Cysteinyl leukotriene levels in esophageal mucosal biopsies of children with eosinophilic inflammation: are they all the same?

Pharmacologic Management of Non-Eosinophilic Esophagitis Eosinophilic Gastrointestinal Diseases

Data for pharmacologic treatments for non-eosinophilic esophagitis (EoE) eosinophilic gastrointestinal diseases (EGIDs) are limited. Nevertheless, because of the increasing understanding of EGID pathogenesis, a number of medications are used to treat EGIDs, though all are currently off-label. Initial therapy generally starts with corticosteroids, and "topical" delivery is preferred over systemic due to long-term side effects. A number of other small molecules could potentially be used, ranging from allergy medications to immunosuppressants. Biologics are also being used and investigated for EGIDs and represent promising targeted therapies. Multiple therapeutic targets have also been identified, many of which overlap with EoE targets.

Paediatric eosinophilic oesophagitis in New Zealand: A 3-year prospective study

AIM

Eosinophilic oesophagitis (EoE) is a rare, chronic, relapsing immune/antigen-mediated disease characterised by symptoms of oesophageal dysfunction, with a paucity of data among New Zealand (NZ) children. This 3-year prospective study aimed to characterise EoE diagnosed nationally and to describe initial treatment strategies adopted.

METHODS

Information on new diagnoses of paediatric EoE was obtained via the New Zealand Paediatric Surveillance Unit, through monthly questionnaires.

RESULTS

From February 2014 to January 2017, 73 new cases (74% male) of EoE were reported, including 74% NZ European, 10% Asian, 7% Māori, 5% Middle-Eastern and 3% Pacific peoples. Median age of symptom onset was 4 years; dysphagia (48%) was the most common, followed by vomiting/regurgitation (40%), food impaction (19%) and epigastric pain (16%). A co-morbid history of other allergic conditions was present in 62% of patients, and 41% had a first degree relative with atopy. Seventy-nine percent of patients had abnormal endoscopic findings, most commonly linear furrows and white plaques; none had strictures. Median eosinophil count per high-powered field was 40 and 50 in the mid and distal oesophagus, respectively. Fifty-four percent of patients were initially managed with dietary manipulation alone (four required elemental feeds, five nasogastric tubes). Fifty-four percent of patients were treated with swallowed corticosteroids and 7% with prednisone. One patient was also treated with a leukotriene receptor antagonist.

CONCLUSION

This first prospective study on paediatric patients with EoE in NZ finds similar demographics and disease characteristics as in other populations despite our unique ethnic population. Long-term prospective observational data should significantly improve our knowledge of this rare condition.

CONCENTRATIONS OF CYSTEINYL LEUKOTRIENES IN VARIOUS BIOLOGICAL FLUIDS OF CHILDREN WITH BRONCHIAL ASTHMA, ATOPIC DERMATITIS AND FOOD PROTEIN INDUCED ENTEROCOLITIS

Clinical manifestation of food allergy is characterized by polymorphic cutaneous, respiratory and gastrointestinal syndromes. Leukotrienes occupy a key place in the pathogenesis of a wide range of inflammatory diseases, including bronchial asthma, allergic rhinitis, atopic dermatitis, hives, allergic conjunctivitis, atherosclerotic cardio-vascular lesions system, inflammatory bowel disease, multiple sclerosis, cancer, etc. Better understanding of general pathophysiological mechanisms of allergic realization put the focus on the studying of cysteinyl leukotrienes biological effects in infants with atopic dermatitis and food-protein induced enterocolitis important. Aim. To optimize the diagnosis of allergic lesions of the gastrointestinal tract in children. Methods. The study was conducted in the allergy center and children clinic of the «Institute Pediatrics, Obstetrics and Gynecology named after academician O. Lukyanova of NAMS of Ukraine». Children were included from September 2017 to June 2018. We examined 60 patients aged from 3 months to 3 years old, including 22 patients with atopic dermatitis, 18 children with food-protein induced enterocolitis, 8 patients with bronchial asthma in the stage of aggravation and 12 practically healthy children (control group). Medical examination have been perfomed, general IG E and specific serum IG E were defined by ImmunoCAP (Phadia, 100), as well as concentrations of cysteinyl leukotrienes (LTB4, LTC4, LTE4) in biological liquids (serum, saliva, urine) using immunoenzyme method using the production sets of the "Enzolifescience" (USA) company on the analyzer-photometer Multiskan Plus "Labsystems". The results of the received data were processed statistically. The probability of differences was estimated with Student’s t-test and Tau Kendall rank correlation test. The difference was considered significant at p <0.05. Results. A significant increase in the concentrations of cysteinyl leukotrienes (C4, D4, E4) in the blood, urine and saliva was found in infants with allergic skin diseases, gastro-intestinal and respiratory tract surveyed during manifestation the disease compared with the control group. Comparison of concentrations of leukotrienes in urine and saliva of children with atopic dermatitis (AD), food-protein induced enterocolitis (FPIE) and asthma did not find credible. However, in the serum of patients with asthma, the concentration of cysteinyl leukotrienes was significantly higher (703.9±68.7) pg / ml than in children with enterocolitis induced by dietary proteins (509.3±57.4) pg / ml and significantly did not differ from patients with atopic dermatitis (695.2±46.3) pg / ml. According to the results of Kendall Tau correlation test, no significant Spearman rank correlation was found between the cysteinyl leukotrienes concentration in blood and urine – r=0.14 (p>0.05), blood and saliva r=0.07 (p>0.05), urine and saliva r=–0.52 (p>0.05). Conclusions. Increase in cysteinyl leukotrienes concentrations in serum, urine and saliva of children of early age with allergic skin diseases, respiratory and gastrointestinal tract was found. The absence of significant Spearman rank correlation between concentrations of leukotrienes in blood and urine, blood and saliva, saliva and urine shows that it is possible to select any biological fluid, saliva or urine, as a non-invasive way to determine the leukotriene concentrations for monitoring activity of allergic inflammation.

