Allergic Fungal Sinusitis: Masquerade Syndrome and Delay in Diagnosis

Allergic fungal sinusitis is a chronic inflammatory upper respiratory disorder characterized by a type I immediate hypersensitivity reaction to fungal antigens. It may present with nasal polyps, sinus obstruction, and elevated serum IgE. Histopathology may; demonstrate the presence of fungal hyphae and chronic inflammation. In its most severe forms, AFS may lead to orbital invasion, compressive optic neuropathy and intracranial extension