Related Experiment Video
Updated: Jun 4, 2026

Noninvasive Sampling of Mucosal Lining Fluid for the Quantification of In Vivo Upper Airway Immune-mediator Levels
Published on: August 7, 2017
Exhaled nitric oxide discriminates children with and without allergic sensitization in a population-based study
1Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan. yao@adm.cgmh.org.tw
Background:
Fraction of exhaled nitric oxide (FeNO) as a biomarker of airway inflammation in children warrants better clarification.
Objective:
To identify the determinants of FeNO in children and assess the validity of FeNO as a discriminative tool for asthma, rhinitis or allergic sensitization in a population setting.
Methods:
Children aged 5-18 years (N=1717) were evaluated using online FeNO measurements, questionnaires, anthropometric measurements, pulmonary function tests and total and specific serum IgE.
Results:
FeNO levels were age-dependent, with an average increase of 7.4% per year of age. It decreased with increasing body mass index (BMI), estimated at 1.5% decrease per kg/m(2) . Children with allergic sensitization had elevated FeNO independent of allergic symptoms. In the combined analyses of asthma, rhinitis and allergic sensitization, elevated FeNO levels were confined mainly to children having allergic sensitization. After adjusting for allergic sensitization, a significant association between rhinitis and FeNO remained, but no such association was seen with asthma. The sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) of FeNO at the optimum cut-off of 28 p.p.b. for diagnosing asthma were 64.3%, 69.9%, 8.8%, and 97.7%, respectively (area under the ROC curve [AUC] 0.67), and were slightly better for diagnosing allergic asthma: 70.0%, 70.4%, 9.0%, 98.3%, respectively (AUC 0.71). FeNO had modest accuracy in discriminating rhinitis with an AUC value of 0.70, and performed better in discriminating allergic rhinitis (AUC 0.78). FeNO was a robust discriminator of allergic sensitization independent of symptoms at a cut-off of 15.4 p.p.b. (AUC 0.80; sensitivity 72.2%; specificity 71.2%; PPV 76.9%; NPV 65.8%).
Conclusion And Clinical Relevance:
FeNO measurement discriminates children with and without allergic sensitization independent of allergic symptoms. On the other hand, low FeNO levels in children may help exclude allergic asthma but high levels may be caused by allergic sensitization, older age, rhinitis, and lower BMI, in addition to asthma.
More Related Videos
08:23Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
05:46A Novel Inhalation Mask System to Deliver High Concentrations of Nitric Oxide Gas in Spontaneously Breathing Subjects
Published on: May 4, 2021
Related Concept Videos
Asthma I: Introduction
Asthma-II: Pathophysiology and Classification
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:
Asthma-IV: Diagnostic and Management
Clinical Assessment for Asthma:
This is the first step in diagnosing and managing asthma. It includes:
Asthma III: Clinical Manifestations
Sputum Studies II: Culture and Sensitivity
Sputum culture and sensitivity is a medical procedure used to diagnose bacterial infections in the respiratory tract and select the most appropriate antibiotics for treatment. This process involves analyzing sputum samples of thick and opaque secretions produced in the lungs and airways. These samples are collected from patients and then sent to the laboratory for analysis.
The test can identify various pathogens responsible for respiratory infections, including Streptococcus,...