Leukotriene receptor expression in esophageal squamous cell cancer and non-transformed esophageal epithelium: a matched case control study

BACKGROUND

Leukotriene B4 (LTB4R and LTB4R2) and cysteinyl leukotriene receptors (CYSLTR1 and CYSLTR2) contribute to malignant cell transformation. We aimed to investigate the expression of LTB4R, LTB4R2, CYSLTR1 and CYSLTR2 in esophageal squamous cell carcinoma and adjacent non-transformed squamous epithelium of the esophagus, as well as in control biopsy samples from esophageal squamous epithelium of patients with functional dyspepsia.

METHODS

Expression of LTB4R, LTB4R2, CYSLTR1 and CYSLTR2 was analyzed by immunohistochemistry (IHC) and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in biopsy samples of 19 patients with esophageal squamous cell cancer and 9 sex- and age-matched patients with functional dyspepsia.

RESULTS

LTB4R, LTB4R2, CYSLTR1 and CYSLTR2 were expressed in all biopsy samples. Major findings were: 1) protein levels of all leukotriene receptors were significantly increased in esophageal squamous cell cancer compared to control mucosa (p < 0.05); 2) CYSLTR1 and CYSLTR2 gene expression was decreased in cancer tissue compared to control at 0.26-fold and 0.23-fold respectively; 3) an up-regulation of LTB4R (mRNA and protein expression) and a down-regulation of CYSLTR2 (mRNA expression) in non-transformed epithelium of cancer patients compared to control (p < 0.05) was observed.

CONCLUSIONS

The expression of leukotriene receptors was deregulated in esophageal squamous cell cancer. Up-regulation of LTB4R and down-regulation of CYSLTR2 gene expression may occur already in normal squamous esophageal epithelium of patients with esophageal cancer suggesting a potential role of these receptors in early steps of esophageal carcinogenesis. Larger studies are warranted to confirm these observations.

Steroids in pediatric eosinophilic esophagitis

Swallowed fluticasone and oral viscous budesonide are effective first-line therapies for eosinophilic esophagitis in children. Side effects are minimal without evidence of Cushing syndrome, as seen in treatment with systemic corticosteroids. New studies on alternative delivery systems and different corticosteroids (eg, ciclesonide) are encouraging. As knowledge of corticosteroids in eosinophilic esophagitis expands, newer questions continue to arise concerning dose, delivery, and choice of corticosteroids; long-term adverse effects; and maintenance therapies.

Elevated levels of leukotriene C4 synthase mRNA distinguish a subpopulation of eosinophilic oesophagitis patients

BACKGROUND

Cysteinyl leukotrienes contribute to Th2-type inflammatory immune responses. Their levels in oesophageal tissue, however, do not distinguish patients with eosinophilic oesophagitis (EoE) from controls.

OBJECTIVE

We asked whether mRNA levels of leukotriene C4 synthase (LTC4 S), a key regulator of leukotriene production, could serve as a marker for EoE.

METHODS

Digital mRNA expression profiling (nCounter(®) Technology) was performed on proximal and distal oesophageal biopsies of 30 paediatric EoE patients and 40 non-EoE controls. Expression data were confirmed with RT-qPCR. LTC4 S mRNA levels were quantified in whole blood samples. Leukotriene E4 was measured in urine.

