Nasal nitric oxide in upper airways in children with asthma and allergic rhinitis

Application of fractional exhaled nitric oxide and nasal nitric oxide in control evaluation of bronchial asthma and diagnosis of allergic rhinitis in children

OBJECTIVES

To study the association of fractional exhaled nitric oxide (FeNO) and nasal nitric oxide (nNO) with asthma control and their value in the diagnosis of allergic rhinitis in children.

METHODS

A total of 186 children aged 5-12 years, who attended the outpatient service of the Department of Respiration, Shanghai Children's Hospital due to bronchial asthma and/or allergic rhinitis or who underwent physical examination, were enrolled as subjects, with 52 children in the asthma group, 60 children in the asthma+allergic rhinitis group, 36 children in the allergic rhinitis group, and 38 children in the control group. FeNO, nNO, and pulmonary function were compared between groups.

RESULTS

The asthma+allergic rhinitis, asthma, and allergic rhinitis groups had a significantly higher level of FeNO than the control group (P<0.05). The asthma+allergic rhinitis and allergic rhinitis groups had a significantly higher level of nNO than the asthma and control groups (P<0.05). The uncontrolled asthma and partially controlled asthma groups had significantly higher levels of FeNO and nNO than the completely controlled asthma group (P<0.05). The receiver operating characteristic (ROC) curve analysis showed that nNO had an area under the ROC curve of 0.91, with a sensitivity of 80.0% and a specificity of 89.5% in the diagnosis of allergic rhinitis in children with asthma (P<0.05).

CONCLUSIONS

The combined measurement of nNO and FeNO can be used to evaluate the control of asthma, and the measurement of nNO can help with the diagnosis of allergic rhinitis in children with bronchial asthma.

The Role of Nasal Nitric Oxide and Anterior Active Rhinomanometry in the Diagnosis of Allergic Rhinitis and Asthma: A Message for Pediatric Clinical Practice

Background

Allergic rhinitis (AR) and asthma are two common atopic diseases, often associated with a common ethiopathogenesis characterized by a Th2 inflammatory response with the release of many biomarkers, such as nitric oxide (NO).

Purpose

To evaluate and compare inflammatory (nFeNO and eFeNO) and functional (mNF and FEV1) parameters in AR children with or without asthma in comparison to controls. Secondly, we aimed to identify nFeNO cut-off values and verify their reliability to predict the presence of rhinitis or asthma alone or in combination.

Patients and Methods

We enrolled 160 children (6-12 years of age) with AR and/or asthma divided into four groups: controls, AR, asthma, and AR + asthma. All children underwent the following inflammatory and functional measurements: nFeNO, eFeNO, mNF and FEV1.

Results

We observed that levels of nFeNO were extremely higher in children with AR and even more in those with AR + asthma in respect to controls. Notably, all the pathological conditions, especially AR + asthma, showed significantly lower values of mNF compared to healthy children. A negative correlation linked mNF and nFeNO. Then, we found eFeNO values significantly higher in all the pathological groups compared to controls, with major values of this marker in patients affected by asthma and AR + asthma, as well as FEV1 values significantly lower in all the disease groups, especially in children with asthma and AR+ asthma. ROC curve analysis showed that nFeNO was a great predictor for rhinitis alone or with asthma, revealing an accurate cut-off of 662 ppb.

Conclusion

nFeNO measurement is non-invasive, easy to perform, economic and a valuable test in case of AR alone or in association with asthma. Thus, it should be used in patients with rhinitis, together with anterior active rhinomanometry (AAR) to diagnose and estimate the degree of nasal obstruction but also in children with asthma to assess their nasal involvement and improve the therapeutic management.

Clinical application of nasal nitric oxide measurement in allergic rhinitis: A systematic review and meta-analysis

BACKGROUND

Nasal nitric oxide (nNO) is considered a biomarker of nasal inflammation.

OBJECTIVE

To perform a systematic review with meta-analysis and meta-regressions on the association between nNO levels and allergic rhinitis (AR).

METHODS

PubMed, Web of Science, Scopus, and EMBASE databases were systematically searched. Differences between cases and controls were expressed as standardized mean differences (SMD) with 95% confidence intervals (CI).

RESULTS

Overall, 39 articles were included: 30 containing data on nNO measured by nasal aspiration (1881 patients with AR and 1337 controls) and 12 assessing nNO by nasal exhalation (525 patients with AR and 350 controls). Compared with controls, AR presented significantly higher nNO values both during nasal aspiration (SMD, 1.309; 95% CI, 0.841-1.777; P < .001) and nasal exhalation (SMD, 0.708; 95% CI, 0.303-1.114; P = .001). Sensitivity and subgroup analyses confirmed that the results for the evaluated outcomes were not affected by the presence of clinical confounding factors (asthma, nasal polyps, inhaled corticosteroids, smoking history), this being valid for both perennial and seasonal diseases during exposure to allergens. For the aspiration method, meta-regressions indicated that older age and a better pulmonary function were associated with a lower difference in nNO levels between patients with AR and controls, whereas an increasing aspiration flow was associated with a high effect size.

CONCLUSION

nNO levels are higher in AR, particularly when using high aspiration flows and in younger patients, who often perceive this condition as a source of disability. Further studies are needed to evaluate the usefulness of this biomarker for monitoring airway disorders and optimizing strategies in different settings (community, hospital, rehabilitation).

Pragmatic Markers in the Management of Asthma: A Real-World-Based Approach

Bronchial hyperreactivity, reversible airflow limitation and chronic airway inflammation characterize asthma pathophysiology. Personalized medicine, i.e., a tailored management approach, is appropriate for asthma management and is based on the identification of peculiar phenotypes and endotypes. Biomarkers are necessary for defining phenotypes and endotypes. Several biomarkers have been described in asthma, but most of them are experimental and/or not commonly available. The current paper will, therefore, present pragmatic biomarkers useful for asthma management that are available in daily clinical practice. In this regard, eosinophil assessment and serum allergen-specific IgE assay are the most reliable biomarkers. Lung function, mainly concerning forced expiratory flow at 25-755 of vital capacity (FEF_25-75), and nasal cytology may be envisaged as ancillary biomarkers in asthma management. In conclusion, biomarkers have clinical relevance in asthma concerning both the endotype definition and the personalization of the therapy.