[Allergic fungal sinusitis].

Allergic fungal sinusitis (AFS) is considered an allergic inflammation against fungus, and has been reported to be refractory, with very high recurrence. In Europe and the United States, AFS incidence is reported from 4% to 7% in patients with chronic sinusitis undergoing endoscopic sinus surgery (ESS). In Japan, however, only 5 patients, including ours have been reported, making AFS very rare in Japan. We prospectively studied the incidence, pathogenesis and diagnosis of AFS in Japan among 102 patients with chronic sinusitis who underwent ESS. Four cases (3.9%) were diagnosed with AFS based on the criteria of Bent and Kuhn. This incidence is slightly lower than that reported in Europe and the United States. We report the diagnosis, treatment, and course in 4 AFS patients. Of these, an allergen provocation test against detected fungus was conducted in 2 from whom informed consent was obtained. In the immediate phase, positive reactions were observed. Immunoglobulin E (IgE) antibody-mediated type I allergy may be involved in the pathogenesis of AFS.