Effects of Ionized Waterfall Aerosol on Pediatric Allergic Asthma

Objective. Ionized water aerosols have been suggested to exert beneficial health effects on pediatric allergic asthma. Their effect was evaluated in a randomized controlled clinical trial as part of a summer asthma camp. Methods. Asthmatic allergic children (n = 54) spent 3 weeks in an alpine asthma camp; half of the group was exposed to water aerosol of an alpine waterfall for 1 hour per day, whereas the other half spent the same time at a “control site”. Immunological analysis, lung function testing, and fractional exhaled nitric oxide (FeNO) testing were performed during the stay, and sustaining effects were evaluated 2 months later. Symptom score testing was done over a period of 140 days. Results. The water aerosol group showed a significant improvement in all lung function parameters, whereas only the peak expiratory flow improved in the control group. All patients showed a significant improvement in symptom score and a significant decrease in FeNO after the camp. Only the water aerosol group exhibited a long-lasting effect on asthma symptoms, lung function, and inflammation in the follow-up examination. Induction of interleukin (IL)-10 and regulatory T (Treg) cells was measured in both groups, with a pronounced increase in the water aerosol group. IL-13 was significantly decreased in both groups, whereas IL-5 and eosinophil cationic protein were decreased only in the water aerosol group. Conclusions. Our findings confirm the induction of Treg cells and reduction in inflammation by climate therapy. They indicate a synergistic effect of water aerosols resulting in a long-lasting beneficial effect on asthma symptoms, lung function, and airway inflammation.     

Exhaled Nitric Oxide Decreases in Association with Attendance at an Asthma Summer Camp

Attendance at a summer asthma camp has been associated with improved outcomes in children with asthma. We hypothesized that one mechanism involved in improved asthma outcomes is reduction in airway inflammation. To investigate this, we measured the fractional concentration of exhaled nitric oxide (FeNO), lung function (forced expiratory volume in 1 sec, FEV₁) and asthma control (Juniper Asthma Control Questionnaire, ACQ) from children at the beginning and end of a 1-week asthma summer camp. We also obtained a symptoms-only ACQ at 1 and 6 months after the end of camp. We enrolled 10 girls, 17 boys, mean (± SD) age = 9.6 ± 1.3 years. At baseline, FeNO (ppb), median (25–75 IQR) = 11.4 (7.2–21.3); ACQ = 0.86 (0.43–1.21); FEV₁ (%pred, mean ± SD) = 87 ± 10. At the end of camp, FeNO = 6.2 (4.4–8.4), a change of ?45%, p < 0.0001; ACQ = 0.71 (0.43–1.14), a fall of 14%, p = 0.72; and mean FEV₁% predicted remained unchanged. There were no significant changes in the follow-up symptoms-only ACQ at 1 and 6 months. We conclude that airway inflammation, as measured by FeNO, improved during 1 week of asthma camp, but there were no significant changes in lung function or asthma control. Since no child had a change in anti-inflammatory therapy during camp, these findings suggest that airway inflammation was reduced because of improved adherence to therapy and/or reduced exposure to pro-inflammatory stimuli in the home environment. The finding of reduced inflammation following attendance at an asthma summer camp should motivate the child, the parents and the clinician to focus their efforts on improving adherence to therapy and reducing exposures at home.     

Exhaled Nitric Oxide in Children with Allergic Rhinitis and/or Asthma: A Relationship with Bronchial Hyperreactivity

Background. Nowadays, the measure of the fractional concentration of exhaled nitric oxide (FeNO) enables to assess airway inflammation during an office visit and there is international consensus on this testing methodology. The aim of this study was to evaluate whether FeNO measurement is predictable for bronchial hyperreactivity (BHR) in children with allergic rhinitis, asthma, or both. Methods. Two hundred and eighty children with allergic rhinitis, allergic asthma, or both were evaluated. Bronchial function (FEV₁ and FEF_25–75), BHR (assessed by methacholine challenge), FeNO, and sensitizations were assessed. Results. Bronchial function, BHR, and FeNO were significantly different in the three groups (p < .001). A strong inverse correlation between FeNO and BHR was found in patients with asthma and with asthma and rhinitis (r?=??0.63 and r?=??0.61, respectively). A cutoff of 32 ppb of FeNO was a predictive factor for BHR. Conclusions. This study highlights the relevance of FeNO as possible marker for BHR in allergic children and underlines the close link between upper and lower airways.     

