenuates Eosinophilic Ileitis and Associated Remodeling

Intestinal remodeling and stricture formation is a complication of inflammatory bowel disease (IBD) that often requires surgical intervention. Although eosinophils are associated with mucosal remodeling in other organs and are increased in IBD tissues, their role in IBD-associated remodeling is unclear. Histological and molecular features of ileitis and remodeling were assessed using immunohistochemical, histomorphometric, flow cytometric, and molecular analysis (real-time RT-PCR) techniques in a murine model of chronic eosinophilic ileitis. Collagen protein was assessed by Sircol assay. Using a spontaneous eosinophilic Crohn's-like mouse model SAMP1/SkuSlc, we demonstrate an association between ileitis progression and remodeling over the course of 40 weeks. Mucosal and submucosal eosinophilia increased over the time course and correlated with increased histological inflammatory indices. Ileitis and remodeling increased over the 40 weeks, as did expression of fibronectin. CCR3-specific antibody-mediated reduction of eosinophils resulted in significant decrease in goblet cell hyperplasia, muscularis propria hypertrophy, villus blunting, and expression of inflammatory and remodeling genes, including fibronectin. Cellularity of local mesenteric lymph nodes, including T- and B-lymphocytes, was also significantly reduced. Thus, eosinophils participate in intestinal remodeling, supporting eosinophils as a novel therapeutic target.

Subepithelial collagen deposition, profibrogenic cytokine gene expression, and changes after prolonged fluticasone propionate treatment in adult eosinophilic esophagitis: a prospective study

BACKGROUND

Recent research shows that both pediatric and adult patients with eosinophilic esophagitis (EoE) experience esophageal remodeling marked by increased collagen deposition in which TGF-β plays an important role. However, limited data are available on the intensity and reversibility of fibrous remodeling in adults with EoE.

OBJECTIVE

We sought to analyze differences in collagen deposition in the lamina propria (LP) and profibrogenic cytokine gene expression along with other changes induced by prolonged treatment with fluticasone propionate in adults with EoE.

METHODS

Ten adults given consecutive diagnoses of EoE were studied prospectively. Deep esophageal biopsy specimens were obtained before and after 1 year of treatment with fluticasone propionate. Collagen deposition in the LP was assessed in tissue sections with the aid of the Masson trichrome technique. IL5, TGFB1, fibroblast growth factor 9 (FGF9), and CCL18 gene expression was quantified through real-time PCR. EoE results were compared among samples from 10 adult patients with gastroesophageal reflux disease and 10 control subjects with healthy esophagi.

RESULTS

Patients with EoE showed a significant increase in subepithelial collagen deposition; this correlated positively with eosinophil density in the LP and the patient's age. Prolonged steroid treatment induced a nonsignificant reduction in subepithelial fibrosis, which remained significantly higher than in control subjects. Profibrogenic cytokine gene expression also increased in patients with EoE, with IL5 (P < .001), FGF9 (P = .005), and CCL18 (P = .008) all significantly upregulated. After 1 year of treatment, a reduction was observed in gene expression; for CCL18 expression, this decrease was statistically significant (P < .001).

CONCLUSIONS

Esophageal remodeling is associated with upregulated gene expression of profibrogenic cytokines in adults with EoE. Prolonged treatment with fluticasone propionate leads to a nonsignificant reduction in subepithelial collagen deposition accompanied by downregulation of profibrogenic cytokine gene expression, with that of CCL18 being especially significant.

Identification of specific foods responsible for inflammation in children with eosinophilic esophagitis successfully treated with empiric elimination diet

OBJECTIVES

Eosinophilic esophagitis (EoE) is an immune-mediated chronic inflammatory disorder triggered by food antigen(s). A 6-food elimination diet (SFED) excluding cow's milk, soy, wheat, egg, peanuts/tree nuts, and seafood has been shown to induce remission in a majority of children with EoE. The goal of the present study was to identify specific food antigens responsible for eosinophilic esophageal inflammation in children with EoE who had achieved histological remission with the SFED.

PATIENTS AND METHODS

In this analysis, we retrospectively analyzed children with EoE who completed subsequent single-food reintroductions that led to identification of foods causing disease recurrence. Repeat upper endoscopy with biopsies was performed after single-food introductions. Recurrence of esophageal eosinophilia following a food reintroduction identified that food antigen as a cause of EoE.

RESULTS

A total of 36/46  (25 M/11F) children who were initially successfully treated with SFED completed this trial; the mean age was 7.6  ±  4.3 years. The most common foods identified were 25 to cow's milk (74%), 8 to wheat (26%), 4 to eggs (17%), 3 to soy (10%), and 1 to peanut (6%). Milk was 8 times more likely to cause EoE compared with wheat, the next most common food (95% confidence interval 2.41-26.62, P = 0.0007).

