AFRS review Pathogenesis Underling or acquired hypersensitivity to certain fungal antigens trapping of inhaled fungal antigen within the nasal cavity & sinuses (5.7x10 7 spores/day) Early and late-phase allergic inflammation with recruitment of activated eosinophils and lymphocytes Mediator release with epithelial damage, mucosal edema, ostial obstruction stasis of secretion, polyposis, Sinus expansion and bony erosion 2 nd bacterial infection direct contact of fungal antigens with inflammatory cells aggravate the inflammatory process

symptoms facial pressure, headache, nasal stuffiness, discharge, and cough. intractable sinusitis and nasal polyposis. proptosis or eye muscle entrapment, atopy and multiple surgeries Diagnostic criteria (Bent&Kuhn) type 1 hypersensitivity nasal polyps characteristic CT findings positive fungal stain or culture allergic mucin Eosinophilic fungal rhinosinusitis Eosinophilic mucin rhinosinusitis

GMS stain of nasal secretions

Treatment of choice generally is surgery Systemic steroids may be indicated: prednisone (0.5 mg/kg) Topical nasal steroids are helpful postoperatively. Aggressive nasal salt-water washes are recommended. Immune therapy for specific allergens is controversial

AFRS cycle Inhaled fungus Proliferation Antigen exposure Type I & III reaction Mast cell & eosinophil degranulation Immune complex formation? Mucosal edema & inflammation Stasis of secretion Decreased ventilation & drainage Anatomic obstruction Bacterial sinusitis surgery Saline irrigation Immunotherapysteroid Genetic predisposition (atopy)

Hypothetic pathogenesis of EFRS Underling or acquired hypersensitivity to certain fungal antigens trapping of inhaled fungal antigen within the nasal cavity & sinuses direct contact of fungal antigens with epithelial cells and release cytokine (TSLP, IL-6, IL-8, GM- CSF, etc) Activated dendritic cells & T- lymphocytes polarization Increase tissue eosinophils and phagocytic activity eosinophil migrate to nasal and sinus cavity to attack fungal elements and release granule protein mucosal epithelial cells damage with mucosal edema, ostial obstruction, polyposis direct contact of fungal antigens with inflammatory cells aggravate the inflammatory process develop secondary bacterial infection

Treatment of EFRS based on pathophysiology Surgery temporary decrease antigenic load Steroid decrease inflammatory response Antifungals (topical) decrease allergenic load