To determine whether detection of pepsin in the saliva could be useful for diagnosing laryngopharyngeal reflux (LPR).

30 patients having LPR with reflux symptoms index scale (RSI)＞13 and a reflux symptoms index scale (RFS)＞7 were selected. 50 healthy adults were randomly recruited as subjects,and the saliva was collected into 1.5ml sterile EP tubes after awaking in the morning,and the last saliva in the evening.and the tubes were placed in a refrigerator with in half an hour. The level of pepsin in saliva was measured by human pepsin ELISA kit.

Among the 30 subjects,the average content of pepsin in morning saliva was 122.964 (49.224-239.004) ng/ml. The average content of pepsin in evening saliva was 98.116 (51.116-143.792) ng/ml. Among the 50 subjects, the average content of pepsin in morning saliva was 14.57 (2.62-32.04) ng/ml. The average content of pepsin in evening saliva was14.22 (7.72-20.3) ng/ml. There were statistical differences between the laryngopharyngeal reflux group and healthy group in the saliva and pepsin level (P＜0.01).

Pepsin strip detection has the advantages of non-invasive,cheap and easy to operate. As an objective method for early diagnosis of laryngopharyngeal reflux, pepsin strip detectionis feasible Which should be popularized.