Histopathologic difference between sinonasal mucosa and polyp tissue for diagnosing eosinophilic chronic rhinosinusitis

Abstract

This study aims to assess the appropriate site for diagnosing eosinophilic chronic rhinosinusitis (ECRS) by histopathology. Patients with chronic rhinosinusitis with polyps (CRSwNP) were enrolled. Specimens were collected from polyp apex, polyp pedicle, polyp scraping and ethmoid mucosa. Number of tissue eosinophil of the four samples was assessed with intrapersonal comparison for diagnosing ECRS. Correlations with clinical characteristics of ECRS were assessed for each site. Results showed that thirty patients with CRSwNP were enrolled. Polyp apex, polyp pedicle and ethmoid mucosa gave similar results for diagnosing ECRS in 16 patients (53.3%). Median tissue eosinophil was greater in polyp apex (84, IQR: 34-194) and polyp pedicle (96, IQR: 80-320) than ethmoid mucosa (21, IQR: 10-220), p=0.04. Sensitivity for diagnosing ECRS were 100% (95%CI: 47.8 - 100) for polyp apex, 60% (95%CI: 14.7 - 94.7) for polyp pedicle, 80% (95%CI: 28.4 – 99.5) for ethmoid mucosa. Correlations with asthma were significant for polyp pedicle (p=0.05), and ethmoid mucosa (p=0.04) but not polyp apex (p=0.21). Correlations with serum eosinophilia, and eosinophilic mucin were not significant. Tissue eosinophil from polyp scraping only correlated with ehtmoid mucosa. Consequently, density of tissue eosinophil was greater in nasal polyp than ethmoid mucosa. Polyp apex had greater sensitivity for diagnosing ECRS than others. Polyp pedicle and ethmoid mucosa correlated with asthma. Tissue eosinophil from polyp scraping only correlated with ehtmoid mucosa.