1147 Clinical Significance of Serum Total IgE Levels in Children with RSV-Associated Lower Respiratory Illness

Wednesday, 14 October 2015
Hall D1 Foyer (Floor 3) (Coex Convention Center)

Yoon Young Jang , Catholic University Hospital of Daegu, Daegu, South Korea

Hai Lee Chung, MD , Pediatrics, Catholic University Hospital of Daegu, Daegu, South Korea

Ji Hye Kim , Catholic University Hospital of Daegu, Daegu, South Korea

Hyun Seok Lee , Catholic University Hospital of Daegu, Daegu, South Korea

Chang Ho Lee , Catholic University Hospital of Daegu, Daegu, South Korea

Background: Respiratory syncytial virus (RSV) is the most common cause of lower respiratory illness (LRI) during infancy and early childhood. RSV has been reported to induce Th2 immune response with increased IgE production during acute infection. We aimed to investigate the relationship between serum total IgE levels and clinical characteristics in the children with RSV-associated LRI  (RSV-LRI).

Methods: One hundred and seven children under 3 years of age who were admitted with RSV-LRI (bronchiolitis and/or pneumonia) were enrolled. The patients were divided into 2 groups according to their total serum IgE levels on admission: High IgE group (N=39) and normal IgE group (N=68). High IgE levels were defined as values higher than 2 standard deviations (SDs) from the age-matched mean value. The medical records of the patients were investigated to determine if there was any difference in demographic characteristics, clinical and laboratory findings during admission, and recurrence of wheezing within 1 year after discharge between these 2 groups. Among 107 patients, 76 had LRIs for the first time in their lives, from whom we re-analyzed the data in relation to IgE levels. Additionally, difference between children with isolated RSV infection (N=107) and mixed infection with other viruses (N=88) was examined.

Results: Median age was 15 months in high IgE group and 5.6 months in normal IgE group (P<0.001). Male preponderance was observed only in the high IgE group (P<0.01). The frequency and duration of fever, severity of symptoms, and  concurrence of respiratory difficulty were significantly higher in high than normal IgE group (P<0.05). There was no difference in admission days and parental allergic diseases. Nearly same findings were observed in re-analysis of data from the patients with the 1st RSV-LRIs, but recurrence of wheezing after discharge was significantly higher in high IgE group (P<0.05). The children with isolated RSV infection showed more frequent and prolonged wheezing than those with mixed infection.

Conclusions: In our study, the children who presented with high serum IgE levels during RSV-LRI had more severe symptoms comparing with those with normal IgE levels. Our results suggest that increased Th2 immune response induced by acute RSV infection might be associated with severe clinical presentation of LRI.