Comparison of bacterial examinations between eosinophilic and neutrophilic chronic rhinosinusitis with nasal polyps

Conclusion: We found no significant differences in the bacterial features of the maxillary sinuses between eosinophilic and neutrophilic chronic rhinosinusitis (CRS) with nasal polyps. Objectives: Since neutrophilic CRS is often influenced by a predisposition to bacterial infection, and eosinophilic CRS is likely to be developed by allergic antigens, differences in the microbiology between the two pathologies of CRS can be expected. The present study was designed to investigate the bacterial findings from the maxillary sinus in eosinophilic and neutrophilic CRS. Methods: Seventy patients with CRS with nasal polyps were divided into eosinophilic and neutrophilic types based on histopathological observations of the nasal polyps. The specimens for bacterial culture were obtained from the maxillary sinus during endoscopic sinus surgery. Results: In all, 29 and 41 patients were classified as having eosinophilic and neutrophilic CRS with nasal polyps, respectively. The isolation rate of bacteria showed no significant difference between eosinophilic (90%) and neutrophilic CRS (98%). Aerobic bacteria were found in 25 patients (86%) with eosinophilic CRS, which was not significantly different from that in neutrophilic CRS (40 patients, 98%). The isolation rate for aerobic and anaerobic bacteria showed no significant differences.