Clinical and atopic parameters and airway inflammatory markers in childhood asthma: a factor analysis

A common model for the breathlessness experience across cardiorespiratory disease

Chronic breathlessness occurs across many different conditions, often independently of disease severity. Yet, despite being strongly linked to adverse outcomes, the consideration of chronic breathlessness as a stand-alone therapeutic target remains limited. Here we use data-driven techniques to identify and confirm the stability of underlying features (factors) driving breathlessness across different cardiorespiratory diseases. Questionnaire data on 182 participants with main diagnoses of asthma (21.4%), COPD (24.7%), heart failure (19.2%), idiopathic pulmonary fibrosis (18.7%), other interstitial lung disease (2.7%), and "other diagnoses" (13.2%) were entered into an exploratory factor analysis (EFA). Participants were stratified based on their EFA factor scores. We then examined model stability using 6-month follow-up data and established the most compact set of measures describing the breathlessness experience. In this dataset, we have identified four stable factors that underlie the experience of breathlessness. These factors were assigned the following descriptive labels: 1) body burden, 2) affect/mood, 3) breathing burden and 4) anger/frustration. Stratifying patients by their scores across the four factors revealed two groups corresponding to high and low burden. These two groups were not related to the primary disease diagnosis and remained stable after 6 months. In this work, we identified and confirmed the stability of underlying features of breathlessness. Previous work in this domain has been largely limited to single-diagnosis patient groups without subsequent re-testing of model stability. This work provides further evidence supporting disease independent approaches to assess breathlessness.

Association Between Pulmonary Function and Asthma Symptoms

BACKGROUND

FEV₁ as a percentage of predicted (FEV₁%pred) is commonly measured in asthma clinical studies; however, reports vary on its association with asthma control instruments evaluating symptoms.

OBJECTIVE

Assess the association between FEV₁%pred and Asthma Control Questionnaire (ACQ) scores in a managed-care population with persistent asthma.

METHODS

Retrospective analysis of survey responses and spirometry results of patients (aged ≥12 years) with persistent asthma from the Observational Study of Asthma Control and Outcomes was done. Eligible patients received 4 identical surveys including the 5-item ACQ (ACQ-5)/6-item ACQ (ACQ-6) and completed spirometry in parallel. Longitudinal analyses, comparisons of change over time, and fixed- and random-effects regression analyses were conducted, with/without adjustment for covariates.

RESULTS

There were 1748 survey responses with valid spirometry results. In unadjusted models, coefficients for ACQ-5/ACQ-6 scores were not statistically significant and coefficient of determination (R²) was low (0.03). When adjusted for covariates, ACQ-5 and ACQ-6 scores were significantly associated with FEV₁%pred (P < .001) and R² increased to 0.11 and 0.12, respectively. In adjusted models, every 1-point increase in ACQ-5 and ACQ-6 scores was associated with a 1.7% and 1.9% decrease, respectively, in FEV₁%pred. Change in FEV₁%pred and change in ACQ-5/ACQ-6 scores were not significantly associated in regressions with/without covariates.

CONCLUSIONS

The weak and statistically insignificant association between FEV₁%pred and ACQ-5/ACQ-6 scores in unadjusted models suggests a high degree of unexplained variation between these measures. Results support the use of both symptoms and pulmonary function, rather than relying on one measure alone, to assess asthma control in clinical care and outcomes studies.

Identification of Asthma Subtypes Using Clustering Methodologies

Asthma is a heterogeneous disease comprising a number of subtypes which may be caused by different pathophysiologic mechanisms (sometimes referred to as endotypes) but may share similar observed characteristics (phenotypes). The use of unsupervised clustering in adult and paediatric populations has identified subtypes of asthma based on observable characteristics such as symptoms, lung function, atopy, eosinophilia, obesity, and age of onset. Here we describe different clustering methods and demonstrate their contributions to our understanding of the spectrum of asthma syndrome. Precise identification of asthma subtypes and their pathophysiological mechanisms may lead to stratification of patients, thus enabling more precise therapeutic and prevention approaches.

The analysis of volatile organic compounds in exhaled breath and biomarkers in exhaled breath condensate in children - clinical tools or scientific toys?

Current monitoring strategies for respiratory diseases are mainly based on clinical features, lung function and imaging. As airway inflammation is the hallmark of many respiratory diseases in childhood, noninvasive methods to assess the presence and severity of airway inflammation might be helpful in both diagnosing and monitoring paediatric respiratory diseases. At present, the measurement of fractional exhaled nitric oxide is the only noninvasive method available to assess eosinophilic airway inflammation in clinical practice. We aimed to evaluate whether the analysis of volatile organic compounds (VOCs) in exhaled breath (EB) and biomarkers in exhaled breath condensate (EBC) is helpful in diagnosing and monitoring respiratory diseases in children. An extensive literature search was conducted in Medline, Embase and PubMed on the analysis and applications of VOCs in EB and EBC in children. We retrieved 1165 papers, of which nine contained original data on VOCs in EB and 84 on biomarkers in EBC. These were included in this review. We give an overview of the clinical applications in childhood and summarize the methodological issues. Several VOCs in EB and biomarkers in EBC have the potential to distinguish patients from healthy controls and to monitor treatment responses. Lack of standardization of collection methods and analysis techniques hampers the introduction in clinical practice. The measurement of metabolomic profiles may have important advantages over detecting single markers. There is a lack of longitudinal studies and external validation to reveal whether EB and EBC analysis have added value in the diagnostic process and follow-up of children with respiratory diseases. In conclusion, the use of VOCs in EB and biomarkers in EBC as markers of inflammatory airway diseases in children is still a research tool and not validated for clinical use.

Dissociation of dysfunctional breathing and odour intolerance among adults in a general-population study

BACKGROUND

Many patients present with a mixture of respiratory problems such as shortness of breath, heavy breathing, coughing and odour intolerance. If these patients are diagnosed as asthma, it might sometimes be a false diagnosis. Concepts such as sensory hyperreactivity, hyperventilation, asthma-like symptoms, odour intolerance and dysfunctional breathing are used to refer to these patients. Non-respiratory symptoms such as headache, fatigue and bloating are sometimes also part of the clinical picture. Our aim was to use factor analysis to increase our understanding of breathing-related symptoms in a general-population frame.

METHODS

A respiratory questionnaire was answered by 10 108 subjects in a general-population sample. Items aiming to identify individuals with breathing-related symptoms and asthma were included. We used factor analysis with Varimax rotation to extract discriminatory components (i.e. groups of symptoms), based on the questionnaire items. The aim was to find groups of items (factors) as distinct as possible, still allowing overlap and showing the importance of each item in the separated factor.

