Allergic fungal sinusitis

Allergic fungal sinusitis is a challenging problem. It probably results from entrapment of fungal forms in the sinuses of patients with associated atopy. The characteristic clinical picture is pansinusitis (unilateral more than bilateral) and polyposis, recurrent despite previous surgeries. Radiographic studies present a characteristic pattern. At surgery, in addition to polyps and pansinusitis, the most distinctive finding is allergic mucin. This tenaceous, dark, rubbery material contains numerous eosinophils and Charcot-Leyden crystals, and fungal stains show the presence of noninvasive hyphae. Fungal cultures may or may not be positive. The differential diagnosis of allergic fungal sinusitis includes allergic mucin sinusitis, mycetoma, or saprophytic fungal growth within a diseased sinus. Treatment involves adequate surgical exenteration, the use of corticosteroids (topical and systemic), and postoperative cleaning. Despite warnings to the contrary, immunotherapy with fungal antigens may be of significant benefit.