Summary: Background: Proton pump inhibitors (PPIs) are the most commonly used first‐line therapy for patients with eosinophilic oesophagitis (EoE). However, many aspects related to PPIs in EoE are still unknown.Aims: To assess the effectiveness of PPI therapy for EoE in real‐world practice.Methods: This cross‐sectional study collected data on PPI efficacy from the multicentre EoE CONNECT database. Clinical remission was defined as a decrease of ≥50% in dysphagia symptom score; histological remission was defined as a peak eosinophil count below 15 eosinophils per high‐power field. Factors associated with effectiveness of PPI therapy were identified by binary logistic regression multivariate analyses.Results: Overall, 630 patients (76 children) received PPI as initial therapy (n = 600) or after failure to respond to other therapies (n = 30). PPI therapy achieved eosinophil density below 15 eosinophils per high‐power field in 48.8% and a decreased symptom score in 71.0% of patients. More EoE patients with an inflammatory rather than stricturing phenotype accomplished clinico‐histological remission after PPI therapy (OR 3.7; 95% CI, 1.4‐9.5); as well as those who prolonged treatment length from 8 to 12 weeks (OR 2.7; 95% CI, 1.3‐5.3). After achieving clinico‐histological remission of EoE, PPI dosage reduction was effectively maintained in 69.9% of patients, but tended to be less effective among those with a stricturing phenotype.Conclusions: Inflammatory EoE phenotype and treatment duration up to 12 weeks correlated with greater chance for inducing remission of EoE. A stricturing phenotype decreased response rates to PPI therapy both initially and in the long term.

Background: Poor adherence to clinical practice guidelines for eosinophilic esophagitis (EoE) has been described and the diagnostic delay of the disease continues to be unacceptable in many settings.Objective: To analyze the impact of improved knowledge provided by the successive international clinical practice guidelines on reducing diagnostic delay and improving the diagnostic process for European patients with EoE.Methods: Cross‐sectional analysis of the EoE CONNECT registry based on clinical practice. Time periods defined by the publication dates of four major sets of guidelines over 10 years were considered. Patients were grouped per time period according to date of symptom onset.Results: Data from 1,132 patients was analyzed and median (IQR) diagnostic delay in the whole series was 2.1 (0.7‐6.2) years. This gradually decreased over time with subsequent release of new guidelines (p < 0.001), from 12.7 years up to 2007 to 0.7 years after 2017. The proportion of patients with stricturing of mixed phenotypes at the point of EoE diagnosis also decreased over time (41.3% vs. 16%; p < 0.001), as did EREFS scores. The fibrotic sub‐score decreased from a median (IQR) of 2 (1‐2) to 0 (0‐1) when patients whose symptoms started up to 2007 and after 2017 were compared (p < 0.001). In parallel, symptoms measured with the Dysphagia Symptoms Score reduced significantly when patients with symptoms starting before 2007 and after 2012 were compared. A reduction in the number of endoscopies patients underwent before the one that achieved an EoE diagnosis, and the use of allergy testing as part of the diagnostic workout of EoE, also reduced significantly over time (p = 0.010 and p < 0.001, respectively).Conclusion: The diagnostic work‐up of EoE patients improved substantially over time at the European sites contributing to EoE CONNECT, with a dramatic reduction in diagnostic delay.

Background: Swallowed topical corticosteroids (tC) are common therapy for patients with eosinophilic esophagitis (EoE). Widely heterogeneous results have occurred due to their active ingredients, formulations and doses.Objective: To assess the effectiveness of topical corticosteroid therapy for EoE in real‐world practice.Methods: Cross‐sectional study analysis of the multicentre EoE CONNECT registry. Clinical remission was defined as a decrease of ≥50% in dysphagia symptom scores; histological remission was defined as a peak eosinophil count below 15 per high‐power field. The effectiveness in achieving clinico‐histological remission (CHR) was compared for the main tC formulations.Results: Overall, data on 1456 prescriptions of tC in monotherapy used in 866 individual patients were assessed. Of those, 904 prescriptions with data on formulation were employed for the induction of remission; 234 reduced a previously effective dose for maintenance. Fluticasone propionate formulations dominated the first‐line treatment, while budesonide was more common in later therapies. A swallowed nasal drop suspension was the most common formulation of fluticasone propionate. Doses ≥0.8 mg/day provided a 65% CHR rate and were superior to lower doses. Oral viscous solution prepared by a pharmacist was the most common prescription of budesonide; 4 mg/day provided no benefit over 2 mg/day (CHR rated being 72% and 80%, respectively). A multivariate analysis revealed budesonide orodispersible tablets as the most effective therapy (OR 18.9, p < 0.001); use of higher doses (OR 4.3, p = 0.03) and lower symptom scores (OR 0.9, p = 0.01) were also determinants of effectiveness.Conclusion: Reduced symptom severity, use of high doses, and use of budesonide orodispersible tablets particularly were all independent predictors of tC effectiveness.

