Improvement in Esophageal Distensibility in Response to Medical and Diet Therapy in Eosinophilic Esophagitis

Eosinophilic oesophagitis in adults: from symptoms to therapeutic options

Eosinophilic oesophagitis (EoE) is a chronic and progressive immune-mediated condition, typically affecting young atopic male adults and potentially leads to organ dysfunction and fibrosis. The clinical spectrum widely varies -from non-troublesome dysphagia to food impaction- and hence the rate of misdiagnosis and diagnostic delay are high, especially when presenting with minor symptoms, such as heartburn and acid regurgitation. There have been several major therapeutic breakthroughs for the management of EoE in recent years. Highly effective conventional agents with oesophagus-specific formulations (i.e. orodispersible budesonide) and a biological agent (i.e. dupilumab) now have a formal indication. Oesophageal dilation may be indicated in case of strictures, which are more common in longstanding and untreated disease. Therefore, the early diagnosis of this disorder and specialist referral is if of great importance. The evaluation of alarm signs and typical presentation patterns should allow a more straightforward recognition. The emergency and internal medicine doctors should actively be involved in this process and take part to the multidisciplinary care of patients with EoE, to allow better patient care and clinical outcomes.

Esophageal remodeling in eosinophilic esophagitis

PURPOSE OF REVIEW

Eosinophilic esophagitis (EoE) is a Th2 immune/antigen-mediated disorder characterized by esophageal dysfunction and eosinophilic inflammation. Worsening dysphagia and food impactions are significant complications associated with esophageal remodeling and fibrostenotic disease. This review highlights the most recent research findings pertaining to mechanisms of sub-epithelial fibrosis in EoE, current diagnostic tools, and therapeutic approaches.

RECENT FINDINGS

Recent studies leveraging publicly available single cell sequencing databases and comparative proteomics have furthered our understanding of the mechanisms mediating fibrosis. Fibroblast crosstalk with the extracellular matrix and with epithelial, endothelial, and T cells have been implicated, with the likely existence of multiple fibroblast sub-types. Accurate diagnosis of remodeling with biopsies remains a challenge due to inadequate depth of sampling. Web-based tools incorporating epithelial findings show promise in predicting subepithelial fibrosis. Impedance planimetry with esophageal distensibility measurements are increasingly utilized tools to assess fibrostenotic severity. Immunostaining and luminal captured proteins associated with remodeling show promise as potential molecular markers of fibrosis. Anti-inflammatory therapy may improve esophageal fibrosis and distensibility, although specific fibrosis-targeted therapy is lacking.

SUMMARY

Recent studies highlight novel mechanisms of fibrosis in EoE. Improved understanding of these mechanisms may lead to novel diagnostic strategies and therapies, and thereby inform treatment decisions.

Monitoring and modulating the trajectory of eosinophilic esophagitis

Current treatments of eosinophilic esophagitis (EoE) aim to eliminate esophageal mucosal inflammation and attenuate, stabilize, or reverse stricture formation. However, our ability to study the long-term course of esophageal strictures in patients with EoE is hampered by the short-term existence of this disease. It is unclear to what degree of control of inflammation is needed to prevent stricture formation. Additionally, identified phenotypes of EoE may ultimately dictate different levels of concern and time intervals for developing fibrosis. Currently, multiple methods are used to monitor patients' disease progression to fibrosis, as symptoms alone do not correlate with disease activity. Endoscopic findings and mucosal histology are used to monitor disease activity, but these focus on improvements in inflammation with inconsistent evaluation of underlying fibrosis. The use of functional lumen impedance planimetry, barium esophagraphy, and endoscopic ultrasound continues to expand in EoE. The rapid advancements in EoE have led to an armamentarium of measuring tools and therapies that holistically characterize disease severity and response to therapy. Nevertheless, our ability to evaluate gross esophageal fibrosis and stricture formation from a transmural rather than mucosal view should be a focus of future investigations because it is essential to monitoring and modulating the trajectory of EoE.

The 1st EoETALY Consensus on the Diagnosis and Management of Eosinophilic Esophagitis - Definition, Clinical Presentation and Diagnosis

Eosinophilic esophagitis (EoE) is a chronic type 2-mediated inflammatory disease of the esophagus that represents the most common eosinophilic gastrointestinal disease. Experts in the field of EoE across Italy (i.e., EoETALY Consensus Group) including gastroenterologists, endoscopists, allergologists/immunologists, and paediatricians conducted a Delphi process to develop updated consensus statements for the management of patients with EoE and update the previous position paper of the Italian Society of Gastroenterology (SIGE) in light of recent evidence. Grading of the strength and quality of the evidence of the recommendations was performed using accepted GRADE criteria. The guideline is divided in two documents: Part 1 includes three chapters, namely 1) definition, epidemiology, and pathogenesis; 2) clinical presentation and natural history, and 3) diagnosis, while Part 2 includes two chapters: 4) treatment and 5) monitoring and follow-up. This document has received the endorsement of three Italian national societies including the SIGE, the Italian Society of Neurogastroenterology and Motility (SINGEM), and the Italian Society of Allergology, Asthma, and Clinical Immunology (SIAAIC). With regards to patients' involvement, these guidelines involved the contribution of members of ESEO Italia, the Italian Association of Families Against EoE.

Clinical Evaluation of the Adult with Eosinophilic Esophagitis

Adult patients with eosinophilic esophagitis (EoE) typically present with a history of dysphagia for solids, sometimes with additional reflux-like pain and a history of prior food impactions. In contrast to these alarming symptoms, the general appearance and physical examination of adult patients with EoE is in line with apparently healthy individuals. Therefore, the diagnosis is based on a history of solid-food dysphagia and eosinophilic tissue infiltration. Importantly, the increasing prevalence of EoE variants, that is, typical EoE symptoms in the absence of a relevant eosinophilia, and several studies with eosinophil-targeting drugs, call the pathogenic role of eosinophils into question.

Composite score of physiomechanical esophageal function using functional lumen imaging probe panometry in eosinophilic esophagitis

BACKGROUND AND AIMS

The evaluation provided by functional lumen imaging probe (FLIP) panometry includes esophageal distensibility/compliance (mechanics) of the esophageal body and esophagogastric junction (EGJ) and esophageal motility (secondary peristalsis). We developed a composite score using these parameters to characterize physiomechanical function in patients with eosinophilic esophagitis (EoE).

METHODS

Two hundred fifteen adult patients with EoE who completed FLIP panometry during sedated endoscopy with esophageal biopsy sampling were included. FLIP metrics of esophageal body Compliance, Contractile response, Distensibility plateau, and maximum EGJ Diameter (C2D2) were scored as 0 for normal versus 1 or 2 for increasing degree of abnormality. Scores were summed to calculate the composite C2D2 score.