RESULTS

LTC4 S mRNA levels were elevated in proximal (2.6-fold, P < 0.001) and distal (2.9-fold, P < 0.001) oesophageal biopsies from EoE patients. Importantly, increased LTC4 S mRNA transcripts identified a subpopulation of EoE patients (28%). This patient subgroup had higher serum IgE levels (669 U/mL vs. 106 U/mL, P = 0.01), higher mRNA transcript numbers of thymic stromal lymphopoietin (TSLP) (1.6-fold, P = 0.009) and CD4 (1.4-fold, P = 0.04) but lower IL-23 mRNA levels (0.5-fold, P = 0.04). In contrast, elevated levels of IL-23 mRNA were found in oesophageal biopsies of patients with reflux oesophagitis. LTC4 S mRNA transcripts in whole blood and urinary excretion of leukotriene E4 were similar in EoE patient subgroups and non-EoE patients.

CONCLUSION & CLINICAL RELEVANCE

Elevated oesophageal expression of LTC4 S mRNA is found in a subgroup of EoE patients, concomitant with higher serum IgE levels and an oesophageal transcriptome indicative of a more-pronounced allergic phenotype. Together with TSLP and IL-23 mRNA levels, oesophageal LTC4 S mRNA may facilitate diagnosis of an EoE subpopulation for personalized therapy.

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.

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

OBJECTIVES

Features of eosinophilic esophagitis (EoE) and gastroesophageal reflux disease (GERD) overlap. We aimed to determine whether staining for tissue biomarkers would differentiate EoE from GERD, suggesting utility for diagnosis of EoE.

METHODS

In this case-control study, EoE patients defined by consensus guidelines were compared to GERD patients with eosinophils on esophageal biopsy. Immunohistochemistry was performed for major basic protein (MBP), eotaxin-3, leukotriene A4 hydrolase (LTA4H), and leukotriene C4 synthase (LTC4S). After masking, the maximum staining density (cells per mm(2)) was quantified for each marker and compared between groups. Receiver operator characteristic curves were constructed, and the area under the curve (AUC) calculated to assess the diagnostic utility of each of the biomarkers alone and in combination with eosinophil counts.

RESULTS

There were 51 EoE cases (mean age 24; mean 143 eosinophils per high-power field (eos per h.p.f.)) and 54 GERD controls (mean age 34; mean 20 eos per h.p.f.). The MBP density was higher in EoE than in GERD (1479 vs. 59 cells per mm(2); P<0.001), as was the eotaxin-3 density (2219 vs. 479; P<0.001). There were no differences for LTA4H and LTC4S. MBP density and eosinophil count correlated (R=0.81; P<0.001); correlation with eotaxin-3 was weaker (R=0.25; P=0.01). The AUC for diagnosis of EoE was 0.96 for MBP, 0.87 for eotaxin-3, 0.58 for LTA4H, 0.66 for LTC4S, and 0.99 for the combination of MBP, eotaxin-3, and eosinophil count.

CONCLUSIONS

Patients with EoE had substantially higher levels of MBP and eotaxin-3 staining than GERD patients. These markers may have utility as a diagnostic assay for EoE.

Diagnosis and management of eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a chronic inflammatory condition characterized by esophageal dysfunction and eosinophilic infiltrate in the esophageal epithelium in the absence of other potential causes of eosinophilia. EoE is increasing in incidence and prevalence, and is a major cause of gastrointestinal morbidity among children and adults. EoE is thought to be immune mediated, with food or environmental antigens stimulating a T-helper (Th)-2 inflammatory response. An increased understanding of the pathogenesis of EoE has led to the evolution of diagnostic and treatment paradigms. We review the latest approach to diagnosis of EoE and present consensus diagnostic guidelines. We also discuss the clinical, endoscopic, and histologic features of EoE and challenges to diagnosis. Finally, we present the 3 major treatment options for EoE: pharmacologic therapy, dietary modification, and endoscopic dilation.

Eosinophilic gastrointestinal diseases: review and update

Eosinophilic gastrointestinal disorders (EGIDs) are a progressively more frequent diverse group of intestinal diseases. The intention of this paper is to present the newest developments in the care of patients with EGIDs and to sum up a rising literature defining the clinical features and mechanistic elements of eosinophils and their intricate associations with the gastrointestinal tract. Clinicians ought to stay sensitive to EGIDs as a diagnostic likelihood for patients with general gastrointestinal symptoms. Further research is warranted to establish various methods leading to dysfunction coupled with eosinophilic gastrointestinal inflammation.

