The links between chronic rhinosinusitis and asthma

Chronic rhinosinusitis (CRS) and asthma are two leading causes of morbidity with many shared clinical features. Their relationship has initially been linked by the atopic pathway. However, understanding of the true pathophysiology of each of these conditions is still under investigation. Recent studies have described new common pathogens, such as fungi and Staphylococcus aureus, as well as disease biomarkers such as nitric oxide and interleukin (IL)-17A, involved in both asthma and CRS pathophysiology. These new discoveries offer insight into understanding these upper and lower airway diseases and may potentially affect treatment management. In the following review, we intend to provide an overview of the recent developments in the relevant areas of research within the past year. Reactions to fungal stimuli and superantigens, as well as biomarkers such as nitric oxide and IL-17A, may play a role in the pathogenesis of asthma and CRS and may explain their historic relationship.