Sputum periostin in patients with different asthma phenotypes

Abstract Background Asthma is a common respiratory condition causing symptoms such as cough, chest tightness and wheezing that are triggered by factors as exercise, allergens and viral infection. Asthma is characterized by airflow limitation, airway hyper-responsiveness and bronchial inflammation. Aim of the work to identify the different phenotypes in a group of asthmatic patients; and to evaluate the role of periostin in bronchial asthma and its different cellular phenotypes and its correlation asthma severity. Subjects and Methods This observational cross-sectional study was conducted on 96 adult asthmatic patients. They were classified into two groups: group (A) 48 patients with severe asthma (persistent airflow limitation), group (B) 48 patients with mild to moderate asthma according to (GINA 2016) criteria attending the Allergy and Clinical Immunology outpatient clinic, Ain Shams University Hospitals. The study also included 10 healthy controls of matched age and sex group. Results sputum periostin levels in asthmatic patients are higher than its levels in healthy controls. Sputum eosinophil percentage in asthmatic patients is higher than those in healthy controls. Sputum periostin levels in patients with severe asthma were found to be higher than sputum periostin levels in patients with mild to moderate asthma. There is high positive correlation between sputum periostin and asthma severity and age and there is negative but significant correlation between sputum periostin and (FEV1) and it is found to be correlated with duration of asthma and pattern of (PFT) abnormality (higher in mixed pattern) and sputum eosinophilia. Conclusion Sputum periostin is correlated with asthma severity and eosinophilic asthma. Periostin is considered to be an important biomarker for severe asthma and eosinophilic phenotype of asthma.