Montelukast was inefficient in maintaining steroid-induced remission in adult eosinophilic esophagitis

BACKGROUND AND AIMS

Leukotriene D4 is produced by and functions as a chemotactic factor for eosinophils. Eosinophilic esophagitis (EoE) is characterized by esophageal eosinophilic infiltration, determining structural changes and dismotility symptoms. Montelukast, a selective leukotriene D4 receptor antagonist, has gained increasing consideration as a therapeutic agent for EoE. However, limited available information has shown that montelukast is not effective in reducing eosinophilic infiltration. Our paper aims at evaluating whether montelukast could be consider as a steroid-sparing therapy by assessing its efficacy in maintaining both clinical and histopathological remission achieved after topical corticosteroids in adult EoE patients.

METHODS

Eleven consecutively diagnosed adult EoE patients were prospectively studied. Esophageal biopsies were obtained before and after a 6-month treatment with fluticasone propionate 400 μg/twice a day. Immediately after that, montelukast 10 mg/day was instituted. A new endoscopy was foreseen after a new 3-month period, or as soon as the patients presented esophageal symptoms. Symptoms were assessed by using a questionnaire before and after fluticasone propionate treatment and after montelukast therapy.

RESULTS

Eosinophils density into the esophageal epithelium and lamina propria was significantly reduced after a 6-month treatment with topical steroids (P = 0.003) and increased to levels similar to baseline level into the first 3 months after treatment with montelukast. Baseline symptom scores significantly decreased after treatment with topical steroids (P = 0.003) and increased again after montelukast therapy, but baseline levels improved.

CONCLUSIONS

Montelukast was not efficient in maintaining the histopathological or clinical response achieved by topical steroids in adult EoE patients.

Observations on use of montelukast in pediatric eosinophilic esophagitis: insights for the future

Eosinophilic esophagitis is characterized by dense infiltration of the esophageal epithelium with eosinophils, typically accompanied by dysphagia. Effective therapies include the use of topical and systemic steroids as well as elimination diets. No previous reports have described the use of montelukast in the management of pediatric eosinophilic esophagitis. We retrospectively reviewed the charts of all patients with eosinophilic esophagitis followed in our pediatric center between 2000 and 2009. Those treated with montelukast were studied in detail. Study outcome was clinical response rate, defined by symptom (not histologic) improvement. Twenty-one patients with eosinophilic esophagitis were identified. Eight patients were maintained on montelukast (range 4-10 mg daily) after confirming the diagnosis of eosinophilic esophagitis histologically and failing to respond to a trial of proton pump inhibitor therapy. Three of eight patients had a clinical response (one had complete response and two with partial response) that could be attributed to montelukast. Four other patients responded clinically, but other therapies were concomitantly implemented. No side effects were reported with montelukast treatment with a mean follow-up duration of 32 months. Five patients had remained on montelukast therapy at the time of the final follow-up. Montelukast has minimal risk of adverse reactions compared with steroid therapy and may offer clinical relief in a small subset of children with eosinophilic esophagitis. Histologic response could not be verified in this study. Prospective studies, using higher montelukast doses, may potentially play a role and should be considered for future investigation.

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.

[Eosinophilic esophagitis. Clinical presentation, allergology and treatment: a series of 22 children]

BACKGROUND AND AIMS

Eosinophilic esophagitis (EE) is a disorder characterized by severe eosinophilic infiltration of the esophagus, with dysphagia and gastroesophageal reflux disease (GERD) symptoms unresponsive to acid blockade therapy but responsive to the removal of dietary antigens. We report information relating to children diagnosed with EE in Nice, France, over a 6-year period.

PATIENTS AND METHODS

We conducted a retrospective study between January 1, 2004, and July 31, 2009, evaluating all children diagnosed with EE. Clinical and demographic data, endoscopic and histological findings, allergology data, and results of treatment were collected and evaluated.

RESULTS

A total of 22 patients, 19 males, median age 9.5 years (range: 0.8-19 years) were reviewed: 7 presented isolated dysphagia, 6 presented GERD symptoms, and 9 both dysphagia and GERD symptoms. Endoscopically, 14 had multiple esophageal white plaques, 7 had linear furrowing, 5 had circular "tracheal" rings, and 5 esophageal narrowing. The median number of esophageal eosinophils/high power field (×400) was 30 (range: 15-80). Eosinophils were localized in the distal, middle, and upper esophagus. Immunoallergy analysis findings were: high peripheral eosinophil count (74%), high total IgE level (65%), high eosinophil cationic protein (ECP) level (90%) with a median value of 69.5 μg/l and high urinary leukotriene E4 (88%). Food antigen sensitization was positive in skin-prick testing in 11 of 18 and in atopy-patch testing in 9 of 17. Dietary restriction improved clinical symptoms in 5 of 10 and local corticotherapy with viscous budesonide improved clinical symptoms in 9 out of 10.

CONCLUSION

EE diagnosis must be considered in children with dysphagia or GERD who do not respond to acid blockade therapy. ECP may be used to guide diagnosis. Local corticotherapy is effective.

