Measuring esophageal compliance using functional lumen imaging probe to assess remodeling in eosinophilic esophagitis

Enhancing Chicago Classification diagnoses with functional lumen imaging probe-mechanics (FLIP-MECH)

BACKGROUND

Esophageal motility disorders can be diagnosed by either high-resolution manometry (HRM) or the functional lumen imaging probe (FLIP) but there is no systematic approach to synergize the measurements of these modalities or to improve the diagnostic metrics that have been developed to analyze them. This work aimed to devise a formal approach to bridge the gap between diagnoses inferred from HRM and FLIP measurements using deep learning and mechanics.

METHODS

The "mechanical health" of the esophagus was analyzed in 740 subjects including a spectrum of motility disorder patients and normal subjects. The mechanical health was quantified through a set of parameters including wall stiffness, active relaxation, and contraction pattern. These parameters were used by a variational autoencoder to generate a parameter space called virtual disease landscape (VDL). Finally, probabilities were assigned to each point (subject) on the VDL through linear discriminant analysis (LDA), which in turn was used to compare with FLIP and HRM diagnoses.

RESULTS

Subjects clustered into different regions of the VDL with their location relative to each other (and normal) defined by the type and severity of dysfunction. The two major categories that separated best on the VDL were subjects with normal esophagogastric junction (EGJ) opening and those with EGJ obstruction. Both HRM and FLIP diagnoses correlated well within these two groups.

CONCLUSION

Mechanics-based parameters effectively estimated esophageal health using FLIP measurements to position subjects in a 3-D VDL that segregated subjects in good alignment with motility diagnoses gleaned from HRM and FLIP studies.

Optimal Assessment, Treatment, and Monitoring of Adults with Eosinophilic Esophagitis: Strategies to Improve Outcomes

Eosinophilic esophagitis (EoE) is a chronic type 2 inflammation-mediated disease characterized by an eosinophil-predominant inflammation of the esophagus and symptoms of esophageal dysfunction. Relevant treatment outcomes in the setting of EoE include the improvement of histology, symptoms, and endoscopy findings, quality of life (QoL), and the psychological burden of the disease. Established validated tools for the assessment of EoE include questionnaires on dysphagia and QoL (ie, DSQ, EEsAI, and EoE-IQ). More recently, esophageal symptom-specific anxiety and hypervigilance, assessed using the esophageal hypervigilance and anxiety scale (EHAS), have emerged as contributors to disease burden, confirming the importance of psychological aspects in EoE patients. The EoE endoscopic reference score (EREFS) is the only validated endoscopy score in EoE and can quantify mucosal disease burden. However, esophageal panometry using the functional lumen imaging probe (FLIP) and high-resolution manometry (HRM) have shown potential to optimize the assessment of fibrostenotic features of EoE, providing novel insights into the pathophysiology of symptoms. There is a growing number of licenced and off-label therapeutic options in EoE, with various randomized controlled trials demonstrating the efficacy of proton pump inhibitors, topical steroids, food elimination diets, biological drugs, and esophageal dilatation. However, standardized optimal management strategies of EoE are currently lacking. In this review, we provide an overview of established and novel assessment tools in EoE including patient reported outcomes, FLIP panometry, HRM, endoscopy, and histology outcome measures to improve the outcomes of EoE patients. In addition, we summarize available therapeutic options for EoE based on the most recent evidence.

Long-term Outcome of Asymptomatic Esophageal Eosinophilia

Background/Aims

: Asymptomatic esophageal eosinophilia (aEE), characterized by eosinophil infiltration in the esophagus without clinical symptoms, has been reported as a precursor of eosinophilic esophagitis (EoE). Nevertheless, no report exists on the long-term clinical course of the disease. Therefore, this study aimed to investigate the long-term clinical course of aEE over 5 years, including the symptomatic conversion rate and the effect of treatments.