Background: Eosinophilic esophagitis (EoE) is a chronic non‐IgE‐mediated allergic disease of the esophagus. An unbiased proteomics approach was performed to investigate pathophysiological changes in esophageal epithelium. Additionally, an RNAseq‐based transcriptomic analysis in paired samples was also carried out.Methods: Total proteins were purified from esophageal endoscopic biopsies in a cohort of adult EoE patients (n = 25) and healthy esophagus controls (n = 10). Differentially accumulated (DA) proteins in EoE patients compared to control tissues were characterized to identify altered biological processes and signaling pathways. Results were also compared with a quantitative proteome dataset of the human esophageal mucosa. Next, results were contrasted with those obtained after RNAseq analysis in paired samples. Finally, we matched up protein expression with two EoE‐specific mRNA panels (EDP and Eso‐EoE panel).Results: A total of 1667 proteins were identified, of which 363 were DA in EoE. RNA sequencing in paired samples identified 1993 differentially expressed (DE) genes. Total RNA and protein levels positively correlated, especially in DE mRNA‐proteins pairs. Pathway analysis of these proteins in EoE showed alterations in immune and inflammatory responses for the upregulated proteins, and in epithelial differentiation, cornification and keratinization in those downregulated. Interestingly, a set of DA proteins, including eosinophil‐related and secreted proteins, were not detected at the mRNA level. Protein expression positively correlated with EDP and Eso‐EoE, and corresponded with the most abundant proteins of the human esophageal proteome.Conclusions: We unraveled for the first time key proteomic features involved in EoE pathogenesis. An integrative analysis of transcriptomic and proteomic datasets provides a deeper insight than transcriptomic alone into understanding complex disease mechanisms.

Background: Eosinophilic esophagitis (EoE) predominantly affects males across all ages; however, little is known about sex differences for other aspects of EoE. Objective: To investigate associations between sex and clinical presentation, endoscopic features, treatment choice and response in EoE patients in real‐world practice. Methods: Cross‐sectional analysis of the multicenter EoE CONNECT registry. The independent contribution of patients' sex and other relevant variables were statistically assessed by multivariate models. Results: A total of 2976 patients (76% male) were evaluated. Males were diagnosed at a younger age compared to females (32.7 ± 14.8 vs. 34.8 ± 15.6 years, respectively; p = 0.002) with similar diagnostic delay. EoE symptoms varied significantly between sexes, with food impaction predominating in males and dysphagia, heartburn, regurgitation and abdominal and epigastric pain in females. However, female sex contributed to higher symptom severity at diagnosis as measured with Dysphagia Symptom Score ( R ² = 0.57; p = 0.013) and presented higher peak eosinophil count in esophageal biopsies ( p = 0.005). Males showed increased risk of stricturing or mixed phenotypes (adjusted OR 1.43, 95%CI:1.05–1.96; p = 0.024). No association was found between patients’ sex and first‐line treatment modality: proton pump inhibitors (PPI) were preferred over topical corticosteroids in patients with inflammatory phenotypes instead of stricturing or mixed phenotypes, and in patients who did not present food impaction. Both topical corticosteroids and dietary interventions were preferred over PPI in pediatric patients regardless of sex. Conclusions: Sex is associated with clinical and phenotypical presentation of EoE at diagnosis, with more fibrotic findings in males but higher symptom score in females.

This study compared short-term effectiveness of proton pump inhibitors (PPI), swallowed topical corticosteroids (STC), and dietary therapies in reversing clinical and histological features in pediatric patients with eosinophilic esophagitits (EoE). Determinants for treatment choice and PPI therapy effectiveness were also assessed. A cross-sectional study analysis of patients under 18 years old recruited onto the multicenter EoE CONNECT registry was performed. Clinico-histological response was defined as symptomatic improvement plus a peak eosinophil count below 15 per high-power field after treatment. Effectiveness of first-line options used in monotherapy was compared. Overall, 393 patients (64% adolescents) receiving PPI, STC, or dietary monotherapy to induce EoE remission were identified. PPI was the preferred option (71.5%), despite STC providing the highest clinico-histological response rates (66%) compared to PPI (44%) and diet (42%). Logistic regression identified fibrotic features and recruitment at Italian sites independently associated to first-line STC treatment; age under 12 associated to dietary therapy over other options. Analysis of 262 patients in whom PPI effectiveness was evaluated after median (IQR) 96 (70–145) days showed that this effectiveness was significantly associated with management at pediatric facilities and use of high PPI doses. Among PPI responders, decrease in rings and structures in endoscopy from baseline was documented, with EREFS fibrotic subscore for rings also decreasing among responders (0.27 ± 0.63 vs. 0.05 ± 0.22, p < 0.001). Conclusion: Initial therapy choice for EoE depends on endoscopic phenotype, patient’s age, and patients’ origin. High PPI doses and treatment in pediatric facilities significantly determined effectiveness, and reversed fibrotic endoscopic features among responders. What is Known:• Proton pump inhibitors are widely used to induce and maintain remission in EoE in real practice, despite other first-line alternative therapies possibly providing higher effectiveness. What is New:• Proton pump inhibitors represent up to two-thirds of first-line monotherapies used to induce EoE remission in pediatric and adolescent patients with EoE. The choice of STC as first-line treatment for EoE was significantly associated with fibrotic features at baseline endoscopy and recruitment in Italian centers; age less than 12 years was associated with dietary therapy.• PPI effectiveness was found to be determined by use of high doses, attendance at pediatric facilities, presenting inflammatory instead of fibrotic or mixed phenotypes, and younger age. Among responders, PPI therapy reversed both inflammatory and fibrotic features of EoE after short-term treatment.