Exhaled nitric oxide: relation to sensitization and respiratory symptoms (original) (raw)
Related papers
Lung India, 2014
standardized for supporting the diagnosis in cases of eosinophilic inflammation of airways, bronchial hyperreactivity and asthma. FE NO levels have been higher in atopic than non-atopic bronchial asthma patients and some studies also reported that healthy atopic subjects without symptoms or signs of airway disorders have higher FE NO levels than non-atopic subjects. Similarly the effect of clinical atopy, with atopic cases having higher levels as compared to non-atopic cases. To the best of our knowledge, the literature on exhaled breath and nasal nitric oxide from India is lacking. Hence, this study was undertaken to answer the question about the relationship between the noninvasive methods of nitric oxide measurements in bronchial asthma and allergic rhinitis and their correlation with atopic profile of Indian population.
Iranian journal of allergy, asthma, and immunology, 2011
Allergic rhinitis and asthma share common epidemiological features and inflammatory processes. The aim of the present study was to document the influence of natural allergen exposure in exhaled NO (eNO) and in spirometric parameters of patients with seasonal allergic rhinitis(SAR) and to investigate the differences among subjects with positive versus negative bronchial provocation to metacholine(BPMch).Twenty-six non-smoking patients (13F/13M; mean age 28.4ys) with a documented history of SAR, 15 healthy, non-atopic(6F/9M; mean age 37.1ys) and 6 non-symptomatic atopic subjects (3F/3M; mean age 36.5ys) were studied. At the first visit during pollen season each subject filled symptom-score card, underwent eNO and nasal NO (nNO) measurements and spirometry. BPMch was performed within the next 10 days. At the second visit out of pollen season, all measurements but BPMch were repeated. Control subjects underwent eNO and nNO measurements.eNO was significantly increased during pollen seaso...
The Effect of Air Pollution on Exhaled Nitric Oxide of Atopic and Nonatopic Subjects
Nitric Oxide, 1999
Levels of exhaled nitric oxide (NO) were determined in well-characterized atopic and nonatopic subjects on 4 days with a different level of outdoor air pollution. The two groups matched well regarding spirometric values, i.e., no difference with regard to FEV 1 , FVC, and peak flow. On the 4 test days asymptomatic atopic subjects exhaled 1.5-to 2.4-fold higher levels of NO compared with nonatopic subjects. In both groups the increase in exhaled NO in response to air pollution was similar (2.5 times maximal increase, P < 0.01). In conclusion, atopic subjects exhale higher levels of NO compared with nonatopic subjects, but respond to a similar degree to increased levels of air pollution.
2013
standardized for supporting the diagnosis in cases of eosinophilic inflammation of airways, bronchial hyperreactivity and asthma. FE NO levels have been higher in atopic than non-atopic bronchial asthma patients and some studies also reported that healthy atopic subjects without symptoms or signs of airway disorders have higher FE NO levels than non-atopic subjects. Similarly the effect of clinical atopy, with atopic cases having higher levels as compared to non-atopic cases. To the best of our knowledge, the literature on exhaled breath and nasal nitric oxide from India is lacking. Hence, this study was undertaken to answer the question about the relationship between the noninvasive methods of nitric oxide measurements in bronchial asthma and allergic rhinitis and their correlation with atopic profile of Indian population.
Exhaled nitric oxide in seasonal allergic rhinitis: influence of pollen season and therapy
Clinical <html_ent glyph="@amp;" ascii="&"/> Experimental Allergy, 2001
Exhaled nitric oxide (eNO) has been proposed as a potential indirect marker of lower airway inflammation in asthma. To investigate the existence of lower airways inflammation in allergic rhinitis eNO measurements were performed in 32 patients with symptomatic and asymptomatic seasonal allergic rhinitis early in and out of pollen seasons and in 80 healthy volunteers. To further define how exhaled NO is modified by therapy, NO levels were detected following 1-month treatment with either inhaled steroids or nonsteroids therapy with nedocromil. Exhaled NO (mean^SE) was significantly elevated in patients with seasonal allergic rhinitis with and without symptoms (24.2 1 2.5 and 13.9 1 2.9 ppb, respectively) as compared to healthy volunteers (4.5 1 0.3 ppb) both in and out of pollen season (21.2 1 2.1 and 9.0 1 1.4 p.p.b., respectively) with a higher increase during the allergen exposure in season. Higher levels of exhaled NO were detected in patients with symptoms, either from the upper or lower airways, and with bronchial hyperreactivity. The increased exhaled NO in symptomatic patients was reduced only by inhaled steroids and not by nedocromil. These findings possibly suggest the existence of lower airway inflammation in both symptomatic and asymptomatic patients with seasonal allergic rhinitis in and out of pollen season. Thus, exhaled NO may be used as a non-invasive index for early detection of lower airway inflammation and for monitoring the optional treatment in patients with seasonal allergic rhinitis.
Role of exhaled nitric oxide as a predictor of atopy
Respiratory Research, 2013
Background The fractional exhaled nitric oxide (FeNO) is a quantitative, noninvasive and safe measure of airways inflammation that may complement the assessment of asthma. Elevations of FeNO have recently been found to correlate with allergic sensitization. Therefore, FeNO may be a useful predictor of atopy in the general population. We sought to determine the diagnostic accuracy of FeNO in predicting atopy in a population-based study. Methods We conducted a cross-sectional study in an age- and sex- stratified random sample of 13 to 15 year-olds in two communities in Peru. We asked participants about asthma symptoms, environmental exposures and sociodemographics, and underwent spirometry, assessment of FeNO and an allergy skin test. We used multivariable logistic regression to model the odds of atopy as a function of FeNO, and calculated area-under-the-curves (AUC) to determine the diagnostic accuracy of FeNO as a predictor of atopy. Results Of 1441 recruited participants, 1119 (83%...
