Presentation: Exhaled Nitric Oxide in Korean Children with Allergic Rhinitis ( World Allergy Congress)

Friday, 16 October 2015

Hall D1 Foyer (Floor 3) (Coex Convention Center)

Seung Hyun Moon, MD , Department of Pediatrics, Inha University Hospital, Incheon, South Korea

Chan Yang Kim , Environmental Health Center for Allergic Rhinitis, Inha University Hospital, Incheon, South Korea

Hae Ji Jang , The Environmental Health Center for Allergic Rhinitis, Inha University Hospital, Incheon, South Korea

Yoon Sung Park , The Environmental Health Center for Allergic Rhinitis, Inha University Hospital, Incheon, South Korea

Dae Hyun Lim, MD, PhD , Environmental Health Center for Allergic Rhinitis, Inha University Hospital, Incheon, South Korea

Jeong Hee Kim, MD, PhD , Department of Pediatrics, Inha University Hospital, Incheon, Seoul, South Korea

A) Background : Fractional concentration of NO in exhaled breath (FeNO) is mainly used to evaluate the eosinophilic inflammation in asthma. It has also been proposed as an index for evaluating the atopic disease such as allergic rhinitis. Many studies suggest the usefulness of FeNO in allergic rhinitis and level of FeNO may be different depending on the race, age, and other environmental factor. But there have been few studies about the FeNO in Korean children with allergic rhinitis. The aim of this study was to investigate the usefulness of FeNO in Korean children with allergic rhinitis.

B) Methods : 647 children aged 5 to 17 were enrolled. All subjects underwent skin prick test, pulmonary function test, and methacholine challenge test. Subjects were classified into 5 groups: 139 children with allergic rhinitis(AR), 83 children with non-allergic rhinitis(NAR), 18 children with asthma, 62 children with AR and asthma, and 345 control subjects. FeNO was then measured in all subjects.

C) Results : Mean level of FeNO in AR (32.3 ± 25.0 ppb), asthma (31.1 ± 20.5 ppb), and AR-asthma group (34.5 ± 30.4 ppb) was significantly higher as compared to that of NAR (16.8 ± 13.5 ppb) and control group (15.9 ± 12.5 ppb).(P<0.05) There was no significant difference in FeNO level among AR, asthma, and AR-asthma group. There was no significant difference in FeNO level between AR group with BHR and AR group without BHR. In skin prick test, mean level of FeNO in greater than or equal to 4+ group (36.6 ± 29.2 ppb) was significantly higher than that of 3+ group (27.6 ± 20.7 ppb). (P<0.01) In the ROC curve analysis for prediction of AR, when it showed 90% of positive predictive value, the cutoff level of FeNO was 50 ppb.

D) Conclusions : Level of FeNO has a significant correlation with allergic rhinitis. This result suggests that measurement of FeNO may be useful in the diagnosis of allergic rhinitis. And also, it suggests that there is relationship between allergic rhinitis and eosinophilic inflammation like asthma, although there is no expression of systemic eosinophilic reaction or bronchial hyper reactivity.

3193 Exhaled Nitric Oxide in Korean Children with Allergic Rhinitis