Markers Of Atopy Research Articles

Exhaled nitric oxide: Not associated with asthma, symptoms, or spirometry in children with sickle cell anemia

The significance of fractional exhaled nitric oxide (Feno) levels in children with sickle cell anemia (SCA) is unclear, but increased levels can be associated with features of asthma and thus increased morbidity. We sought to determine factors associated with Feno and whether Feno levels are associated with increased rates of acute chest syndrome (ACS) and pain. All participants had SCA, were part of the prospective observational Sleep and Asthma Cohort study, and had the following assessments: Feno levels, spirometry, blood samples analyzed for hemoglobin, white blood cell counts, eosinophil counts and total serum IgE levels, questionnaires about child medical and family history, and review of medical records. The analytic sample included 131 children with SCA (median age, 11.2years; age range, 6-18years) followed for a mean of 16.2years, including a mean of 5.1years after baseline Feno data measurements. In multivariable analyses higher Feno levels were associated with ln(IgE) levels (P<.001) and the highest quartile of peripheral eosinophil counts (P=.03) but not wheezing symptoms, baseline spirometric indices, or response to bronchodilator. Multivariable analyses identified that the incident rate of ACS was associated with ln(Feno) levels (P=.03), as well as male sex (P=.025), wheezing causing shortness of breath (P=.002), and ACS at less than 4years of age (P<.001). Feno levels were not associated with future pain episodes. Steady-state Feno levels were not associated with an asthma diagnosis, wheezing symptoms, lung function measures, or prior sickle cell morbidity but were associated with markers of atopy and increased risk of future ACS events.

The prevalence of allergic rhinitis and atopic markers in obstructive sleep apnea

Allergic rhinitis (AR) related inflammation might worsen the severity of obstructive sleep apnea (OSA), however, the relationship between the two disorders remains controversial. Our aim was to determine the prevalence of AR and atopic markers in OSA. This cross-sectional study recruited participants with sleep-related complaints referred to a sleep center from February 2013 to June 2014. The diagnosis of OSA was based on the Berlin questionnaire (BQ) followed by confirmatory polysomnography (PSG). The diagnosis of AR was made via focused history and clinical examination and was confirmed by measuring atopic markers. OSA was diagnosed in 97 out of 157 adults attending the sleep clinic (61.8%). There was a high prevalence of AR (52.6%) among OSA individuals. This was not significantly different from the frequency in the non-OSA individuals (p=0.5). Elevated total immunoglobulin E (IgE; >100K/μL), eosinophil count, and positive Phadiatop tests were found in individuals with OSA to be 37.1%, 11.3%, and 41.2%, respectively. Individuals without OSA have shown similar percentages. In our cohort, there was no significant difference in frequency of AR and atopy among participants with OSA compared to those without OSA.

Vitamin D and Allergy

After the modern vitamin D hypothesis firstly suggested in 1999 for the allergy pandemic, numerous conditions have been thought to be associated with vitamin D deficiency such as allergy, autoimmunity and neoplasm. Consistently, previous observational studies have linked lower vitamin D status to increased markers of atopy and allergic diseases e.g. atopic dermatitis, anaphylaxis and food allergy. Vitamin D is a “hormone” having important immunomodulatory and immunoregulatory properties. In vitamin D deficient conditions, disrupted mucosal and skin complex integrity and intercurrent infections may act synergistically with allergenic exposure to amplify sensitization risk. There has been emerging data to show that vitamin D can enhance the anti-inflammatory effects of glucocorticoids and potentially be used as adjuvant therapy in steroid-resistant severe asthma. And recent in vivo data suggest that vitamin D supplementation reduce the severity of eczema and allergic rhinitis as well as urticaria symptoms. However, there is presently inadequate evidence to support daily vitamin D supplementation in the prevention and/or treatment of allergic diseases in infants, children and adolescents.

