Abstract:Objective To develop a mouse model of acute bacterial rhinosinusitis. Method 35 Swiss mice were inoculated intranasally with type 3 encapsuled Streptococcus pneumoniae solution. The controls (5 Swiss mice) were inoculated with sterilized saline. The histological sections of the nasal cavities and nasal sinuses were stained with hematoxylin-eosin. Neutrophil clusters in the nasal cavities and nasal sinuses were checked. Results There was significant red blood cells exudation before the 5th day of inoculation. Then on day 8, neutrophil clusters were examined and by day 11 and 14 the number of neutrophil clusters gained its peak. The amount of inflammation disappeared by day 28. Conclusions Streptococcus pneumoniae induces acute bacterial rhinosinusitis in Swiss mouse, and it can be used as an animal model of acute bacterial rhinosinusitis.