未控制支气管哮喘患者痰嗜酸粒细胞水平与肺功能相关性分析

目的:分析未控制支气管哮喘(哮喘)患者不同水平痰嗜酸粒细胞的临床特点,探讨未控制哮喘患者痰嗜酸粒细胞与肺功能的相关性。方法:纳入2017年8月至2019年9月就诊于内蒙古自治区人民医院呼吸与危重症医学科的未控制哮喘患者167例病例资料进行回顾性研究,根据诱导痰嗜酸粒细胞百分比结果将患者分为2组,以痰嗜酸粒细胞百分比≥2...     

呼出气一氧化氮在哮喘中的临床意义

目的哮喘以慢性气道炎性反应为特征,主要涉及嗜酸性粒细胞的募集和活化。呼出气一氧化氮(fractional exhaled nitric oxide, FeNO)是气道炎症的一个非侵入性标志物。本文探讨了FeNO在哮喘中的临床意义。 方法我们评估了94例哮喘患者治疗前后的FeNO和肺功能参数及哮喘控制检测(asthma control test, ACT)评分,其中完成1个月随访的有75例,完成3个月随访的有73例,分析了我院哮喘患者控制水平的一些相关因素。 结果发现诊断时的FEV1%在预测哮喘控制时最具优势,哮喘患者根据ACT评分划分的不同控制状态的FeNO和肺功能参数无明显差异。FeNO和肺功能参数,ACT评分及血IgE,血嗜酸性粒细胞计数之间无明显相关性。FEV1%与ACT评分之前存在正相关(r＝0.04184,P＝0.0492)。无过敏性鼻炎(allergic rhinitis, AR)组,FeNO和ACT评分之间存在负相关(r＝0.2015,P＝0.0128)。3个月治疗后FeNO和ACT评分之间仍无明显相关性。 结论哮喘患者治疗前后的FeNO可以评估患者的治疗效果,而FeNO并不能预测哮喘的控制状态及恶化风险,FEV1%在预测哮喘控制方面具有临床意义。     

Exhaled nitric oxide in the management of childhood asthma: a prospective 6-months study

Fractional exhaled nitric oxide (FeNO) is elevated in asthma and reflects eosinophilic airway inflammation. The aim of this prospective, randomized, single-blind study was to examine whether the inclusion of repeated FeNO measurements into asthma monitoring leads to an improvement in asthma outcome. Forty-seven children with mild to moderate asthma were allocated to a FeNO group (n = 22) and to a control group (n = 25). In the FeNO group therapy was based on symptoms, beta-agonist use, lung function, and FeNO whereas in the control group therapy was based on symptoms, beta-agonist use and lung function only. Patients performed five visits in 6 weeks intervals. Frequency of respiratory symptoms, beta-agonist use, FEV(1)% predicted and the frequency of exacerbations were similar between groups. Patients in the FeNO group received higher doses of inhaled corticosteroids (ICS) (control group: median (interquartile range): 241 microg (26-607 microg); FeNo group: 316 microg (200-500 microg) and had significantly higher MEF(50)% predicted (control group: median (interquartile range): 68.5% (55.8-83.1%); FeNO group: 83.2% (62.9%-98.3%). At a cut-off point of 22.9 ppb FeNO the best predictive value for exacerbations with a sensitivity of 80% and specificity of 60% was found. Significant relationships were observed between FeNO and dose of ICS (beta = -8.77; P < 0.002), beta-agonist use 2 weeks prior to a visit (beta = 0.11; P < 0.05), asthma symptoms (beta = 0.02; P < 0.0001), and bronchial hyperresponsiveness (beta = 0.04; P = 0.02). In conclusion, FeNO was related to important markers of asthma control. A therapy regimen aimed at lowering FeNO in children with asthma improved parameters of small airway function, but was not able to improve clinical markers of asthma control.     

The effect of montelukast on lung function and exhaled nitric oxide in infants with early childhood asthma.

