ABSTRACT
Background:There are few biomarkers that can be easily accessed in clinical settings and may reflect refractory Th2-eosinophlic inflammation and remodeling of the asthmatic airways. Serum periostin may be one such biomarker to aid our understanding of the patho-bio-physiology of asthma and exercise induced asthma. The aim of the study is to explore the relationship between serum periostin level and exercise induced bronchoconstriction in asthmatic children.Materials and Methods: This cross-sectional study was carried out on (90) children both sexes aged from 6 to 15 years including, (60) children with bronchial asthma and (30) children were enrolled as control group in the period from January 2018 to January 2019. Patients were randomly classified into two groups: I) Patient group: divided into 2 groups according to standardized treadmill exercise challenge test: Group A: (30) asthmatic children with positive test. Group B: (30) asthmatic children with negative test. II-Control group: (30) children apparently healthy with no personal or family history of asthma. All children were subjected to the following Investigations: Chest x-ray, pulmonary functions tests (FEV1& PEFR) except controls, Laboratory investigations as CBC and Serum periostin level Results:The mean values of both the percentage of PEFR and FEV1 after exercise in group A were significantly lower than those in group B and the percentage of PEFR and FEV1after exercise in each group were significantly lower than the percentage before exercise in the same group. The mean value of eosinophilic count in group A was significantly higher than (group B and control group) and the mean value of eosinophilic countin group B was significantly higher than control group. The mean value of serum level of periostin in group A was significantly higher than (group B and control group), however, there was no significant difference between group B and control group as regard to serum level of periostin.Chest tightness, cough and wheezes after exercise and eosinophilic count in patients with high serum periostin level were significantly higher than patients with low serum periostin level, and both PEFR and FEV1after exercise in patients with high serum periostin level were significantly lower than patients with low serum periostin level. Also the normal serum periostin levels vary among different age groups.Conclusion:Serum periostin level can be considered as a useful biomarker for diagnosis of Exercise induced bronchospasm (EIB) in asthmatic children especially when lung function test cannot be done However, cautious is required in evaluating serum periostin levels in children because it varies with age.