Treatment of eosinophilic esophagitis: how should we manage the disease?

Eosinophilic esophagitis (EE) is a chronic clinicopathologic syndrome and is the latest inflammatory disease of the esophagus described in literature. It seems to have a multifactorial etiology. Its causes include exposure to food or airborne allergens that affect individuals who may be genetically predisposed and exposure to the acid could also modulate the inflammatory response at esophageal level. However, we currently do not know how each of these possible etiologic factors contribute to the development of the disease that is essential to define specific treatment. We have used 3 different therapeutic approaches that were effective in patients with EE: various antiinflammatory drugs that are useful in treating asthma, controlling the exposure to allergens, particularly with respect to dietary changes and dilation of the esophagus. Although none of these treatments have absolute advantages, they can efficiently control the symptoms and inflammation in a large number of patients. Each treatment option should be assessed on a case-by-case basis in accordance with the experience of each center, the patients' characteristics, their sensitivity to allergens and their preferences. This article provides the latest information on the different treatment options for patients with EE, analyzing the advantages and disadvantages of each pathology and it offers practical recommendations on how to manage these patients who are being more frequently diagnosed.

The link between allergies and eosinophilic esophagitis: implications for management strategies

Eosinophilic esophagitis (EE) has an increased incidence of diagnosis similar to other atopic diseases. We present a recent literature review of the common features between atopic diseases (i.e., asthma, allergic rhinitis and atopic dermatitis) and EE. All of the disorders have allergen triggers and evidence of a possible Th2 inflammation at the site of disease. Murine models have also shown similar features with the importance of T cells and Th2 cytokines for the development of disease. The diseases share underlying inflammation with the potential for remodeling with an increase in TGF-beta expression in asthma and EE. However, differences do exist between the diseases in treatment and pathogenesis. For EE, there are two basic treatment options: avoidance of the food triggers or treatment of the eosinophilic inflammation with corticosteroids.

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.

Biomarkers for nononcologic gastrointestinal diseases

Biomarkers are objectively measured indicators of normal and abnormal biologic processes and may vary with therapeutic interventions. In the area of gastrointestinal diseases, biomarker research is primarily in the area of cancer biology. Little is known about biomarkers in connection with other gastrointestinal disorders. This article reviews biomarker data for nononcologic gastrointestinal processes with a focus on allergic disorders.

The role of mast cells in eosinophilic esophagitis

Eosinophilic esophagitis (EE) is a chronic inflammatory disease of the esophagus which is characterized by the presence of dense infiltrate of eosinophilic leukocytes restricted to this organ mucosa. Accumulating published evidence suggests a strong role of mast cells in the inflammatory infiltrate in the physiopathology of EE. We have reviewed published articles with relevant information about the presence and possible role of mast cells in EE. Although mast cells have been studied indirectly in EE, reported data allow us to confirm that the number of mast cells infiltrating the esophageal epithelium in adult and child patients with EE is higher with respect to the normal state and in gastroesophageal reflux disease. Mast cells linked to IgE, which are not found in other conditions, have been identified in EE. Despite that fact, an anaphylactic reaction history after exposure to allergens is not common in these patients. Therefore, the mast cells' function in EE could be dependent on T lymphocytes, as suggested by a mast cell gene expression analysis. Bi-directional crosstalk is established between mast cells and eosinophils, hence establishing interesting hypotheses regarding their relationship to EE physiopathology. Mast cells' function as an immune response leader seems to substitute for their effector functions in EE, while at the same time opening new research pathways for consideration of these cells as a therapeutic target in EE. However, the inefficiency of therapies that inhibit mast cell functions while they are effective in other respiratory tract diseases results in the need for specific studies to identify the real function of such complex cells in the physiopathology of EE. There is indirect proof of the role of mast cells in EE, while many doubts exist about their activation mechanism, which does not seem to be IgE-mediated. Specific approach studies are needed to clarify the function of these cells in the physiopathology of EE, which could be a possible therapeutic target.

Eosinophilic esophagitis: pathophysiology and optimal management

Eosinophilic esophagitis (EoE) is an increasingly recognized disease characterized by esophageal symptoms accompanied by increased esophageal mucosal eosinophilia. The reasons for the increasing prevalence and understanding of the pathogenesis of EoE are areas of active investigation. Food and environmental allergy, host immunologic predisposition, and interactions with gastroesophageal reflux disease have emerged as important aspects of the disease. The optimal management of EoE is controversial and evolving. Therapeutic options include medical therapy with acid suppression, corticosteroids, and biologic agents. Elimination diets and endoscopic esophageal dilation have shown effectiveness. Management strategies for individual patients range from clinical observation to multimodal therapy, depending on the clinical presentation.