RESULTS

Five distinct factors were identified in the factor analysis, representing dysfunctional breathing, odour intolerance, asthma, bronchitis and a group with mixed symptoms, respectively. These five factors explained 55% of the variance.

CONCLUSIONS

Based on our findings, we conclude that non-asthmatic breathing-related symptoms may be separated into at least two categories in a general population, odour intolerance and dysfunctional breathing. These two categories seem to be two distinct groups of subjects with breathing-related symptoms and may represent different clinical entities separated from asthma and bronchitis.

Increased proportions of CCR4(+) cells among peripheral blood CD4(+) cells and serum levels of allergen-specific IgE antibody in canine chronic rhinitis and bronchitis

Canine chronic rhinitis (CR) and bronchitis (CB) are suspected to be allergic diseases. The present study tested whether dogs diagnosed with CR or CB present an atopic predisposition based on the ratio of CC chemokine receptor 4 (CCR4)-positive cells among peripheral blood CD4-positive cells (CCR4/CD4) and the serum levels of allergen-specific IgE antibodies. We found that most dogs with CR and CB have a possibility of atopic predisposition, and macrolide therapy constitutes an alternative to corticosteroid therapy in controlling the clinical signs.

Dual role of interleukin-23 in epicutaneously-sensitized asthma in mice

BACKGROUND

Interleukin (IL)-23/Th17 axis plays an important role in the pathophysiology of asthma and eczema, however, there are some conflicting data about the effects of this system on allergic airway inflammation. In the present study, we aim to dissect the spatiotemporal differences in the roles of IL-23 in an epicutaneously-sensitized asthma model of mice.

METHODS

C57BL/6 mice were sensitized to ovalbumin (OVA) by patch application on the skin, followed by airway exposure to aerosolized OVA. During sensitization and/or challenge phase, either a specific neutralizing antibody (Ab) against IL-23 or control IgG was injected intraperitoneally. On days 1 and 8 after the final OVA exposure, airway inflammation and responsiveness to methacholine, immunoglobulin levels in serum, and cytokine release from splenocytes were evaluated. Skin Il23a mRNA levels were evaluated with quantitative RT-PCR.

RESULTS

Patch application time-dependently increased the expression of Il23a mRNA expression in the skin. Treatment with the anti-IL-23 Ab during sensitization phase alone significantly reduced the number of eosinophils in bronchoalveolar lavage fluids and peribronchial spaces after allergen challenge compared with treatment with control IgG. Anti-IL-23 Ab also reduced serum levels of OVA-specific IgG1. In contrast, treatment with the anti-IL-23 Ab during the challenge phase alone rather exacerbated airway hyperresponsiveness to methacholine with little effects on airway eosinophilia or serum IgG1 levels.

CONCLUSIONS

IL-23 expressed in the skin during the sensitization phase plays an essential role in the development of allergic phenotypes, whereas IL-23 in the airways during the challenge phase suppresses airway hyperresponsiveness.

Recent advances in asthma biomarker research

Asthma is characterized by recurrent and reversible airflow obstruction, which is routinely monitored by history and physical examination, spirometry and home peak flow diaries. As airway inflammation is central to asthma pathogenesis, its monitoring should be part of patient management plans. Fractional exhaled nitric oxide level (FeNO) is the most extensively studied biomarker of airway inflammation, and FeNO references were higher in Chinese (Asians) than Whites. Published evidence was inconclusive as to whether FeNO is a useful management strategy for asthma. Other biomarkers include direct (histamine, methacholine) and indirect (adenosine, hypertonic saline) challenges of bronchial hyperresponsiveness (BHR), induced sputum and exhaled breath condensate (EBC). A management strategy that normalized sputum eosinophils among adult patients resulted in reductions of BHR and asthma exacerbations. However, subsequent adult and pediatric studies failed to replicate these benefits. Asthma phenotypes as defined by inflammatory cell populations in sputum were also not stable over a 12-month period. A recent meta-analysis concluded that induced sputum is not accurate enough to be applied in routine monitoring of childhood asthma. There is poor correlation between biomarkers that reflect different asthma dimensions: spirometry (airway caliber), BHR (airway reactivity) and FeNO or induced sputum (airway inflammation). Lastly, EBC is easily obtained noninvasively by cooling expired air. Many biomarkers ranging from acidity (pH), leukotrienes, aldehydes, cytokines to growth factors have been described. However, significant overlap between groups and technical difficulty in measuring low levels of inflammatory molecules are the major obstacles for EBC research. Metabolomics is an emerging analytical method for EBC biomarkers. In conclusion, both FeNO and induced sputum are useful asthma biomarkers. However, they will only form part of the clinical picture. Longitudinal studies with focused hypotheses and well-designed protocols are needed to establish the roles of these biomarkers in asthma management. The measurement of biomarkers in EBC remains a research tool.

Chemokine profiles in blood associated with delayed asthmatic response to allergen challenge

BACKGROUND

Patients with bronchial asthma having been challenged with allergen develop various types of asthmatic response, such as immediate (IAR), late (LAR) or delayed (DYAR) response, due to different immunologic mechanisms. The DYAR, beginning 26-32 h, reaching maximum between 32 and 48 h and resolving within 56 h after the challenge, differs from IAR and LAR in clinical and immunologic features.

OBJECTIVES

To investigate the changes in the serum concentrations of chemokines associated with the isolated form of DYAR.

METHODS

In 22 patients the repeated DYAR (p < 0.001) was supplemented with recording of blood cell counts and serum concentrations of chemokines before, and up to 72 h after the bronchial challenge by means of enzyme-linked immunoassay, (ELISA).

RESULTS

The DYAR was associated with (a) significantly increased serum concentrations (p < 0.05) of CCL 2, CCL 3, CCL 4, CCL 7, CCL 20, CXCL 1, CXCL 8, CXCL 9, CXCL 10 and CXCL 11, and (b) significantly decreased serum concentrations, (p < 0.05) of CCL 5, CCL 11, CCL 17, CCL 22, CCL 24 and CCL 26, as compared with their pre-challenge as well as the PBS control values. No significant chemokine changes were recorded during the PBS controls (p > 0.1).

CONCLUSIONS

These results, together with changes in the blood cell counts, provide evidence for an involvement of activated Th(1), cells and NK cells (CCL-2, -3, -4, -20, CXCL-9,-10,-11), neutrophils (CCL-20, CXCL-1,-8) and monocytes (CCL-2,-3,-4, -7, CXCL-10), upon co-operation of other cell types, such as epithelial, endothelial and dendritic cells, in the immunologic mechanism(s) underlying the DYAR.

