Sinobronchial Allergic Mycosis: Eosinophil-derived
Other data also suggest that the pathogenesis of these diseases is similar. In a review of the histopathologic features of AFS, Kahn et al noted the histopathologic similarities between ABPM and AFS. There is evidence for the active contribution of both eosinophil-derived and neutrophil-derived products, including eosinophil major basic protein and neutrophil elastase, like that seen in late-phase cutaneous reactions. Their findings support earlier suggestions that ubiquitous fungal spores induce a robust, IgE-mediated inflammatory response that induces the viscous mucous secretions these patients experience. Eosinophil-derived and neutrophil-derived toxic proteins have the capacity to induce tissue destruction leading to the layers of eosinophil and epithelial cellular debris that are component parts of the allergic mucin other canada health and care mall. The mucin obstructs the airways leading to ongoing infection. Since the presence of only small quantities of fungal hyphae in the airway is necessary to initiate the eosinophilic inflammatory process associated with the disease, obstruction to normal drainage of the airway seen in both asthma and chronic sinusitis could be a common feature predisposing an individual to the development of these conditions.
Most, if not all, patients with AFS and concomitant severe lower airways obstruction could be at risk for the development of ABPM. We suspect that the diagnosis of coexistent disease may sometimes be overlooked since at least 50% of patients with AFS have asthma, which is one of the diagnostic criteria for ABPM. Why all atopic individuals who demonstrate fungal-specific IgE do not develop one or both of these diseases is unclear. This could reflect a dose-response relationship between obstruction and disease or a more robust IgE-mediated inflammatory response in those patients who develop this form of fungal hypersensitivity. Most patients with AFS have evidence of a fungal-specific IgE response to multiple fungal allergens, as was the case with our pa-tient. In our patient, Chrysosporium, a fungus previously implicated in the pathogenesis of AFS, grew from a culture of surgical material obtained from the sinuses and appeared to be the culprit allergen.