Reversible airway obstruction in cystic fibrosis: Common, but not associated with characteristics of asthma

BackgroundAs asthma-like symptoms are common in CF, we evaluated reversible airway obstruction and associated characteristics. MethodsRetrospective analysis of charts including spirometry and bronchodilator response. ResultsOf 190 CF patients (103 at Schneider's, 87 at Hadassah), aged 14.4 (4–76) years, median (range), 39% had reversible obstruction (ΔFEV1% predicted ≥12%), associated with younger age (p=0.01) and severe genotype (p=0.02). There was no association with family history of asthma, serum IgE, blood eosinophils, pancreatic status, FEV1<40% predicted, Aspergillus or pseudomonas infection. Of patients with reversible obstruction, 74% were on bronchodilator and 68% on inhaled corticosteroid therapy but 54% and 57% respectively receiving these therapies did not have reversible obstruction. ConclusionsReversible airway obstruction is common in CF, more frequent in younger patients and with severe genotype, with no correlation to markers of atopy or CF clinical severity. Bronchodilator and inhaled corticosteroid therapies are commonly prescribed even without reversible obstruction.

Clinical correlates of lung ventilation defects in asthmatic children

Lung ventilation defects identified by using hyperpolarized 3-helium gas ((3)He) lung magnetic resonance imaging (MRI) are prevalent in asthmatic patients, but the clinical importance of ventilation defects is poorly understood. We sought to correlate the lung defect volume quantified by using (3)He MRI with clinical features in children with mild and severe asthma. Thirty-one children with asthma (median age, 10 years; age range, 3-17 years) underwent detailed characterization and (3)He lung MRI. Quantification of the (3)He signal defined ventilation defect and hypoventilated, ventilated, and well-ventilated volumes. The ventilation defect to total lung volume fraction ranged from 0.1% to 11.6%. Children with ventilation defect percentages in the upper tercile were more likely to have severe asthma than children in the lower terciles (P = .005). The ventilation defect percentage correlated (P < .05 for all) positively with the inhaled corticosteroid dose, total number of controller medications, and total blood eosinophil counts and negatively with the Asthma Control Test score, FEV1 (percent predicted), FEV1/forced vital capacity ratio (percent predicted), and forced expiratory flow rate from 25% to 75% of expired volume (percent predicted). The lung defect volume percentage measured by using (3)He MRI correlates with several clinical features of asthma, including severity, symptom score, medication requirement, airway physiology, and atopic markers.

Bronchial asthma and hypovitaminosis D in Saudi children.

BackgroundAsthma, a common lung disease in children, is caused by excessive immune responses to environmental antigens.ObjectiveGiven the immuno-modulatory properties of vitamin D, the aim of the current study was to investigate the relationship between vitamin D levels and markers of asthma severity.MethodsThis was investigated in a 70 Saudi children with and without asthma and were recruited from the King Abdul Aziz University Hospital, Jeddah, Saudi Arabia, over the period of 11 months (May 2011-April 2012). Childhood asthma control test instrument was employed to assess the level of asthma control among asthmatic patients. Anthropometric measurements were taken and interviewer-administrated questionnaire was completed for all study participants. Pulmonary function test was performed by recording changes in the peak expiratory flow. Venous blood samples were withdrawn for measurements of vitamin D, bone profile, cytokines profile (interleukin-10, tumor necrosis factor-alpha, platelets derived growth factor), and atopy markers (IgE and eosinophil count).ResultsHypovitaminosis D is highly prevalent among asthmatic children with highly significant increase in several markers of allergy and asthma severity as compared with healthy control children. Significant correlations between several inflammatory and immunological markers and vitamin D levels were also found. Finally, lower 25-hydroxyvitamin D levels were associated with a higher asthma prevalence in multivariable analysis.ConclusionOur study showed that hypovitaminosis D is highly prevalent in the whole population in addition to a highly significant increase in several markers of allergy and asthma severity among asthmatic children as compared with healthy control children.

Exposure to 'farming' and objective markers of atopy: a systematic review and meta-analysis.

