The Clinical Relevance of Differential Cell Counts in Induced Sputum and its Relationship with Various Forms of Asthma

The article provides an overview of modern concepts of induced sputum analysis and a description of the methodology and protocols for the collection of induced sputum in adults and children. This paper describes the cellular composition of induced sputum in healthy people and in patients with asthma in detail, analyses the significance of the sputum eosinophil count as a prognostic and diagnostic criterion and the role of other cells, such as neutrophils, macrophages, basophils. In this article, we review a number of asthma biomarkers of inflammation and remodeling of the airways in asthma, which can be determined in sputum (anaphylatoxin C3a, clusterin, periostin). In addition, we summarize recent data about asthma phenotypes and describe the possibilities of using induced sputum analysis as a diagnostic and therapeutic tool for personalized anti-inflammatory therapy for asthma.