RESULTS

The C2D2 score had a significant positive correlation with mucosal eosinophil count (ρ = .241) and total Endoscopic EoE Reference Score (ρ = .467). Among 46 patients off treatment at the baseline evaluation, future proton pump inhibitor (PPI) responders (ie, achieved mucosal eosinophil count <15 per high-powered field after PPI treatment) had lower C2D2 scores than PPI nonresponders (median, 2 [interquartile range, 1-3] vs 4 [interquartile range, 2-6], respectively; P = .003). A regression model (that controlled for age, sex, and baseline eosinophil count) showed a C2D2 score ≤3 had an odds ratio of 14.5 (95% confidence interval, 2.6-85) to predict future PPI response. However, total Endoscopic EoE Reference Scores (P = .142) and baseline eosinophil count (P = .480) did not differ between PPI responders and PPI nonresponders.

CONCLUSIONS

This composite score of FLIP panometry metrics, the C2D2 score, may facilitate characterizing physiomechanical function in EoE and serve as an objective outcome measure.

The Severity of Reduced Esophageal Distensibility Parallels Eosinophilic Esophagitis Disease Duration

BACKGROUND & AIMS

Chronic inflammation of eosinophilic esophagitis (EoE) results in progressive, fibrostenotic remodeling of the esophageal wall. This study aimed to demonstrate objective changes in esophageal distensibility relative to duration of EoE disease using a functional lumen imaging probe (FLIP).

METHODS

Adult patients with EoE who completed a 16-cm FLIP protocol during endoscopy were evaluated in a cross-sectional study. FLIP analysis focused on distensibility plateau (DP) of the esophageal body. The time from onset of symptoms to time of endoscopy with FLIP was assessed, as was time from symptom onset to EoE diagnosis (ie, diagnostic delay).

RESULTS

A total of 171 patients (mean age 38 ± 12 years; 31% female) were included; the median symptom duration was 8 (interquartile range, 3-15) years and diagnostic delay was 4 (interquartile range, 1-12) years. At the time of endoscopy with FLIP, there were 54 patients (39%) in histologic remission (<15 eosinophils per high-power field [eos/hpf]). Symptom duration and diagnostic delay were negatively correlated with DP (rho = -0.326 and -0.309; P values < .001). Abnormal esophageal distensibility (DP ≤17 mm) was more prevalent with increased duration of symptoms (P < .004): 23% at <5 years to 64% at ≥25 years. When stratifying the cohort based on mucosal eosinophil density, patients with ≥15 eos/hpf had significantly lower DP with greater symptom duration (P = .004), while there was not a significant difference among patients with <15 eos/hpf (P = .060).

CONCLUSIONS

Esophageal distensibility objectively measured with FLIP was reduced in EoE patients with greater symptom duration and diagnostic delay. This supports that EoE is a progressive, fibrostenotic disease and that FLIP may be a useful tool to monitor disease progression in EoE.

A New Method to Evaluate Lower Esophageal Distension Capacity in Eosinophilic Esophagitis by Using Functional Lumen Imaging Probe (EndoFLIP™)

Endoluminal functional lumen impedance planimetry (EndoFLIPTM) has become the gold standard to evaluate esophageal distensibility, although the study itself and its analysis present challenges. We propose here a new method to assess lower esophageal distension capacity that overcomes several limitations of prior approaches, including incomplete and corrupted EndoFLIPTM recordings. Esophageal distension capacity was evaluated with a 16-channel EndoFLIPTM in 10 controls and 14 patients with eosinophilic esophagitis (EoE). Controls were evaluated once. EoE patients were evaluated at baseline and after at least six weeks of treatment with orodispersible budesonide tablets, 1 mg bd. Balloon volumes were increased by 5 mL stepwise, either reaching a maximum volume of 60 mL or a maximum balloon pressure of 60 mmHg. Recordings were analyzed with a homemade R script. The mean esophageal diameter at 60 mL, D (60 mL), was calculated or extrapolated depending on whether the 60 mL volume was reached. By fitting a Michaelis-Menten curve across all measured diameters throughout all constant volume steps, the mean D (60 mL) was estimated. For control subjects, the mean ± SD value of D (60 mL) was 17.08 ± 1.69 mm, and for EoE patients at baseline, D (60 mL) was 14.51 ± 2.68 mm. After six weeks of treatment of EoE patients, D (60 mL) significantly increased to 16.22 ± 1.86 mm (paired Wilcoxon signed test: p = 0.0052), although the values for control subjects were not reached. The estimated mean esophageal diameter at 60 mL is a good proxy for esophageal distension capacity, which correlates with clinical outcomes in EoE. The method presented in this study overcomes difficulties encountered during the standard measurement protocol, allowing the analysis of recordings from incomplete and corrupted registries.

Fibrous Remodeling in Eosinophilic Esophagitis: Clinical Facts and Pathophysiological Uncertainties

Eosinophilic esophagitis (EoE) is a chronic, progressive, type 2 inflammatory disease with increasing global prevalence. An eosinophil-predominant inflammation that permeates the epithelium and deeper esophageal layers characterizes the disease. Several cytokines, mainly derived from inflammatory T-helper 2 (Th2) cells and epithelial cells, are involved in perpetuating inflammatory responses by increasing surface permeability and promoting tissue remodeling characterized by epithelial-mesenchymal transition (EMT) and collagen deposition. This leads to esophageal strictures and narrow caliber esophagi, which are proportional a patient's age and untreated disease length. Pathophysiological mechanisms leading to EoE have been described in recent years, and transforming growth factor beta (TGF)-beta have been involved in fibrotic phenomena in EoE. However, evidence on the dependence of these phenomena on TGF-beta is scarce and contradictory. This review provides state-of-the art knowledge on intimate mechanisms of esophageal fibrosis in EoE and its clinical consequences.

The Role of Esophageal Physiologic Tests in Eosinophilic Esophagitis

Background

In patients with eosinophilic esophagitis (EoE), the correlation between symptoms of esophageal dysfunction and endoscopic and histologic disease activity is generally poor and probably related to multiple causes such as esophageal remodeling processes that might go undetected using endoscopy and histology as well as esophageal hypervigilance and symptom-specific anxiety. Hence, there is a need for a holistic management of patients that goes beyond the control of eosinophilia and symptoms.

Summary and Key Messages

Physiological esophageal testing using high-resolution manometry, functional lumen imaging probe, pH-impedance, wireless pH monitoring, and mucosal impedance may unveil the effects of chronic transmural fibro-inflammatory changes of the esophageal wall as well as esophageal hypervigilance, thereby assisting to phenotype patients, predict therapeutic response to therapy, and identify motility disorders that may need a specific targeted therapy to ameliorate patients' outcomes. This article discusses the role of functional esophageal examinations in the diagnosis and management of EoE.