There is growing interest in the 'farm effect' on the spectrum of allergy. Evidence concerning the farm effect on asthma, eczema, and allergic rhinitis has been systematically synthesized, but without a specific focus on objective markers of sensitization. This focus is important, as farm exposures may be related to allergy but not to non-allergic phenotypes of disease. We aimed to systematically review and meta-analyse literature that has investigated associations between farm exposure at any age and objective measures of atopy, that is serum IgE or skin prick tests results. Using predefined inclusion and exclusion criteria, we identified 29 articles for review. IgE levels were measured in either childhood or adulthood by eighteen studies, while skin prick testing was performed in sixteen studies. Newcastle-Ottawa Scale quality assessments indicated that the majority of these studies demonstrated a representative sample of selected participants. Due to significant heterogeneity in study measures and methodology between studies, only few were meta-analysed. This meta-analysis showed a significant protective effect of farm exposure before 1year of life on allergic sensitization (OR=0.60 [0.52-0.70]). Farm exposure during childhood was also associated with a reduced risk of sensitization to cat or timothy (OR=0.60 [0.51-0.70]; OR=0.46 [0.41-0.51]). Studies investigating the effect of farm exposure in adult life could not be meta-analysed, and their results were inconsistent. Insufficient studies investigated food sensitization as an outcome to allow synthesis. The majority of studies included in this review investigated childhood farm exposure, finding evidence to support a protective childhood 'farm effect' against subsequent atopy. There is inconsistent evidence on the association between farm exposure in adulthood and allergic sensitization. Further studies are needed to tease out the exact exposures and timing associated with farming environments that protect against allergic disease.

Correlation between serum 25-hydroxyvitamin D3and the severity of atopic dermatitis in children with allergic or nonallergenic sensitization

Purpose: The aim of this study was to assess the relationship between serum 25-hydroxyvitamin D3 levels and the severity of atopic dermatitis (AD), markers of atopy (total IgE, total eosinophil count, and eosinophil cationic protein) in AD children according to allergen sensitization. Methods: This cross-sectional study was carried out on 160 AD patients aged 1 to 18 years between March 2012 and August 2014. The AD patients (AD group) were subdivided into 2 categories according to the results of the allergic skin prick and Unicap tests: the allergic and nonallergic AD groups. We compared 25-hydroxyvitamin D3 levels between the AD and control groups. We also investigated relationships between serum 25-hydroxyvitamin D3 levels, the severity of AD, and markers of AD (total IgE, total eosinophil count, and eosinophil cationic protein) in the allergic and nonallergic AD groups. Results: The average 25-hydroxyvitamin D3 levels were 30.6±11.7 and 23.7±10.0 ng/mL, respectively, in the control and AD groups (P<0.001). The average 25-hydroxyvitamin D3 levels were 19.7±8.6 and 27.5±9.8 ng/mL, respectively, in the allergic and nonallergic AD groups, with clinical implications (P<0.001). The 25-hydroxyvitamin D3 levels were not significantly associated with SCORing Atopic Dermatitis index in the allergic (P=0.004, r=.0.092) or nonallergic (P=0.610, r=.0.58) AD groups. The 25-hydroxyvitamin D3 levels were not significantly associated with the aforementioned markers of atopy in the AD group. Conclusion: These results suggest that 25-hydroxyvitamin D3 may play a role in the pathogenesis of AD.(Allergy Asthma Respir Dis 2015;3:213-218)

The impact of anemia and hemoglobin level as a risk factor for asthma and allergic diseases

Aim: To determine the association between anemia and asthma among children as case-control and also investigate the effect of hemoglobin (Hb) on asthma and atopy markers. Settings: The case-control study was performed during a period between March 2012 and October 2013, on asthmatics and controls (<14 years) at Pediatric Allergy-Immunology Clinics and Primary Health Care Clinics, Qatar. Subjects and Methods: A total of 520 cases and 520 controls matched by age, gender, and ethnicity. Sociodemographic and clinical data were collected through physician diagnosis and questionnaire. Their health status was assessed by past or present clinical manifestations, family history, physical examination, body mass index (BMI), anemia, Hb level, calcium, and phosphorus. Results: About 56.3% of asthmatic and 51.9% of controls were males and 43.7% of asthmatic and 48.1% of controls were females. The mean age (± standard deviation, in years) for asthmatic versus controls was 9.3 ± 3.28 versus 10.2 ± 3.38. Anemia was more prevalent in asthmatics than controls. Lower Hb levels were associated with more allergic disease and elevated serum IgE. The study revealed that Hb level, iron and ferritin deficiencies were considerably higher in asthmatic children compared to healthy children. There was a significant difference found in the mean values of Hb levels between asthmatic (10.58 ± 3.05 g/dL) and control children (11.75 ± 3.10) (P = 0.006). Besides, mean IgE was statistically significantly higher in asthmatic compared to control children (P < 0.001). There was a significant correlation between Hb level and total IgE in asthmatic compared to controls (r = 0.295 vs. r = 0.268, P = 0.001). The analysis revealed that the predictors for development of asthma in children were serum iron deficiency (P < 0.001), phosphorus (P < 0.001), parental consanguinity (P = 0.046), breastfeeding < 6 months (P < 0.001), BMI (P = 0.005), less physical activity (P < 0.001), family history of asthma (P = 0.028), and ferritin (P < 0.001). White blood cell count (P < 0.001), serum IgE level (P < 0.001), and serum calcium level (P < 0.001) were considered as the main risk factors after adjusting for age, gender, and other variables. Conclusion: The study findings showed a high prevalence of iron deficiency among children with asthma and allergic diseases. Serum Hb levels were lower in asthma, allergic rhinitis, and atopic dermatitis children. Hb level and anemia were strong contributors for asthma and allergic diseases.

