The role of mucosal immunity in fungus ball of the paranasal sinuses

Conclusion: Increased levels of immunoglobulin (Ig)A, plasma cells, and lymphocytes without infiltration of other inflammatory cells suggest that mucosal immunity may play an important role in paranasal fungus ball. Objectives: This study aimed to examine the nasal mucosal immune responses to fungi to understand the pathogenesis of fungus ball. Methods: Five patients with fungus ball of the maxillary sinus were enrolled. Lavage samples were collected from both nasal cavities and the maxillary sinus of the affected side. Mucosal samples were taken from both inferior turbinates and the maxillary sinus of the affected side. Interleukin (IL)-4, interferon (IFN)-γ, and IgA levels in the lavage samples were measured. Cells were counted on the lamina propria of mucosa under an electron microscope. Results: No significant differences in levels of IL-4 and IFN-γ were observed between the three groups of lavage samples. However, a significant rise in IgA levels was observed in the lavage samples from the nasal cavity and maxillary sinus of the affected side compared with that of the contralateral nasal cavity. Infiltration of plasma cells and lymphocytes in mucosal samples from the inferior turbinate and maxillary sinus of the affected side was significantly increased compared with that from the contralateral inferior turbinate, but other inflammatory cells were few and showed no difference.