Significance of total serum IgE in children with lower respiratory infections due to respiratory syncytial virus

PURPOSE: Respiratory syncytial virus (RSV) is known to induce Th2 immune response with increased IgE production. We investigated serum IgE levels in RSV bronchiolitis/pneumonia (RSV-LRI) in relation to disease severity. METHODS: One hundred seven children admitted with RSV-LRI were enrolled. The patients were divided into 2 groups according to serum IgE levels: the high IgE (n=39, more than 2 standard deviations from the mean levels for age-matched controls) and low IgE groups (n=68). We investigated if there were any differences in clinical and laboratory findings, and recurrence of wheezing between the 2 groups. The difference in IgE levels between severe (severity score≥3) and nonsevere groups was also studied. RESULTS: More frequent and prolonged fever was observed in the high IgE group than in the low IgE group (P<0.05). Patients showing severe symptoms or respiratory difficulties were more frequently seen in the high IgE group (P=0.01). There was no difference in parental allergy and atopic sensitization. The nearly same findings were observed in reanalysis of data from patients with the first RSV-LRI, but recurrence of wheezing was significantly higher in the high IgE group than in the low IgE group (P=0.04). Patients with high IgE levels were more frequently seen in severe patients than in nonsevere patients (P=0.01). CONCLUSION: Our study showed that children who presented with high serum IgE levels during RSV infections had more severe symptoms compared to those with low IgE levels. It suggests that measurement of total serum IgE levels might be helpful in evaluating disease severity and recurrent wheezing in children admitted with RSV-LRI.

Clinical significance of increased vascular endothelial growth factor, transforming growth factor-beta1, and YKL-40 in the serum of children with asthma

PURPOSE: Vascular endothelial growth factor (VEGF), transforming growth factor beta1 (TGF-beta1), and platelet derived growth factor (PDGF) are known to be involved in the pathogenesis of inflammation and remodeling in asthmatic airways. YKL-40, a chitinase-like protein, and clusterin have been reported to be biomarkers for severe asthma. We examined the serum levels of growth factors, YKL-40, and clusterin in children with acute asthma or stable asthma, and investigated their correlation with clinical findings and lung function parameters. METHODS: Forty-one children (> or =6 years of age) with asthma were enrolled, and 2 groups were defined: 23 patients admitted with acute asthma (acute asthma group) and 18 patients with stable asthma (stable asthma group). The serum levels of VEGF, TGF-beta1, PDGF-BB, YKL-40, and clusterin were measured using enzyme-linked immunosorbent assay and assessed in relation to clinical manifestations and spirometric parameters. Fifteen age-matched controls were also studied. RESULTS: The serum levels of VEGF, TGF-beta1, and YKL-40 were significantly elevated in children with acute asthma compared to controls. The serum levels of VEGF and YKL-40 were higher in the stable asthma group than in controls. The serum levels of VEGF, TGF-beta1, and YKL-40 were not different between the acute asthma and stable asthma groups. The serum VEGF levels in the acute asthma group correlated significantly with asthma severity. The serum TGF-beta1 levels in stable asthma group showed a significant inverse correlation with (FEV1) forced expiratory volume in one second and FEF(25%-75%) (forced expiratory flow between 25 and 75 percent of expired vital capacity). Serum YKL-40 had no significant relationship with clinical manifestations and spirometric parameters. CONCLUSION: Our study suggests that increased serum levels of VEGF and YKL-40 might affect asthmatic airways not only during acute exacerbation but also in stable state and that serum TGF-beta1 might be a biomarker for airway obstruction in children with asthma.