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Sensitive pepsin immunoassay for detection of laryngopharyngeal reflux. Laryngoscope 2005 Aug;115(8):1473-8



Pubmed ID




Scopus ID

2-s2.0-23344449645   89 Citations


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.

Author List

Knight J, Lively MO, Johnston N, Dettmar PW, Koufman JA


Nikki Johnston PhD Associate Professor in the Otolaryngology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Acid-Base Equilibrium
Analysis of Variance
Cohort Studies
Enzyme-Linked Immunosorbent Assay
Gastric Acidity Determination
Gastric Juice
Gastroesophageal Reflux
Hydrogen-Ion Concentration
Middle Aged
Monitoring, Physiologic
Pepsin A
Prospective Studies
Sensitivity and Specificity
Severity of Illness Index
jenkins-FCD Prod-480 9a4deaf152b0b06dd18151814fff2e18f6c05280