Natural history of allergic sensitization in infants with early-onset atopic dermatitis: results from ORCA Study.

Early-onset atopic dermatitis (AD) is a particular phenotype that may convey a risk of developing multiple sensitizations to allergens but little is known about the pathway of sensitization. The aims of this study were to describe the natural history of sensitization to allergens for this phenotype and to identify the most predictive marker associated with the risk of developing sensitization to inhaled allergens in a well-selected cohort of infants with AD. Infants with active AD were enrolled and prospectively explored for biological markers of atopy every year until the age of 6 yr. Allergic sensitization was defined as the presence of positive specific IgEs to allergens and multiple sensitizations as being sensitized to ≥2 allergens. Elevated blood eosinophilia was defined as an eosinophil blood count ≥470 eosinophils/mm(3) and elevated total IgE as a serum IgE level ≥45 kU/l. Two hundred and twenty-nine infants were included. Elevated blood eosinophilia was observed at baseline in 60 children (26.2%) and elevated total IgE in 85 (37.1%). When elevated at baseline, eosinophilia and IgE levels remained significantly higher during the follow-up period. Sensitization to food allergens decreased from 58% to 34%, whereas sensitization to inhaled allergens increased over time from 17% to 67%. Initial multiple sensitizations to food allergens were the most predictive factor for the risk of developing sensitization to inhaled allergens at 6 yr (OR 3.72 [1.68-8.30] p < 0.001). In the early-onset AD phenotype, multiple sensitization to food allergens conveys a higher risk of sensitization to inhaled allergens than single sensitization.

Determinants of allergic rhinitis in young children with asthma.

BackgroundIn the preschool period, allergic rhinitis (AR) is infrequent and thus under-diagnosed. However, recent works have highlighted the occurrence of AR in toddlers although the causes of AR in this young population remain unknown. The objective of this study was to identify determinants of AR in young children with asthma.MethodsWe carried out a case-control study of 227 children with active asthma and enrolled in the Trousseau Asthma Program. AR and other allergic diseases (asthma, food allergy and eczema) were diagnosed by medical doctors using standardized questionnaires. Parental history of AR and asthma, biological markers of atopy (total IgE, blood eosinophilia, allergic sensitization towards food and aeroallergens) and environmental parameters were also collected.ResultsForty one of the children (18.1%) had AR. By univariate logistic regression analysis, AR was mainly associated with peanut sensitization (OR = 6.75; p = 0.002); food allergy (OR = 4.31; p = 0.026); mold exposure (OR = 3.81 p<0.01) and parental history of AR (OR = 1.42; p = 0.046). Due to the strong link between food allergy and peanut sensitization three models of multivariate logistic regression were performed and confirmed that AR is associated with peanut sensitization but also food allergy and mold exposure. A random forest analysis was also performed to explain AR. The results reinforced the logistic analysis that peanut sensitization and mold exposure were the principal determinants of AR.Conclusions & Clinical RelevanceThese results stress the importance of investigating AR in young children with asthma to potentially diagnose a particularly severe allergic asthmatic phenotype. Moreover, these data evoke the hypothesis that peanut could be an aeroallergen.

