Advances in Diagnostic Approaches and Prognostic Stratification of Esophageal Motility Disorders and Gastroesophageal Reflux Disease

Dear Colleagues,

In recent years, remarkable technological advances have transformed the evaluation of gastrointestinal motility and function, offering new opportunities for precision diagnosis, biomarker identification, and prognostic stratification. The International Working Group for Disorders of Gastrointestinal Motility and Function has emphasized that the routine application of these diagnostic modalities can identify clinically significant abnormalities that are fundamental to accurate disease characterization. Against this backdrop, this Special Issue aims to showcase cutting-edge diagnostic strategies, emerging functional biomarkers, and evidence-based prognostic algorithms that enhance the clinical evaluation of patients with esophageal motility disorders and gastroesophageal reflux disease (GERD).

High-resolution manometry (HRM) is currently regarded as the gold-standard technique for assessing esophageal peristalsis and lower esophageal sphincter (LES) function. The introduction of HRM catheters has enabled continuous pressure topography throughout the esophagus, allowing a comprehensive and accurate assessment of both esophageal body motility and sphincter function. The integration of intraluminal impedance into HRM systems has further enhanced diagnostic capability by providing objective evaluation of bolus transit through the esophagus, measured via changes in electrical resistance detected by impedance sensors along the catheter. Beyond qualitative diagnosis, HRM-derived parameters—such as resting LES pressure, integrated relaxation pressure (IRP), and distal contractile integral (DCI)—serve as physiological biomarkers that correlate with symptom patterns and facilitate refined disease subtyping.

A major milestone in HRM evolution has been the development of the Chicago Classification (CC), which now serves as the internationally accepted framework for interpreting HRM studies. The CC categorizes esophageal motility disorders into major disorders—including achalasia, esophagogastric junction outflow obstruction, and absent contractility—and minor disorders, such as ineffective esophageal motility. Major motility disorders are typically associated with distinct pathophysiological profiles and more pronounced symptom burdens, whereas minor abnormalities may also be observed in asymptomatic individuals. Importantly, the CC framework enables diagnostic precision and prognostic risk stratification by clearly distinguishing phenotypes with different clinical trajectories, thereby informing the need for further confirmatory testing and surveillance intensity.

More recently, the endoluminal functional lumen imaging probe (EndoFLIP) has emerged as a valuable adjunctive diagnostic tool in clinical practice. Performed under sedation, EndoFLIP evaluates esophagogastric junction function using a balloon-based system that measures luminal distensibility—a functional biomarker of sphincter compliance. Beyond its established role in esophageal disorders, EndoFLIP has also demonstrated utility in the evaluation of pyloric dysfunction, offering additional diagnostic insights for patients with complex presentations.

Advances in fluoroscopic techniques, including videofluoroscopic swallowing examination (VFSE), timed barium swallow (TBS), and timed barium surface area measurement, have further broadened the diagnostic armamentarium. These techniques provide complementary morphological and functional data that aid in assessing bolus clearance, detecting structural abnormalities, and monitoring disease progression over time.

Gastroesophageal reflux disease (GERD) is a highly prevalent condition that can significantly impair quality of life through persistent and, at times, severe symptoms. In routine clinical practice, GERD is frequently diagnosed on the basis of symptom history and response to acid-suppressive therapy. However, growing evidence indicates that symptom presentation alone correlates poorly with objectively documented pathological reflux. Consequently, only a subset of patients undergo diagnostic endoscopy to evaluate for complications such as erosive esophagitis or Barrett's esophagus. According to the Lyon Consensus, a definitive diagnosis of pathological GERD can be established when acid exposure time (AET) exceeds 6% during 24-hour pH-impedance monitoring. This objective threshold not only serves as a diagnostic biomarker but also carries prognostic value, as elevated AET has been associated with increased risk of disease progression and long-term complications, thereby guiding the selection of patients who merit closer diagnostic surveillance.

Looking ahead, the integration of multi-modal diagnostic data—ranging from HRM metrics and EndoFLIP distensibility indices to pH-impedance parameters and emerging molecular biomarkers—holds great promise for developing robust diagnostic and prognostic models. Such models may enable earlier and more accurate phenotype identification, improved risk prediction, and personalized diagnostic algorithms. This Special Issue invites contributions that advance our understanding of diagnostic accuracy, biomarker discovery, and prognostic stratification in esophageal motility disorders and GERD, ultimately aiming to bridge the gap between innovative diagnostics and enhanced clinical decision-making.

Dr. Amir Mari
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the Special Issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-anonymized peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Diagnostics is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.