The Application Of Fractional Exhaled Nitric Oxide And Fractional Nasal Nitric Oxide In The Diagnosis Of Upper And Lower Airway Inflammatory Diseases In Children

In recent years,with the change of social environment and people’s lifestyle,chronic respiratory diseases have become a major global public health problem,especially,the increasing incidence of chronic airway inflammatory diseases in children,which not only has a great impact on the quality of life of children,but also brings a great economic burden to their families and society.The study found that inflammatory diseases of the upper and lower airways are similar not only in clinical manifestations,but also in epidemiology and pathophysiology.Bronchial asthma（asthma for short）is one of the most common chronic inflammatory diseases of the lower airway in children.Its pathogenesis involves genetic,immune,endocrine factors and neural signaling pathways.As chronic airway inflammation is the main pathological basis of asthma,monitoring and evaluating airway inflammation is of great significance for the early diagnosis and accurate treatment and management of asthma.The role of fractional exhaled nitric oxide（Fe NO）in asthma has attracted increasing attention since1993,when it was found that asthma patients had elevated levels of Fe NO.Fe NO was found to be an indicator of airway type II inflammation.Fe NO detection has shown unique advantages in the diagnosis and classification of asthma,guidance of asthma treatment and prevention of acute asthma attacks.The upper and lower airways are considered to be a continuous and unified functional unit.Therefore,the concept of united airway disease gradually emerged.Allergic rhinitis and chronic rhinosinusitis,as inflammatory diseases of the upper respiratory tract,have been proved to be the most related to asthma.The coexistence of the two diseases affects the treatment and prognosis of children with asthma,and may affect the lung function of children with asthma.It has been found that the level of fractional nasal nitric oxide（Fn NO）increased in children with allergic rhinitis and decreased in children with chronic rhinosinusitis.Other studies have shown that Fe NO and Fn NO levels change more significantly when children with asthma are complicated with allergic rhinitis or chronic rhinosinusitis.Dynamic monitoring of Fn NO and Fe NO levels has important application value in helping to understand the potential pathophysiological process of children with asthma and guiding the individualized and comprehensive management of children with asthma.However,there are few studies on the detection of Fe NO combined with Fn NO in children with asthma and asthma with allergic rhinitis and chronic rhinosinusitis.Based on this,this study explored the clinical value of Fe NO combined with Fn NO detection in children with asthma and asthma complicated with allergic rhinitis and chronic rhinosinusitis,and its correlation with various indicators of lung function,and explored the diagnostic value of Fn NO detection in children with asthma complicated with allergic rhinitis and chronic rhinosinusitis.Objective:The purpose of the study was to explore the clinical value of Fe NO combined with Fn NO detection in children with asthma and asthma complicated with allergic rhinitis and chronic rhinosinusitis,and its correlation with various indicators of lung function,and explored the diagnostic value of Fn NO detection in children with asthma complicated with allergic rhinitis and chronic rhinosinusitis.Method:A total of 179 asthmatic children aged 6-14 years old who visited the outpatient and inpatient department of Pediatric Respiratory Department of our hospital from September 2020 to December 2022 were selected as the research objects.According to clinical symptoms,signs and auxiliary examination,the asthmatic children were divided into simple asthma group:56 cases,asthma combined with allergic rhinitis group:63cases,asthma combined with chronic rhinosinusitis group:60 cases.According to the clinical phenotype,chronic rhinosinusitis can be divided into those with and without nasal polyps.In this study,it was confirmed that all children with chronic rhinosinusitis were CRSs NP through sinuses CT/nasopharyngoscopy examination.Information of all enrolled children was collected,including age,gender,immunoglobulin E（Ig E）,percentage of eosinophils in peripheral blood（PEOS%）,peripheral blood eosinophil count（PEOS）,Fe NO,Fn NO,lung function indicators[forced vital capacity（FVC）,forced expiratory volume in one second（FEV₁）,peak expiratory flow（PEF）,forced expiratory flow at 75%vital capacity（FEF25）,forced expiratory flow at 50%vital capacity（FEF50）,forced expiratory flow at 25%vital capacity（FEF75）,maximummidexpiratoryflow（MMEF）,bronchodilation test（BDT）].Firstly,the differences in age,gender,Fe NO level,Fn NO level and various indicators of lung function in each group were analyzed.Secondly,the correlation between Fe NO level,Fn NO level and various indicators of lung function,Ig E,PEOS%and PEOS was analyzed,and the diagnostic value of Fn NO detection in children with asthma complicated with allergic rhinitis and chronic rhinosinusitis was explored.Result:1.There were no significant difference in age,sex composition ratio,PEOS%,PEOS and Ig E among the 3 groups（P>0.05）.2.Fe NO level of asthma combined with allergic rhinitis group was higher than that of asthma group and asthma combined with chronic rhinosinusitis group（P<0.05）.The levels of Fn NO in asthma combined with chronic rhinosinusitis group,asthma group and asthma combined with allergic rhinitis group were increased successively,and there were significant differences among groups（P<0.05）.3.There was no significant difference in pulmonary function indexes（FVC%,FEV₁%,FEV₁/FVC%,PEF%,FEF25%,FEF50%,FEF75%,MMEF%,BDT）among asthma group,asthma combined with allergic rhinitis group,and asthma combined with chronic rhinosinusitis group（P>0.05）.4.In asthma group,Fe NO level was negatively correlated with FVC%,FEV₁%,FEV₁/FVC%,FEF50%,FEF75%and MMEF%（P<0.05）,but not with PEF%,FEF25%and BDT（P>0.05）.Fe NO level in asthma combined with allergic rhinitis group and asthma combined with chronic rhinosinusitis group was negatively correlated with FVC%and FEV₁%（P<0.05）,but had no significant correlation with FEV₁/FVC%,PEF%,FEF25%,FEF50%,FEF75%,MMEF%and BDT（P>0.05）.There was no correlation between Fe NO level and Fn NO level in the 3 groups（P>0.05）,but Fe NO level was positively correlated with PEOS%,PEOS and Ig E（P<0.05）.There was no significant correlation between Fn NO level and various indicators of lung function（FVC%,FEV₁%,FEV₁/FVC%,PEF%,FEF25%,FEF50%,FEF75%,MMEF%,BDT）,PEOS%,PEOS and Ig E in the 3 groups（P>0.05）.5.The proportion of allergic rhinitis and chronic rhinosinusitis in children with asthma was 35.2%and 33.5%.Receiver operating characteristic curye（ROC）curve analysis results showed that Fn NO>441ppb,the Area Under Curve（AUC）was0.829,and the sensitivity and specificity of predicting allergic rhinitis in children with asthma were 89.0%and 51.0%.Respectively,Fn NO<151ppb,the AUC was 0.904,and the sensitivity and specificity of predicting chronic rhinosinusitis in children with asthma were 87.0%and 84.0%.Conclusion:1.The level of Fe NO is positively correlated with Ig E,PEOS%and PEOS in children with acute exacerbation of asthma,suggesting that Fe NO can be used as a marker of typeⅡinflammation.2.The level of Fn NO is significantly increased in children with asthma and allergic rhinitis,while it is significantly decreased in children with asthma and chronic rhinosinusitis.The results suggest that Fn NO may be helpful in the diagnosis of allergic rhinitis and chronic rhinosinusitis in children with asthma.3.The inflammatory response of the upper and lower airways is correlated.During clinical diagnosis and treatment,attention should be paid to the assessment of overall airway inflammation,and airway inflammation and airway function should be monitored at the same time.