Schizophyllum commune: an unusual isolate from a patient with allergic fungal sinusitis.

We describe the first case of allergic fungal sinusitis (AFS) associated with Schizophyllum commune. Histological diagnosis was made on the mucinous material from the sinus which contained eosinophils, fungal hyphae and Charcot-Leyden crystals. The fungal isolate was identified as S. commune on the basis of its colonial morphology and minute peg-like outgrowths from vegetative hyphae and clamp connections. The optimal treatment of AFS is not known but may involve surgical debridement followed by systemic corticosteroids, gradually reduced, with the patient being maintained on inhaled corticosteroids. Oral itraconazole could be added to the regimen of those patients in whom frequent recurrences occur after debridement or when there is histological evidence of severe pressure erosion.