The diagnostic value of pepsin concentration in saliva for laryngopharyngeal reflux disease.

Abstract

To explore the diagnostic efficacy of pepsin concentration in saliva for laryngopharyngeal reflux (LPR) disease. In this study, we recruited 40 participants with abnormal sensation of throat into the study who visited our hospital from March 2020 to December 2020. The 24h multichannel intraluminal impedance and pH monitoring (24h MII-pH), reflux symptom index (RSI) and reflux finding score (RFS), pepsin concentration in saliva were collected. The Cohen's kappa test and receiver-operating characteristic (ROC) curves were performed to determine and compare the sensitivity and specificity of five diagnostic methods: RSI; RFS, pepsin concentration, RSI + RFS, RSI + RFS + pepsin concentration. The area under the curve (AUC) of RSI, RFS, pepsin concentration, RSI + RFS, RSI + RFS + pepsin concentration were 0.767, 0.733, 0.870, 0.750,0.867, respectively. That is, the pepsin concentration has maximum AUC (the cutoff point is 219.47 (ng/mL); the sensitivity and 1-specificity is 0.300, 0.933, respectively.). The positive predictive value was 90.3% (28/31), and the negative predictive value was 77.8% (7/9). The Cohen's kappa coefficients of the five diagnostic subgroups were: RSI 0.486 (95% CI 0.207-0.764, P = 0.001); RFS 0.333 (95% CI 0.021-0.644, P = 0.032); RSI + RFS: 0.517 (95% CI 0.205-0.829, P = 0.001); pepsin concentration: 0.699 (95% CI 0.379-0.931, P = 0.001); RSI + RFS + pepsin concentration: 0.500 (95% CI 0.181-0.819, P < 0.001). The pepsin concentration has the maximum AUC area and highest consistency with the 24h MII-pH. Therefore, it has certain value in the screening and diagnosis of diseases related to LPR disease.