Methods

: We reviewed 28 patients with aEE who had been followed up for over 5 years with endoscopic monitoring. The basal characteristics of patients were compared with those of 58 patients diagnosed with EoE during the same period. Patients' clinicopathological findings were collected and examined.

Results

: No significant differences in basal characteristics and histopathological findings were observed between the patients with aEE and those with EoE. The median follow-up duration was 64 months. Among the 28 patients with aEE, seven were treated with proton pump inhibitor or potassium-competitive acid blocker and the remaining 21 opted for follow-up with no medication. Among the treated patients, six (85.7%) exhibited endoscopic and pathologic improvements. Among the cases followed up without medication, the findings worsened in two (9.5%), improved spontaneously in seven (33.3%), and were unchanged in 12 (57.1%), and three (14.3%) developed symptoms at a mean time of 40 months. Symptoms developed in cases where endoscopic and pathologic findings remained unchanged or worsened during follow-up.

Conclusions

: Some patients with aEE had improved findings without treatment, whereas others developed symptoms, emphasizing the importance of long-term monitoring and individualized treatment decisions.

The 1st EoETALY Consensus on the Diagnosis and Management of Eosinophilic Esophagitis-Current Treatment and Monitoring

The present document constitutes Part 2 of the EoETALY Consensus Statements guideline on the diagnosis and management of eosinophilic esophagitis (EoE) developed by experts in the field of EoE across Italy (i.e., EoETALY Consensus Group). Part 1 was published as a different document, and included three chapters discussing 1) definition, epidemiology, and pathogenesis; 2) clinical presentation and natural history and 3) diagnosis of EoE. The present work provides guidelines on the management of EoE in two final chapters: 4) treatment and 5) monitoring and follow-up, and also includes considerations on knowledge gaps and a proposed research agenda for the coming years. The guideline was developed through a Delphi process, with grading of the strength and quality of the evidence of the recommendations performed according to accepted GRADE criteria.This document has received the endorsement of three Italian national societies including the Italian Society of Gastroenterology (SIGE), the Italian Society of Neurogastroenterology and Motility (SINGEM), and the Italian Society of Allergology, Asthma, and Clinical Immunology (SIAAIC). The guidelines also involved the contribution of members of ESEO Italia, the Italian Association of Families Against EoE.

Esophageal Remodeling Correlates With Eating Behaviors in Pediatric Eosinophilic Esophagitis

INTRODUCTION

There are limited data characterizing eating habits among pediatric patients with eosinophilic esophagitis (EoE). We compared eating behaviors in pediatric patients with EoE with healthy controls and assessed the degree of correlation with symptomatology, endoscopic and histologic findings, and esophageal distensibility.

METHODS

We conducted a prospective, observational study where subjects consumed 4 food textures (puree, soft solid, chewable, and hard solid) and were scored for eating behaviors including number of chews per bite, sips of fluid per food, and consumption time. Symptomatic, endoscopic, histologic, and esophageal distensibility data were collected for case subjects.

RESULTS

Twenty-seven case subjects and 25 healthy controls were enrolled in our study (mean age 11.0 years, 63.5% male). Compared with healthy controls, pediatric patients with EoE demonstrated more chews per bite with soft solid (13.6 vs 9.1, P = 0.031), chewable (14.7 vs 10.7, P = 0.047), and hard solid foods (19.0 vs 12.8, P = 0.037). Patients with EoE also demonstrated increased consumption time with soft solid (94.7 vs 58.3 seconds, P = 0.002), chewable (90.0 vs 65.1 seconds, P = 0.005), and hard solid foods (114.1 vs 76.4 seconds, P = 0.034) when compared with healthy controls. Subgroup analysis based on disease status showed no statistically significant differences in eating behaviors between active and inactive EoE. Total endoscopic reference score positively correlated with consumption time ( r = 0.53, P = 0.008) and number of chews ( r = 0.45, P = 0.027) for chewable foods and with number of chews ( r = 0.44, P = 0.043) for hard solid foods. Increased consumption time correlated with increased eosinophil count ( r = 0.42, P = 0.050) and decreased esophageal distensibility ( r = -0.82, P < 0.0001).