Effective treatment of respiratory symptoms, airway inflammation and impairment of lung function is the goal of any asthma therapy. Although montelukast has been shown to be a possible add-on therapy for anti-inflammatory treatment in older children, its efficacy in infants and young children is not well known. The aim of this study was to investigate its effect in infants and young children with early childhood asthma. In a prospective randomised double-blind placebo-controlled study, 24 young children (10-26 months) with wheeze, allergy and a positive family history of asthma consistent with the diagnosis of early childhood asthma were randomised to receive montelukast 4 mg or placebo. The forced expiratory volume in 0.5 seconds (FEV0.5) was measured using the raised volume rapid thoracic compression technique, and fractional exhaled nitric oxide (FeNO) and symptom scores were determined. No change was noted in FEV0.5, FeNO or symptom score in the placebo group following the treatment period. In contrast, significant improvements in mean+/-SD FEV0.5 (189.0+/-37.8 and 214.4+/-44.9 mL before and after treatment, respectively), FeNO (29.8+/-10.0 and 19.0+/-8.5 ppb) and median symptom score (5.5 and 1.5) were noted following treatment with montelukast. In conclusion, montelukast has a positive effect on lung function, airway inflammation and symptom scores in very young children with early childhood asthma.     

呼出气一氧化氮对支气管哮喘的诊断价值及其与气道炎症的相关性分析

目的 通过探讨呼出气一氧化氮(FeNO)与肺泡灌洗液中气道炎症细胞、肺功能、血清总IgE及支气管激发试验的相关性,明确FeNO对哮喘的诊断价值,并寻求适用于哮喘患者气道炎症监测、评估与管理的方法.方法 选择符合标准的哮喘患者103例及健康对照组49例,对其分别进行FeNO及支气管激发试验.同时哮喘患者行BALF检查;同时进行肺功能,记录FEV1％pred、FEV1/FVC、最大呼气中期流速(MMFR)、呼气峰流速(PEF);行血常规、血清总IgE检查.结果 将FeNO的影响因素引入多重线性回归分析,发现FeNO主要受年龄、过敏性鼻炎、吸烟指数的影响,与肺泡灌洗液中嗜酸粒细胞百分比(EOS％)呈显著正相关(r =0.278,P=0.007).外周血EOS％增高,FeNO值增加,但外周血EOS％在不同FeNO水平间的差异无统计学意义(F=2.868,P=0.062);血清总IgE随FeNO增加显著,且其在不同FeNO水平间的差异有统计学意义(F=4.407,P=0.015).ROC曲线示PC20的曲线下面积AUC:0.853,95％ CI:0.778～0.928,FeNO曲线下面积AUC:0.712,95％ CI:0.628～0.796.PC20≤8 g/L为阳性判断标准时的灵敏度(0.837vs 0.674)以及特异度(0.776 vs 0.571)均高于以FeNO浓度≥26.5 ppb的阳性阈值.结论 FeNO与肺泡灌洗液EOS及血清总IgE关系密切,在评估哮喘患者嗜酸性气道炎症中具有重要作用;与支气管激发试验相比,FeNO在诊断哮喘上的灵敏度和特异度相对较低,因此在哮喘的诊断上FeNO检测不能完全替代支气管激发试验.     

离线FeNO及潮气肺功能量化指标在<5岁儿童哮喘管理中的应用研究

目的探讨离线呼出气一氧化氮(FeNO)及潮气肺功能联合监测对年幼儿童哮喘控制的价值。方法回顾性研究。选取2017年10月至2019年10月于成都市妇女儿童中心医院哮喘门诊初次确诊的哮喘患儿81例,年龄范围为10~55个月(<5岁),其中男58例,女23例。选择同期儿童保健门诊非喘息健康体检儿童65名为对照组。比较2组血嗜酸粒细胞、总IgE、过敏原阳性率、离线FeNO及潮气肺功能的差异。哮喘组给予抗哮喘治疗3个月、6个月后,复查离线FeNO及潮气肺功能,比较两指标治疗前后的变化。结果(1)哮喘组患儿离线FeNO、过敏原阳性率均高于对照组,达峰时间比(TPTEF/TE)、达峰容积比(VPEF/VE)均低于对照组,差异均有统计学意义(P值均<0.05)。(2)哮喘组治疗3个月随访肺功能TPTEF/TE、VPEF/VE与初期比较明显好转,差异均有统计学意义(P值均<0.05);离线FeNO变化不明显,差异无统计学意义(P>0.05)。治疗6个月随访,与治疗初期比较,离线FeNO明显下降,差异有统计学意义(P<0.05)。结论离线FeNO及潮气肺功能可作为<5岁哮喘儿童管理的量化指标。抗哮喘治疗后FeNO的改变滞后于肺功能的改善,FeNO及肺功能联合运用,更利于<5岁儿童哮喘的精准管理。     

