The diagnosis of CRSsNP and distinguishing it from allergic rhinitis is difficult. Yet, early detection of CRSsNP is essential to prevent progressive and severe chronic rhinosinusitis. We aimed to compare the diagnostic accuracy of symptoms, endoscopy, and imaging signs of CRSsNP and allergic rhinitis -only phenotypes.

The present study is a prospective controlled follow-up study.

Radiologic Lund–Mackay score, duration of symptoms, visual analog scale scores of symptoms, and Sinonasal Outcome Test 22 were significantly higher in the CRSsNP group than allergic rhinitis control groups. These factors also correlated in part with each other. The endoscopic score did not connect with other factors, nor did it differ between CRSsNP and allergic rhinitis groups. The highest area under curve value was demonstrated for visual analog scale score of facial pain/pressure (0.93), and score ≥4/10 showed 60% sensitivity and 95% specificity for detecting CRSsNP group. Radiologic signs of the obstructed stomatal complex showed 100% specificity and 38% sensitivity for detecting the CRSsNP group.

The study concluded that the CRSsNP phenotype could be primarily distinguished from allergic rhinitis by higher facial pain/pressure score and secondarily by radiologic signs of obstructed ostiomeatal complex and higher Lund–Mackay score. The endoscopic score has limited value in distinguishing CRSsNP from allergic rhinitis.