Clinical relevance of salivary pepsin detection in diagnosing gastroesophageal reflux disease subtypes

Mengyu Zhang; Tingting Wu; Niandi Tan; Songfeng Chen; Qianjun Zhuang; Yu Luo; Yinglian Xiao

doi:10.1093/gastro/goad053

摘要：Background:Gastroesophageal reflux disease(GERD)is heterogeneous with a varied symptom spectrum and reflux profiles.Its defi-nite diagnosis often requires invasive tools including endoscopy or reflux monitoring.The aim of this study was to investigate the clinical relevance of salivary pepsin detection as a non-invasive screening tool to diagnose GERD of different subtypes. Methods:A total of 77 patients with suspected GERD symptoms and 12 asymptomatic controls were analysed.All participants per-formed symptom evaluation,upper endoscopy,esophageal manometry,and 24-hour multichannel intraluminal impedance-dual pH probe monitoring.Saliva was self-collected across three different time points:at early fasting,postprandially,and at symptom occur-rence.Salivary pepsin levels were measured via Peptest.The optimal threshold of salivary pepsin for diagnosing distal or proximal reflux was determined according to a receiver-operating characteristic curve. Results:The average salivary pepsin concentration of suspected GERD patients was significantly higher than that of controls(100.63[68.46,141.38]vs 67.90[31.60,115.06]ng/mL,P=0.044),although no difference was found among patients with different symptom spectrums.The distal reflux group had a higher average pepsin concentration than non-reflux patients(170.54[106.31,262.76]vs 91.13[63.35,127.63]ng/mL,P=0.043),while no difference was observed between the distal reflux group and the proximal reflux group.The optimal cut-off value of salivary pepsin concentration for diagnosing pathological distal reflux was 157.10 ng/mL,which was higher than that for diagnosing pathological proximal reflux(122.65 ng/mL).The salivary pepsin concentration was significantly correlated with distal and proximal reflux parameters. Conclusions:Salivary pepsin measurement can help in identifying true GERD with pathological distal reflux or proximal reflux,re-gardless of different symptom spectrums.A higher threshold should be applied for diagnosing distal reflux than for proximal reflux.