Association between body composition and subsequent childhood asthma and wheeze outcomes in the Southampton Women's Survey cohort study

BackgroundObesity is associated with adult asthma, notably non-atopic asthma. The association between obesity and childhood asthma is unclear and complicated by changes in body composition during growth. We aimed to determine whether and how body composition and change in body composition are associated with childhood asthma, wheeze, and atopic outcomes. MethodsParticipants were 940 children born between February, 2000, and June, 2003, to women recruited within the Southampton Women's Survey. Body composition was characterised with body-mass index (BMI) at 3 years and 6 years of age, standardised for age and sex; lean and fat mass measured at 4 years and 6 years of age with dual energy X-ray absorptiometry (DEXA) scanning; and serial measures of subscapular skinfold thickness. Relative risks were calculated with Poisson regression for questionnaire-determined asthma and wheeze at age 6 years. Wheeze was defined as atopic or non-atopic according to skin prick testing. Spirometry, bronchial hyper-responsiveness (BHR), and fractional exhaled nitric oxide (FeNO) were assessed at 6 years of age. Potential maternal and socioeconomic confounders were adjusted for and exposure variables combined in multivariable models. Written informed parental consent was obtained for each participant. The study was approved by the Southampton and South West Hampshire Local Research Ethics Committee. FindingsBMI at 6 years of age was not associated with asthma, atopy, any wheeze phenotype, or measure of lung function. Higher BMI at age 3 years was associated with greater BHR at age 6 (p=0·032) and with lower forced expiratory volume in the first second of expiration corrected for lung size by dividing by forced vital capacity (FEV1/FVC) (p=0·013). Although a conditional increase in subscapular skinfold thickness between 1 and 2 years was associated with asthma at age 6 years (relative risk 1·27, 95% CI 1·07–1·51), a decrease in subscapular skinfold thickness between 2 and 3 years was associated with increased risks of asthma (0·73, 0·55–0·96), wheeze, atopy, and atopic wheeze at age 6 years and with greater FeNO. InterpretationCurrent BMI at 6 years was not associated with asthma symptoms or impaired lung function in this cohort of children at age 6 years, although a higher BMI at age 3 years was associated with increased BHR and reduced FEV1/FVC at age 6 years. More rapid adiposity gain between ages 1 and 2 years was associated with increased asthma risk; although this finding might be an adverse effect of increased adiposity on respiratory development, rapid postnatal adiposity gain might be catch-up growth and might be a marker for adverse in-utero factors. By contrast, lower adiposity gain between 2 and 3 years was associated with asthma and markers of atopy and eosinophilic airway inflammation, suggesting that factors associated with poor weight gain in this period, such as recurrent respiratory infection, might predispose to atopic sensitisation. FundingMedical Research Council, British Heart Foundation, Food Standards Agency, Arthritis Research UK, National Osteoporosis Society, International Osteoporosis Foundation, Cohen Trust, NIHR Southampton Biomedical Research Centre, NIHR Oxford Biomedical Research Unit, British Lung Foundation.

Biomarkers of eosinophilic inflammation in asthma

Eosinophils are mediators of allergic inflammation and are implicated in the pathogenesis of numerous conditions including asthma, parasitic infections, neoplasms, hyper-eosinophilic syndromes, vasculitic disorders, and organ-specific conditions. Assessing eosinophilic inflammation is therefore important in establishing a diagnosis, in monitoring and assessing response to treatment, and in testing novel therapeutics. Clinical markers of atopy and eosinophilic inflammation include indirect tests such as lung function, exhaled breath condensate analysis, fractional exhaled nitric oxide, serum immunoglobulin E levels and serum periostin. Direct measures, which quantify but do not anatomically localise inflammation include blood eosinophil counts, serum or plasma eosinophil cationic protein and sputum eosinophil levels. Cytology from bronchoalveolar lavage and histology from endobronchial and transbronchial biopsies are better at localising inflammation but are more invasive. Novel approaches using radiolabelled eosinophils with single-photon emission computed tomography, offer the prospect of non-invasive methods to localise eosinophilic inflammation.

Association of Aeroallergen Sensitization with Asthma Severity and Treatment.

