Exploring Treatment Approaches for Asthma and Chronic Rhinosinusitis With Nasal Polyps

Targeted biologics for treating asthma are now being explored for chronic rhinosinusitis with nasal polyps (CRSwNP) and highlight the need for improved classification and diagnosis of different presentations of the disease to improve therapeutic efficacy, according to the International Journal of Studies in Natural and Medical Sciences.  

Traditionally, CRS has been classified as either CRS with nasal polyps (CRSwNP) or CRS without nasal polyps (CRSsNP). CRSwNP is associated with more severe symptoms and a higher prevalence of asthma. At the cellular level, CRSsNP is characterized by TH1 inflammation, while CRSwNP is characterized by TH2 inflammation. However, recent research suggests that CRS may be better classified based on endotypes or clusters that reflect specific pathological mechanisms. 

CRSwNP is also characterized by a loss of barrier function in the nasal epithelium, which reflects a general inflammatory process. Glucocorticoid-based treatment is the most common approach, but response varies, and some patients are resistant to steroid therapy. 

Both asthma and CRS are characterized by type 2 inflammation, involving cellular infiltration and the production of type 2 cytokines. Eosinophilic inflammation is significant in severe forms of asthma. IgE antibodies play a role in both diseases, influencing immune and structural cells. IL-5- and IL-13-producing cells, such as ILC2s, are increased in severe asthma and CRSwNP. Airway remodeling, including goblet cell hyperplasia and subepithelial fibrosis, occurs in asthma and CRS. 

Cytokines are promising biomarkers for CRS diagnosis and treatment. CRSsNP is associated with a TH1 or TH17 phenotype, while CRSwNP is characterized by a TH2 microenvironment. Various cytokines, such as TGF-β, IL-6, IL-8, and IL-17, are expressed in CRSsNP, while IL-4, IL-5, IL-13, IL-25, and IL-33 are elevated in CRSwNP. These cytokines contribute to inflammation, mucus production, eosinophilia, and airway hyper-responsiveness. Anti-cytokine agents used in asthma treatment may also have a role in treating TH2 inflammation in CRS. IL-25 appears to play a regulatory role in the IL-13 cascade. 

“Taking into account the significant proportion of patients in which the two diseases coexist, and the common underpinned cellular and molecular inflammatory network, at least in type 2 forms, it was believed that by using the available biological agents, we could obtain an equivalent therapeutic effect for both asthma and CRS,” said researchers.  

CRS is a complex disease with diverse presentations and underlying mechanisms. Improved classification and understanding of the pathophysiology of CRS, particularly CRSwNP, will aid in developing more effective therapies. Cytokines, including IL-4, IL-5, IL-13, and IL-25, are important in driving the inflammatory processes in CRS and may serve as potential targets for treatment. Further research is needed to fully elucidate the role of cytokines in CRS and their therapeutic potential. 

Reference 

Khabibullayev, TU. Asthma and chronic rhinosinusitis with nasal polyps: exploring common pathways and treatment approaches. International Journal of Studies in Natural and Medical Sciences. 2023;2(5). ISSN (E): 2949-8848.