Total serum immunoglobulin e in children with asthma

Immunoglobulin (Ig) E has been shown to be a major contributing factor for the development of bronchial hyperresponsiveness in asthma. An elevation in serum IgE levels contributes to asthma and is considered a potent predictor of the development of asthma. The objectives of the present study were to estimate the levels of total serum IgE in asthmatic and healthy control subjects and to investigate the relationship of various demographic and clinical characteristics with the total serum IgE level in asthmatics. We measured the levels of total serum IgE using the ELISA kits (AccuBind, Monobind Inc., USA). The relevant demographic and clinical data were obtained using the questionnaire. The results showed that asthmatic children had significantly elevated level of total serum IgE compared to that of the healthy controls. The levels of total IgE and IL-4 in sera of 44 asthmatic children showed a significant positive correlation. Total serum IgE >150 IU/mL was found to be significantly associated with the age, exposure to cigarette smoke, and raised eosinophil count in asthmatic children. In conclusion, the elevated level of total serum IgE may demonstrate the allergic etiology of asthma in the subjects studied.

Serum TARC and CTACK concentrations in children with atopic dermatitis, allergic asthma, and urticaria

BACKGROUND

  Thymus and activation-regulated chemokine (TARC/CCL17) and cutaneous T cell-attracting chemokine (CTACK/CCL27) belong to the CC chemokine family, which plays an important role in immune-inflammatory processes. It has been demonstrated that serum concentrations of TARC and CTACK are increased in patients with various allergic diseases.

AIM

  To compare serum TARC and CTACK concentrations between children with different clinical manifestation of mast cell-dependent diseases, such as atopic allergy and urticaria.

METHODS

  A total of 87 children including 26 with mild to severe atopic dermatitis (AD), 43 children with controlled allergic asthma symptoms (treated and untreated with anti-inflammatory drugs), and 18 children with urticaria were recruited into the study. The control group consisted of 31 healthy non-atopic children.

RESULTS

  Serum concentrations of TARC and CTACK were significantly higher in children with AD than in healthy controls. No significant differences in serum concentrations of the chemokines between asthmatics, urticaria patients, and healthy controls were found. The severity of AD symptoms significantly correlated with serum CTACK and TARC concentrations.

CONCLUSION

  These findings, in conjunction with earlier data, indicate that differences may exist in circulating concentrations of TARC and CTACK, between patients with atopic allergy and urticaria.

Evaluation of the National Heart, Lung, and Blood Institute guidelines impairment domain for classifying asthma control and predicting asthma exacerbations

BACKGROUND

Accurate assessment of asthma control may help predict future asthma exacerbations.

OBJECTIVE

To evaluate asthma guidelines impairment domain components as predictors of exacerbations in severe/difficult-to-treat asthma.

METHODS

Children (aged 6-11 years; n = 289) and adolescents/adults (aged ≥ 12 years; n = 2,094) with complete baseline and 12-month data from The Epidemiology and Natural History of Asthma Outcomes and Treatment Regimens study were included. Asthma was categorized as very poorly controlled, not well-controlled, and well-controlled using impairment domain components. Effects of omitting each component on very poorly controlled and not well controlled groups were examined. Multivariable logistic regression determined the relationship of components in predicting asthma exacerbations.

RESULTS

Omission of individual impairment domain components led to misclassification of asthma control in 11% to 39% of patients. A baseline exacerbation was the strongest independent predictor of exacerbation at month 12 in children (odds ratio = 2.94; P < .001) and adolescents/adults (odds ratio = 2.93; P < .001). In children, very poorly controlled asthma-based short-acting β2-agonist use was associated with a 2-fold higher exacerbation risk (odds ratio = 2.03; P = .011). In adolescents/adults, not well controlled or very poorly controlled asthma based on short-acting β2-agonist use (odds ratio = 1.49), lung function (odds ratio = 1.66), and the Asthma Therapy Assessment Questionnaire (odds ratio = 1.94) were also independent predictors of exacerbations (P < .001).

CONCLUSIONS

Although the combined use of individual components of the impairment domain increases the sensitivity of identifying patients at high risk for future asthma exacerbations, specific components may be more important than others in severe/difficult-to-treat asthma. Prior exacerbations, short-acting β2-agonist use, lung function, and (in adolescents/adults) the Asthma Therapy Assessment Questionnaire were independent predictors of exacerbations.

Exhaled nitric oxide is associated with allergic inflammation in children

Exhaled nitric oxide (eNO) has been proposed as a noninvasive marker of airway inflammation in asthma. In asthmatic patients, exhaled NO levels have been shown to relate with other markers of eosinophilic recruitment, which are detected in blood, sputum, bronchoalveolar lavage fluid and bronchial biopsy samples. The purpose of this study was to assess the possible relationship between eNO and allergic inflammation or sensitization in childhood asthma and allergic rhinitis. Subjects consisted of 118 asthmatic children, 79 patients with allergic rhinitis, and 74 controls. Their age ranged from 6 to 15 yr old. eNO level, peripheral blood eosinophil count, eosinophil cationic protein (ECP), serum total IgE level and specific IgE levels were measured. Methacholine challenge test and allergic skin prick test for common allergens were performed in all subjects. Atopic group (n = 206, 44.48 ± 30.45 ppb) had higher eNO values than non-atopic group (n = 65, 20.54 ± 16.57 ppb, P < 0.001). eNO level was significantly higher in patients with asthma (42.84 ± 31.92 ppb) and in those with allergic rhinitis (43.59 ± 29.84 ppb) than in healthy controls (27.01 ± 21.34 ppb, P < 0.001) but there was no difference between asthma and allergic rhinitis group. eNO also had significant positive correlations with Dermatophagoides pteronyssinus IgE level (r = 0.348, P < 0.001), Dermatophagoides farinae IgE level (r = 0.376, P < 0.001), and the number of positive allergens in skin prick test (r = 0.329, P = 0.001). eNO had significant positive correlations with peripheral blood eosinophil count (r = 0.356, P < 0.001), serum total IgE level (r = 0.221, P < 0.001), and ECP (r = 0.436, P < 0.001). This study reveals that eNO level is associated with allergic inflammation and the degree of allergic sensitization.