CONCLUSIONS

Serial single-food reintroductions following induction of histological remission with the SFED can lead to the identification of specific causal food antigen(s) in EoE. Cow's milk was the most common food identified in subjects with EoE treated with SFED. A subset of children with EoE may develop tolerance to their food sensitivities while on the SFED.

Eosinophilic esophagitis: trials and tribulations

Eosinophilic esophagitis (EE) is a recently recognized form of pan-esophagitis, which is characterized by the presence of at least 15 eosinophils per high power field on esophageal histology. EE is closely associated with atopic disorders and occurs predominantly in male patients. Young children are more likely to be sensitized to food allergens whilst aeroallergen sensitization predominates in older children and adults--a pattern reminiscent of the "atopic march". EE presents with a diverse range of gastrointestinal symptoms, including regurgitation, vomiting, feeding difficulties or refusal in infancy, in addition to dysphagia and food bolus impaction in older children and adults. The diagnosis may also be ascertained incidentally in patients undergoing gastroscopy for other suspected gastrointestinal conditions, such as gastroesophageal reflux disease or celiac disease. Complications mainly relate to subepithelial remodeling and fibrosis which may result in dysmotility, dysphagia and esophageal strictures. The proportion of EE patients at risk of these complications is unknown due to a paucity of data on the natural history of EE. There are only few randomized controlled trials assessing the efficacy of treatment modalities for EE, which currently either involve food allergen elimination or use of swallowed aerosolized corticosteroids. This article aims to discuss the complex issues of the diagnosis and long-term management that confront clinicians who care for children with EE.

Emerging management concepts for eosinophilic esophagitis in children

Eosinophilic esophagitis (EoE) is a newly recognized condition that appears to be increasing in incidence for as yet unknown reasons. It can occur at any age and presents both to gastroenterologists and allergists. Clinical manifestations range from gastrointestinal symptoms (vomiting, feeding difficulties, dysphagia or food bolus impaction) to co-existing atopic conditions (asthma, allergic rhinitis or eczema). The diagnosis requires demonstration of at least 15 eosinophils per high power field on esophageal histology, usually in the context of resistance to proton pump inhibitor treatment or a normal 24-h esophageal pH monitoring study. The differential diagnosis between EoE and gastroesophageal reflux disease (GERD) can be problematic as there is significant clinical overlap between both conditions. Although difficult-to-manage esophageal strictures are well recognized in patients with long-standing EoE, little is known about risk factors for the development of this complication. There is a paucity of data on both the natural history and optimal long-term management of EoE. Current treatment options include food allergen elimination diets, use of topical aerosolized corticosteroids, or a combination of the two. Pediatric case studies have been provided to illustrate the complexity of decision points that often arise in the management of these patients. This paper aims to discuss the various strategies currently available to clinicians in the management of EoE and highlights gaps in the current evidence base that urgently require further research.

Role of eosinophils in inflammatory bowel and gastrointestinal diseases

Inflammatory bowel diseases (IBD) are characterized by the invasion of leukocytes into the intestinal mucosa. However, a mixed inflammatory picture is observed that includes neutrophils, lymphocytes, monocytes, and eosinophils. To this day, the role of eosinophils in health and in disease remains unclear. Investigations into their function stem primarily from allergic diseases, asthma, and parasitic infections. This makes it even more difficult to discern a role for the fascinating eosinophil in IBDs because, unlike the lung or the skin, eosinophils reside in normal intestinal mucosa and increase in disease states; consequently, an intricate system must regulate their migration and numbers. These granulocytes are equipped with the machinery to participate in gastrointestinal (GI) inflammation and in the susceptible microenvironment, they may initiate or perpetuate an inflammatory response. A significant body of literature characterizes eosinophils present in the GI microenvironment where they have the potential to interact with other resident cells, thus promoting intestinal remodeling, mucus production, epithelial barrier, cytokine production, angiogenesis, and neuropeptide release. A number of lines of evidence support both potential beneficial and deleterious roles of eosinophils in the gut. Although studies from the gut and other mucosal organs suggest eosinophils affect mucosal GI inflammation, definitive roles for eosinophils in IBDs await discovery.

Toward uniformity in the diagnosis of eosinophilic esophagitis (EoE): the effect of guidelines on variability of diagnostic criteria for EoE

OBJECTIVES

Recent consensus guidelines for diagnosis of eosinophilic esophagitis (EoE) have been published. Whether these guidelines have standardized diagnostic criteria for EoE is unknown. We aimed to determine if the EoE guidelines had an impact on the diagnostic criteria reported in the EoE literature, and whether the previously observed variability in diagnostic criteria has become more uniform.

METHODS

Two investigators independently conducted a MEDLINE search from 1 January 2007 through 30 June 2010 for all publications reporting EoE in human subjects, and also searched the proceedings of the 2007-2010 American College of Gastroenterology and American Gastroenterological Association meetings, using a predefined search strategy. Data were extracted from all relevant publications.

