We aimed to explore the diagnostic value of salivary pepsin forextra-esophageal manifestations of gastroesophageal reflux disease (GERD).

Studies were performed in fifteen healthy volunteers (groupC)and fifteen patients(group E)confirmed by GerdQ, reflux symptom index(RSI), reflux finding score patients(RFS) and 24-hour multichannel intraluminal impedance pH (24 h MII-pH).Saliva were collected on waking time and 2 hours after lunch and dinner as well as uncomfortableness. Salivary pepsin was analyzed by ELISA. Based on the differences in salivary pepsin, the diagnostic value of it was discussed.

The concentration of salivary pepsin was 63.59±14.34 ng/ml in group C and 128.98±17.28 ng/ml in group E, and the date in group E was significantly higher than that in group C(P=0.000). While comparing the level of salivary pepsin during different timeframes between group C and E, those of group E were always higher than those of group C（p=0.000). To compare the salivary pepsin during different timeframes in group C and E separately, there was no significant difference in group C. But, significant differences were found in group E. The salivary pepsin was 124.28±17.50 ng/ml on waking time, and 143.54±12.60 ng/ml two hours after lunch, and 122.00±15.77 ng/ml two hours after dinner, and 126.10±12.60 ng/ml when uncomfortableness. It was highest when it was collected two hours after lunch. Compared with that on waking time and two hours after dinner as well as uncomfortableness, it was always significantly higher (p=0.003, 0.001, 0.008).

Salivary pepsin has prominent diagnostic value for extra-esophageal manifestations of GERD. The level of salivary pepsin for extra-esophageal manifestations of GERD always increases significantly anytime, but it has the greatest diagnostic significance when the saliva collected two hours after lunch, probably due to the immediate post-lunch nap.