Hepatotoxicity or hepatoprotection? Pattern recognition for the paradoxical effect of the Chinese herb Rheum palmatum L. in treating rat liver injury

The hepatotoxicity of some Chinese herbs has been a cause for concern in recent years. However, some herbs, such as rhubarb, have been documented as having both therapeutic and toxic effects on the liver, leading to the complex problem of distinguishing the benefits from the risks of using this herb. To comparatively analyze the dose-response relationship between rhubarb and hepatic health, we administrated total rhubarb extract(RE) to normal and carbon tetrachloride(CCl₄)-treated rats for 12 weeks at 4 dosage levels(2.00, 5.40, 14.69 and 40.00 g·kg⁻¹, measured as the quantity of crude material), followed by biochemical and histopathological tests of the rats' livers. A composite pattern was extracted by factor analysis, using all the biochemical indices as variables, into a visual representation of two mathematically obtained factors, which could be interpreted as the fibrosis factor and the cellular injury factor, according to the values of the variable loadings. The curative effect of administering the two lowest dosages of RE to CCl₄-treated rats was mainly expressed as a decrease in the extent of cellular injury. The hepatoprotective mechanism of RE might be related to its antioxidant effect, the antagonism of the free radical damage to hepatocytes caused by CCl₄. By contrast, the RE-induced liver damage was mainly expressed as a significant increase in the amount of fibrosis in both normal rats at all dosage levels and CCl₄-treated rats at the two highest dosage levels. Therefore, the hepatotoxic potential of RE could be attributable to the liver cell fibrosis induced by high doses of the herb. This study illustrates the bidirectional potential of rhubarb and demonstrates the feasibility of using factor analysis to study the dose-response relationships between herbal medicines and hepatotoxicity or the healing effects of these herbs by extracting the underlying interrelationships among a number of functional bio-indices in a holistic manner.

Genetic variations in nitric oxide synthase and arginase influence exhaled nitric oxide levels in children

BACKGROUND

Exhaled nitric oxide (FeNO) is a biomarker of airway inflammation. In the nitric oxide (NO) synthesis pathway, nitric oxide synthases (encoded by NOS1, NOS2A, and NOS3) and arginases (encoded by ARG1 and ARG2) compete for L-arginine. Although FeNO levels are higher in children with asthma/allergy, influence of these conditions on the relationships between variations in these genes and FeNO remains unknown. The aims of the study were to evaluate the role of genetic variations in nitric oxide synthases and arginases on FeNO in children and to assess the influence of asthma and respiratory allergy on these genetic associations.

METHODS

Among children (6-11 years) who participated in the southern California Children's Health Study, variations in these five genetic loci were characterized by tagSNPs. FeNO was measured in two consecutive years (N = 2298 and 2515 in Years 1 and 2, respectively). Repeated measures analysis of variance was used to evaluate the associations between these genetic variants and FeNO.

RESULTS

Sequence variations in the NOS2A and ARG2 loci were globally associated with FeNO (P = 0.0002 and 0.01, respectively). The ARG2 association was tagged by intronic variant rs3742879 with stronger association with FeNO in asthmatic children (P-interaction = 0.01). The association of a NOS2A promoter haplotype with FeNO varied significantly by rs3742879 genotypes and by asthma.

CONCLUSION

Variants in the NO synthesis pathway genes jointly contribute to differences in FeNO concentrations. Some of these genetic influences were stronger in children with asthma. Further studies are required to confirm our findings.

Inflammatory markers in childhood asthma

The major characteristic of asthma is persistent airway inflammation that fails to resolve spontaneously. Dysregulation of pro- and anti-inflammatory mechanisms is responsible for the development of chronic inflammation. The inflammatory reaction is mediated by numerous cells and their mediators. Detection and quantification of airway inflammation in children are subject to many requirements, e.g., use of biologic samples obtained in a non-invasive way; use of standardized analytical methods to determine biomarkers that can identify inflammation processes (inflammation itself, oxidative stress, apoptosis and remodelling); determining the role of systemic inflammation; assessment of correlation of various biomarkers of inflammation with clinical parameters and their diagnostic efficacy; providing a tool(s) to monitor diseases, and to evaluate adequacy of therapy; and predicting the clinical course of inflammation and prognosis of asthma. Using standardized analyses, it is now possible to determine direct markers of local inflammation, i.e., fractional nitric oxide (marker of oxidative stress) in exhaled breath, pH (marker of acid stress) in breath condensate, and indirect markers in blood/serum, i.e., eosinophil granulocytes (indicating migration), eosinophil cationic protein (marker of activated eosinophil granulocytes) and C-reactive protein (marker of systemic inflammation). However, none of these biomarkers are specific for asthma. Further standardization of the known pulmonary biomarkers of local inflammation and identification of new ones will allow for longitudinal follow-up of inflammation in children with asthma.

Exhaled breath condensate nitrates, but not nitrites or FENO, relate to asthma control

BACKGROUND

Asthma is a chronic respiratory disease, characterised by airways inflammation, obstruction and hyperresponsiveness. Asthma control is the goal of asthma treatment, but many patients have sub-optimal control. Exhaled NO and exhaled breath condensate (EBC) NO metabolites (nitrites and nitrates) measurements are non-invasive tools to assess airways inflammation. Our aim was to investigate the relationships between asthma control and the above-named biomarkers of airways inflammation.

METHODS

Thirty-nine non-smoking asthmatic patients (19 women) aged 50 (21-80) years performed measurements of exhaled NO (FENO), EBC nitrates, nitrites and pH, and answered Asthma Control Questionnaire (ACQ) and Asthma Control Test (ACT)-questionnaire.

RESULTS

The ACT and ACQ score were strongly interrelated (ρ = -0.84, p < 0.001). No relationships between ACT or ACQ score and FENO were found (p > 0.05). EBC nitrates were negatively related to ACT score (ρ = -0.34, p = 0.03) and positively related to ACQ score (ρ = 0.41, p = 0.001) while no relation of EBC nitrites to either ACQ or ACT score was found (p>0.05).

CONCLUSION

EBC nitrates were the only biomarker that was significantly related to asthma control. This suggests that nitrates, but not nitrites or FENO, reflect an aspect of airways inflammation that is closer related to asthma symptoms. Therefore there is a potential role for EBC nitrates in objective assessment of asthma control.

Eotaxin in exhaled breath condensate of allergic asthma patients with exercise-induced bronchoconstriction

BACKGROUND

Eosinophils are the key inflammatory cells in asthma, and more and more evidence suggests their crucial role in exercise-induced bronchoconstriction (EIB). Eotaxin, as the most important chemotactic factor for eosinophils, plays an important role in the pathogenesis of asthma.

OBJECTIVES

The aim of the study was to evaluate the changes in eotaxin levels in exhaled breath condensate (EBC) following intensive exercise in allergic asthmatics.

METHODS

The study was performed in a group of 27 asthmatics (17 with EIB, 13 without EIB) and 9 healthy volunteers. Changes induced by intensive exercise in the concentrations of eotaxin in EBC during the 24 h after an exercise test were assessed. The possible correlations of these measurements with the results of other tests commonly associated with eosinophilic airway inflammation were also determined.