Eosinophilic oesophagitis: clinical manifestations and treatment options. The role of the allergologist

Eosinophilic oesophagitis (EO) is an infrequent disorder that is currently underdiagnosed. It has been described in both adults and in children, and is more prevalent among males. The etiology of EO is not clear, though atopy has been suggested as playing an important role in the development of the disease. The clinical presentation of EO is varied, and a differential diagnosis with other digestive tract disorders is required particularly gastro-oesophageal re-flux. Dysphagia and food bolus impactation within the oesophagus are the most characteristic symptoms. Diagnostic confirmation is obtained from multiple oesophageal biopsy, with the detection in some sample or samples of over 15 eosinophils per high-magnification microscopic field. An allergological study is needed to evaluate the existence of allergens (perennial or seasonal environmental allergens and food allergens) responsible for the eosinophilic infiltration found at oesophageal level. There is no specific treatment for EO, and topical corticosteroids (swallowed) are currently the pharmacological treatment of choice. Dietary therapy in children with food allergy as the causal factor may prove effective, though the existence of polysensitisation complicates the correct implementation of such treatment. Oesophageal dilatation is reserved for cases with severe dysphagia, and is not without complications. Treatment with anti-IL-5, antileukotrienes, azathioprine, 6-mercaptopurine, anti-IgE, etc., could constitute alternatives to topical corticosteroids, although information is still lacking on their long-term safety and efficacy in the paediatric population.

Chemotactic factors associated with eosinophilic gastrointestinal diseases

The gastrointestinal (GI) tract is in constant negotiation with the microbial flora present in the lumen. Resident hematopoietic cells (ie, lymphocytes, mast cells, and eosinophils) are part of this ongoing and silent homeostatic battle. Eosinophilic GI diseases are characterized by an increased number of eosinophil infiltrates with no identified cause. This article describes the past and present knowledge regarding the chemotactic factors involved in GI eosinophilia.

Eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a disease based on a clinicopathologic diagnosis that involves a localized eosinophilic inflammation of the esophagus. A significant increase in the diagnosis of pediatric EoE has occurred over the past 10 years not only due to a greater recognition of the disease among gastroenterologists, allergists, and pathologists but also secondary to an increased incidence of the disease. EoE is defined by the presence of 15 or more esophageal eosinophils per high-power field isolated to the esophagus associated with clinical symptoms that do not respond to acid suppression therapy. Although the exact mechanism of EoE is unknown, food allergens are thought to have an important role. Effective treatment options include dietary restrictions and various steroid formulations.

Treatment of eosinophilic esophagitis: overview, current limitations, and future direction

Eosinophilic esophagitis (EE) is an increasingly recognized syndrome presenting with upper gastrointestinal (UGI) symptoms in association with hypereosinophilia (>15 eosinophils/HPF) on esophageal mucosal biopsies. The pathogenesis is unknown, but the candidate etiologies include food and aeroallergen hypersensitivity and an unusual presentation of gastroesophageal reflux disease. This review will highlight the treatments of EE in children and adults. Current treatments are controversial, few data are available in adults, and long-term studies are almost nonexistent. We outline the limitations in the current studies and suggest seven major issues in the study design that must be addressed in future drug trials.

Allergy and eosinophil-associated gastrointestinal disorders (EGID)

Eosinophil-associated gastrointestinal disorders (EGIDs) are characterized by an inappropriate accumulation of eosinophils within the gastrointestinal tract. The underlying etiology and pathophysiology that lead to the development of EGID are far from elucidated. However, there is growing evidence to support the role of aeroallergens and food allergens in the pathogenesis of these disorders. Recent advances have highlighted the role of Th2-driven cytokines in the development of EGID, and clinical studies have verified that children and adults with EGID often have positive skin testing to food allergens. The most common form of EGID, eosinophilic esophagitis (EE), has garnered intense investigation following an increased recognition over the past decade. Recently, there have been several important studies providing insight into both the cellular mechanisms governing EE and clinical therapies directed toward the treatment of EE. In the article herein, we will review the most recent scientific advances influencing our understanding of EGID with special emphasis on the role of allergens in the pathogenesis of EGID.

Eosinophilic esophagitis in adults

Eosinophilic esophagitis in adults is a disease characterized by eosinophilic infiltration of the esophageal mucosa and symptoms of long-standing solid food dysphagia and food impactions. First described in 1978, this syndrome is being recognized increasingly in the developed world, with multiple case series reported from the United States, Europe, and Australia during the past decade. Diagnosis requires the presence of greater than or equal to 15 eosinophils/high-power field on esophageal biopsies. Successful treatment in adults has been reported with the use of systemic and topical swallowed steroids. Endoscopic treatment has been associated with increased an risk for tears and perforations.

