A case report of allergic fungal sinusitis

Abstract

The first case of allergic fungal sinusitis in Japan is herein reported which was diagnosed based on the findings of a histopathological examination. The patient was a 44-year-old male who had a nasal blockade of the left side. Mucosal thickening, focal areas of high attenuation on the maxillary sinus, and bony erosine of the sinus margin were revealed by CT. On histopathological examination, a number of eosinophils and Charcot-Leyden crystals were observed in the mucin obtained from the sinus. A few filamentous fungal elements were represented in a section of mucin stained with Grocott's method, but the mucosa of the sinus was not invaded by any fungi. The peripheral eosinophil count and specific IgE to any fungal antigens had both increased, and a skin test showed an immediate hypersensitivity response to fungus.
The allergic reaction against fungi, namely type I immune response, is thus considered to play an important role in the induction of disease, which is characterized by a non-invasive fungal proliferation.