RESULTS

In asthmatic patients with EIB, a statistically significant increase in eotaxin concentrations in EBC collected during the first 24 h after an exercise test - with maximal increase after 6 h - was revealed. A statistically significant correlation between the maximum increase in eotaxin concentrations in EBC after exercise, and an increase in either serum eosinophil cationic protein or F(ENO) 24 h after exercise in the group of asthmatics with EIB, was observed.

CONCLUSIONS

Our results confirm connections between EIB and airway eosinophilic inflammation. The increase of eotaxin in asthmatic airways, by promoting the migration and activation of eosinophils, may play an important role in upregulation and sustaining of the airway inflammation observed in EIB in asthmatic patients.

Association of exhaled nitric oxide to asthma burden in asthmatics on inhaled corticosteroids

BACKGROUND

Fractional exhaled nitric oxide (FENO) is a marker of airway inflammation. Its role in assessing asthma burden in clinical practice needs more study.

OBJECTIVE

To determine whether higher FENO levels are associated with greater asthma burden.

METHODS

This was a multicenter cross-sectional retrospective study of atopic 12- to 56-year-old persistent asthmatics on inhaled corticosteroids (ICS). Questionnaire and 1-year retrospective administrative data were used to analyze by unadjusted and adjusted robust Poisson regression (relative risks) and negative binomial regression [incidence rate ratios (IRRs)] the associations of masked FENO levels (NIOX MINO®) to short-acting beta-agonist (SABA) dispensings and oral corticosteroid (OCS) use in the past year independent of spirometry and an asthma control tool [Asthma Control Test (ACT)].

RESULTS

FENO levels ranged from 7-215 ppb (median 28 ppb) in 325 patients. Higher FENO levels significantly correlated with more SABA dispensings and OCS courses in the past year, lower FEV(1)% predicted levels, but not ACT score. FENO highest (≥48 ppb) versus lowest (≤19 ppb) quartile values were associated independently in the past year with ≥7 SABA canisters dispensed (relative risk=2.40, 95% CI=1.25-4.62) and total number of SABA canisters dispensed (IRR=1.46, 95% CI=1.12-1.99) and with ≥1 OCS course (relative risk=1.48, 95% CI=1.06-2.07) and total number of OCS courses (IRR=1.71, 95% CI=1.09-2.66). The significant independent relationship of higher FENO levels to increasing SABA dispensings and OCS courses was confirmed by linear trend analyses.

CONCLUSIONS

Independent and clinically meaningful associations between higher FENO levels and greater asthma burden during a prior year in persistent asthmatics on ICS suggest that FENO measurement may be a complementary tool to help clinicians assess asthma burden.

Risk factors and predictive clinical scores for asthma exacerbations in childhood

BACKGROUND

Asthma is a major public health problem that affects millions of children worldwide, and exacerbations account for most of its morbidity and costs. Primary-care providers lack efficient tools to identify children at high risk for exacerbations. We aimed to construct a clinical score to help providers to identify such children.

METHODS

Our main outcome was severe asthma exacerbation, which was defined as any hospitalization, urgent visit, or systemic steroid course for asthma in the previous year, in children. A clinical score, consisting of a checklist questionnaire made up of 17 yes-no questions regarding asthma symptoms, use of medications and health-care services, and history, was built and validated in a cross-sectional study of Costa Rican children with asthma. It was then evaluated using data from the Childhood Asthma Management Program (CAMP), a longitudinal trial cohort of North American children.

RESULTS

Compared with children at average risk for an exacerbation in the Costa Rican validation set, the odds of an exacerbation among children in the low-risk (OR, 0.2; 95% CI, 0.1-0.4) and high-risk (OR, 5.4; 95% CI, 1.5-19.2) score categories were significantly reduced and increased, respectively. In CAMP, the hazard ratios for an exacerbation after 1-year follow-up in the low-risk and high-risk groups were 0.6 (95% CI, 0.5-0.7) and 1.9 (95% CI, 1.4-2.4), respectively, with similar results at 2 years.

CONCLUSIONS

The proposed Asthma Exacerbation Clinical Score is simple to use and effective at identifying children at high and low risk for asthma exacerbations. The tool can easily be used in primary-care settings.

Eotaxin-1 in exhaled breath condensate of stable and unstable asthma patients

Background

Airway eosinophilia is considered a central event in the pathogenesis of asthma. Eotaxin plays a key role in selective eosinophil accumulation in the airways and, subsequently, their activation and degranulation. The study was undertaken to evaluate eotaxin-1 levels in the exhaled breath condensate (EBC) of asthmatics with different degrees of asthma severity and to establish the possible correlation of these measurements with other recognized parameters of airway inflammation.

Methods

EBC was collected from 46 patients with allergic asthma (14 with steroid-naïve asthma, 16 with ICS-treated, stable asthma, 16 with ICS-treated unstable asthma) and 12 healthy volunteers. Concentrations of eotaxin-1 were measured by ELISA.

Results

In the three groups of asthmatics, eotaxin-1 concentrations in EBC were significantly higher compared with healthy volunteers (steroid-naïve asthma: 9.70 pg/ml ± 1.70, stable ICS-treated asthma: 10.45 ± 2.00, unstable ICS-treated asthma: 17.97 ± 3.60, healthy volunteers: 6.24 ± 0.70). Eotaxin-1 levels were significantly higher in patients with unstable asthma than in the two groups with stable disease. We observed statistically significant correlations between the concentrations of eotaxin-1 in EBC and exhaled nitric oxide (F_ENO) or serum eosinophil cationic protein (ECP) in the three studied groups of asthmatics. We also discovered a significantly positive correlation between eotaxin-1 in EBC and blood eosinophil count in the groups of patients with unstable asthma and steroid-naïve asthma.

Conclusions

Measurements of eotaxin-1 in the EBC of asthma patients may provide another useful diagnostic tool for detecting and monitoring airway inflammation and disease severity.

Biomarkers in asthma and allergic rhinitis

A biological marker (biomarker) is a physical sign or laboratory measurement that can serve as an indicator of biological or pathophysiological processes or as a response to a therapeutic intervention. An applicable biomarker possesses the characteristics of clinical relevance (sensitivity and specificity for the disease) and is responsive to treatment effects, in combination with simplicity, reliability and repeatability of the sampling technique. Presently, there are several biomarkers for asthma and allergic rhinitis that can be obtained by non-invasive or semi-invasive airway sampling methods meeting at least some of these criteria. In clinical practice, such biomarkers can provide complementary information to conventional disease markers, including clinical signs, spirometry and PC(20)methacholine or histamine. Consequently, biomarkers can aid to establish the diagnosis, in staging and monitoring of the disease activity/progression or in predicting or monitoring of a treatment response. Especially in (young) children, reliable, non-invasive biomarkers would be valuable. Apart from diagnostic purposes, biomarkers can also be used as (surrogate) markers to predict a (novel) drug's efficacy in target populations. Therefore, biomarkers are increasingly applied in early drug development. When implementing biomarkers in clinical practice or trials of asthma and allergic rhinitis, it is important to consider the heterogeneous nature of the inflammatory response which should direct the selection of adequate biomarkers. Some biomarker sampling techniques await further development and/or validation, and should therefore be applied as a "back up" of established biomarkers or methods. In addition, some biomarkers or sampling techniques are less suitable for (very young) children. Hence, on a case by case basis, a decision needs to be made what biomarker is adequate for the target population or purpose pursued. Future development of more sophisticated sampling methods and quantification techniques, such as--omics and biomedical imaging, will enable detection of adequate biomarkers for both clinical and research applications.