Th2 cytokine signaling through IL-4Rα increases eotaxin-3 secretion and tension in human esophageal smooth muscle

In esophageal epithelial cells in eosinophilic esophagitis (EoE), Th2 cytokines (IL-4, IL-13) signal through IL-4Rα, activating JAK to increase eotaxin-3 secretion, which draws eosinophils into the mucosa. We explored whether Th2 cytokines also might stimulate eotaxin-3 secretion and increase tension in esophageal smooth muscle (ESM), which might impair esophageal distensibility, and whether those events could be blocked by proton pump inhibitors (PPIs) or agents that disrupt IL-4Rα signaling. We established human ESM cell cultures from organ donors, characterizing Th2 cytokine receptor and P-type ATPase expression by qPCR. We measured Th2 cytokine-stimulated eotaxin-3 secretion by enzyme-linked immunosorbent assay (ELISA) and ESM cell tension by gel contraction assay, before and after treatment with omeprazole, ruxolitinib (JAK inhibitor), or IL-4Rα blocking antibody. CPI-17 (inhibitor of a muscle-relaxing enzyme) effects were studied with CPI-17 knockdown by siRNA or CPI-17 phospho(T38A)-mutant overexpression. ESM cells expressed IL-4Rα and IL-13Rα1 but only minimal H+-K+-ATPase mRNA. Th2 cytokines increased ESM eotaxin-3 secretion and tension, effects blocked by ruxolitinib and IL-4Rα blocking antibody but not consistently blocked by omeprazole. IL-13 increased ESM tension by increasing CPI-17 expression and phosphorylation, effects blocked by CPI-17 knockdown. Blocking IL-4Rα decreased IL-13-stimulated eotaxin-3 secretion, CPI-17 expression, and tension in ESM. Th2 cytokines increase ESM eotaxin-3 secretion and tension via IL-4Rα signaling that activates CPI-17. Omeprazole does not reliably inhibit this process, but IL-4Rα blocking antibody does. This suggests that ESM eosinophilia and impaired esophageal distensibility might persist despite elimination of mucosal eosinophils by PPIs, and IL-4Rα blocking agents might be especially useful in this circumstance.NEW & NOTEWORTHY We have found that Th2 cytokines increase eotaxin-3 secretion and tension in esophageal smooth muscle (ESM) cells via IL-4Rα signaling. Unlike esophageal epithelial cells, ESM cells do not express H+-K+-ATPase, and omeprazole does not inhibit their cytokine-stimulated eotaxin-3 secretion or tension. An IL-4Rα blocking antibody reduces both eotaxin-3 secretion and tension induced by Th2 cytokines in ESM cells, suggesting that an agent such as dupilumab might be preferred for patients with EoE with esophageal muscle involvement.

Esophageal biomechanics assessed by impedance planimetry (EndoFLIPTM) in healthy subjects and in patients with eosinophilic esophagitis. Normality values

BACKGROUND

active eosinophilic esophagitis is associated with esophageal caliber, distensibility and motility changes that may be reversed with treatment.

OBJECTIVES

to study esophageal diameter, distensibility and contractility in healthy subjects compared to patients with eosinophilic esophagitis, both before and after treatment.

METHODS

a quasi-experimental study, EndoFLIP™, was used to analyze the esophageal body and esophago-gastric junction (EGJ) in all three groups, and a program was designed to obtain esophageal diameter, distensibility and contractility values.

RESULTS

ten healthy volunteers (24-61 years, six men) and nine patients with eosinophilic esophagitis (21-52 years, seven men) were included. The esophagogastric junction distensibility index was 5.07 mm2/Hg in the control subjects, 2.40 mm2/Hg in the subjects with eosinophilic esophagitis before treatment and 2.46 mm2/Hg after treatment. The distensibility plateau was 20.02 mm, 15.43 mm and 17.41 mm, respectively, and the diameter was 21.90 mm, 17.73 mm and 18.30 mm, showing significant differences (p < 0.05), except between control subjects and patients after treatment (p = 0.079). Repetitive antegrade contractions developed in 90 % of control subjects, 66.7 % of eosinophilic esophagitis patients before treatment and 88.9 % of the latter after treatment (p > 0.05).

CONCLUSIONS

esophago-gastric junction distensibility index, distensibility plateau and diameter values were higher in controls than in patients, although six weeks of treatment seems a short period to observe significant changes in esophageal biomechanics. Repetitive antegrade contractions are the predominant pattern in healthy subjects and eosinophilic esophagitis. We provide normality values for esophageal biomechanics, measured by impedance planimetry in our setting.

Inter- and intra-rater agreement of interpretation of functional lumen imaging probe in healthy subjects

BACKGROUND

The functional lumen imaging probe (FLIP) evaluates esophagogastric junction (EGJ) opening and esophageal contractility. Both post hoc and real-time analyses are possible, but reproducibility and reliability of analysis remain undefined. This study assesses inter- and intra-rater agreement of normative FLIP measurements among novice and experienced users.

METHODS

Eight motility experts from different institutions independently evaluated de-identified video recordings from 27 asymptomatic healthy subjects using FLIP. Interpretation methods simulating a post-procedure and a live procedure setting were tested. Novice FLIP users (n = 3) received training prior to post-procedure interpretation. Experienced FLIP users (n = 5) interpreted using both methods. Users recorded maximum EGJ and distal esophageal body diameter, distensive pressure, and EGJ distensibility index (EGJ-DI), at balloon fill volumes of 50-, 60-, and 70 ml, as well as repetitive antegrade contractions (RACs). Inter- and intra-rater agreements of diameters, distensive pressure and EGJ-DI were assessed by intra-class correlation coefficient (ICC) and Pearson's correlation coefficient (PCC). Percentage agreement evaluated inter- and intra-rater reliability for RACs.

KEY RESULTS

Novice and experienced users acquired normative FLIP metrics. Good-to-excellent inter- and intra-rater reliability were achieved for all variables at 60 ml balloon fill volumes. Median parameters at 60 ml balloon fill volume were as follows: EGJ-DI 5.5 mm2 /mmHg, maximum EGJ diameter 18.6 mm, distensive pressure at maximum EGJ diameter 48.1 mmHg, and distal esophageal body diameter 19.5 mm.

CONCLUSIONS AND INFERENCES

Normative FLIP parameters can be reliably extracted from FLIP videos using both real-time and post hoc analyses, with high reliability between experienced and novice users.

Current state of biologics in treating eosinophilic esophagitis

OBJECTIVE

Eosinophilic esophagitis (EoE) is a chronic, allergen-mediated, eosinophil-predominant, type 2 inflammatory disease that progresses to fibrostenosis of the esophagus if left untreated. This review focuses on biologics therapy in EoE.

DATA SOURCES

Manuscripts on EoE treatments are identified on PubMed.

STUDY SELECTIONS

Original research, randomized controlled trials, retrospective studies, meta-analyses, case series, and case reports of high relevance are selected and reviewed.

RESULTS

Biologics have been used as investigational therapies for EoE in clinical studies over the years, based on earlier work that identified key cytokines and mediators of eosinophilic inflammation and, more recently, type 2 inflammation that underlie EoE pathogenesis. Dupilumab, a monoclonal antibody that targets the interleukin (IL)-4Rα chain, thereby interfering with IL-4 and IL-13 binding with the receptor, was recently approved by the Food and Drug Administration for EoE. Dupilumab improved clinical symptoms, endoscopic scores, histologic inflammation, and esophageal distensibility. Several clinical trials that target key cytokines such as IL-5, IL-13, and thymic stromal lymphopoietin in EoE are still ongoing.

