Allergic fungal sinusitis involves multiple sinuses and occurs in immunocompetent individuals who usually have a history of multiple preceding sinus surgeries and nasal polyposis. Aspergillus species and less often Curvularia lunata are the usual etiologic agents. Histology of nasal secretions in these patients reveals thick mucin, eosinophils, and few fungal hyphae. Sinus imaging typically shows involvement of multiple sinuses with hypodense areas, occasional calcifications, and occasional bony erosions. Criteria for the diagnosis of allergic fungal sinusitis are immunologic and are identical to those listed for allergic bronchopulmonary aspergillosis, which may complicate allergic fungal sinusitis.
Treatment includes surgical drainage and debridement as well as corticosteroid therapy.
Affected children are often asymptomatic, although cough and hemoptysis may be reported. Management is controversial and may range from watchful waiting for asymptomatic and otherwise healthy children to surgical resection in patients with symptoms. 233.3 Invasive Disease Invasive Aspergillus infection is characterized by hyphal infiltration of vascular structures, thrombosis, and focal necrosis. Primary invasive disease may occur at any site in which airborne conidia may colonize and germinate, such as the respiratory tract or skin. In the severely neutropenic child, dissemination follows direct extension from the primary site and hematogenous seeding of distant sites.