Effects of antisense interleukin-5 gene transferred by recombinant adeno-associated virus to allergic rats

BACKGROUND AND OBJECTIVE

The accumulation of eosinophils in airways is an important characteristic of asthma. The process is primarily mediated by interleukin-5 (IL-5) secreted by Th2 lymphocytes. This study explored a new approach to asthma therapy in which allergic rats were transfected with the IL-5 antisense gene delivered by the recombinant adeno-associated virus (rAAV-ASIL-5).

METHODS

The viral vector rAAV-ASIL-5 was constructed and the IL-5 antisense gene transfected into allergic rats. The levels of IL-5, IgE, eotaxin and eosinophilic cationic protein (ECP) in sera and bronchoalveolar lavage fluid (BALF) were measured by ELISA. The inflammatory responses in lung tissues were evaluated by histological study.

RESULTS

The levels of IL-5 protein in serum and BALF were significantly decreased in the allergic rats treated with rAAV-ASIL-5 (P < 0.05). Serum ovalbumin-specific IgE was reduced in treated rats compared with untreated rats (P < 0.05). rAAV-ASIL-5 treatment also reduced eosinophils in the peripheral blood and BALF, as well as the ECP and eotaxin levels in serum and BALF (P < 0.05). There was significantly less inflammation in the lungs of rAAV-ASIL-5-treated rats than in those of untreated rats. No obvious pathological damage to the kidneys and livers of the rats treated with rAAV was observed.

CONCLUSIONS

Treatment with rAAV-ASIL-5 inhibited the accumulation of eosinophils and airway inflammation in the rat model of allergic asthma by suppressing IL-5 production. These results suggest that rAAV-ASIL-5-based gene therapy may be used for the treatment of allergic asthma.

Volatile organic compounds in exhaled breath as a diagnostic tool for asthma in children

BACKGROUND

The correct diagnosis of asthma in young children is often hard to achieve, resulting in undertreatment of asthmatic children and overtreatment in transient wheezers.

OBJECTIVES

To develop a new diagnostic tool that better discriminates between asthma and transient wheezing and that leads to a more accurate diagnosis and hence less undertreatment and overtreatment. A first stage in the development of such a tool is the ability to discriminate between asthmatic children and healthy controls. The integrative analysis of large numbers of volatile organic compounds (VOC) in exhaled breath has the potential to discriminate between various inflammatory conditions of the respiratory tract.

METHODS

Breath samples were obtained and analysed for VOC by gas chromatography-mass spectrometry from asthmatic children (n=63) and healthy controls (n=57). A total of 945 determined compounds were subjected to discriminant analysis to find those that could discriminate diseased from healthy children. A set of samples from both asthmatic and healthy children was selected to construct a model that was subsequently used to predict the asthma or the healthy status of a test group. In this way, the predictive value of the model could be tested.

MEASUREMENTS AND MAIN RESULTS

The discriminant analyses demonstrated that asthma and healthy groups are distinct from one another. A total of eight components discriminated between asthmatic and healthy children with a 92% correct classification, achieving a sensitivity of 89% and a specificity of 95%. Conclusion The results show that a limited number of VOC in exhaled air can well be used to distinguish children with asthma from healthy children.

Quality-of-life assessment in Chinese families with food-allergic children

BACKGROUND

Caucasian families with food-allergic children have a compromised quality of life (QoL) for fear of life-threatening food reactions. Such data are limited in Asian children. Based on our recent questionnaire-based survey, 8.1% of young children recruited from local nurseries and kindergartens had parent-reported adverse food reactions (AFRs).

OBJECTIVE

This study tested the robustness of the Chinese Food Allergy Quality of Life-Parental Burden questionnaire (FAQL-PB) and assessed QoL in families with childhood AFR. The correlations among FAQL-PB items were evaluated by factor analysis.

METHODS

Two hundred and ninety-eight of 3677 children aged 2-7 years had parent-reported AFR, and 197 (66.1%) of them completed the 17 items of our self-administered FAQL-PB. Six hundred and thirty-nine (18.9%) children without AFR returned this questionnaire. Factor analysis was used to delineate the inter-relationship among the FAQL-PB items.

RESULTS

Cronbach alpha for our Chinese FAQL-PB was 0.976, and the median (interquartile range) FAQL-PB scores of children with and without parent-reported AFR were 0.10 (0.02-0.32) and 0 (0-0.18), respectively (P < 0.001). Factor analysis confirmed excellent correlations between FAQL-PB items. The 17 items were clustered into two factors, which explained 79.7% of the total variance. Among children with AFR, FAQL-PB scores increased with increasing numbers of foods that caused AFRs (P < 0.001 for trend). Thirty (15.2%) children had impaired QoL, defined as average item FAQL-PB score > or = 0.5. Impaired QoL was associated with AFR that was caused by >3 foods (P = 0.001), current food avoidance (P = 0.005) and AFR caused by peanut (P = 0.003), egg (P = 0.011) and cow's milk (P = 0.028), and current flexural dermatitis (P = 0.011).

CONCLUSIONS

FAQL-PB is a robust measure of AFR-specific parental QoL, which is impaired in Chinese children with parent-reported AFR. Flexural dermatitis, current food avoidance and AFR caused by multiple foods are independent risk factors for lower parental QoL.

Biomarkers in exhaled breath condensate: a review of collection, processing and analysis

Exhaled breath condensate (EBC) is a potential rich source for countless biomarkers that can provide valuable information about respiratory as well as systemic diseases. EBC has been studied in a variety of diseases including allergic rhinitis, asthma, chronic obstructive lung disease, cystic fibrosis, lung cancer, and obstructive sleep apnea syndrome. Although numerous biomarkers have been discovered and studied in EBC, the methods of collection and biomarker detection have not been fully standardized. While leaving standardization methods up to individual labs for the present time is optimal for the continued discovery of new biomarkers in EBC, this decreases the reproducibility and generalizability of the findings. In this review we will discuss specific biomarkers studied in specific diseases as well as some of the related technical issues including collection, processing and analysis.