Idiopathic eosinophilic disorders of the gastrointestinal tract in children

Over the last decade, eosinophilic gastrointestinal diseases have emerged as increasingly recognised diseases affecting both adults and children. While the exact morbidity is uncertain, it has become evident that they carry a significant cost to affected patients. Recent investigations shed light on basic mechanisms of eosinophilic recruitment and inflammation, and suggest a critical role for Th2 cytokines, such as eotaxin, and allergen exposure in their pathogenesis. Eosinophilic oesophagitis (EO) is the best characterised of these diseases, and improved understanding of its basic biology stimulated development of new treatment regimens. Current evidence supports the use of elemental diets and systemic or topical corticosteroids to treat EO. A major clinical problem is the fact that most patients relapse when medical treatment is discontinued, thus making nutritional management an attractive long term option. Many areas remain unanswered in the management of patients with EGIDs, including identification of optimal treatment protocol, development of appropriate non-invasive monitoring, and choice of appropriate therapeutic endpoints.

Histopathologic features of eosinophilic esophagitis

The pathology of eosinophilic esophagitis (EE) when fully developed in humans is highly characteristic and readily discriminated from the histology of the normal esophagus. The histologic alterations are not pathognomonic for any of the multiple causes of EE, and the correct diagnosis can be made only if the histology is correlated with clinical findings. The histology of the normal esophagus is reviewed and contrasted with the findings in EE. The characteristic findings in EE are illustrated. Selected research in humans and animal models pertinent to EE are briefly reviewed.

Noninvasive markers of eosinophilic esophagitis

There has been an increasing awareness and recognition of eosinophilic esophagitis (EE), a chronic condition with periods of exacerbation and remission, over the last decade. The complex pathophysiology of EE and eosinophil physiology provide several candidate biomarkers that could be studied on various noninvasively obtained body specimens. This article reviews several potential noninvasive biomarkers of EE.

Pharmacologic treatment of eosinophilic esophagitis

There are several treatment options available for patients who have eosinophilic esophagitis (EE). These options include dilatation for mechanical esophageal abnormalities, pharmacologic therapy, and dietary management. Providing the appropriate therapy depends on the significance of clinical symptoms, association of abnormal anatomy, and histologic involvement of underlying the esophageal tissue. This article focuses on the pharmacotherapy of EE.

Eosinophilic esophagitis

PURPOSE OF REVIEW

Eosinophilic esophagitis is a disorder increasing in frequency that typically causes symptoms similar to those seen with gastroesophageal reflux, and is characterized by increased eosinophils isolated to the esophagus despite the use of antireflux medications. We present a review of the literature including basic science research, prevalence, clinical presentation, diagnosis, and management of eosinophilic esophagitis.

RECENT FINDINGS

Over the past few years, there has been a dramatic increase in the number of publications relating to eosinophilic esophagitis in terms of case reports, cohorts of patients, familial occurrences, pathogenesis, and treatment options. Recent work confirms the role of food allergy in many patients with eosinophilic esophagitis. Several medications, including corticosteroids [topical (swallowed) or systemic], leukotriene receptor antagonists and, most recently, biologic molecules (such as anti-IL5), have been utilized. Although eosinophilic esophagitis is treatable, it is thought to be a chronic illness that requires dietary restriction or chronic medical therapy.

SUMMARY

Eosinophilic esophagitis is being diagnosed in both children and adults with increasing frequency. Allergists, gastroenterologists, pathologists, internists, pediatricians, and otolaryngologists must not only be educated to be able to properly identify patients with eosinophilic esophagitis but also be informed about the current treatment and management of these patients.

Variability in diagnostic criteria for eosinophilic esophagitis: a systematic review

BACKGROUND

Eosinophilic esophagitis (EoE) is an emerging clinicopathologic entity defined by abnormal esophageal eosinophilic infiltration. Our understanding of this disease is hampered by the lack of a uniform diagnostic standard. The aim of this systematic review was to determine the range of diagnostic strategies and histologic criteria in the EoE literature.

METHODS

The MEDLINE-indexed literature from 1950 through December 31, 2006 was independently searched by two investigators. To identify additional relevant studies, bibliographies were hand searched, as were the published proceedings of the 2000-2006 American College of Gastroenterology and American Gastroenterological Association national meetings. Data were extracted from all human EoE case reports, case series, cross-sectional and cohort studies, and clinical trials.

RESULTS

Of 318 publications initially identified, 116 original articles, 39 abstracts, and 69 reviews were included. We found 10 different histologic definitions of EoE, ranging from 5 to 30 eosinophils per high-powered field (hpf), though 41 (35%) of the original articles did not state their diagnostic criteria. In the 13 original articles (11%) reporting an hpf area, the eosinophil density per mm(2) varied 23-fold. There was also variation in esophageal biopsy protocols, but specific protocols were reported in just 45 (39%) original articles.

