Fungus culture of the nasal secretion of chronic rhinosinusitis patients: seasonal variations in Daegu, Korea.

BACKGROUND

The role of fungi in the pathogenesis of chronic rhinosinusitis (CRS) is being increasingly recognized. The presences of fungal spores are a necessary condition for fungal sinusitis, and fungal spore counts vary widely, both geographically and seasonally. The aim of this study was to characterize fungal seasonal variation in the nasal cavity of CRS patients and to compare it with histologic types of nasal polyps.

METHODS

One hundred eight patients with a clinical diagnosis of CRS with polyps were enrolled in this study for 1 year. Nasal secretions were obtained by aspiration and cultured to identify fungi. Nasal polyps were divided into four histologic types: eosinophilic, fibroinflammatory, seromucinous, and atypical.

RESULTS

Positive cultures for fungi were obtained in 60 of 108 (63.0%) CRS patients, and 28 of 45 (62.2%) normal volunteers. Fungus culture rates were higher during summer and fall. Cladosporium, Aspergillus, Alternaria, and Penicilium were frequently isolated from CRS patients and normal volunteers. The most common histologic type was the fibroinflammatory type (60.2%), although in the summer and fall the proportion of the eosinophilic type increased.

CONCLUSION

Fungi were commonly cultured during a hot and humid environment, during summer and fall, and cultured organism types were found to be seasonal dependent. Histologic types of nasal polyps appear to be associated with fungal culture rate, organism type, and seasonal variations.