CONCLUSION

Topical corticosteroid, proton pump inhibitor therapy, elimination diet, and dilation are widely accepted treatment modalities for EoE. Dupilumab is the first Food and Drug Administration-approved therapy for EoE. Other studies evaluating biologics that target eosinophils, key cytokines, and inflammatory pathways in EoE are ongoing. Treatment algorithms are needed to position EoE therapies as they emerge.

Endoscopic approach to eosinophilic esophagitis: American Society for Gastrointestinal Endoscopy Consensus Conference

Endoscopy plays a critical role in caring for and evaluating the patient with eosinophilic esophagitis (EoE). Endoscopy is essential for diagnosis, assessment of response to therapy, treatment of esophageal strictures, and ongoing monitoring of patients in histologic remission. To date, less-invasive testing for identifying or grading EoE severity has not been established, whereas diagnostic endoscopy as integral to both remains the criterion standard. Therapeutic endoscopy in patients with adverse events of EoE may also be required. In particular, dilation may be essential to treat and attenuate progression of the disease in select patients to minimize further fibrosis and stricture formation. Using a modified Delphi consensus process, a group of 20 expert clinicians and investigators in EoE were assembled to provide guidance for the use of endoscopy in EoE. Through an iterative process, the group achieved consensus on 20 statements yielding comprehensive advice on tissue-sampling standards, gross assessment of disease activity, use and performance of endoscopic dilation, and monitoring of disease, despite an absence of high-quality evidence. Key areas of controversy were identified when discussions yielded an inability to reach agreement on the merit of a statement. We expect that with ongoing research, higher-quality evidence will be obtained to enable creation of a guideline for these issues. We further anticipate that forthcoming expert-generated and agreed-on statements will provide valuable practice advice on the role and use of endoscopy in patients with EoE.

Esophageal Distensibility Defines Fibrostenotic Severity in Pediatric Eosinophilic Esophagitis

BACKGROUND & AIMS

Identification of fibrosis in pediatric eosinophilic esophagitis (EoE) relies on symptom assessment and endoscopy. Symptoms are highly variable, and early fibrotic remodeling may go undetected on endoscopy yet contribute to esophageal dysfunction. We aimed to assess whether esophageal distensibility has utility in defining fibrostenotic severity in a cohort of pediatric patients with EoE with symptoms of esophageal dysfunction.

METHODS

We analyzed a prospectively recruited a cohort of children ages 9 to 21 years undergoing upper endoscopy and Endoscopic Functional Lumen Imaging Probe (EndoFLIP) for suspected or previously diagnosed EoE. Esophageal distensibility was evaluated by the distensibility index (DI) and esophageal diameter at the distensibility plateau. The association of esophageal distensibility to clinical, endoscopic, and histologic parameters of disease severity was assessed. Receiver operating characteristic analysis was performed to determine the utility of distensibility in defining esophageal rigidity in pediatric EoE.

RESULTS

We identified 59 pediatric patients with EoE undergoing endoscopy and EndoFLIP at a single pediatric tertiary referral center. DI (mm²/mmHg) was significantly lower in patients with fibrotic as compared with inflammatory features on endoscopy (median, 3.3; interquartile range, 2.3-4.4) vs median, 5.5; interquartile range, 4.1-6.0; P = .02) and showed no correlation with eosinophil count. DI <4.5 mm²/mmHg predicted grade 2 rings on endoscopy with area under the curve of 0.81 (P = .0004). DI predicted food impaction in both unadjusted and adjusted models (fully adjusted odds ratio, 1.44; 95% confidence interval, 1.02-2.14; P = .0486).

CONCLUSION

Esophageal distensibility determined by EndoFLIP is a measure of fibrostenotic severity that can be used to clinically phenotype pediatric EoE. We propose parameters of DI <4.5 mm²/mmHg for defining esophageal rigidity in pediatric patients with EoE ages 9 years and older.

A Gap in Care Leads to Progression of Fibrosis in Eosinophilic Esophagitis Patients

BACKGROUND & AIMS

There are few data assessing disease progression in eosinophilic esophagitis (EoE) after diagnosis. We aimed to determine outcomes and assess for progression of fibrosis in patients with EoE with a gap in their regular care.

METHODS

In this retrospective cohort study of newly diagnosed patients with EoE, a "gap" in care was defined as ≥2 years without medical contact for EoE. For inclusion, a gap in care and both pre- and post-gap endoscopies were required. Patients with and without a gap were compared. Data were also compared in gap patients before the gap and after EoE care resumed, and progression of fibrosis and predictors were assessed.

RESULTS

Of 701 patients with EoE, 95 (14%) had a gap in care (mean time without care, 4.8 ± 2.3 years). Post-gap, 12% presented with food impaction requiring emergency evaluation. Compared with pre-gap, patients post-gap had higher endoscopic severity (2.4 vs 1.5; P < .001) and smaller esophageal diameters (11.0 vs 12.7 mm; P = .04). Strictures were more prevalent with longer gap time (P < .05 for trend). Each additional year of gap time increased odds of stricture by 26%, even after accounting for pre-gap dilation. Additionally, of 67 patients without pre-gap fibrosis, 25 (37%) had at least one fibrotic feature (stricture, narrowing, or requiring dilation) post-gap.

CONCLUSIONS

A gap in care of ≥2 years in patients with EoE was associated with signs of increased disease activity, and progression to fibrostenosis was noted, particularly with longer gaps in care. Because EoE can progress to fibrosis even after diagnosis, regular care in patients with EoE is required, perhaps at intervals <2 years.

Functional Luminal Imaging Probe in the Management of Pediatric Esophageal Disorders

BACKGROUND

Functional luminal imaging probe (FLIP) measures pressure-geometry relationships of digestive luminal space. When used in esophageal disorders, it provides several luminal parameters that help better understand the pathophysiology. Data about the potential utility of FLIP in pediatrics are scarce and there is no standardized use in children. We aim to describe the use of FLIP in our center, its safety, feasibility, and clinical impact in esophageal disorders in children.

METHODS

Consecutive FLIP recordings performed at the Centre Hospitalier Universitaire-Sainte-Justine, Montréal, Canada between February 2018 and January 2021 were extracted. A chart review was conducted for demographics and medical history. Symptomatology after the procedure was evaluated with validated dysphagia scores.

KEY RESULTS

Nineteen patients were included (11 girls, median age 16 years, range 3.2-19.6) with achalasia (n = 5), post-Heller's myotomy dysphagia (n = 3), esophagogastric junction outflow obstruction (n = 3), congenital esophageal stenosis (n = 2); post-esophageal atresia repair stricture (n = 3), and post-fundoplication dysphagia (n = 3). There was no significant correlation between integrated relaxation pressure measured with high resolution manometry and distensibility index (DI). The use of FLIP made it possible to differentiate between dysphagia related to an esophageal obstruction (DI < 2.8 mm2/mmHg) and dysphagia without major motility disorder (DI > 2.8 mm2/mmHg) that guided the indication for dilation. FLIP led to a change in management in 47% of the patients. Forty-seven percent of the patients were symptom free at the time of the evaluation.

