Based on fungal morphology (characteristic fruiting heads and hyphal branching patterns) and reports in the literature, the fungal organisms are usually an Aspergillus sp., with Aspergillus fumigatus being the most common. Aspergillus spp. have characteristic fruiting heads and hyphal branching patterns (Figure 3). The fungi are typically accompanied by suppurative inflammation. Changes such as hyperplasia and metaplasia are usually present in the adjacent epithelium, and there is often acute to chronic-active inflammation in the associated underlying lamina propria.
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