The Application Of Pepsin Content Test In Saliva/sputum For Diagnosis Of Laryngopharyngeal Reflux Disease

Background and purpose:The prevalence of laryngopharyngeal reflux(LPR)has been constantly rising year by year in the whole world and affects an alarmingly high percentage of the general population in the east and west.In 2002,the American Academy of Otolaryngology and throat and neck surgery began to introduce the concept of laryngopharyngeal renflux disease,LPRD).It is considered that the disease and gastroesophageal reflux disease were two different diseases,they also named formally the LPRD and recognized it as an independent disease in otorhinolaryngological department.Over the past ten years many researchers in the world have done lots of research on the etiology,pathogenesis and pathological mechanism of reflux disease to prove that the damage of the pharynx and larynx is mainly caused by the pepsin activated by Hydrochloric acid(HCI).In normal cases,pepsin should exist only in the stomach,not existing in the throat.The mucosa epithelium of the esophagus can express carbonic anhydrase isozyme I,II,III and IV Different from the epithelium of the esophagus,the mucosa of the pharynx and the larynx can’t produce enough carbonic anhydrase and has no natural resistance barrier to the pepsin.When the[H+]and pepsinogen In the stomach reflux into the throat,the mucous membrane of the throat is unable to produce enough carbonate to neutralize[H+][1],pepsinogen is activated by[H+]as a pepsin,the latter causes the mucosa membrane of the throat to be damaged and then appearing the corresponding signs and clinical symptoms.With the progress in the study of the pathogenesis of laryngopharyngeal reflux disease,scholars have paid more and more attention to the role of pepsin in the laryngopharyngeal reflux disease.The common puzzling phenomenon of gastric acid and pepsin,which does not damage the esophagus but can damage the pharynx and larynx airway,is gradually recognized.The effect of diagnosis in laryngopharyngeal reflux disease has been confirmed in all experiments.Accordingly,if we can detect pepsin in the throat of patients,we can prove the existence of reflux events.However,due to the lag of detection methods,the clinicians still adopt some nonspecific scoring methods、clinical experience and experimental therapeutic effects,so as to prove the possibility of disease and reflux related to the diagnosis of suspected reflux.Therefore,the correct diagnosis and treatment of laryngopharyngeal reflux disease is a major problem that Department of ENT doctors need to solve urgently.So far,the number of pepsin detection methods mentioned in the literature which can be retrieved at home is the Enzyme-linked immunosorbent assay(ELISA).However,this method requires relatively high preservation conditions for the samples to be tested,and the time required for testing is relatively long.This method has not been used clinically to study the content of pepsin in saliva of many centers and large samples of normal people.The level of pepsin in the saliva of healthy people is not known.Therefore,ELISA can only detect the level of pepsin,but it cannot be used to judge whether the patient has reflux according to the concentration of pepsin,there is still a long way to diagnose laryngophageal reflux disease by ELISA in clinical practice.Now,foreign countries have begun to detect the concentration of pepsin by PEPTEST,which is a more rapid,convenient and safer method to diagnose reflux disease.This study is mainly based on the comparison of the traditional methods(RFS combined with RSI)in the diagnosis of laryngopharyngeal reflux and the PEPTEST in the diagnosis of laryngopharyngeal reflux,and the significance of the traditional diagnosis and the method of detecting pepsin concentration in diagnosing for the diagnosis of laryngopharyngeal reflux,so as to open up a new study for the diagnosis of laryngopharyngeal reflux.Methods:In this study,we selected 50 cases of chronic pharyngitis with symptoms of throat tickle,irritating cough,frequent hawk,foreign body sensation in throat,and throat dryness from January 2017 to October 2017 in our Otorhinolaryngology-Head and Neck Surgery Clinic.The patients were examined by electronic laryngoscopy,reflux index score(RFS)scores,and reflux symptom index(RSI)scores,and the concentration of pepsin in saliva/sputum was detected by PEPTEST method.The subjects were divided into the laryngopharyngeal reflux group and the non laryngopharyngeal reflux group with RFS≥ 7 and RSI≥ 13,the PEPTEST method was used to detect the concentration of pepsin in the saliva/sputum,and to know the pathological reflux and physiological reflux occurred in the laryngopharyngeal reflux and non laryngopharyngeal reflux group,and to observe the the incidence of the laryngopharyngeal reflux in the chronic pharyngitis.The clinical significance of the PEPTEST method in the diagnosis of laryngopharyngeal reflux was compared with that of the traditional method in the diagnosis of the sensitivity and accuracy of the laryngopharyngeal reflux.This experiment was approved by the ethics committee of Nanjing general hospital.The consent of the patients and their family members was obtained from the study.All the subjects had signed informed consentResults:1.There was no significant difference in gender composition ratio,age,weight and height between two groups in the reflux group and the non-reflux group.2.In these two groups,there are statistical significance about the difference value of pepsin contribution between morning and 1h after lunch,and between morning and when its symptoms are obvious.3.The pepsin concentrations in reflux group and reflux group were significantly different at the same time;4.The distribution of pepsin contribution and RSI showed a linear correlation on scatter diagram,when it’s in the morning,1h after lunch or its symptoms were obvious and the correlation was statistically significant;the distribution of pepsin contribution and RFS shows a linear correlation on scatter diagram,when it’s in the morning,1h after lunch or its symptoms are obvious and the correlation was statistically significant5.The sensitivity of the diagnostic method for detection of pepsin concentration by the PEPTEST was 94.11%and the specificity was 83.33%.Both methods have a general intensity consistency.Conclusion:1.The detection method of pepsin content in saliva/sputum and the RSI combined with RFS method have consistency in the diagnosis of laryngopharyngeal reflux disease.The detection method of pepsin content in saliva/sputum could be used as an effective method for diagnosing laryngopharyngeal reflux disease and could replace the RSI combined RFS method.2.The diagnostic method of the concentration of pepsin by the PEPTEST was a new method for diagnosing the laryngopharyngeal reflux.It could determine the occurrence of reflux events and distinguish the occurrence of reflux events between pathological reflux and physiological reflux.It had the advantages of safety,rapidness,and distinguishing the nature of reflux and was more suitable for clinical use.