RESULTS

Of the 799 publications identified, 149 original reports, 99 reviews, and 165 abstracts were included. In all, 32 original reports (21%) used diagnostic criteria consistent with each of the three components of the consensus guidelines. There was a significant increase when comparing original articles published after the release of the guidelines with those published earlier (31 vs. 6%, P<0.001). The proportion of original articles using 15 eosinophils per high-power field (eos/hpf) as a histological cut-point increased significantly (P=0.001). There was still substantial variability in biopsy protocols and eosinophil count methodology. The majority of original articles did not report microscope high-power field (HPF) area.

CONCLUSIONS

The proportion of original reports with diagnostic criteria consistent with the consensus guidelines has increased significantly. However, the majority of articles still did not conform to all three of the criteria in the guidelines, and biopsy and eosinophil count protocols continue to demonstrate significant variability. Standardization of biopsy and eosinophil count protocols is needed.

Eosinophilic esophagitis: updated consensus recommendations for children and adults

Eosinophilic esophagitis (EoE) is a clinicopathologic condition of increasing recognition and prevalence. In 2007, a consensus recommendation provided clinical and histopathologic guidance for the diagnosis and treatment of EoE; however, only a minority of physicians use the 2007 guidelines, which require fulfillment of both histologic and clinical features. Since 2007, the number of EoE publications has doubled, providing new disease insight. Accordingly, a panel of 33 physicians with expertise in pediatric and adult allergy/immunology, gastroenterology, and pathology conducted a systematic review of the EoE literature (since September 2006) using electronic databases. Based on the literature review and expertise of the panel, information and recommendations were provided in each of the following areas of EoE: diagnostics, genetics, allergy testing, therapeutics, and disease complications. Because accumulating animal and human data have provided evidence that EoE appears to be an antigen-driven immunologic process that involves multiple pathogenic pathways, a new conceptual definition is proposed highlighting that EoE represents a chronic, immune/antigen-mediated disease characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation. The diagnostic guidelines continue to define EoE as an isolated chronic disorder of the esophagus diagnosed by the need of both clinical and pathologic features. Patients commonly have high rates of concurrent allergic diatheses, especially food sensitization, compared with the general population. Proved therapeutic options include chronic dietary elimination, topical corticosteroids, and esophageal dilation. Important additions since 2007 include genetic underpinnings that implicate EoE susceptibility caused by polymorphisms in the thymic stromal lymphopoietin protein gene and the description of a new potential disease phenotype, proton pump inhibitor-responsive esophageal eosinophila. Further advances and controversies regarding diagnostic methods, surrogate disease markers, allergy testing, and treatment approaches are discussed.

Understanding eosinophilic esophagitis: the cellular and molecular mechanisms of an emerging disease

Eosinophilic esophagitis (EoE) has been increasingly recognized as a unique clinicopathological entity over the past two decades. In this short time, the mechanisms of a complex disease have begun to emerge. Patient studies suggest that EoE is an immunologic disease related to atopy. At the cellular level, eosinophils, mast cells, and B and T lymphocytes are increased in the esophageal mucosa in a patchy distribution throughout the length of the esophagus. Laboratory investigations have implicated aeroallergens, food allergens, and a unique T helper type 2 cytokine profile. EoE appears to be an antigen-driven hypersensitivity reaction characterized by a mixed IgE-dependent/delayed-type reaction and a distinct cascade of cytokines and growth factors. The causative events that lead to EoE in humans remain unknown.

Tryptase staining of mast cells may differentiate eosinophilic esophagitis from gastroesophageal reflux disease

OBJECTIVES

Mast cells may contribute to the pathogenesis of eosinophilic esophagitis (EoE), but their role in diagnosis is unknown. Our aim was to determine whether tryptase staining of esophageal mast cells differentiates EoE from gastroesophageal reflux disease (GERD) and has utility for diagnosis of EoE.

METHODS

We performed a case-control study comparing patients with EoE, defined by consensus guidelines, to GERD patients with eosinophils on esophageal biopsy. Immunohistochemistry was performed with mast cell tryptase. The density (mast cells/mm2) and intensity (0-4 scale) of mast cell staining was compared between groups after masking the diagnosis. Receiver operating characteristic (ROC) curves were constructed, and the area under the curve (AUC) was calculated to assess mast cell staining as both a stand-alone diagnostic test and an adjunctive assay with eosinophil counts.

RESULTS

Fifty-four EoE (mean age 24 years; 69% male; mean 146 eosinophils per high-power field (eos/hpf)) and 55 GERD (mean age 34 years; 60% male; mean 20 eos/hpf) patients were analyzed. The maximum epithelial tryptase density was higher in EoE than in GERD (162±87 mast cells/mm2 vs. 67±54; P<0.001). Mast cells were diffusely distributed throughout the biopsy in more EoE than GERD patients (41 vs. 7%; P<0.001). Tryptase density and eosinophil count were only weakly correlated (R2=0.09; P=0.002). The AUC was 0.84 for tryptase staining alone, and 0.96 for the combination of mast cells and eosinophils.