European Respiratory Journal, 1999
Exhaled nitric oxide is a potential marker of lower airway inflammation. Allergic rhinitis is associated with asthma and bronchial hyperresponsiveness. To determine whether or not nasal and exhaled NO concentrations are increased in allergic rhinitis and to assess the relation between hyperresponsiveness and exhaled NO, 46 rhinitic and 12 control subjects, all nonasthmatic nonsmokers without upper respiratory tract infection, were randomly selected from a large-scale epidemiological survey in Central Norway. All were investigated with flow±volume spirometry, methacholine provocation test, allergy testing and measurement of nasal and exhaled NO concentration in the nonpollen season. Eighteen rhinitic subjects completed an identical follow-up investigation during the following pollen season. Exhaled NO was significantly elevated in allergic rhinitis in the nonpollen season, especially in perennially sensitized subjects, as compared with controls (p=0.01), and increased further in the pollen season (p=0.04), mainly due to a twofold increase in those with seasonal sensitization. Nasal NO was not significantly different from controls in the nonpollen season and did not increase significantly in the pollen season. Exhaled NO was increased in hyperresponsive subjects, and decreased significantly after methacholine-induced bronchoconstriction, suggesting that NO production occurs in the peripheral airways. In allergic rhinitis, an increase in exhaled nitric oxide on allergen exposure, particularly in hyperresponsive subjects, may be suggestive of airway inflammation and an increased risk for developing asthma.
Exhaled and nasal nitric oxide is increased in laboratory animal allergy
Clinical <html_ent glyph="@amp;" ascii="&"/> Experimental Allergy, 1998
Background Allergens from rats, mice, guinea pigs or rabbits cause up to 30% of exposed persons to develop specific immunoglobulin E (IgE) responses. Laboratory animal allergy (LAA) is among the highest occupational risks for asthma in the UK. Elevated levels of nitric oxide (NO) are found in exhaled breath in asthma. In LAA symptoms may progress from conjunctivitis, rhinitis to asthma. Health surveillance aims to detect early sensitization. Objective To assess whether an association exists between LAA and exhaled NO. Methods A cross-sectional study was performed in 39 laboratory workers undergoing LAA health surveillance. Volunteers completed two health questionnaires, had skin-prick tests, spirometry, total IgE and RAST tests. Exhaled and nasal NO was measured by chemiluminescence analyser (LR2000, Logan Research, Rochester, UK). Results There were 23 asymptomatic subjects (mean age 29.53 yearss) and 16 symptomatic subjects (29.63 yearss, P ¼ 0.95); 9 early LAA, seven LAA asthma. Exhaled NO was raised in those with LAA symptoms 17.97 ppb Ϯ 1.24 (mean Ϯ SEM) compared with asymptomatics 6.08 ppb Ϯ 1.15, P < 0.05. A trend of increased NO by allergic status was observed; asymptomatic, to early LAA, to asthma. One-way analysis of variance compared differences between groups (F ratio 13.93, P < 0.001). Symptomatic subjects also had raised nasal NO, vs asymptomatic subjects (mean difference 378 ppb, P < 0.05). A trend was again observed by allergic status (F ratio 5.28, P ¼ 0.01). Conclusion Raised NO levels in LAA increasing with symptom severity suggest NO may prove a useful additional tool in monitoring for LAA, and possibly the response to exposure reduction or allergy due to other respiratory sensitizers.
Background: Concentration of nitric oxide in exhaled air (FeNO) was revealed to decrease as a result of immunotherapy. However, individuals who are exposed to environmental allergens are characterized by elevated values of FeNO. The aim of this study was to analyze the effects of subcutaneous immunotherapy (SCIT) on the dynamics of FeNO determined during consecutive pollination seasons. Methods: This study, performed between 2005 and 2008, included 41 patients with confirmed sensitivity to grass pollens and predominating symptoms of seasonal allergic rhinitis, randomly assigned to desensitization by preseasonal or maintenance SCIT. FeNO was measured prior to and during each pollen season (November– January and May–July, respectively). The results were conferred to data on grass pollination intensity in 2006– 2008 (air concentration of grass pollen grains, seasonal number of days when air concentration of grass pollen reached at least 50 grains per 1m3). Results: Median content of FeNO in exhaled air was significantly higher in 2007 compared to 2006 and 2008 pollen seasons. During 2007 and 2008 pollen seasons, significant increase in FeNO was observed compared to the respective preseasonal values. Median number of days with air concentration of grass pollen ‡ 50 grains per 1m3 of air during 4 weeks preceding seasonal FeNO measurement was significantly higher in 2007, corresponding to higher FeNO value recorded during this pollen season. However, no significant correlation was observed between seasonal number of days with ‡ 50 grass pollen grains per 1m3 of air and FeNO in exhaled air (r¼0.09, p¼0.362). Conclusions: Most seasonal allergic rhinitis patients show physiological levels of FeNO prior to the pollen seasons and a marked increase in this parameter, probably proportional to pollination intensity, is observed within the seasons. ISRCTN Registry: ISRCTN86562422 JOURNAL OF AEROSOL MEDICINE AND PULMONARY DRUG DELIVERY, Volume 25, Number 3, 2012 DOI: 10.1089/jamp.2011.0917