DISCUSSION

Altered eating behaviors including increased chewing and increased consumption time can be seen in pediatric patients with EoE, can persist despite histologic remission, and may be driven by changes in esophageal distensibility.

Mechanotransduction-induced interplay between phospholamban and yes-activated protein induces smooth muscle cell hypertrophy

The gastrointestinal system is a hollow organ affected by fibrostenotic diseases that cause volumetric compromise of the lumen via smooth muscle hypertrophy and fibrosis. Many of the driving mechanisms remain unclear. Yes-associated protein-1 (YAP) is a critical mechanosensory transcriptional regulator that mediates cell hypertrophy in response to elevated extracellular rigidity. In the type 2 inflammatory disorder, eosinophilic esophagitis (EoE), phospholamban (PLN) can induce smooth muscle cell hypertrophy. We used EoE as a disease model for understanding a mechanistic pathway in which PLN and YAP interact in response to rigid extracellular substrate to induce smooth muscle cell hypertrophy. PLN-induced YAP nuclear sequestration in a feed-forward loop caused increased cell size in response to a rigid substrate. This mechanism of rigidity sensing may have previously unappreciated clinical implications for PLN-expressing hollow systems such as the esophagus and heart.

Pathophysiology and Clinical Impact of Esophageal Remodeling and Fibrosis in Eosinophilic Esophagitis

Most of the major clinical signs and consequences of eosinophilic esophagitis seem to be related to tissue remodeling. Important data on remodeling activity in patients with eosinophilic esophagitis are provided by a range of current and new biologic markers and diagnostics. To completely clarify the possible advantages and restrictions of therapeutic approaches, clinical studies should take into consideration the existence and reversibility of esophageal remodeling. The degree of mucosal or submucosal disease activity may not be reflected by epithelial eosinophilic inflammation, which is used to define one criterion of disease activity".

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 PhysioMechanical Model of Esophageal Function in Eosinophilic Esophagitis

BACKGROUND & AIMS

Eosinophilic esophagitis (EoE) is characterized by eosinophilic inflammation, but also heterogeneous presentations involving fibrostenotic esophageal remodeling and esophageal dysmotility. We aimed to define and evaluate phenotypes of EoE using functional lumen imaging probe (FLIP) panometry (ie, a PhysioMechanical classification of EoE).

METHODS

Patients with EoE who completed FLIP during endoscopy were included in a cross-sectional study. FLIP studies were analyzed for distensibility plateau and compliance of the esophageal body, maximum esophagogastric junction diameter, and contractile response pattern. These FLIP features were then applied to define PhysioMechanical classifications.

RESULTS

A total of 215 patients with EoE (mean [standard deviation] age 38 [12] years; 31% female) were included. Seven PhysioMechanical classifications were identified that differed by various clinical characteristics, including symptom duration (P < .001) and Endoscopic EoE Reference Scores (EREFS) (P < .001). In particular, patients with "nonreactive fibrostenosis" (n = 14), had greater symptom duration (median [interquartile range] 20 [10-30] years) and more frequently had EREFS grade 2 or 3 ring scores (14 of 14 patients) than patients with a "normal" PhysioMechanical classification (symptom duration: 3 [1-8] years; 4 of 50 [8%] had EREFS grade 2 or 3 rings). In addition, among patients off treatment at cross-sectional evaluation (n = 46), there was a difference between PhysioMechanical classifications in future proton pump inhibitor (PPI) response rates (ie, achieving peak mucosal eosinophil count <15 per high-powered field after PPI treatment); P = .009. PPI response ranged from 87% (13 of 15 patients) with "isolated esophagogastric junction outflow obstruction" to 11% (1 of 9 patients) with "spastic-reactive fibrostenosis."

CONCLUSIONS

Classifying PhysioMechanical esophageal function in EoE based on FLIP panometry features may facilitate defining disease severity and directing management in EoE.