Nasal pepsin assay and pH monitoring in chronic rhinosinusitis

OBJECTIVES/HYPOTHESIS: The primary objective of this study was to determine the relationship between chronic rhinosinusitis (CRS) and laryngopharyngeal reflux (LPR). We also investigated the diagnostic value of pepsin in nasal lavage by means of fluorometric assay as compared with 24-hour dual-probe pH monitoring. STUDY DESIGN AND METHODS: This is a controlled, prospective study from a retrospective dataset of 33 patients recruited for endoscopic sinus surgery between 2005 and 2006 in a tertiary care referral center (Hacettepe University Medical Center). All patients underwent 24-hour dual-probe pH monitoring and nasal lavage fluid investigation for pepsin. A fluorometric pepsin assay using casein-fluorescein isothiocyanate in nasal lavage fluid was used to detect LPR. The control group included 20 patients who were proven not to have sinusitis. RESULTS: A higher incidence of pharyngeal acid reflux events was found in patients with CRS (29 of 33, 88%) compared with the control patients (11 of 20, 55%). The difference was statistically significant (P = .01). The fluorometric pepsin assay was correlated to the results of 24-hour dual-probe monitoring for LPR diagnosis with a 100% sensitivity and 92.5% specificity. These data suggest that an association between CRS and LPR is present and that the detection of pepsin in nasal lavage fluid may provide a noninvasive and feasible method of LPR screening.