CONCLUSIONS INFERENCES

FLIP provides key esophageal luminal values and therefore can play an important role in pediatric esophageal disorders management.

Endoscopic Management for Post-Surgical Complications after Resection of Esophageal Cancer

Simple Summary

Flexible endoscopy has an important part in the diagnosis and treatment of postoperative complications after oncologically intended esophagectomy. Endoscopy offers the possibility of effective therapy with minimal invasiveness at the same time, and the use of endoscopic therapy procedures can avoid re-operations. In this review we present the advantages of endoscopic treatment opportunities during the last 20 years regarding patients’ treatment after esophageal cancer resection. According to prevalence and clinical relevance, four relevant postoperative complications were identified and their endoscopic treatment procedures discussed. All endoscopic therapy procedures for anastomotic bleeding, anastomotic insufficiencies, anastomotic stenosis and postoperative delayed gastric emptying are presented, including innovative developments.

Abstract

Background: Esophageal cancer (EC) is the sixth-leading cause of cancer-related deaths in the world. Esophagectomy is the most effective treatment for patients without invasion of adjacent organs or distant metastasis. Complications and relevant problems may occur in the early post-operative course or in a delayed fashion. Here, innovative endoscopic techniques for the treatment of postsurgical problems were developed during the past 20 years. Methods: Endoscopic treatment strategies for the following postoperative complications are presented: anastomotic bleeding, anastomotic insufficiency, delayed gastric passage and anastomotic stenosis. Based on a literature review covering the last two decades, therapeutic procedures are presented and analyzed. Results: Addressing the four complications mentioned, clipping, stenting, injection therapy, dilatation, and negative pressure therapy are successfully utilized as endoscopic treatment techniques today. Conclusion: Endoscopic treatment plays a major role in both early-postoperative and long-term aftercare. During the past 20 years, essential therapeutic measures have been established. A continuous development of these techniques in the field of endoscopy can be expected.

Evidence-based treatments for eosinophilic esophagitis: insights for the clinician

Eosinophilic esophagitis (EoE) is a chronic inflammatory disorder characterized by symptoms of esophageal dysfunction and eosinophil-predominant inflammation. Left untreated, EoE progresses to fibrous remodeling and stricture formation that impairs quality of life. Therefore, EoE requires either repeated treatments or maintenance therapy. Current guidelines recommend swallowed topical corticosteroids (STCs), proton-pump inhibitors (PPIs), or dietary intervention as initial options to induce and maintain long-term disease remission. Impractical exclusive elemental diets and suboptimal allergy testing-directed food avoidance paved the way for empirical elimination diets. These are moderately effective and highly reproducible in inducing EoE remission and allow for identification of specific food triggers. Step-up strategies, including two- and four-food rather than six-food elimination diets, should be considered as initial approaches for dietary treatment in patients of all ages, as they reduce the need for endoscopic procedures, shorten diagnostic processing time, and avoid unnecessary restrictions. Formulations of STC originally designed for asthma therapy are suboptimal for EoE treatment, with new effervescent orodispersible tablets and viscose formulations designed to coat the esophageal mucosa providing increased effectiveness at reduced doses. The anti-inflammatory effects of PPI in EoE are independent from gastric acid secretion inhibition; despite evidence from observational research, PPIs are the most commonly prescribed first-line therapy for EoE due to their accessibility, low cost, and safety profile. Double doses of PPI only induce remission in half of EoE patients, irrespective of the drug used or patients' age. Inflammatory rather than stricturing EoE phenotype and treatment duration up to 12 weeks increase chances of achieving EoE remission. Most responders effectively maintain long-term remission with standard PPI doses. Finally, endoscopic dilation should be considered in patients with reduced esophageal caliber or persistent dysphagia despite histological remission. This article provides a state-of-the-art review and updated discussion of current therapies and newly developed options for EoE.

Plasminogen Activator Inhibitor-1 as a Marker of Esophageal Functional Changes in Pediatric Eosinophilic Esophagitis

BACKGROUND & AIMS

Esophageal remodeling in eosinophilic esophagitis (EoE) can lead to esophageal rigidity with eventual luminal compromise and stenoses. Gauging esophageal functional alterations in EoE is challenging. An epithelial marker of functional remodeling would impact EoE management.

METHODS

Esophageal biopsy specimens from children with and without EoE and primary human esophageal epithelial cells were used for PAI-1 immunohistochemistry, and cell proliferation experiments. PAI-1 immunostaining and basal cell hyperplasia were assessed in the context of concurrently obtained esophageal compliance measures on endoscopic functional lumen imaging probe (EndoFLIP).

RESULTS

EndoFLIPs were performed in 45 children (32 with and 13 without EoE). Epithelial PAI-1 was increased in patients with active EoE versus inactive or control patients (P < .01). Esophageal compliance was lower in EoE patients versus controls, particularly in the proximal esophagus (P < .001). Proximal compliance was the strongest predictor of EoE (AUROC 0.88, 95% CI 0.77, 0.98) with esophageal compliance of less than 2.6%mL/mmHg demonstrating 82% sensitivity and 84% specificity for EoE. PAI-1 inhibition significantly diminished esophageal epithelial cell proliferation, suggesting PAI-1 could trigger basal cell hyperplasia. A composite mid-esophageal BZH + PAI-1 score was the strongest predictor of altered compliance (P = .02, AUROC 0.89 (95% CI 0.80, 0.99).

CONCLUSIONS

PAI-1 is significantly elevated in pediatric EoE and distinguishes altered compliance in children. PAI-1 may be a novel disease marker and therapeutic target.

Pathophysiology of Dysphagia in Eosinophilic Esophagitis: Causes, Consequences, and Management

Eosinophilic esophagitis (EoE) is a leading cause of food bolus impaction in children and adults. The mechanism of dysphagia in EoE, particularly non-obstructive dysphagia, remains incompletely understood. While fibrostenotic processes appear to be critical in the development of dysphagia, somatosensory dysfunction and dysmotility also contribute. This review considers potential mechanisms of dysphagia and evaluates the utility of current and future treatment strategies in this context.

Dysphagia: Novel and Emerging Diagnostic Modalities

Among recent advances in diagnostics for dysphagia and esophageal motility disorders is the update to the Chicago Classification (version 4.0) for interpretation of high-resolution manometry (HRM) and diagnosis of esophageal motility disorders. The update incorporates application of complementary testing strategies during HRM, such as provocative HRM maneuvers, and recommendation for barium esophagram or functional luminal imaging probe (FLIP) panometry to help clarify inconclusive HRM findings. FLIP panometry also represents an emerging technology for evaluation of esophageal distensibility and motility at the time of endoscopy.

