Eosinophilic esophagitis

Epithelial-mesenchymal transition, regulated by β-catenin and Twist, leads to esophageal wall remodeling in pediatric eosinophilic esophagitis

Eosinophilic Esophagitis (EoE) is an antigen-triggered inflammatory condition of the esophageal lining characterized by eosinophilic infiltration. EoE is associated with significant remodeling, and although this remodeling is reversed by current treatment regimens, symptoms of EoE and associated remodeling reappear upon cessation of therapies. We hypothesized that structural remodeling of cell-cell adhesion is a key factor in the pathogenesis of EoE and that epithelial to mesenchymal transition (EMT) was a viable molecular process to lead to this remodeling. Endoscopically obtained biopsy samples from 18 EoE and 18 control pediatric patients were evaluated by transmission electron microscopy to measure intercellular spaces (IS) between cells. Biopsy samples from all groups were analyzed for cellular levels of cell-cell adhesion proteins: E-cadherin, zonula occludens associated protein-1 (ZO-1), and N-cadherin. We also analyzed for cellular levels and localization two of transcription factors, Twist1 and β-catenin, that are associated with promoting EMT. The IS was significantly increased in the EoE group compared to the control. We observed a significant decrease in E-cadherin and ZO-1 levels and a concomitant increase in N-cadherin levels in EoE samples compared to control. Further, while there was no significant change in cellular levels of β-catenin, we observed an altered localization of the protein from the cell membrane in control tissue to a nuclear/perinuclear localization in EoE. We observed higher levels of the transcription factor Twist1 in the EoE group compared to normal which was localized mainly at the nucleus. Our results suggest that the integrity of normally sealed esophageal epithelia is compromised in the EoE patients compared to control subjects, and this is due to alterations in the expression of cell adhesion molecules at the esophageal epithelium. Our data also suggest that EMT, potentially regulated by transcription factors β-catenin and Twist1, may be responsible for the molecular alteration which leads to the remodeling of esophageal epithelia in EoE.

Accuracy of digital mRNA profiling of oesophageal biopsies as a novel diagnostic approach to eosinophilic oesophagitis

BACKGROUND

Quantification of tissue eosinophils remains the golden standard in diagnosing eosinophilic oesophagitis (EoE), but this approach suffers from poor specificity. It has been recognized that histopathological changes that occur in patients with EoE are associated with a disease-specific tissue transcriptome.

OBJECTIVE

We hypothesized that digital mRNA profiling targeted at a set of EoE-specific and Th2 inflammatory genes in oesophageal biopsies could help differentiate patients with EoE from those with reflux oesophagitis (RE) or normal tissue histology (NH).

METHODS

The mRNA expression levels of 79 target genes were defined in both proximal and distal biopsies of 196 patients with nCounter® (Nanostring) technology. According to clinicopathological diagnosis, these patients were grouped in a training set (35 EoE, 30 RE, 30 NH) for building of a three-class prediction model using the random forest method, and a blinded predictive set (n = 47) for model validation.

RESULTS

A diagnostic model built on ten differentially expressed genes was able to differentiate with 100% sensitivity and specificity between conditions in the training set. In a blinded predictive set, this model was able to correctly predict EoE in 14 of 18 patients in distal (sensitivity 78%, 95% CI 52-93%) and 16 of 18 patients in proximal biopsies (sensitivity 89%, 95% CI 64-98%), without false-positive diagnosis of EoE in RE or NH patients (specificity 100%, 95% CI 85-100%). Sensitivity was increased to 94% (95% CI 71-100%) when either the best predictive distal or proximal biopsy was used.

CONCLUSION AND CLINICAL RELEVANCE

We conclude that mRNA profiling of oesophageal tissue is an accurate diagnostic strategy in detecting EoE.

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.

Eosinophilic esophagitis in children needing emergency endoscopy for foreign body and food bolus impaction

OBJECTIVE

The objective of this study was to examine the prevalence of eosinophilic esophagitis (EoE) in children presenting with esophageal foreign body (FB)/food bolus impaction.

METHODS

A retrospective chart review for all children who underwent endoscopic esophageal FB extraction at the Stollery Children's Hospital between January 2005 and December 2008 was performed. The prevalence of EoE and characteristics of children who had EoE were documented.

RESULTS

A total of 140 children (mean age, 4.98 [SD, 4] years; range, 0.3-16.9 years; 81 boys) had esophageal FB/food impaction and needed endoscopic removal over the study period. Eleven children (mean age, 9.38 [SD, 5.35] years; range, 1.9-16.2 years; 8 boys) were diagnosed with EoE (8%). Seven (39%) of 18 children with food impaction were diagnosed with EoE. Four (3%) of 122 children with esophageal foreign bodies other than food had EoE.

