Pathogenesis of IAPA
In pending studies that explore the pathogenesis of IAPA and host immune defects, it is likely that damage to the epithelium by influenza and defective fungal host responses in the lung due to influenza and/or inflammatory conditions predispose to Aspergillus disease, similar as what is seen in bacterial superinfections. Furthermore, autopsy studies have shown the presence of sporulating heads of Aspergillus inside the bronchi with invasive growth occurring into the lung tissue. Sporulation could contribute to a high fungal burden and spread of the disease within the lung, thus contributing to the rapid disease progression and extensive lung damage. Other factors that have been implicated in IAPA include the use of corticosteroids and of neuraminidase inhibitors, such as oseltamivir [7, 30]. Ultimately, these insights may aid in identifying patients at risk of IAPA and to design effective antifungal and adjunctive immunomodulatory treatment strategies.