Using RSI and RFS scores to differentiate between reflux-related and other causes of chronic laryngitis

To establish if the Reflux Symptom Index (RFI) and the Reflux Finding Score (RFC) can help establish the differential diagnosis in patients with distinct causes of chronic laryngopharyngitis.

A group of 102 adult patients with chronic laryngopharyngitis (Group A - 37 patients with allergic rhinitis; Group B - 22 patients with Obstructive Sleep Apnea (OSA); Group C - 43 patients with Laryngopharyngeal Reflux (LPR)) were prospectively studied. Chronic laryngitis was diagnosed based on suggestive symptoms and videolaryngoscopic signs (RSI ≥ 13 and RFS ≥ 7). Allergies were confirmed by a positive serum RAST, OSA was diagnosed with a positive polysomnography, and LPR with a positive impedance-PH study. Discriminant function analysis was used to determine if the combination of RSI and RFS scores could differentiate between groups.

Patients with respiratory allergies and those with LPR showed similar and significantly higher RSI scores when compared to that of patients with OSA (p < 0.001); Patients with OSA and those with LPR showed similar and significantly higher RFS scores when compared to that of patients with Respiratory Allergies (OSA vs. Allergies p < 0.001; LPR vs. Allergies p < 0.002). The combination of both scores held a higher probability of diagnosing OSA (72.73%) and Allergies (64.86%) than diagnosing LPR (51.16%).

RSI and RFS are not specific for reflux laryngitis and are more likely to induce a false diagnosis if not used with diligence.