Eosinophilic Esophagitis: Incidence, Diagnosis, Management, and Future Directions

Eosinophilic esophagitis (EoE) is an antigen-mediated esophageal disease defined by the presence of esophageal eosinophilia and symptoms of esophageal dysfunction. The pathophysiology involves an allergen-driven Th2 T cell response that triggers infiltration of eosinophils into the esophagus leading to inflammation, remodeling, and fibrosis. This results in disruption of esophageal function and accompanying symptoms - most notably dysphagia. Effective therapies target inflammation or fibrostenotic complications and include proton pump inhibitors, swallowed topical steroids, dietary exclusion, and dilation. Clinical trials testing promising biologic therapies are ongoing.

Pediatric eosinophilic esophagitis: a review for the clinician

Eosinophilic esophagitis (EoE) is a chronic clinical-pathologic disease characterized by eosinophilic infiltration of the esophageal epithelium with esophageal dysfunction symptoms.EoE can occur at any age and has different clinical manifestations depending on the age onset.To date, esophago-gastroduodenal endoscopy (EGD) with biopsy is the gold-standard for EoE diagnosis.According to the recent consensus guidelines, proton pump inhibitors, corticosteroids and elimination diets could be a first-line therapy option. The aim of the treatment is clinical and histological remission for preventing long-lasting untreatable fibrosis.A multidisciplinary approach (allergist, gastroenterology, dietitian, and pathologist) is recommended for managing patients affected by EoE, given the complexity of its treatment.This review will provide a practical guide to assist pediatricians treating children with EoE.Moreover, it highlights the unmet needs in diagnosis and treatment that require urgent attention from the scientific community in the aim of improving the management of patients with EoE.

Proton pump inhibitor therapy reverses endoscopic features of fibrosis in eosinophilic esophagitis

BACKGROUND

Long-standing inflammation leads to esophageal remodeling with stricture formation in patients with eosinophilic esophagitis (EoE). The ability of proton pump inhibitors (PPI) to reverse endoscopic features of fibrosis is still unknown.

OBJECTIVE

To investigate the effect of a short course of PPI treatment in reducing endoscopic findings indicative of esophageal fibrosis in EoE patients.

METHODS

Cross-sectional analysis of the EoE CONNECT registry. Patients who received PPI to induce EoE remission were evaluated. Endoscopic features were graded using the EoE Endoscopic Reference Score (EREFS), with rings and strictures indicating fibrosis. Results were compared to those from patients treated with swallowed topic corticosteroids (STC).

RESULTS

Clinico-histological remission was achieved in 83/166 adult patients treated with PPI (50%) and in 65/79 (82%) treated with STC; among responders, 60 (36%) and 57 (72%) patients respectively achieved deep histological remission (<5 eosinophils/hpf). At baseline, mean±SD EREFS was lower in patients treated with PPI compared to those who received STC (p < 0.001). Short term treatment significantly reduced EREFS scores in patients treated either with PPI or STC as well as rings and strictures. Among patients treated with PPI, deep histological remission (<5 eosinophils/hpf) provided further reduction in total EREFS score.

CONCLUSION

Effective PPI therapy for EoE significantly reduced endoscopic esophageal fibrosis in the short term.

Follow-up and symptom persistence after esophageal food impaction

Esophageal food impactions (EFI) are associated with esophageal pathology, most commonly eosinophilic esophagitis (EoE). Obtaining biopsies provides opportunity for diagnosis, which is important since treatment of EoE decreases the risk for future EFI. Outpatient follow-up rates remain suboptimal and outcomes of patients without timely follow-up are unknown. We aimed to identify the factors associated with pediatric subspecialty follow-up post-EFI and to determine the symptom burden in patients without follow-up. We performed a retrospective review of patients presenting with EFI at a tertiary children's hospital between 2010 and 2018. Patients without subspecialty follow-up within 1 year of EFI were included in a prospective telephone survey investigating the barriers to care, outcomes, and symptoms. Clinical characteristics were compared between groups. Multivariate analysis was used to control for multiple variables. There were 127 EFI identified in 123 individuals (73% male, mean age: 12.2 years). Esophageal biopsies were collected in 76% of cases, and 49% of patients had follow-up. Individuals with follow-up were more likely (P ≤ 0.05) to have had biopsies. In a multivariate analysis, written recommendation for follow-up (Odds Ratio: 6.9 [2.4-19.5], P = 0.001) as well as atopic history and identified stricture were associated with a higher likelihood of follow-up. Those without follow-up had subsequent stricture (35%), dilation (44%), or EFI (39%), and 55% (12/22) described ongoing esophageal symptoms. Identification of treatable findings at time of EFI and ongoing symptom burden after EFI support an imperative for follow-up after EFI. Clear recommendations are a modifiable factor that may improve follow-up in this population.

A unique esophageal extracellular matrix proteome alters normal fibroblast function in severe eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is a chronic TH2 disorder complicated by tissue fibrosis and loss of esophageal luminal patency. The fibrostenotic esophagus does not respond well to therapy, but profibrotic therapeutic targets are largely unclear.

OBJECTIVE

Our aim was to utilize proteomics and primary cells as a novel approach to determine relevant profibrotic factors.

METHODS

We utilized primary esophageal EoE and normal fibroblasts, their derivative extracellular matrixes (ECMs), an approach of fibroblast culture on autologous versus nonautologous ECM, and proteomics to elucidate EoE ECM proteins that dysregulate cellular function.

RESULTS

We cultured esophageal fibroblasts from normal esophagi and esophagi from patients with severe EoE on autologous versus nonautologous ECM. The EoE ECM proteome shifted normal esophageal fibroblast protein expression. Proteomic analysis demonstrated that thrombospondin-1 is detected only in the EoE ECM, is central in the EoE ECM protein-protein interactome, is found at significantly elevated levels in biopsy specimens from patients with active EoE, and induces fibroblast collagen I production.

CONCLUSION

Fibroblasts from patients with EoE secrete a unique ECM proteome that reflects their in vivo state and induces collagen I and α-smooth muscle actin protein expression from normal fibroblasts. Thrombospondin-1 is a previously unappreciated profibrotic molecule in EoE.

Antifibrotic Effects of the Thiazolidinediones in Eosinophilic Esophagitis Pathologic Remodeling: A Preclinical Evaluation

Eosinophilic esophagitis (EoE) is a T-helper 2 (Th2), eosinophilic disease associated with pathologic tissue remodeling that leads to end-organ dysfunction. During early-stage disease, inflammation and subepithelial fibrosis are coupled and reversible, but in late-stage or therapy-resistant disease, there can be uncoupling of these features with progressive esophageal rigidity and strictures contributing to clinical dysphagia and food impactions. No current pharmacotherapeutic interventions directly target esophageal fibrosis. Based on the ability of the thiazolidinediones (TZD) to regulate intestinal and hepatic fibrosis, we tested the antifibrotic effects of the TZDs, rosiglitazone and pioglitazone, in preclinical studies using primary human esophageal fibroblasts.