CONCLUSIONS

Patients with EoE have higher levels of tryptase-positive mast cells compared with GERD patients, improving the diagnostic value of biopsies beyond eosinophil counts alone. Mast cell tryptase may have utility as a diagnostic assay for EoE.

Esophageal subepithelial fibrosis and hyalinization are features of eosinophilic esophagitis

BACKGROUND AND OBJECTIVE

Eosinophilic esophagitis (EE) is characterized by marked esophageal mucosal eosinophilia on histological examination. Although the clinical and histological features of EE are increasingly recognized, the overlap of clinical symptoms and histological findings with gastroesophageal reflux disease (GERD) can lead to diagnostic difficulty. In children with EE we sought to define the frequency of subepithelial fibrosis and define the clinical correlates of this feature. The specificity of this finding in EE was obtained by comparison with a matched group of children with GERD, to ascertain its usefulness as a histological aid in differentiating between the 2 diagnoses.

PATIENTS AND METHODS

Comparison was made between 27 patients with EE and 24 patients with GERD, whose endoscopic biopsy specimens included subepithelial tissue. Demographic data, symptoms, endoscopic findings, and other histological findings were also compared.

RESULTS

In contrast to patients with GERD, those with EE more commonly reported longer periods of symptoms (especially dysphagia) and were more likely to have endoscopic abnormalities. Subepithelial fibrosis was present in 89% of patients with EE and 37.5% of patients with GERD (P < 0.0001). The features of fibrosis in EE included uniformity and hyalinization, whereas the fibrosis in GERD was predominantly associated with lymphoid tissue.

CONCLUSIONS

Subepithelial fibrosis commonly occurs in children with EE and is associated with increased age and length of symptoms. We propose that along with mucosal eosinophilic infiltration the presence of subepithelial fibrosis is a feature of EE.

Fluticasone and food allergen elimination reverse sub-epithelial fibrosis in children with eosinophilic esophagitis

BACKGROUND

Symptoms of vomiting and dysphagia in children with eosinophilic esophagitis may be related to the development of mucosal fibrosis.

AIM

Our aims were to (1) investigate esophageal fibrosis in children with EoE compared to patients with gastroesophageal reflux disease and normal individuals, and (2) to assess the degree of mucosal fibrosis in patients with EoE before and after medical treatment.

METHODS

A retrospective analysis of esophageal biopsies from patients with EoE, GERD, and normal mucosa was performed. Demographic data, clinical information, eosinophil number, and sub-epithelial fibrosis was compared among the groups. A similar comparison was performed in EoE patients, before and after therapy.

RESULTS

Esophageal biopsies from 53 children were included, of which 17 with EoE, 17 GERD, and 19 were normal. A significantly higher number of eosinophils and greater fibrosis was found in EoE patients vs. GERD and normal (fibrosis grade 2: 13 patients in the EoE group vs. one patient for each control group; p=0.0001). After therapy, a significant decrease in fibrosis and eosinophils number was noted in EoE patients [fibrosis grade 2: 10 (71.5%) patients vs. one (7.1%) patient, and eosinophil count was 35.5/HPF vs. 13.4/HPF, pre- and post-therapy, respectively; p<0.05]. The decrease in esophageal fibrosis paralleled the improvement in the related clinical symptoms.

CONCLUSION

A higher degree of esophageal fibrosis was found in patients with EoE compared to GERD or normal esophagus. Conventional therapy in EoE improved obstructive symptoms, decreased eosinophils count, and reversed the degree of fibrosis. We suggest that appropriate therapy in patients with EoE will improve clinical symptoms and histology.

Food allergy and eosinophilic esophagitis

PURPOSE OF REVIEW

Eosinophilic esophagitis (EoE) is a chronic allergic disease of the esophagus. A mix of immediate, IgE-mediated and delayed, non-IgE-mediated immunological reactions to foods is thought to play a role in EoE. Our purpose is to review available clinical and research evidence for this link between food allergy and EoE.

RECENT FINDINGS

Various food elimination trials resulted in various rates of disease remission. Exclusive amino acid formula-based dietary trials resulted in more than 90% remission in children with EoE. Empiric elimination diets consisting of avoidance of foods commonly known to cause hypersensitivity reactions resulted in 50-74% disease remission. When diets were tailored based on results from skin prick and atopy patch tests, remission rates were comparable. Translational research studies performed on esophageal tissues and peripheral blood of patients with EoE demonstrated an allergic T-helper type 2 phenotype, though mechanisms linking the disease to food allergens are not fully addressed.