An exploration of factors underlying asthma care and morbidity: a factor analysis of clinical variables

BACKGROUND

Clinical risk models use recognized risk factors to identify patients at risk for future asthma morbidity. However, the low predictive values of these models suggest an important need to re-evaluate risk assessment strategies.

OBJECTIVE

To use exploratory factor analysis to define underlying factors operative in asthma treatment and morbidity, and characterize their interrelationships and association with 6-month morbidity.

METHODS

Children (n = 197) presenting to an emergency department for an acute asthma episode were followed for 6 months (follow-up data available for 84%). Baseline data included demographics, asthma history, current and past symptoms, and current treatment and management. Factor analysis was used to summarize the underlying relationships between variables. Correlations between factors and 6-month morbidity were calculated.

RESULTS

Factor analysis revealed that 4 factors provided a parsimonious summary of the variables. The factors were labeled current symptom severity, quality of care indicators, previous severe disease, and sociodemographic factors. Positive correlations were observed between quality of care, current symptom severity, and previous severe disease. The factor describing sociodemographic factors was inversely related to current symptom severity and quality of care. Previous severe disease significantly predicted 6-month morbidity.

CONCLUSION

Quality of care was better in subjects with increased current symptoms or previous severe disease, but poorer in individuals with adverse sociodemographic factors. Previous severe disease was the only factor associated with 6-month morbidity, suggesting that current assessment methods do not adequately account for all underlying factors likely operative in asthma morbidity.

The use of fraction of exhaled nitric oxide in pulmonary practice

The measurement of the fractional concentration of exhaled nitric oxide (FeNO) is a convenient, noninvasive, point-of-service office test for airway inflammation. The first half of this practice management review presents the methodological, interpretative, and clinical applications of FeNO. The second half discusses practical management issues, including current and future technology, equipment specifications, US Food and Drug Administration regulations, cost, current procedural terminology coding, and reimbursement. The measurement of FeNO is helpful in the diagnosis of asthma. It is predictive of a response to inhaled corticosteroids (ICSs). Monitoring FeNO is useful in maintaining asthma control by allowing the assessment of adherence to medication and dose titration of ICSs. An elevated level of FeNO is predictive of asthma relapse following corticosteroid withdrawal especially in children. The advances in technology, ease of use, and clinical utility will lead to greater availability, acceptance, and routine application in the care of asthma.

Identifying the components of asthma health status in children with mild to moderate asthma

BACKGROUND

Weak and inconsistent correlations between measurements of asthma health status suggest that the disease is composed of nonoverlapping components.

OBJECTIVE

Factor analysis was used to explore the relationships between measures of asthma morbidity and to identify heterogeneous components of asthma health status in children 5 to 12 years old. Results were compared across time (baseline and 48-month visit) and treatment arms.

METHODS

Analyses were conducted in 7 different study windows in a database from a large clinical trial of children with mild to moderate asthma (n = 1041). Measurements of lung function, symptoms, and health care utilization from daily diary cards, serum IgE levels, total eosinophil count, skin test positivity, and airway hyperresponsiveness were included. Data on fractional exhaled nitric oxide and sputum eosinophil cationic protein were included in a subgroup of patients.

RESULTS

In each of the study windows, factor analysis identified 5 factors that explained between 50% and 60% of the common variance. Factors identified included (1) inflammatory markers, (2) symptoms/medication use, (3) asthma exacerbations, and measures of lung function, which subdivided into (4) FEV(1) and forced vital capacity, and (5) bronchodilator response and the FEV(1)/forced vital capacity ratio. Exploratory analyses suggest that fractional exhaled nitric oxide account for the atopy/inflammatory marker factor, and sputum measurements account for a sixth, separate factor.

CONCLUSION

The consistent identification of a 5-factor structure across time and treatment arms suggests that each of these factors provides independent information in the assessment of asthma.

Exhaled nitric oxide and biomarkers in exhaled breath condensate indicate the presence, severity and control of childhood asthma

BACKGROUND

Exhaled nitric oxide and inflammatory biomarkers in exhaled breath condensate may be useful to diagnose and monitor childhood asthma. Their ability to indicate an asthma diagnosis, and to assess asthma severity and control, is largely unknown.

OBJECTIVE

To study (1) the ability of exhaled nitric oxide and inflammatory markers in exhaled breath condensate (nitrite, nitrate, hydrogen peroxide, 8-isoprostane, IFN-gamma, TNF-alpha, IL-2, -4, -5, -10 and acidity) to discriminate between childhood asthma and controls. (2) The ability of these biomarkers to indicate asthma severity and control.

METHODS

One-hundred and fourteen children were included: 64 asthmatics (10.7+/-3.0 years, 67.2% atopic) and 50 controls (10.0+/-0.4 years). Condensate was collected using a glass condenser.

RESULTS

Exhaled nitric oxide, IFN-gamma and IL-4 in exhaled breath condensate differed significantly between asthma and controls. Multivariate backward logistic regression models demonstrated that IL-4 (odds ratio 7.9, 95% confidence interval 1.2-51.0) was the only significant indicator of an asthma diagnosis. Asthma control was best assessed by exhaled nitric oxide, 8-isoprostane, IFN-gamma and IL-4 (sensitivity 82%, specificity 80%, P<0.05), whereas exhaled nitric oxide, 8-isoprostane, nitrate and nitrite in condensate were the best indicators of asthma severity (sensitivity 89%, specificity 72%, P<0.05).

CONCLUSION

Different markers in condensate are of an additional value to exhaled nitric oxide, and are needed in non-invasive inflammometry. They could be useful to diagnose asthma and to indicate asthma control and severity in childhood.

Exhaled nitric oxide: interactions between asthma, hayfever, and atopic dermatitis in school children

BACKGROUND

Clinicians frequently rely on reported symptoms and basic pulmonary function testing to assess asthma prevalence in the community. However, given that spirometry results are often normal for asthmatic children and the fact that there is no equivalent word for 'wheeze' in languages other than English, the assessment of asthma prevalence can be troublesome.

OBJECTIVE

To evaluate in a population based setting, whether FeNO as a non-invasive marker, contributes to the detection of asthma.

METHODS

This cross-sectional study was carried out on primary school children from Northern and Southern Tyrol. FeNO measurements were made using the online single breath technique prior to spirometry. Symptom status including asthma, hayfever and atopic dermatitis was determined by the ISAAC questionnaire.