Effects of montelukast on subjective and objective outcome measures in preschool asthmatic children

It is well accepted that control of airway inflammation is crucial for overall asthma control. Hence, efficient anti-inflammatory therapy is important for disease control. Therefore, we studied the effect of a treatment with montelukast on subjective and objective measures in preschool asthmatic children with insufficient control of airway inflammation, illustrated by increased fractional exhaled nitric oxide (FeNO). Thirty-one preschool children (2.5-5 years) were included in this study. Children with FeNO > or = 10 ppb at the first visit received montelukast 4 mg as a first line therapy or an add-on therapy to their baseline treatment (group 1). Therapy was not changed at first visit in children with FeNO < 10 ppb (group 2). Symptom scores, FeNO, lung function (forced oscillation, Rrs8Hz) and airway responsiveness to adenosine 5'-monophosphate (AMP) were assessed at visits 1 and 2 eight weeks apart. There was a significant decrease in FeNO (median [interquartile range]; 12.9 [3.7] vs. 7.6 [6.85] ppb, P = 0.011), Rrs8Hz (mean +/- SD; 10.03 +/- 3.1 vs. 8.72 +/- 2.43 hPa.s/L; P = 0.047) and symptom scores (2[2] vs. 1.5[2], P = 0.034) and a significant increase in the provocative AMP dose (2.65 +/- 2.1 vs. 4.54 +/- 1.05; P = 0.015) in group 1 but not in group 2. First line or add-on treatment of oral montelukast in preschool children with mild to moderate asthma and elevated FeNO, decreased levels of FeNO, improved airway responsiveness to AMP, lung function and symptom scores.     

Phenotype classification using the combination of lung sound analysis and fractional exhaled nitric oxide for evaluating asthma treatment

Background

We report the utility of combining lung sound analysis and fractional exhaled nitric oxide (FeNO) for phenotype classification of airway inflammation in patients with bronchial asthma.We investigated the usefulness of the combination of the expiration-to-inspiration sound power ratio in the mid-frequency range (E/I MF) of 200–400 Hz and FeNO for comprehensively classifying disease type and evaluating asthma treatment.

Obesity,sedentary lifestyle,and exhaled nitric oxide in an early adolescent cohort

Fractional exhaled nitric oxide (FeNO) is a marker of airway inflammation that is well‐characterized in allergic disease states. However, FeNO is also involved in nonallergic inflammatory and pulmonary vascular mechanisms or responses to environmental stimuli. We sought to determine the extent to which obesity or sedentary lifestyle is associated with FeNO in adolescents not selected on the basis of allergic disease. In Project Viva, a prebirth cohort study, we measured body mass index (BMI), skinfold thicknesses, waist circumference, body fat, hours watching television, hours of physical activity, and heart rate after exercise among 929 adolescents (median age, 12.9). We measured FeNO twice and averaged these as a continuous, log‐transformed outcome. We performed linear regression models, adjusted for child age, sex, height, and race/ethnicity, maternal education and smoking during pregnancy, household income and smoking, and neighbourhood characteristics. In secondary analysis, we additionally adjusted for asthma. More than 2 hours spent watching TV was associated with 10% lower FeNO (95% confidence interval [CI]: ?20, 0%). Higher body fat percentage was also associated with lower FeNO. After additional adjustment for asthma, teens who are underweight (BMI <5th %tile, 3%) had 22% lower FeNO (95%CI: ?40, 2%) and teens who are overweight (BMI ≥85th %ile, 28%) had 13% lower FeNO (95%CI: ?23, ?2%). Each of these associations of lifestyle and body weight with lower FeNO were greater in magnitude after adjusting for asthma. In summary, sedentary lifestyle, high and low BMI were all associated with lower FeNO in this adolescent cohort.     