SUMMARY

Foods appear to be important allergic triggers in EoE. Identification of these triggers, however, remains a challenge. Research is needed to elucidate at which point in the pathogenesis of EoE foods become important so that their role can be better understood, and develop better tests to identify these foods.

Eotaxin and FGF enhance signaling through an extracellular signal-related kinase (ERK)-dependent pathway in the pathogenesis of Eosinophilic esophagitis

Background

Eosinophilic esophagitis (EoE) is characterized by the inflammation of the esophagus and the infiltration of eosinophils into the esophagus, leading to symptoms such as dysphagia and stricture formation. Systemic immune indicators like eotaxin and fibroblast growth factor were evaluated for possible synergistic pathological effects. Moreover, blood cells, local tissue, and plasma from EoE and control subjects were studied to determine if the localized disease was associated with a systemic effect that correlated with presence of EoE disease.

Method

Real-time polymerase chain reaction from peripheral blood mononuclear cells (PBMC), immunohistochemistry from local esophageal biopsies, fluid assays on plasma, and fluorescence-activated cell sorting on peripheral blood cells from subjects were used to study the systemic immune indicators in newly diagnosed EoE (n = 35), treated EoE (n = 9), Gastroesophageal reflux disease (GERD) (n = 8), ulcerative colitis (n = 5), Crohn's disease (n = 5), and healthy controls (n = 8).

Result

Of the transcripts tested for possible immune indicators, we found extracellular signal-regulated kinase (ERK), Bcl-2, bFGF (basic fibroblast growth factor), and eotaxin levels were highly upregulated in PBMC and associated with disease presence of EoE. Increased FGF detected by immunohistochemistry in esophageal tissues and in PBMC was correlated with low levels of pro-apoptotic factors (Fas, Caspase 8) in PBMC from EoE subjects. Plasma-derived bFGF was shown to be the most elevated and most specific in EoE subjects in comparison to healthy controls and disease control subjects.

Conclusion

We describe for the first time a possible mechanism by which increased FGF is associated with inhibiting apoptosis in local esophageal tissues of EoE subjects as compared to controls. Eotaxin and FGF signaling pathways share activation through the ERK pathway; together, they could act to increase eosinophil activation and prolong the half-life of eosinophils in local tissues of the esophagus in EoE subjects.

Feeding dysfunction in children with eosinophilic gastrointestinal diseases

OBJECTIVES

Feeding dysfunction (FD) seen in younger children with eosinophilic gastrointestinal disease (EGID) has not been well described. Thus, our aim was to further characterize FD in children with EGIDs.

METHODS

A retrospective medical record analysis of 200 children seen over 12 months in a multidisciplinary Gastrointestinal Eosinophilic Diseases Program was performed. The clinical data of 33 children identified as also having FD were examined, including information obtained by history, physical examination, feeding evaluation, review of nutritional data, allergy testing and histologic assessment of mucosal biopsies.

RESULTS

Of 200 children with EGIDs, 16.5% had significant FD. The median age of this group was 34 months (range: 14-113 months). A variety of learned maladaptive feeding behaviors were reported in 93.9%. Frequent gagging or vomiting occurred in 84.8%. Food sensitivity was documented in 88% while 52% had other allergic disease. Twenty one percent were diagnosed with failure to thrive and 69.7% required individual or group feeding therapy. Forty-two percent had residual eosinophilia of >15 per HPF on esophageal biopsies performed at the time of symptoms.

CONCLUSIONS

FD is prevalent in children with EGIDs often presenting as maladaptive learned feeding behaviors with altered mealtime dynamics and physical difficulties in eating mechanics. FD can persist even after eosinophilic inflammation is successfully treated. Awareness of the increased prevalence of FD in children with EGIDs with enable earlier recognition of this problem, resulting in a comprehensive, individualized treatment plan with the desired outcome of improving the development, feeding, and nutrition of these children.

Do eosinophil numbers differentiate eosinophilic esophagitis from gastroesophageal reflux disease?

CONTEXT

Although the healthy esophageal mucosa contains no eosinophils, eosinophilic infiltration is observed in 2 major clinicopathologic settings: gastroesophageal reflux disease (GERD) and eosinophilic esophagitis (EE). The prevalence of EE is increasing in many countries, and this increase seems only partly to be due to a better awareness of the pathology, following the relatively recent description of EE. Gastroesophageal reflux disease and EE represent 2 entities that do not respond to the same treatment modalities and, thus, need to be distinguished. However, diagnostic criteria of EE have been defined arbitrarily, and the more recent articles tend to prove that the overlap with GERD is probably greater than initially believed, leading the authors to advise strict exclusion of GERD before considering the diagnosis of EE.

OBJECTIVES

To provide pathologists with the currently proposed histologic criteria of GERD and EE, to stress the need to combine these criteria with clinical data and endoscopic findings, and to outline the remaining controversies.

