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Updated: May 13, 2026
09:34
A Combinatorial Single-cell Approach to Characterize the Molecular and Immunophenotypic Heterogeneity of Human Stem and Progenitor Populations
Published on: October 25, 2018
NERD: an umbrella term including heterogeneous subpopulations
Edoardo Savarino1, Patrizia Zentilin, Vincenzo Savarino
1Division of Gastroenterology, Department of Surgical, Oncological and Gastroenterological Sciences, University of Padua, Via Giustiniani 2, 35128 Padua, Italy.
Nature Reviews. Gastroenterology & Hepatology
|March 27, 2013
Summary
Nonerosive reflux disease (NERD) patients require precise classification using 24-hour impedance-pH testing to differentiate between acid reflux, hypersensitive esophagus, and functional heartburn. This distinction guides targeted therapies for improved patient outcomes.
Area of Science:
- Gastroenterology
- Digestive Health
- Esophageal Disorders
Background:
- Nonerosive reflux disease (NERD) is the most common presentation of GERD, characterized by typical symptoms without visible endoscopic mucosal breaks.
- Patients with NERD exhibit significant pathophysiological heterogeneity, necessitating advanced diagnostic approaches.
Purpose of the Study:
- To highlight the importance of 24-hour impedance-pH testing for accurate classification of NERD patients.
- To differentiate between subtypes of NERD and functional heartburn for appropriate management.
Main Methods:
- Utilizing 24-hour impedance-pH testing to detect acidic and weakly acidic reflux.
- Correlating reflux events with patient symptoms to identify underlying mechanisms.
- Distinguishing NERD subtypes and functional heartburn based on impedance-pH findings.
Main Results:
- Impedance-pH testing identifies two NERD subsets: those with excess acid and those with hypersensitive esophagus to various reflux types.
- Functional heartburn patients are identified as not having underlying reflux and should be excluded from GERD diagnoses.
- Microscopic esophagitis and intercellular space dilation may play a role in NERD symptom generation.
Conclusions:
- Accurate classification of NERD via impedance-pH testing is crucial for effective treatment.
- NERD patients with acid as the primary factor respond to PPIs; those with hypersensitive esophagus may benefit from reflux inhibitors or surgery.
- Functional heartburn requires management with pain modulators, pending further clinical trials.
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