Rhinosinusitis and asthma

Chronic rhinosinusitis (CRS) is frequently associated with and has a clear impact on asthma. In this chapter, we describe the current knowledge in this common condition, including state of art diagnosis and treatment, results of recent research findings and insights into new perspectives. CRS implies long-term inflammation of nasal and paranasal cavities. It is defined based on its symptoms, confirmed by endoscopy and/ or imaging. In fact, CRS is divided into two distinct entities due to its endoscopic appearance: with and without nasal polyps (CRSwNP and CRSsNP). While Th1 lymphocytes, IFN-γ, and TGF-β play an important role in CRSsNP, Th2 lymphocytes, IL-5 and a deficit in TGF-β are crucial in CRSwNP. Thus, remodeling and inflammatory patterns clearly differ in the disease entities. Moreover, Staphylococcal enterotoxins are able to function as superantigens and massively activate T-cells and B-cells in CRSwNP patients, resulting in polyclonal IgE formation. This activation of the immune system can give rise to other manifestations of inflammation, such as asthma. Indeed, CRSwNP and asthma frequently co-occur and share many pathophysiological attributes, leading to the concept of united airways disease. Treatment of CRS is based upon severity and includes symptomatic treatment, nasal corticosteroids, long-term antibiotics and/or a short course of oral corticosteroids. Surgery is an alternative when patients do not satisfactorily respond to medical treatment. Novel, promising treatment modalities are being developed thanks to the advances in CRS research