Solid Swallow Examination During High Resolution Manometry and EGJ-Distensibility Help Identify Esophageal Outflow Obstruction in Non-obstructive Dysphagia

Single water swallow (SWS) high-resolution manometry (HRM) may miss relevant esophageal motility disorders. Solid test meal (STM) during HRM and lately the functional lumen imaging probe (FLIP) have been shown to be of diagnostic value in the assessment of motility disorders. We aimed to assess the diagnostic yield of STM and FLIP in non-obstructive dysphagia (NOD). Patients assessed for dysphagia with both HRM and FLIP between April 2016 and August 2019 were analyzed for signs of non-obstructive EGJ outflow obstruction (EGJOO) according to Chicago Classification 3.0 (CCv3) and CC adapted for the use with solid swallows (CC-S), followed by an individual group-specific analysis. Five subjects without dysphagia served as control group. Standard HRM- and FLIP-values as well as esophagograms and Eckardt Scores were analyzed. Forty-two patients were identified (male/female, 14/36, median age 62). Twenty-five (59.5%) were diagnosed with EGJOO during STM only (= SWS-negative patients; CC-S). The EGJ distensibility index (EGJ-DI) of symptomatic patients was significantly lower compared to the control group (p = 0.006). EGJ-DI was < 3mm²/mmHg in 67% and 88% of patients diagnosed according to CC-S and CCv3, respectively. The IRP during STM showed a significant association to the corresponding EGJ-DI values (p < 0.001). Seventy-six percent of patients received treatment because of additional STM evaluation with a favorable clinical response rate of 89%. STM and FLIP identify EGJOO in symptomatic patients with normal SWS during HRM. STM resembles an inexpensive and clinically meaningful option to diagnose motility disorders and helps to select patients for interventional treatment.

Effect of Maintenance Therapy for Eosinophilic Esophagitis on Need for Recurrent Dilation

BACKGROUND

Eosinophilic esophagitis is an inflammatory condition in which eosinophil infiltration leads to esophageal remodeling and stricturing, with dilation therapy often needed. Achieving histologic remission reduces the need for repeat dilation, although little is known about the effects of long-term maintenance therapy.

AIMS

To further assess the relationship between short-term histologic remission and maintenance therapy on need for repeat dilation in eosinophilic esophagitis.

METHODS

A total of 77 patients with eosinophilic esophagitis (59.7% male; mean age 41.6 years) seen at a single medical center from June 2000 to August 2017 were included. Information on history of dilation and therapy [proton pump inhibitors (PPIs), steroids, elimination diet] was collected. Mean follow-up was 164 weeks. Fifty-one patients achieved histologic remission and 42 of these remained on maintenance therapy (23 PPIs, 14 topical steroids, and 5 dietary therapy). Standard phone interview was completed in cases with lack of follow-up. Only patients who underwent esophageal dilation to ≥ 17 mm were included.

RESULTS

A significantly lower proportion of patients on maintenance therapy required repeat dilation (12/42) compared with patients not on maintenance therapy (8/9) (hazard ratio 0.12; p < 0.001). Of patients who received maintenance therapy, 9.1% required re-dilation. The difference in need for repeat dilation in patients who achieved histologic remission on therapy (14/26) versus those who did not (20/51) was not significant (hazard ratio 1.34; p = 0.45).

CONCLUSION

In a retrospective analysis of patients with eosinophilic esophagitis, we found that a significantly lower proportion who received maintenance therapy (PPIs, steroids, or dietary exclusions) required repeat dilation.

Endoscopy in Pediatric Eosinophilic Esophagitis

Endoscopy and mucosal biopsies are essential to the diagnosis of EoE. Together they either confirm or exclude mucosal eosinophilia and provide a visual inspection of the esophagus that may be consistent with EoE or suggest other underlying etiologies. Endoscopy also plays an important therapeutic role in the management of EoE including the assessment of treatment response and treatment of associated complications including esophageal stricture and food impaction. Assessment of treatment response largely depends on endoscopy and mucosal biopsies although less invasive strategies may eventually provide alternative means to assess mucosal inflammation. Herein we will review current use of endoscopy in EoE, including recently developed technologies and their role in the management of EoE.

Use of the Functional Lumen Imaging Probe in Clinical Esophagology

The functional lumen imaging probe (FLIP) measures luminal dimensions using impedance planimetry, performed most often during sedated upper endoscopy. Mechanical properties of the esophageal wall and opening dynamics of the esophagogastric junction (EGJ) can be objectively evaluated in esophageal motor disorders, eosinophilic esophagitis, esophageal strictures, during esophageal surgery and in postsurgical symptomatic states. Distensibility index, the ratio of EGJ cross sectional area to intraballoon pressure, is the most useful FLIP metric. Secondary peristalsis from balloon distension can be displayed topographically as repetitive anterograde or retrograde contractile activity in the esophageal body, similar to high-resolution manometry. Real-time interpretation and postprocessing of FLIP metadata can complement the identification of esophageal outflow obstruction and achalasia, especially when findings are inconclusive from alternate esophageal tests in symptomatic patients. FLIP can complement the diagnosis of achalasia when manometry and barium studies are inconclusive or negative in patients with typical symptoms. FLIP can direct adequacy of disruption of the EGJ in achalasia when used during and immediately after myotomy and pneumatic dilation. Lumen diameter measured using FLIP in eosinophilic esophagitis and in complex strictures can potentially guide management. An abbreviated modification of the Grading of Recommendations Assessment, Development, and Evaluation was used to determine the quality of available evidence and recommendations regarding FLIP utilization. FLIP metrics that are diagnostic or suggestive of an abnormal motor pattern and metrics that define normal esophageal physiology were developed by consensus and are described in this review.

Dietary therapy for eosinophilic esophagitis: chances and limitations in the clinical practice

INTRODUCTION

Eosinophilic esophagitis (EoE) is a non-Immunoglobulin E-mediated food allergy that currently represents the main cause of dysphagia and food impaction in children and young adults. Diet remains the only therapy targeting the cause of the disease. Relevant advances in recent years allow novel approaches to dietary therapy in EoE.

AREAS COVERED

An up-to-date review on dietary therapy for EoE is provided, as a potential first-line anti-inflammatory therapy able to induce and maintain remission in a significant proportion of patients. Unpractical elemental diets and suboptimal food allergy testing-directed food restrictions paved the way for empiric elimination diets, which currently are to be considered as the most effective drug-free treatment for EoE. After largely restrictive empiric six-food elimination diets, most efficient step-up approaches now include four-food and two-food elimination diets. The potential of milk-elimination is also discussed.

EXPERT COMMENTARY

An empiric elimination diet step-up strategy should be currently considered as the initial approach for dietary treatment in EoE patients of all ages. Compared to a top-down strategy, step-up diets reduce the need for endoscopic procedures, shorten diagnostic process times, and avoid unnecessary restrictions. Furthermore, early identification of responders with few food triggers may select best candidates for maintenance dietary therapy.

Efficacy of proton pump inhibitor therapy for eosinophilic oesophagitis in 630 patients: results from the EoE connect registry

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.

