Updates in the Classification of Fungal Sinusitis

Purpose of review: This review aims to present the current classification schema for fungal rhinosinusitis, highlight current topics of interest, and identify potential areas for improvement and further research. Recent findings: There have been recent concerns that the allergic fungal rhinosinusitis (AFRS) criteria may be too stringent, leading to missed diagnoses. Additionally, many individual components of the AFRS criteria are non-specific. A “subacute” or “intermediate” category for invasive fungal sinusitis (IFS) has been proposed in addition to acute and chronic classifications. A new “microinvasive” variant of invasive fungal sinusitis has also been suggested. Recently, there have been reports of progression from non-invasive forms of fungal sinusitis to IFS in immunosuppressed patients. Summary: While diagnostic criteria have been published and widely accepted, there is a possibility that fungal sinusitis is a spectrum of disease both in terms of aggressiveness and invasiveness. There is a vast opportunity for multi-institutional studies, translational research, and updates to the classifications and guidelines for fungal sinusitis.