Fungal sensitization in nasal polyposis.

BACKGROUND There are indications that polyposis is somehow related to allergic phenomena. Fungal sensitization in substantial proportions of patients has been cited as a trigger of inflammatory mechanisms involving either an immunoglobulin (Ig) E-mediated reaction to fungal colonization or fungal invasion of tissues. OBJECTIVE To confirm whether fungi were involved in the development of polyposis by examining sensitivity to fungal allergens and potential local contamination by fungal species. METHODS We performed a study of 190 patients with polyposis and 190 controls in which we compared the results of skin prick tests to 12 fungi, total IgE, and specific IgE to 15 fungal extracts and nasal fungal cultures. RESULTS The specific fungi eliciting a reaction from the largest proportion of patients in the skin prick tests were Fusarium solani (13.7%), Penicillium frequentans (12.6%), Trichophyton mentagrophytes (11.1%), and Candida albicans (8.4%) (P < .001). The proportion of individuals that tested positive for fungal-specific IgE was 22.4% (38/170) for patients and 10.1% (19/189) for controls (P = .04). The respective proportions of positive responses to fungal cultures were 58.7% and 60%. Furthermore, no significant differences between patients and controls were found for the results of in vitro tests with cultured fungal allergens. CONCLUSIONS Although the patients with polyposis exhibited sensitization to fungal allergens, we found that nasal colonization by fungi was similar in patients and the general population. We were also unable to find a correlation between a positive response to the cultures and the presence of fungal allergen-specific IgE. It therefore seems that nasal colonization by fungi does not induce fungal sensitization.