DATA SOURCES

This review is based on selected articles identified by a PubMed (US National Library of Medicine, Bethesda, Maryland) search of the literature in English for GERD and EE, a recent review by the American Gastroenterological Association (Bethesda), the Proceedings of the First International Gastrointestinal Eosinophil Research Symposium, and the authors' experience.

CONCLUSION

Proper identification of the etiology of eosinophilic infiltration of the esophagus allows accurate medical or surgical treatment and follow-up. Eosinophilic esophagitis and GERD diagnoses require integration of the histologic findings with the clinical and endoscopic data.

Medical and nutrition management of eosinophilic esophagitis in children

Eosinophilic esophagitis (EoE), esophageal inflammation that occurs in the absence of acidification, is characterized by mucosal eosinophilia and epithelial proliferative changes. Depending on the patient's age, EoE may present as a feeding disorder, vomiting, abdominal pain, dysphagia, or food impaction. In the absence of a well-delineated natural history, case reports suggest that in some individuals with EoE, the disease progresses to esophageal fibrosis and then presumably irreversible esophageal dysfunction. Successful management of EoE in children requires (1) identifying the causative agents for a given patient, (2) implementing effective medical and/or nutrition therapies, and (3) establishing a continuum of long-term care that delivers the child to adulthood without esophageal dysfunction.

Involvement of mast cells in eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EE) is an emerging disorder with poorly understood pathogenesis.

OBJECTIVE

Whereas prior studies have primarily focused on the role of eosinophils in disease diagnosis and pathogenesis, this study investigates the involvement of mast cells.

METHODS

Total and degranulated mast cell counts were correlated to microarray and RT-PCR data to generate transcriptome expression profiles related to mast cell number and degranulation in patients with EE and healthy control subjects.

RESULTS

Esophageal mastocytosis and mast cell degranulation were readily apparent in patients with EE compared with control subjects (P < .01), as assessed by staining for total mast cells and the presence of extracellular mast cell tryptase (P < .01). Microarray analysis revealed that mast cell levels correlated with the dysregulation of 0.8% (301 genes) of the genome, which was partially distinct from the genes that correlated with tissue eosinophilia. The expression of transcripts for the mast cell proteases carboxypeptidase A3 and tryptase, but not chymase, correlated with mast cell levels and distinguished patients with EE from control subjects. Suprabasilar mast cell counts (P < .01) and degranulation (P < .01) were proportional with KIT ligand mRNA expression. Treatment of patients with EE with swallowed fluticasone propionate normalized levels of mast cells and the mast cell-related transcriptome in responder patients.

CONCLUSION

Herein we have identified local mastocytosis and mast cell degranulation in the esophagi of patients with EE; identified an esophageal mast cell-associated transcriptome that is significantly divergent from the eosinophil-associated transcriptome, with carboxypeptidase A3 mRNA levels serving as the best mast cell surrogate marker; and provided evidence for the involvement of KIT ligand in the pathogenesis of EE.

Severe dysphagia in children with eosinophilic esophagitis and esophageal stricture: an indication for balloon dilation?

BACKGROUND

Esophageal stricture is one of the most severe complications in eosinophilic esophagitis (EoE). Clinical practice is based on limited data and some treatments are still considered controversial. We report on our experience in the treatment of severe dysphagia and esophageal strictures in EoE, especially using balloon dilation, showing the clinical practice in our pediatric population.

PATIENTS AND METHODS

This was a single-center retrospective study between December 2002 to November 2007, identifying all of the pediatric patients with severe dysphagia in the context of EoE. Demographic data and the results of various treatment regimens were reviewed.

RESULTS

Severe dysphagia was identified in 13 cases (77% male, mean age 12.8 +/- 4.4 years). Endoscopic findings were mucosal edema (62%), long segment strictures, esophagitis, and off-white appearance in 31%. Histologically, >20 eosinophils per high-power field were present in all of the patients. Medical treatment consisted of proton pump inhibitor PPI (77%), montelukast (31%), local corticosteroids (54%), systemic corticosteroids (8%), elemental diet (15%), and food elimination diet (61%). A combined therapeutic approach was performed in all of the cases, due to clinical relapse or no response to monotherapy. Good response was obtained clinically in 70%, endoscopically in 62%, and histologically in 75%. Relapses were observed in 46% of the cases. Balloon dilation was necessary in 31% of the cases (mean dilation sessions 3.3 +/- 0.95), being effective in 100% of patients, without complications.

CONCLUSIONS

In our pediatric series, combined medical (corticosteroids, elemental diet, and food elimination diet) and endoscopic approach (repeated balloon dilation) were effective and safe in patients with severe EoE and esophageal stricture.