RESULTS

Six hundred and forty-four Tyrolean children aged 8-10 years participated. In terms of FEV1 % predicted, the asthma and hayfever group had significantly lower values compared to the asymptomatic group, the hayfever only, and the atopic dermatitis only groups. For FeNO, participants with asthma and hayfever, asthma and atopic dermatitis, and hayfever only recorded significantly greater FeNO values when compared to the asymptomatic group. Moreover, the asthma and atopic dermatitis group recorded significantly greater FeNO when compared to the asthma only group. Multivariate regression revealed that asthma had a small significant inverse association with FEV1 % predicted for the individual model and when combined with hayfever. For FeNO, each of the individual and combined model analyses achieved significance.

CONCLUSION

Although FeNO appears to be influenced by asthma, the presence of other atopic conditions confounds the relationship. Elevated levels of FeNO do not distinguish between asthma and other atopic conditions. Therefore, FeNO does not contribute to the detection of asthma in the community.

CLINICAL IMPLICATION

FeNO is not a valuable tool for the detection of asthma in the community as it is confounded by other atopic conditions.

Are exhaled breath condensates useful in monitoring asthma?

Exhaled breath condensate (EBC) has emerged as a novel noninvasive technique for assessment of airway inflammation, and it also provides useful information on the airway lining fluid composition. Examples of markers that can be identified in the EBC of patients with asthma include pH, eicosanoids, nitrogen oxides and related products, markers of oxidative stress, certain cytokines, chemokines, and growth factors. There is some evidence that certain markers in EBC differ between patients with asthma and controls, and some markers may correlate with asthma severity and lung function, but there are many methodologic pitfalls with EBC assessment that limit its clinical applicability at present. More studies are needed before this technique can be recommended for clinical use.

T-helper type 2 polarization among asthmatics during and following pregnancy

BACKGROUND

Asthma is the most common medical condition during pregnancy. While increased production of T helper cytokines has been reported to occur in both asthma and pregnancy, the effect of T-helper type 2 (Th2) polarization on asthma symptoms during pregnancy has not been well-characterized.

OBJECTIVE

We hypothesized that systemic Th2 cytokine and chemokine polarization occurs among asthmatics to a greater extent during their pregnancy, and is associated with more severe asthma and increased Th2 polarization in the newborn.

METHODS

Fifty-six pregnant asthmatics were recruited from prenatal clinics affiliated with New York Presbyterian Hospital. Systemic production of interleukin-4, interferon-gamma, eotaxin and IP10 were measured by intracytoplasmic staining or ELISA at recruitment, peripartum and post-partum, and in the cord blood. The frequency of asthma symptoms was measured by questionnaires and compared with Th biomarkers.

RESULTS

The chemokine ratio (IP10/eotaxin) declined over the course of pregnancy (from 3.3 +/- 1.3 to 1.4 +/- 0.2, P = 0.016), but IP10 and eotaxin increased post-partum. The decrease in the chemokine ratio was associated with more frequent asthma symptoms. A non-significant trend towards decreased interferon-gamma and increased interleukin-4 production was detected. Cord blood eotaxin levels correlated with maternal levels (r = 0.35, P = 0.03). Other peripartum biomarkers were not associated with Th2 polarization nor with subsequent respiratory symptoms in the newborn.

CONCLUSION

IP10/eotaxin declined over the course of pregnancy and was associated with worse asthma symptoms. Alterations of Th1/Th2 chemokine balance during pregnancy may identify women prone to more severe asthma during pregnancy.

Exhaled biomarkers

Assessing airway and lung inflammation is important for investigating the underlying mechanisms of asthma and COPD. Yet these cannot be measured directly in clinical research and practice because of the difficulties in monitoring inflammation. Noninvasive monitoring may assist in early recognition of asthma and COPD, assessment of its severity, and response to treatment, especially during disease exacerbations. There is increasing evidence that breath analysis may have an important place in clinical management of asthma and COPD. The article reviews the role of current noninvasive measurements of exhaled gases, such as nitric oxide (NO), inflammatory markers in exhaled breath condensate (EBC), and exhaled breath temperature, as well as novel methods in monitoring and management of asthma and COPD.

Exhaled nitric oxide levels are not correlated with eczema severity in Chinese children with atopic dermatitis

Asthma is a common atopic disease associated with atopic dermatitis (AD) and allergic rhinitis (AR). Exhaled nitric oxide level (eNO) has been found to be an interesting noninvasive marker of disease severity in children with asthma. However, it is uncertain if eNO may be confounded by any coexisting AD or AR. In this study, eNO in Chinese children with moderate-to-severe AD and no asthma symptoms (n = 53) was measured online by a chemiluminescence analyzer. Severity of AD was assessed using the objective SCORing-Atopic-Dermatitis score and coexisting allergic rhinitis with the Allergic-Rhinitis-Score (ARS). Patients with active symptoms of asthma or inhaled/intranasal corticosteroids were excluded. There was no difference in eNO between genders and no correlation between eNO and AD severity regardless of ARS or bronchial reactivity status. ENO appears to be a noninvasive marker whose level is independent of the two atopic diseases of AD and AR in children old enough to perform exhalation maneuver.

CDLQI, SCORAD and NESS: are they correlated?

BACKGROUND

Quality of life (QOL) and clinical severity scores are important parameters in the evaluation of distress experienced by children with atopic dermatitis (AD). The SCORing Atopic Dermatitis (SCOARD) is a widely used clinical score for assessing AD symptomatology over the preceding 3 days and the Nottingham Eczema Severity Score (NESS) is another score useful for AD symptoms over the preceding 12 months.

OBJECTIVE

We evaluated if these parameters are correlated with QOL in children with AD.

PATIENTS/METHODS

We assessed quality of life, clinical scores, total IgE and eosinophil count in peripheral blood in AD patients at our paediatric dermatology clinic over a 14-month period.

RESULTS

Eighty AD patients (42 males and 38 females; mean [SD] age 11.7 [3.7] years) were recruited. The median (interquartile range, IQR) IgE, eosinophil counts and eosinophil percentage were 2988 (1069-7847) kIU/L; 0.6 (0.4-0.9) x 10(-9)/L; and 9 (6-12)%, respectively. Quality of life as measured with CDLQI (The Children's Dermatology Life Quality Index) generally did not correlate well with both the acute and chronic AD severity scores (objective SCORAD and total CDQLI, rho = 0.17, p > 0.05; total NESS and total CDQLI, rho = 0.29, p < 0.05). Factor analysis further confirmed that the objective indicators (serum total IgE, eosinophil count and objective SCORAD), self-reported scores (NESS and subjective SCORAD) and CDLQI were separate dimensions in the assessment of AD in children.

CONCLUSION

Quality of life, disease severity scores and laboratory atopic markers represent different domains in AD assessment. They do not necessarily correlate well with each other and all three aspects must be individually evaluated to assess the well-being of these patients.