Endotypes of chronic rhinosinusitis: Impact on management.

Following the trend in asthma, endotypes for chronic rhinosinusitis with nasal polyps have been established, with type 2 immune reactions representing >80% of nasal polyp cases in Europe and the United States. Endotyping is without doubt useful to predict the natural course of disease, to determine pharmacotherapy and the extent of surgery, and lately also to select patients for treatment with type 2 biologics. However, with the opening of this new era of treatment, limitations of the current possibilities in subgrouping patients also became apparent, as (1) mixed endotypes often can be found and (2) predictions as to the best biologic to be used in an individual patient are not yet possible. Some of the questions to address in the near future are discussed.