[Application of reflux symptom index in diagnosis of allergic patients with laryngopharyngeal reflux].

Objective:To explore the diagnostic value and optimal diagnostic threshold of reflux symptom index(RSI) in allergic patients with laryngopharyngeal reflux. Method: All the adult allergic patients with respiratory tract symptoms completed the RSI with the consent of the patients. A total of 150 patients with RSI＞13 were screened out. The LPR patients were confirmed by 24 h pH-metry of pharyngo-laryngoesophageal (allergic group). The same number of non allergic laryngeal reflux patients were selected as control group (non allergic group). The ratio of RSI＞13 to LPR was calculated. The total score of RSI and each score were compared between the allergic group and the non allergic group. ROC curve was used to analyze the highly suspicious RSI score thresholds for patients with reflux laryngitis. Result:Only 53(35.33%) of 150 patients with RSI＞13 were diagnosed as LPR after 24 h pH-metry test in allergic patients. Among the 9 symptoms of RSI, the scores of 6 symptoms in allergic group were significantly higher than those in non allergic group(P<0.05). The average RSI score of allergic group was 23.57±3.17. The average RSI score of non allergic group was 17.57±2.64. The total score of allergic group was higher than that of non allergic group(P<0.05). According to the RSI score ROC curve of allergic group, the area under 95% confidence interval curve was 0.815. RSI had certain diagnostic accuracy for allergic patients with LPR. The best critical value of RSI score for allergic patients with LPR was 18, the sensitivity was 94.3%, and the specificity was 56.7%. Conclusion:RSI can be used to screen allergic patients with LPR, diagnostic score threshold RSI＞18 points, has a certain diagnostic accuracy.