CONCLUSIONS

Considerable number of children with esophageal FB/food bolus impaction may have EoE. Routine sampling of esophageal mucosa at different levels during esophageal FB extraction may be considered. Well-designed prospective studies with multiple-level esophageal biopsies taken from all children with FB/food impaction are needed to confirm our results.

Eosinophilic digestive diseases: eosinophilic esophagitis, gastroenteritis, and colitis

Eosinophilic digestive diseases (EDD) are relatively rare disorders associated with increased gastrointestinal eosinophilic infiltrates without any underlying primary etiology. The pathophysiology of EDD is unclear, but is suspected to be related to a hypersensitivity reaction given its correlation with other atopic disorders and clinical response to corticosteroid therapy. Given the overall relative increase of various atopic conditions, it is important for clinicians to understand the presentation and diagnosis and treatment options available. We present here a review of EDD, including the proposed pathophysiology, diagnosis and current treatment options for these disorders.

Otolaryngologists may not be doing enough to diagnose pediatric eosinophilic esophagitis

OBJECTIVE

To systematically evaluate the diagnosis of eosinophilic esophagitis (EE).

METHODS

A retrospective review of 657 patients seen at the EE center of a tertiary care children's hospital between 1994 and 2007 was performed. Charts were reviewed for the 144 patients who were also seen by the otolaryngology service.

RESULTS

One hundred forty-four patients received 193 otolaryngology-related diagnoses. Eustachian tube dysfunction (27.5%) and sleep disordered breathing (24.9%) were the most common, followed by dysphagia (13.0%), rhinosinusitis/nasal congestion (9.3%) and airway stenosis (5.2%). Seventy-nine patients (54.9%) had a pre-existing diagnosis of EE at the time of their otolaryngology consultation. Twenty-one patients (14.6%) were referred to the gastroenterology service for evaluation for EE. Forty-four patients (30.5%) remained undiagnosed. Twenty-five of these patients presented with dysphagia, 16 of whom were not previously diagnosed with EE; only 4 of these 16 patients were referred for evaluation for EE. In one case, a child with moderate sized tonsils underwent adenotonsillectomy for dysphagia and failure to thrive; this patient was diagnosed with EE 1 month post-operatively.

CONCLUSIONS

Twenty percent of patients with EE may require care by an otolaryngologist for a myriad of complaints. Even experienced pediatric otolaryngologists may not recognize this condition. Otolaryngologists should consider EE in patients presenting with dysphagia. A careful gastroenterology review of symptoms may also allow otolaryngologists to identify EE in patients with allergy mediated nasal complaints, or laryngeal/airway disorders.

Eosinophilic gastroenteritis: a review

Eosinophilic gastroenteritis is a clinicopathological disease affecting both children and adults that is characterized by patchy or diffuse eosinophilic infiltration of the gastrointestinal tract with variable resultant clinical gastrointestinal manifestations. The eosinophil, eotaxin, and Th-2 cytokines are important in pathogenesis of this disease entity. It may be confused with parasitic and bacterial infections (including Helicobacter pylori), inflammatory bowel disease, hypereosinophilic syndrome, myeloproliferative disorders, periarteritis, allergic vasculitis, scleroderma, drug injury, and drug hypersensivity. Obtaining the correct diagnosis is important, and a pathologist usually makes this distinction. Effective treatments include systemic/topical corticosteroids, specific food elimination or an elemental diet, certain drugs, and even surgery. A variety of new therapeutic approaches are now under trial.

Eosinophilic esophagitis: a case report. Effective treatment with systemic corticosteroids for the relapse of the disease

We report on a case of eosinophilic esophagitis in a 33-year-old Japanese woman who visited our hospital with dysphagia and esophageal food impaction in April 2006. She had had the same symptoms in May 2005, and, by endoscopic and histologic examination, she was diagnosed with eosinophilic esophagitis. Biopsy specimens from multiple locations in the esophageal mucosa had shown remarkable infiltration of eosinophils, more than 20 eosinophils per high-power field in squamous mucosa, and she had been treated with Th2 cytokine antagonist and proton pump inhibitor at the time. Her symptoms had not improved, but she had received no further medical treatment. In 2006, upper gastrointestinal endoscopy showed edematous whitish esophageal mucosa, multiple ulcerations with whitish exudates on their surfaces, and white plaques. Biopsy specimens showed the same change as before, and corticosteroid (prednisolone 20 mg/day) was administered orally. After 2 weeks of corticosteroid therapy, her symptom had effectively improved. Endoscopy after 15 weeks of the therapy revealed remarkable improvement, and biopsy specimens from esophageal mucosa revealed the disappearance of the eosinophil infiltrates. We report on a case of eosinophilic esophagitis effectively treated with systemic corticosteroids. Eosinophilic esophagitis has, as yet, no standardized treatment. However, wider recognition of its features on endoscopy may reveal more cases, thereby increasing our understanding of this disease, and will provide new therapeutic possibilities.