Periostin as a biomarker for the diagnosis of pediatric asthma.

Background There are some biomarkers for asthma diagnosis but they are often difficult in clinical use, particularly in pediatric cases. Periostin is an extracellular matrix protein, upregulated in response to IL-4 or IL-13. Serum periostin is expected to be used as a non-invasive biomarker for asthma diagnosis and management. Methods Twenty-eight children with asthma (BA) and 27 children without asthma (patients with pectus excavatum, etc. as control group) aged 6–16 years were included. Bronchial asthma was diagnosed according to International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Fractional exhaled nitric oxide (FeNO), lung function, blood eosinophil counts, total immunoglobulin E (IgE) levels, and serum periostin levels were assessed. Results were compared between BA and controls. Asthma diagnostic accuracies were calculated using receiver operating characteristics (ROC) curve analyses. Results Serum periostin levels in the BA group were significantly higher than those in the control group [medians (with interquartile ranges), 134.0 (116.3–166.3) vs. 112.0 (97.0–132.0) ng/ml; p = 0.012]. The area under the ROC curve (AUC) for periostin, FeNO, and eosinophil counts were 0.70, 0.72, and 0.84, respectively. After the exclusion of controls with pectus excavatum, AUC for periostin, forced expiratory volume in 1 s (FEV1), and maximum mid-expiratory flow rate (MMF) were 0.75, 0.74, and 0.80, respectively. Conclusion Serum periostin levels were significantly higher in children with asthma. ROC AUC values for periostin were equivalent to conventional biomarkers, including FeNO levels and lung function testing, indicating the utility of serum periostin levels in diagnosing asthma in children.