过敏性鼻炎与支气管哮喘患者的Fe NO比较研究

目的探讨呼出气一氧化氮(Fe NO)在支气管哮喘(BA)和过敏性鼻炎(AR)患者中的应用,比较Fe NO和外周血嗜酸粒细胞分类(EOS%)在健康对照组(A组)、AR(B组)、BA/AR(C组)及BA(D组)之间的不同,寻找两种疾病Fe NO、EOS%改变的意义,以及两种疾病之间的关系。方法采用按国际技术标准设计的尚沃纳库仑一氧化氮分析仪对A、B、C、D组患者检测Fe NO,同时测定各组患者血常规。结果三组病例ROC曲线下面积均大于0.5;AR、BA/AR、BA三组Fe NO、EOS%水平均高于对照组(P0.05),三组组间无明显差异(P0.05);Fe NO与EOS%间存在显著相关性(r=0.505,P0.0 5)。结论Fe NO诊断支气管哮喘和过敏性鼻炎有临床意义。Fe NO可以反映患者气道嗜酸性炎症水平。过敏性鼻炎与支气管哮喘这两种疾病存在密切的关系。     

The use of exhaled nitric oxide monitoring in primary care asthma clinics: a pilot study.

AIM: Although asthma is defined as a chronic inflammatory disease, inflammation is rarely assessed. The fraction of exhaled nitric oxide (FeNO) is a biomarker of airways inflammation. We assessed the feasibility of FeNO monitoring in general practice. METHODS: Prospective observational study of volunteers attending primary care asthma clinics. Consenting subjects were seen at their own surgery for 2-weekly reviews over 12 weeks, with assessment of FeNO, lung function, symptoms and health status. RESULTS: 22 adults and 15 children provided informed consent. Two subjects were unable to perform the FeNO expiratory manoeuvre. In the remaining subjects, measurements conforming to highest ERS/ATS recommendations were made on 211 of 236 occasions, and on 21 further occasions acceptable readings were made. Acceptability was high to subjects and staff. Correlations between FeNO readings and other parameters were weak and non-significant except for statistically significant correlation between longitudinal FeNO changes and changes in lung function (r= -0.33, p<0.001) and health status (r= -0.22, p=0.022). CONCLUSIONS: Exhaled nitric oxide monitoring is technically feasible and acceptable to staff and patients within the context of a primary care asthma clinic.     

Asthma diagnosis and severity monitoring in primary school children: Essential role of sequential testing of exhaled nitric oxide

BackgroundChronic eosinophilic airway inflammation, airflow limitation, and airway hyper-responsiveness are the mainstays of asthma diagnosis. The increased levels of exhaled nitric oxide (FeNO) in asthma are closely related to the extent of airway inflammation. Sequential measurement of FeNO concentrations may accurately predict asthma severity and guide therapeutic decisions.MethodsA total of 22,083 grade 1 students in Taipei city primary schools were screened for wheezing episodes using the International Study of Asthma and Allergies in Childhood questionnaire (ISAAC) questionnaires while their sero-atopic conditions were confirmed by Fluorescent Enzyme Immune Assay (FEIA). All students with allergies were tested by FeNO electrochemical test. 100 age-matched healthy students were used as control group (FeNO levels < 25 ppb).ResultsFrom the 2650 students (12%) initially included via the wheezing criteria, 2065 (78.0%) were confirmed to have allergy by FEIA (sensitisation to at least two common aero-allergens in Taiwan) and diagnosed by a paediatric allergologist. Among them, 1852 (89.6%) had elevated FeNO values (>25 ppb) and 266 (10%) had FeNO values < 25 ppb. Using the GINA guidelines, 140 mild-to-moderate asthma students who had received inhaled corticosteroids (ICS) with or without Singulair treatment completed serial FeNO testing every three months for one year. The FeNO levels decreased in 121 students (86.4%) and increased in 19 students (13.6%), which was compatible to changing childhood asthma control score and response to step-down treatment, respectively.ConclusionFeNO is an easy, used non-invasive tool for the diagnosis of allergic asthma. Sequential FeNO testing can accurately reflect asthma severity and provide for successful stepwise therapy for asthmatic children.     