Relationship between atopy and asthma is complex. Studies evaluating association between markers of atopy with asthma severity or lung function tests have failed to yield consistent results. A prospective cohort study was done at the Pediatric Chest Clinic at tertiary care university hospital, Delhi, India. Children with physician diagnosed, moderate to severe persistent asthma, between 5 and 15 years of age, were enrolled from May 2007 to June 2009. Sensitization to aeroallergens was assessed by the skin prick test using 12 common aeroallergens. Asthma was managed according to the National Asthma Education and Prevention Program-Expert Panel Report 3 guidelines and children were followed up as a cohort every 2 months for 6 months. Correlation between aeroallergen sensitization, atopic markers with asthma severity, and treatment outcome was studied. Seventy-eight (57 boys) patients with mean age of 109±27 months were subjected to the skin prick test. Forty-nine (62.8%) children were sensitized to at least one aeroallergen. Common aeroallergens to which children were sensitized: cockroach (37%), rice dust (31%), mosquito (29%), housefly (29%). Sensitized patients had a higher rate of breathlessness, seasonal symptoms, and atopic dermatitis than those who were nonsensitized, (P<0.05). Children with high absolute eosinophil count had decreased spirometry parameters after 6 month of follow up, (P=0.04). Sensitization rates were independently associated with children having breathlessness (P=0.04) and seasonal symptoms (P=0.01). No significant association was found between sensitization, asthma severity, and treatment outcome. Aeroallergen sensitization was found in two-third patients. The most common aeroallergens were insects and rice dust. Sensitization was neither related to asthma severity nor to asthma control.

Exhaled nitric oxide is related to atopy, but not asthma in adolescents with bronchiolitis in infancy

BackgroundThe fraction of exhaled nitric oxide (FeNO) has been suggested as a non-invasive marker of eosinophilic inflammation in asthma, but lately rather as a biomarker of atopy than of asthma itself. Asthma after bronchiolitis is common up to early adolescence, but the inflammation and pathophysiology may differ from other phenotypes of childhood asthma. We aimed to assess if FeNO was different in children with former hospitalization for bronchiolitis and a control group, and to explore whether the role of FeNO as a marker of asthma, atopy or bronchial hyperresponsiveness (BHR) differed between these two groups of children.MethodsThe study included 108 of 131 children (82%) hospitalized for bronchiolitis in 1997–98, of whom 82 (76%) had tested positive for Respiratory syncytial virus, and 90 age matched controls. The follow-up took place in 2008–2009 at 11 years of age. The children answered an ISAAC questionnaire regarding respiratory symptoms and skin prick tests, spirometry, methacholine provocation test and measurement of FeNO were performed.ResultsAnalysed by ANOVA, FeNO levels did not differ between the post-bronchiolitis and control groups (p = 0.214). By multivariate regression analyses, atopy, height (p < 0.001 for both) and BHR (p = 0.034), but not asthma (p = 0.805) or hospitalization for bronchiolitis (p = 0.359), were associated with FeNO in the post-bronchiolitis and control groups. The associations for atopy and BHR were similar in the post-bronchiolitis and in the control group.ConclusionFeNO did not differ between 11 year old children hospitalized for bronchiolitis and a control group. FeNO was associated with atopy, but not with asthma in both groups.

Dry night cough as a marker of allergy in preschool children: the PARIS birth cohort

Early detection of children at risk for developing allergy is an important challenge. Our first analyses in infants from the Pollution and Asthma Risk: an Infant Study (PARIS) birth cohort suggested that dry night cough was associated with parental-reported allergic disorders. The aim of the present study was to refine this finding by investigating the time course of dry night cough from birth to age 4yr in relation to blood markers of atopy and allergic morbidity. Health outcomes were regularly assessed by parental self-administered questionnaires. Blood markers of atopy were measured at age 18months. Children with similar patterns of dry night cough over the first 4yr of life were grouped together using k-means clustering. Associations with atopy/allergy were studied using multinomial logistic regression. Three trajectories of dry night cough were identified in 1869 children. Besides the never/infrequent pattern (72.4%), the transient pattern (8.8%) was composed of children who coughed in the first year and recovered by age 4yr, while the rising pattern (18.8%) included all symptomatic children at age 4yr, whether they were persistent or late coughers. Compared with the never/infrequent pattern, the rising pattern was significantly associated with elevated total immunoglobulin E (IgE) level (odds ratio [OR]=1.70, 95% confidence interval [CI]=1.21-2.39) and inhalant allergens sensitization (OR=2.66, 95% CI=1.26-5.61) at age 18months, and with doctor-diagnosed allergic diseases over the first 4yr such as hay fever (OR=2.52, 95% CI=1.49-4.26) and eczema (OR=1.29, 95% CI=1.00-1.66). This study provides evidence that persistent/late dry night cough may indicate allergy in preschool children.