CONCLUSIONS

Significant variability in diagnostic criteria for eosinophilic esophagitis exists, and in a large proportion of studies, criteria are not reported. Because of this lack of a common disease definition, conclusions drawn from the cumulative EoE literature should be viewed with caution. A consensus research-quality standard for diagnosis of eosinophilic esophagitis is needed.

Eosinophilic esophagitis in children and adults: a systematic review and consensus recommendations for diagnosis and treatment

During the last decade, clinical practice saw a rapid increase of patients with esophageal eosinophilia who were thought to have gastroesophageal reflux disease (GERD) but who did not respond to medical and/or surgical GERD management. Subsequent studies demonstrated that these patients had a "new" disease termed eosinophilic esophagitis (EE). As recognition of EE grew, so did confusion surrounding diagnostic criteria and treatment. To address these issues, a multidisciplinary task force of 31 physicians assembled with the goal of determining diagnostic criteria and making recommendations for evaluation and treatment of children and adults with suspected EE. Consensus recommendations were based upon a systematic review of the literature and expert opinion. EE is a clinicopathological disease characterized by (1) Symptoms including but not restricted to food impaction and dysphagia in adults, and feeding intolerance and GERD symptoms in children; (2) > or = 15 eosinophils/HPF; (3) Exclusion of other disorders associated with similar clinical, histological, or endoscopic features, especially GERD. (Use of high dose proton pump inhibitor treatment or normal pH monitoring). Appropriate treatments include dietary approaches based upon eliminating exposure to food allergens, or topical corticosteroids. Since EE is a relatively new disease, the intent of this report is to provide current recommendations for care of affected patients and defining gaps in knowledge for future research studies.

Upper gastrointestinal tract eosinophilic disorders: pathobiology and management

Patients with eosinophilic esophagitis present with symptoms similar to those from gastroesophageal reflux disease along with dense esophageal eosinophilia (normal gastric and duodenal biopsies) that persist despite aggressive acid blockade. The dramatic increase in prevalence of eosinophilic esophagitis over the past several years provides clinicians with a new explanation for previously unexplained dysphagia, food impaction, vomiting, and abdominal pain. As a product of this recognition, an increasing number of basic and translational studies are building a new understanding of the pathogenesis of esophageal eosinophilia. This review addresses recent studies that define clinical features, genetic predisposition, pathogenetic mechanisms, and treatment options for eosinophilic esophagitis.

Eosinophilic disorders in children

Many pediatric diseases demonstrate blood or tissue eosinophilia. Included among these disorders are common atopic diatheses such as asthma as well as the rarer conditions of hypereosinophilic syndrome and eosinophilic gastrointestinal disorders. Eosinophil trafficking and activation in target organs leads to tissue damage and ongoing reparative attempts that can ultimately result in changes in organ structure and function. Recent treatment with biologic agents such as tyrosine kinase inhibitors and anti-interleukin-5 has offered new therapeutic options in certain eosinophilic disorders. Eosinophilic disorders such as eosinophilic esophagitis are increasingly being diagnosed in children, but many lessons in disease pathogenesis, diagnosis, optimal treatment, and natural history continue to be learned.

Emerging questions regarding eosinophil's role in the esophago-gastrointestinal tract

PURPOSE OF REVIEW

Eosinophilic inflammation of the gastrointestinal tract is either increasing in frequency or being better recognized. Whichever is the case, clinical needs to meet this new challenge include establishing diagnostic criteria, identifying the natural history and determining effective, tolerable treatments.

RECENT FINDINGS

During the last 5 years, the emergence of eosinophilic esophagitis stimulated many case series; the new frontiers relate to understanding disease pathogenesis and maintenance treatments. Eosinophilic gastrointestinal diseases involving the rest of the gastrointestinal tract pose new challenges in understanding the role of eosinophils in intestinal dysmotility and protein loss.

SUMMARY

This review will focus on new clinical developments in the field of eosinophilic gastrointestinal diseases and the contribution of basic studies in understanding eosinophils impact on gastrointestinal inflammation.

Allergic eosinophilic esophagitis

Allergic eosinophilic esophagitis is an increasingly recognized disease in various parts of the world. The clinical presentation mimics other gastrointestinal diseases, especially gastroesophageal reflux disease, making endoscopic examination and histological evaluation of esophageal mucosal biopsies crucial to accurate diagnosis. The pathogenesis likely involves allergen-initiated, TH2-dependent, IL-5 mediated infiltration of eosinophilis into the esophageal mucosa. Therapies currently favored include dietary modifications and use of corticosteroids.