Adiposity,Adipokines, and Exhaled Nitric Oxide in Healthy Adults Without Asthma

Background. Epidemiological studies have shown that obesity/adiposity is closely associated with asthma in terms of development, severity, and control of asthma. However, effects of obesity/adiposity on airway inflammation are not well known in subjects without asthma. We assessed whether fractional exhaled nitric oxide (FeNO), a marker of eosinophilic airway inflammation, was associated with obesity/adiposity in nonasthmatic healthy adults. Methods. We measured FeNO and serum levels of adipose-derived hormones and adipokines in 117 adult subjects without a previous diagnosis of asthma or current asthmatic symptoms. Associations between FeNO and measures of obesity/adiposity [body mass index (BMI), body fat mass, and body fat percentages] were examined by correlation analyses and uni- and multivariate linear regression analyses. Results. FeNO was not significantly associated with BMI, body fat mass, or body fat percentage by a multivariate linear regression model, adjusting for age, gender, chronic rhinitis, atopy, and lung function. No significant association of FeNO with serum levels of leptin, adiponectin, tumor necrosis factor (TNF)-α, or interleukin (IL)-6 was observed. Conclusions. These findings suggest that in healthy subjects without asthma, obesity/adiposity has no significant effect on eosinophilic airway inflammation and that hormones and systemic inflammation derived from adipose tissue do not affect eosinophilic airway inflammation.     

Relationship between upper airway diseases,exhaled nitric oxide,and bronchial hyperresponsiveness to methacholine

Objective: The “united airway disease” concept is based on the bidirectional interaction between asthma and rhinitis. The aim of this study was to determine the relationship between upper airway diseases and bronchial hyperresponsiveness (BHR), as well as their association with the fractional concentration of exhaled nitric oxide (FeNO) and atopy in patients with persistent symptoms suggestive of asthma requiring methacholine challenge testing (MCT) to confirm asthma diagnosis. Methods: A cross-sectional prospective study was carried out in adult patients with persistent asthma-like symptoms and negative bronchodilator testing. FeNO and MCT were performed in all patients. Asthma was confirmed based on the presence of suggestive symptoms and MCT results. Associated upper airway diseases included allergic rhinitis, nonallergic rhinitis, chronic rhinosinusitis with nasal polyps (CRSwNP), and aspirin-exacerbated respiratory disease (AERD). Results: The study included 575 patients; asthma was confirmed in 32.3%, and FeNO values ≥ 50 ppb were found in 27% of the patients. Elevated FeNO was significantly associated to AERD. The prevalence of atopy in asthma patients was 86.6%. Atopy was present in 90.4% of patients with asthma and FeNO levels ≥ 50 ppb. A significant association was found between AERD, asthma, and FeNO ≥ 50 ppb. Conclusions: Patients with symptoms suggestive of asthma but negative bronchodilator testing are commonly seen in usual practice. In this population, the association of high FeNO levels and BHR to atopy, as well as to AERD, suggests the presence eosinophilic inflammation in both the upper and lower airways and supports the “one airway” hypothesis.     

呼出气一氧化氮浓度测定对变应性鼻炎合并下气道高反应性或哮喘的预测及辅助诊断价值研究

目的 探讨呼出气一氧化氮浓度(FeNO)测定对变应性鼻炎合并无症状的下气道高反应性患者或非急性发作期(慢性持续性)哮喘患者的预测及诊断价值。方法 对广州医科大学附属第一医院呼吸科收治的20例变应性鼻炎患者、15例变应性鼻炎合并无症状的下气道高反应性患者及20例变应性鼻炎合并非急性发作期(慢性持续性)哮喘患者(年龄18～50岁)进行FeNO测定、鼻腔灌洗细胞分类计数、诱导痰细胞分类计数以及乙酰甲胆碱支气管激发试验,分析各项指标的分布特点及相关性,探讨FeNO测定对变应性鼻炎患者合并无症状支气管高反应性(BHR)或非急性发作期(慢性持续性)哮喘的预测及下气道炎症的评估。结果 FeNO值的中位数和四分位间距在单纯变应性鼻炎组、变应性鼻炎合并无症状下气道反应性增高组、以及鼻炎合并哮喘组分别为24.0(15.5,35.5)pg/L、46.5(35.0,63.0)pg/L和61.5(39.0,75.0)pg/L,3组间差异具有统计学意义(P<0.01)。以测定的FeNO值为标准对变应性鼻炎患者下气道高反应性进行判断,绘制ROC曲线(AUC=0.842,P=0.002),以34.0 pg/L为截断点则敏感度为75.0%,特异度为73.7%。以FeNO值对变应性鼻炎合并哮喘诊断的ROC曲线(AUC=0.887,P=0.000),FeNO值取41.0 pg/L时对变应性鼻炎合并哮喘诊断的敏感度为75.0%,特异度为83.1%。诱导痰中嗜酸性粒细胞(EOS)在单纯变应性鼻炎组、变应性鼻炎合并无症状下气道反应性增高组以及鼻炎合并哮喘组分别为(2.43±3.56)%、(7.36±4.98)%及(18.5%±11.26)%,3组间差异具有统计学意义(P<0.01)。结论 变应性鼻炎患者可伴有一定程度的下气道炎症,且与下气道高反应性密切相关。FeNO测定简便、稳定,对变应性鼻炎患者合并下气道高反应性或哮喘具有良好的预测和辅助诊断作用。     