Approach to dysphagia in the young patient in the era of eosinophilic esophagitis

Eosinophilic esophagitis (EoE) has emerged as an important cause of dysphagia and food impactions in young adults. Previously considered a rare condition, an increasing number of cases of EoE have been attributable to a rising incidence and a growing awareness of the condition. Typical endoscopic features include concentric mucosal rings, linear furrowing, white exudates, and a narrow caliber esophagus. Current consensus guidelines define EoE by 1) the presence of characteristic symptoms, especially dysphagia and food impactions in adults, 2) >or= 15 eosinophils per high power field in esophageal tissue, and 3) exclusion of other disorders with similar presentations (eg, gastroesophageal reflux disease). Current knowledge about the pathophysiology implicates food allergens, aeroallergens, and genetic factors. The main treatment options for EoE are proton pump inhibitors, dietary manipulation, and topical or oral glucocorticoids. Endoscopic dilation may be performed in patients who do not respond to medical therapy. This review highlights recent insights into the diagnosis and management of EoE in young adults.

Indoor insect allergens are potent inducers of experimental eosinophilic esophagitis in mice

EE is an emerging disease reported in children and adults of urbanized countries, where indoor insect allergens are major health risk factors. Review of our hospital patient database uncovered that a number of EE patients have hypersensitivity to indoor cat, dog, cockroach, and dust mite allergens. We tested the hypothesis whether inhaled indoor insect allergens are effective inducers of experimental EE. We delivered cat, dog, cockroach, and dust mite allergen extracts intranasally to wild-type and eotaxin-1/2-, CCR3-, and IL-5-deficient mice. Interestingly, wild-type mice exposed to cockroach or dust mite allergens develop a significant increase in the levels of esophageal eosinophils and mast cells compared with saline-challenged mice. The eosinophil numbers in the esophagus of cockroach- and dust mite-exposed mice were 18.3+/-6.8/mm2 and 33.4+/-11.1/mm2 compared with 2.3+/-1.8/mm2 and 2.1+/-1.2/mm2 in saline-challenged mice. Additionally, we observed an additive effect of these two allergens in inducing esophageal eosinophilia and mastocytosis. Histopathological analysis detected intraepithelial esophageal eosinophilia in mice exposed to both allergens. Furthermore, mice exposed to cockroach and/or dust mite had increased levels of total IgE and antigen-specific IgG1 in the blood and increased esophageal expression of eosinophil-active cytokines (IL-13) and chemokines (eotaxin-1). Notably, mice deficient in eotaxin-1/2, CCR3, and IL-5 showed ablated esophageal eosinophilia following cockroach or dust mite allergen exposure. These data indicate that indoor insect allergens are potent inducers of IL-5 and eotaxin-mediated esophageal eosinophilia. These experimental studies are in accordance with clinical data but may have some limitations inherent to animal models of human disease.

Mucosal immunology, eosinophilic esophagitis, and other intestinal inflammatory diseases

The gastrointestinal mucosa constitutes the largest host-environment interface of the body. It uses both innate and adaptive immune mechanisms to provide protection from the diverse onslaught of foods, microbes, and other ingested products. The innate immune system is genetically encoded and evolutionarily ancient, possesses no memory, and lacks diversity. In contrast, the adaptive immune system is quite diverse, develops memory, and undergoes expansion after stimulation. The gastrointestinal mucosa is charged with the difficult task of mounting protective responses against invading microorganisms while simultaneously maintaining an overall state of nonresponsiveness or tolerance to innocuous substances, such as commensal bacteria and food antigens. Perturbation or malfunction of these complex protective mechanisms results in diseases, such as inflammatory bowel diseases, celiac disease, or eosinophilic gastrointestinal diseases.

Cysteinyl leukotrienes acting via granule membrane-expressed receptors elicit secretion from within cell-free human eosinophil granules

BACKGROUND

Cysteinyl leukotrienes (cysLTs) are recognized to act via receptors (cysLTRs) expressed on cell surface plasma membranes. Agents that block cysLT(1) receptor (cysLT(1)R) are therapeutics for allergic disorders. Eosinophils contain multiple preformed proteins stored within their intracellular granules. Cell-free eosinophil granules are present extracellularly as intact membrane-bound organelles in sites associated with eosinophil infiltration, including asthma, rhinitis, and urticaria, but have unknown functional capabilities.

OBJECTIVE

We evaluated the expression of cysLTRs on eosinophil granule membranes and their functional roles in eliciting protein secretion from within eosinophil granules.

METHODS

We studied secretory responses of human eosinophil granules isolated by subcellular fractionation. Granules were stimulated with cysLTs, and eosinophil cationic protein and cytokines were measured in the supernatants. Receptor expression on granule membranes and eosinophils was evaluated by flow cytometry and Western blot.

