Related Experiment Video
Updated: Aug 16, 2026
Simultaneous Laryngopharyngeal and Conventional Esophageal pH Monitoring
Published on: December 14, 2020
Sensitive pepsin immunoassay for detection of laryngopharyngeal reflux
John Knight1, Mark O Lively, Nikki Johnston
1Center for Voice and Swallowing Disorders, Department of Otolaryngology, Wake Forest University Health Sciences, Winston-Salem, NC 27157, U.S.A.
Objectives/Hypothesis:
To determine whether measurement of pepsin in throat sputum by immunoassay could be used as a sensitive and reliable method for detecting laryngopharyngeal reflux (LPR) compared with 24-hour double-probe (esophageal and pharyngeal) pH monitoring.
Study Design:
Patients with clinical LPR undergoing pH monitoring provided throat sputum samples during the reflux-testing period for pepsin measurement using enzyme-linked immunoadsorbent assay.
Results:
Pepsin assay results from 63 throat sputum samples obtained from 23 study subjects were compared with their pH monitoring data. Twenty-two percent (14/63) of the sputum samples correlated the presence of pepsin with LPR (pH < or = 4 at the pharyngeal probe), of which the median concentration of pepsin was 0.18 microg/mL (range 0.003-22 microg/mL). Seventy-eight percent (49/63) of the samples unassociated with (pharyngeal) reflux contained no detectible pepsin. Mean pH values for pepsin-positive samples were significantly lower than negative samples at both esophageal probe (pH 2.2 vs. pH 5.0) (P < .01) and the pharyngeal probe (pH 4.4 vs. pH 5.8) (P < .01). When the pepsin assay results were compared with the pharyngeal pH data for detecting reflux (events pH < or = 4), the pepsin immunoassay was 100% sensitive and 89% specific for LPR.
Conclusions:
Detection of pepsin in throat sputum by immunoassay appears to provide a sensitive, noninvasive method to detect LPR.
More Related Videos
03:33Rapid Detection of Fecal Antigen of Helicobacter pylori Infection Based on Double Antibody Sandwich Detection Technology
Published on: May 23, 2025
08:25Construction of a Wireless-Enabled Endoscopically Implantable Sensor for pH Monitoring with Zero-Bias Schottky Diode-based Receiver
Published on: August 27, 2021
Related Concept Videos
01:28Peptic Ulcer Disease III: Clinical Manifestations and Diagnostic Studies
Few clinical manifestations differentiate gastric ulcers from duodenal ulcers. Distinctions in the location, timing, and pain relief are crucial for healthcare providers in differentiating between gastric and duodenal ulcers during clinical assessments.
01:29Gastroesophageal Reflux Disease II: Clinical Features and Management
Clinical Manifestations
GERD presents itself in a multitude of ways, with symptoms varying from person to person. The hallmark symptoms are...
01:33Enzyme-Linked Immunosorbent Assay
There are many different types of ELISAs, but they all involve an antibody molecule whose constant region binds an enzyme, leaving the variable region free to bind its specific antigen. Enzyme-substrate reaction allows the antigen to be visualized or quantified.