Vitamin D Insufficiency and Asthma Severity in Adults From Costa Rica

PurposeNon-classical actions of vitamin D as a cytokine are related to the immunopathology of asthma. Few studies have examined vitamin D levels and asthma severity in adults. The aim of this research was to assess the relationship between vitamin D levels, atopy markers, pulmonary function, and asthma severity.MethodsWe analyzed 25-hydroxyvitamin D levels in serum collected from 121 asthmatic adults from Costa Rica to investigate the association between vitamin D levels (categorized as sufficient, ≥30 ng/mL, or insufficient, <30 ng/mL), allergic rhinitis, total IgE and peripheral blood eosinophils (as markers of atopy), asthma severity, baseline forced expiratory volume in 1 second (FEV1), and forced vital capacity (FVC). Univariate and multivariate analyses were performed to assess these relationships.ResultsWhen the population was stratified by vitamin D status, 91% of asthmatic patients with vitamin D levels below 20 ng/mL (n=36) and 74% of patients with vitamin D levels between 20 and 30 ng/mL (n=73) had severe asthma versus 50% of those with vitamin D sufficiency (n=12; P=0.02). Vitamin D insufficiency was associated with a higher risk of severe asthma (odds ratio [OR], 5.04; 95% Confidence interval [CI], 1.23-20.72; P=0.02). High vitamin D levels were associated with a lower risk of hospitalization or emergency department visit during the last year (OR, 0.90; 95% CI, 0.84-0.98; P=0.04). Although there appeared to be a direct relationship between vitamin D levels and FEV1 (regression coefficient=0.48; r2=0.03), it did not reach statistical significance (P=0.07).ConclusionsOur findings suggest that vitamin D insufficiency is common among our cohort of asthmatic adults. Lower vitamin D levels are associated with asthma severity.

Cord IgE and ECP levels of Malay neonates

BackgroundCord IgE and ECP levels are major atopic markers implicated in early childhood allergy development. Most epidemiological studies to date have not utilised current technology to establish baseline cord IgE levels, further aggravated by lack of data in this region. This study also attempts to identify a relationship between cord IgE and ECP levels as a mean to improve sensitivity for early prediction of atopy. MethodsA total of 3183 cord blood IgE including 44 cord ECP samples of term neonates from Malay parentage were recruited. Total IgE and ECP levels were determined by ImmunoCAP and fluoroimmunoenzymatic, respectively. ResultsCord IgE geometric mean was 0.15kU/L. Males had higher IgE geometric mean than females (0.17 vs. 0.13). IgE values between 17 pair of twins was not significant (p=0.169). Frequency of males (29.9%) in >0.9kU/L IgE category was higher than females (26.1%). In the <0.35kU/L category, females had a higher frequency (44.8%) than males (39.1%). Males had significantly (p=0.023) higher IgE level than females. November and February had the highest mean and median cord IgE level whereas October and December were the lowest, respectively. IgE level across months was not significant (p=0.234). Cord ECP mean was 5.21g/L and median was 3.75μg/L. There was no significant correlation (p=0.513; r=-0.101) between cord blood ECP and IgE levels. ConclusionCord blood IgE level of Malay male neonates was significantly higher than females. These results do not support cord ECP as plausible adjunct parameter to IgE for early atopic detection.

AB 81. Comparison of validity of methacholine and mannitol bronchial challenges in asthma diagnosis

Background The purpose of this study was to demonstrate the diagnostic validity of the two bronchial challenges and their correlation with symptoms, atopy and inflammatory markers.

Food Allergy and the Development of Asthma Symptoms

Allergies are multifactorial diseases the onset of which depends also on genetic and environmental factors in early life. Thus, environmental factors can affect the immune response and modify lung development, thereby leading to asthma. The role of the factors used to date to predict asthma development is modest, and clinical criteria should always be considered in association with familiarity for atopy. The aim of this study is to evaluate the risk of asthma in a population with positive skin prick test (SPT) (which is a reliable marker of atopy) to food allergens, regardless of clinical manifestations in the early years of life. The cohort of children enrolled in our study who had a positive SPT to food in the first three years of life had a prevalence of asthma after 7-14 years, double that of the general pediatric population. This prevalence increased significantly in patients with SPT positivity for food and inhalant allergens. We identified a correlation between the sensitization profile in children under the age of 36 months and the development of asthma during a period of 7-14 years. This study confirms that early sensitization is an important risk factor for the development of asthma, particularly in association with sensitization to inhalants, and that the persistence of food sensitization in school-age children and adolescents is associated to more severe asthma.