Neutrophilic asthma is a multifaceted phenotype of severe and persistent asthma, characterized by frequent exacerbations, leading to hospitalizations, due to near-fatal asthma, fixed airflow obstruction, poor response to corticosteroids, and patient have worse quality of life, its development is driven by the participation of various immune cells and molecules. Neutrophilic asthma is caused by the interaction between genetic, environmental, innate and adaptive immune factors. Among these factors, air pollution, smoking, viral, bacteria, fungal infections and obesity contribute to the exacerbation of this type of asthma, by promoting Th17-type cell inflammation, increasing the secretion of Th17-related cytokines and chemokines, which induces the activation of neutrophils and their recruitment into the sites of inflammation. The molecular mechanisms underlying the severity of neutrophilic asthma is still not well clear or understood, making the diagnosis and treatment of this type of severe asthma an extremely challenging. The discussion of the pathophysiology, mechanism, characteristic, mediators, risk factors, biomarkers and steroid resistance of neutrophilic asthma, in this paper may provide some direction for the prevention, diagnosis and treatment of severe neutrophilic asthma. Hence this phenotype of asthma requires specific therapeutic interventions aimed at prevention and reducing airway remodeling.

Keywords: Asthma, Neutrophil.