RESULTS

We report that receptors for cysLTs, cysLT(1)R, cysLT(2) receptor, and the purinergic P2Y12 receptor, are expressed on eosinophil granule membranes. Leukotriene (LT) C(4) and extracellularly generated LTD(4) and LTE(4) stimulated isolated eosinophil granules to secrete eosinophil cationic protein. MRS 2395, a P2Y12 receptor antagonist, inhibited cysLT-induced eosinophil cationic protein release. Montelukast, likely not solely as an inhibitor of cysLT(1)R, inhibited eosinophil cationic protein release elicited by LTC(4) and LTD(4) as well as by LTE(4).

CONCLUSION

These studies identify previously unrecognized sites of localization, the membranes of intracellular eosinophil granule organelles, and function for cysLT-responsive receptors that mediate cysteinyl leukotriene-stimulated secretion from within eosinophil granules, including those present extracellularly.

An update on the immunopathogenesis of eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a chronic clinicopathological entity characterized by large numbers of intraepithelial eosinophils infiltrating the esophageal mucosa, which is not caused by gastroesophageal reflux. This disease has become widely recognized over the past few years and new methods have been developed to reveal its underlying pathophysiological mechanisms. Owing to the high prevalence of food and/or airborne allergen sensitization in EoE patients, the allergic nature of the disease had to be defined, which has certain factors in common with other IgE-dependent entities, such as bronchial asthma or allergic rhinitis. Of these, some cytokines and chemokines previously studied in asthma have also been implicated in molecular mechanisms causing eosinophil-rich esophageal inflammation. However, the role played by IgE in relation to the esophageal eosinophilic infiltrate must be clarified, together with the possible function of mast cells in the inflammatory infiltrate and its activation stimuli. A putative role has also been recently suggested for gastroesophageal reflux in the origin of EoE that should be profoundly analyzed, together with the role of specific genes implicated in other digestive inflammatory disorders. This article reviews recent advances in the immunopathogenesis of EoE, which should also consider other pathways to activate the esophageal mucosal immune system.

Eosinophilic Esophagitis: Current Aspects of a Recently Recognized Disease

Eosinophilic esophagitis (EoE) is a chronic clinicopathological entity characterized by large numbers of intraepithelial eosinophils infiltrating the esophageal mucosa. The inflammation leads to alterations in the caliber and the motility of the organ, which determines esophageal symptoms, especially dysphagia and frequent food impaction. Firstly described in 1978, EoE represents today an increasingly recognized disease, with cases coming from all developed countries and rising epidemiology. The origin of EoE has been related to allergy to food components or inhalants, and a number of studies support a Th2-type reaction in the origin of the disease. Thus, several treatment strategies based on controlling the exposition to triggering allergens or therapies using anti-allergic drugs have demonstrated efficacy in EoE. Since EoE frequently presents with esophageal stenosis, endoscopic dilation has been also used in treating these patients, but a high risk of complications has been documented. However, single treatment strategies have not been compared to a placebo group in most of studies, and we do not know the long-term consequences of eosinophilic inflammation, esophageal fibrous remodeling or its possible modifications using different therapies. Furthermore, we lack of a common accepted therapeutic end-point to assess the efficacy of the treatment: from mere resolution of symptoms to full control of esophageal inflammation. This article summarizes the current knowledge about the epidemiology, origin and pathogenesis of the disease, and discuses several practical questions, especially those related to how the affected patients should be treated.

Resolution of remodeling in eosinophilic esophagitis correlates with epithelial response to topical corticosteroids

BACKGROUND

Esophageal remodeling occurs in eosinophilic esophagitis (EE) patients but whether the components of remodeling in the subepithelium are reversible by administration of topical oral corticosteroids is unknown.

METHODS

We quantitated the degree of lamina propria remodeling in esophageal biopsies obtained before and after at least 3 months of therapy with budesonide in 16 pediatric EE subjects. In addition, we investigated whether corticosteroid therapy modulated vascular activation (expression of VCAM-1; level of interstitial edema), TGFbeta(1) activation (levels of TGFbeta(1), phosphorylated Smad2/3), and performed a pilot analysis of a polymorphism in the TGFbeta(1) promoter in relation to EE subjects who had reduced remodeling with budesonide therapy.

RESULTS

EE subjects were stratified based on the presence (n = 9) or absence (n = 7) of decreased epithelial eosinophilia following budesonide. Patients with residual eosinophil counts of <or=7 eosinophils per high power field in the epithelial space (responders) demonstrated significantly reduced esophageal remodeling with decreased fibrosis, TGFbeta(1) and pSmad2/3 positive cells, and decreased vascular activation in association with budesonide therapy. Responders were more likely to have a CC genotype at the -509 position in the TGFbeta(1) promoter.

CONCLUSIONS

Reductions in epithelial eosinophils following budesonide therapy were associated with significantly reduced esophageal remodeling.

Advances in research of eosinophilic esophagitis

Eosinophilic esophagitis (EE) is being recognized with increasing frequency. Numerous studies have investigated its pathogenesis, pathophysiologic manifestations, and effective diagnosis and treatment methods in recent years. In this article, we will review the recent advances in research on EE.