The use of impedance planimetry (Endoscopic Functional Lumen Imaging Probe, EndoFLIP® ) in the gastrointestinal tract: A systematic review

BACKGROUND AND PURPOSE

The EndoFLIP® system is a method of delineating impedance and was first designed to investigate the characteristics of the esophago-gastric junction. In the last decade, its use was widened to investigate other sphincteric and non-sphincteric systems of the gastrointestinal tract. The objective of the present systematic review was to summarize the available data in literature on the use of the EndoFLIP® system in the gastrointestinal tract, including sphincteric and non-sphincteric regions. We performed a systematic review in accordance with recommendations for systematic review using PRISMA guidelines without date restriction, until June 2020, using MEDLINE-PubMed, Cochrane Library, and Google Scholar databases. Only articles written in English were included in the present review. Five hundred and six unique citations were identified from all database combined. Of those, 95 met the inclusion criteria. There was a lack of standardization among studies in terms of anesthetic drugs use, probe placement, and inflation protocol. In most cases, only small cohorts of patients were included. Most studies investigated the EGJ, with a potential use of the EndoFLIP® to identify a subgroup of patients with achalasia and for intraoperative assessment of treatment efficacy in achalasia. However, the use of EndoFLIP® in the esophageal body (esophageal panometry), other esophageal diseases (gastro-esophageal reflux disease, eosinophilic esophagitis), and other sphincter regions (anal canal, pylorus) will need further confirmatory studies. The EndoFLIP® system provides detailed geometric data of the gastrointestinal lumen but further works are needed to determine its use in clinical practice.

Esophageal Functional Lumen Imaging Probe (FLIP): How Can FLIP Enhance Your Clinical Practice?

Recent innovations in esophageal diagnostic testing have enhanced gastroenterology clinical practice by facilitating more nuanced and advanced evaluation of esophageal symptoms. Among these pivotal advances is the FDA-approved functional lumen imaging probe (FLIP), which utilizes impedance planimetry via volumetric distension of a catheter-mounted balloon at the time of sedated upper endoscopy, to acquire esophageal dimensions and pressures. In real time, FLIP can display cross-sectional areas (CSA) and distensibility indices (ratios of CSA to intra-balloon pressures) throughout the esophagus, most notably at the esophagogastric junction, as well as secondary peristaltic esophageal body contractile patterns. As the use of FLIP has progressively spread and permeated into the practice of clinical gastroenterology since its introduction, increasing data on and experiences with its applications have accumulated to guide its utility in clinical practice. In this current review developed for gastroenterologists and foregut surgeons across clinical practice, we provide an introduction to FLIP technology and metrics and discuss the clinical scenarios in which performance of or referral for FLIP may be helpful in the evaluation and management of patients with commonly encountered esophageal symptoms and disorders. Specifically, we discuss the potential applications and limitations of FLIP as a complementary diagnostic modality in patients with non-obstructive dysphagia, established or suspected achalasia spectrum disorders, eosinophilic esophagitis, gastroesophageal reflux disease and those undergoing esophageal surgery.

The functional lumen imaging probe in gastrointestinal disorders: the past, present, and future

The functional lumen imaging probe (FLIP) is a diagnostic tool that utilizes impedance planimetry to allow the assessment of luminal diameter and distensibility. It has been used primarily in esophageal diseases, in particular, in the assessment of achalasia, esophagogastric junction outflow obstruction, and eosinophilic esophagitis (EoE). The usage and publications have increased over the past decade and it is now an essential tool in the armamentarium of the esophagologist. Indications are emerging outside of the esophagus, in particular with regard to gastroparesis. Our paper will review the history of FLIP, optimal current usage, data for key esophageal disorders (including achalasia, reflux, and EoE), data for nonesophageal disorders, and our sense as to whether FLIP is ready for prime time, as well as gaps in evidence and suggestions for future research.

Eosinophilic esophagitis: updates on key unanswered questions

Eosinophilic esophagitis (EoE) is a clinicopathologic disease characterized by symptoms of esophageal dysfunction and esophageal eosinophilia. In the last decade, there has been a dramatic increase in its prevalence for reasons that are not completely understood. The underlying pathophysiology involves an antigen-mediated T_H 2 immune response that draws eosinophils to the esophagus, causing mucosal inflammation, esophageal remodeling, and fibrosis. This ultimately leads to esophageal dysfunction that most commonly manifests as dysphagia. In this review, we will discuss updates on key questions regarding the diagnosis and treatment of EoE.

Clinical outcomes of adults with eosinophilic esophagitis with severe stricture

BACKGROUND AND AIMS

Eosinophilic esophagitis (EoE) is an inflammatory disease of the esophagus. Its prevalence has been increasing steadily over the past 3 decades. The prognosis of patients with EoE presenting with severe esophageal strictures is poorly understood. The aim of this study was to describe the clinical outcomes of patients with EoE with severe strictures and identify factors associated with a greater likelihood of improvement in esophageal diameter.

METHODS

This study is a retrospective chart review of patients with EoE with severe stricture, defined as an esophageal diameter of 10 mm or less at one point in their disease course. Each patient's clinical course was followed during standard-of-care follow-up with medical or dietary therapy in conjunction with repeated esophageal dilation. Multivariate regression analysis was performed to determine which variables are associated with endoscopic response, defined by an improvement in esophageal diameter to 13 mm and to 15 mm.

RESULTS

From a cohort of 1091 adults with EoE, severe strictures were identified in 66 patients (7%). Of the 66 patients, 59 (89%) achieved an esophageal diameter of ≥13 mm and 43 (65%) achieved ≥15 mm. Initial diameter (odds ratio, 1.58; 95% confidence interval, 1.06-2.35; P = .025) and histologic remission (odds ratio, 34.97; 95% confidence interval, 6.45-189.49; P < .0001) were significantly associated with achieving a diameter ≥15 mm. Age at diagnosis, gender, and number of months to maximum esophageal diameter were not associated with achieving either diameter.

CONCLUSIONS

Most patients with EoE with severe stricture experienced improvement in esophageal diameter to ≥15 mm with treatment, suggesting that the currently available treatment options are effective for patients with severe strictures. The most significant factors associated with disease reversibility are initial esophageal diameter and histologic remission.

EsoFLIP for esophageal dilation: proposed advantages

PURPOSE OF REVIEW

The EsoFLIP integrates impedance planimetry technology into a dilator balloon capable of dilating from diameters between 10 and 30 mm via controlled volumetric distension while providing real-time visualization and objective measurement during the dilation procedure, potentially negating the need for fluoroscopy. This review aims to describe the use and application of EsoFLIP and the potential advantages this novel technology may afford.

RECENT FINDINGS

Small pilot and retrospective studies demonstrate EsoFLIP feasibility and safety, but larger studies are needed to understand its impact on clinical outcomes.

SUMMARY

EsoFLIP is an appealing new technology that offers advantages in therapeutic dilation of the lower esophageal sphincter in achalasia or of esophageal strictures because of previous surgery, gastroesophageal reflux disease, or radiation.