[Two cases of allergic fungal rhinosinusitis with bone destruction]

We report herein two cases of allergic fungal rhinosinusitis accompanied by bone destruction of the adjacent nasal sinuses. The first case involved a 21-year-old man who presented with left exophthalmos. Computed tomography (CT) showed soft tissue lesions in the left paranasal sinuses and destruction of the left lamina papyraceae, as well as infiltration of the lesion into the orbit. In the second case, a 39-year-old man, CT showed bone destruction of the skull base and medial wall of the left orbit. In both cases, total serum immunoglobulin (Ig)E level was >1000 IU/mL and fungus-specific IgEs were increased. Fungal hyphae were identified within the mucus on histopathological examination in both cases; however, no fungal invasion of the mucosa was apparent. Final diagnosis was allergic fungal rhinosinusitis (AFRS) in both cases. AFRS is a relatively new disease concept that was proposed in the early 1980s, with disease characteristics very similar to eosinophilic rhinosinusitis. Occasionally, AFRS must be differentiated from malignant disease or invasive fungal rhinosinusitis, so an understanding of the clinical features is important.