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

OBJECTIVE: 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. METHODS: 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. RESULTS: 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%). CONCLUSIONS: RSI and RFS are not specific for reflux laryngitis and are more likely to induce a false diagnosis if not used with diligence.