The impact of rhinosinusitis on asthma

The nasal cavity, paranasal sinuses, and lungs are considered separate organs of the respiratory tract. However, a growing body of evidence links the upper and lower airways. For example, the coexistence and impact of allergic and nonallergic rhinitis on asthma is now documented. In addition, inflammation of the nose (rhinitis) commonly is associated with inflammation of sinuses (sinusitis), as reflected in the term rhinosinusitis. In this paper, we review the impact of rhinosinusitis on asthma as it relates to the links between allergic and nonallergic rhinitis and asthma; viral upper respiratory tract infections and asthma; allergic and nonallergic infectious/inflammatory rhinosinusitis and allergic and nonallergic hyperplastic rhinosinusitis and asthma; and the aspirin-exacerbated respiratory disease syndrome and asthma.