Effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases: physiopathology and therapeutic targets

PURPOSE: Laryngopharyngeal reflux disease (LPRD) is a general term for the reflux of gastroduodenal contents into the laryngopharynx, oropharynx and even the nasopharynx, causing a series of symptoms and signs. Currently, little is known regarding the physiopathology of LPRD, and proton pump inhibitors (PPIs) are the drugs of choice for treatment. Although acid reflux plays a critical role in LPRD, PPIs fail to relieve symptoms in up to 40% of patients with LPRD. The influence of other reflux substances on LPRD, including pepsin, bile acid, and trypsin, has received increasing attention. Clarification of the substances involved in LPRD is the basis for LPRD treatment. METHODS: A review of the effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases was conducted in PubMed. RESULTS: Different reflux substances have different effects on LPRD, which will cause various symptoms, inflammatory diseases and neoplastic diseases of the laryngopharynx. For LPRD caused by different reflux substances, 24-h multichannel intraluminal impedance combined with pH-metry (MII-pH), salivary pepsin, bile acid and other tests should be established so that different drugs and treatment courses can be used to provide patients with more personalized treatment plans. CONCLUSION: This article summarizes the research progress of different reflux substances on the pathogenesis, detection index and treatment of LPRD and lays a theoretical foundation to develop target drugs and clinical diagnosis and treatment.