Exhaled nitric oxide daily evaluation is effective in monitoring exposure to relevant allergens in asthmatic children

BACKGROUND: Though asthma is an airway inflammatory disease, the assessment of treatment efficacy is mainly based on symptom monitoring and the evaluation of lung function parameters. This study was aimed to evaluate the feasibility of exhaled nitric oxide monitoring in allergic asthmatic children who were exposed to relevant allergens in their homes. METHODS: Twenty-two children allergic to mites underwent twice-daily fractional exhaled nitric oxide (FeNO) therapy using a portable device (NIOX MINO; Aerocrine AB; Stockholm, Sweden) and peak expiratory flow (PEF) measurements before, during, and after periods of natural exposure to mite allergens. The children were admitted to the study if they had lived in a mite-free environment for 3 months. They were observed in this environment for 10 days and then were moved to a site with natural mite exposure at sea level for 19 days. Finally, they were relocated to the mite-free environment for a period of 6 days for follow-up measurements. RESULTS: Significant differences were seen between the mite-free baseline FeNO level (26.4 parts per billion [ppb]; range, 19.3 to 36.2 ppb) and FeNO levels measured during natural mite exposure (37.3 ppb; 27.3 to 51 ppb) and after natural mite exposure (34.9 natural mite exposure; 25.2 to 48.2 ppb). Six children reported asthma symptoms during the mite exposure, and an increase in FeNO was observed in each case (p<0.031); PEF values showed no significant differences, whether between the different environments or between different periods. CONCLUSIONS: These data give further evidence for a possible role of frequent determinations of FeNO in order to promptly assess changes in the level of airway inflammation in asthmatic children.     

Exhaled NO among inner-city children in New York City

Background. Fractional exhaled nitric oxide (FeNO) has been proposed as a biomarker of airway inflammation for cohort studies of asthma. Objectives. To assess the association between FeNO and asthma symptoms among 7-year-old children living in an inner-city community. To test the association between environmental tobacco smoke (ETS) exposure (previous and current) and FeNO among these children. Methods. As part of a longitudinal study of asthma, children recruited in Head Start centers at age 4 had offline FeNO and lung function testing at age 7. Children with allergen-specific immunoglobulin E (IgE) (≥0.35 IU/mL) at age 7 were considered seroatopic. ETS exposure at ages 4 and 7 was assessed by questionnaire. Results. Of 144 participating children, 89 had complete questionnaire data and achieved valid FeNO and lung function tests. Children with reported wheeze in the previous 12 months (n = 19) had higher FeNO than those without wheeze (n = 70) (geometric means 17.0 vs. 11.0 ppb, p = .005). FeNO remained significantly associated with wheeze (p = .031), after adjusting for seroatopy and forced expiratory volume in 1 second (FEV₁) in multivariable regression. FeNO at age 7 was positively associated with domestic ETS exposure at age 4 (29%) (β = 0.36, p = .015) but inversely associated with ETS exposure at age 7 (16%) (β = ?0.74, p < .001). Conclusions. Given its association with current wheeze, independent of seroatopy and lung function, FeNO provides a relevant outcome measure for studies in inner-city communities. While compelling, the positive association between ETS exposure at age 4 and a marker of airway inflammation at age 7 should be confirmed in a larger study.