The relationship among markers of allergy, asthma, allergic rhinitis, and eczemain Costa Rica

The association between allergy markers and asthma and allergic rhinitis is stronger in countries with a Western lifestyle than in rural areas of Africa and Asia. We examined the relationship among allergy markers, asthma, rhinitis, and eczema in a case-control study of 198 schoolchildren, 10–13 years of age, living in Costa Rica, a Latin American country. The geometric mean total serum immunoglobulin E (IgE) level in subjects with and without asthma was 465.0 and 143.0 IU/ml, respectively (difference = 322 IU/ml, 95% CI = 141.8–616.1 IU/ml, p < 0.001), and that in subjects with and without allergic rhinitis was 442.5 and 144.3 IU/ml, respectively (difference = 298.2 IU/ml, 95% CI = 125.7–581.0 IU/ml, p < 0.001). After adjusting for age, gender, and skin test reactivity to allergens, we found a linear relationship between serum total IgE level and the log odds ratio (OR) of having asthma. In a multivariate analysis, there was a linear relationship between skin test reactivity to allergens and the log OR of having allergic rhinitis. The OR of having allergic rhinitis was almost three times higher in children who had four positive skin tests than in non-reactors. Skin test reactivity to greater than five aeroallergens was an independent predictor of eczema in a multivariate analysis (OR = 3.1, 95% CI = 1.1–8.4). Although the geometric mean total serum IgE levels of Costa Rican children with either asthma or allergic rhinitis are higher than those of children with asthma or allergic rhinitis in most industrialized countries, the relationship among markers of allergy, asthma, rhinitis, and eczema in Costa Rica is similar to that found in countries with a Western lifestyle and different from that found in rural areas of Asia and Africa.     

Atopic features in early childhood autism

BACKGROUND: Autism is a developmental disorder of unknown etiology. Sensitivity to dietary and environmental antigens has been considered in its pathogenesis. AIM: To examine immediate hypersensitivity in early childhood autism. METHODS: We investigated 30 autistic children (23 boys, seven girls 2-4 years old) for atopic history, serum IgG, IgA, IgM, IgE levels, and skin prick tests (SPT) with 12 common antigens. RESULTS: Nine/30 autistic children (30%) and 1/39 (2.5%) age-matched neurological controls from the same hospital had a family history suggestive of atopy (p<0.005). No patient in the autism and 28% in control group had symptoms of respiratory allergy (wheezing or asthma) (p<0.005), and 6/30 (20%) autistic vs. 7/39 (17%) control children had history suggesting other allergic disorders (p=ns). Eleven/23 (47.8%) autistic children had at least one positive skin test, similar to age-matched population controls. Serum IgG, IgA, and IgM levels were within age-appropriate limits. Serum IgE was elevated in four patients (13.3%). Specific IgE levels were negative in four cases with multiple SPT positivity. CONCLUSIONS: This study suggests allergic features based on history, skin tests, and serum IgE levels are not frequent in young autistic children despite family history. This discrepancy between predisposition and manifestation might imply immunological factors or environmental conditions.     

A matched patient-sibling study on the usage of paracetamol and the subsequent development of allergy and asthma

A number of studies have suggested that intake of paracetamol during pregnancy and during the first months of life is associated with an increased risk of childhood asthma. We aimed to determine the association between paracetamol usage during pregnancy and the first 6 months of life, and childhood allergy (i.e. positive skin prick tests), allergic asthma, and asthma, using a matched patient-sibling study comparing patients with allergic asthma with their healthy siblings without any symptoms of allergic diseases. Allergy in patients and their siblings was determined by skin prick tests. Children having at least one positive skin prick test were considered to be allergic. Intake of paracetamol was assessed by standardized, interviewer-administered, questionnaire. Nineteen pairs of allergic asthma patients vs. non-allergic siblings were compared to determine the risk factors for allergic asthma, while 15 pairs of allergic asthma patients vs. allergic siblings were compared to determine the risk factors for asthma. Moreover, 33 pairs of allergic asthma patients vs. non-asthmatic siblings (with and without allergy) were compared to determine the risk factors for asthma. In addition, 17 allergic siblings (without asthma) were compared with 19 non-allergic siblings (without asthma) to determine the risk factors for allergy. Usage of paracetamol during pregnancy was associated with allergic asthma (p = 0.03). Furthermore, usage of paracetamol between birth and 6 months of age, and between 4 and 6 months of age, was also found to be associated with non-allergic asthma (p = 0.008 and p = 0.03 respectively). Usage of paracetamol during pregnancy and during the early months of life may play a role in the development of allergic and non-allergic asthma in children. However, due to obvious ethical reasons, direct evidence for this association (i.e. a double-blind, prospective study) is not available.     

Development of specific immunoglobulin E in coughing toddlers: A medical records review of symptoms in general practice

The aim of this study was to study whether young children, originally immunoglobulin E (IgE) negative and who became sensitized to specific inhalation allergens, presented more frequently to their general practi‐tioner (GP) with other allergy‐ and asthma‐related symptoms than children who remained IgE negative. It was also investigated whether asthma was diagnosed more often in children who developed IgE to inhalant allergens. Coughing children, 1–5 years of age, visiting the participating GPs, were tested for IgE antibodies to mites, dogs, and cats by using radioallergosorbent testing (RAST). All IgE‐negative (RAST < 0.2 IU/ml) children were re‐tested after 2 years. The medical records of 162 children were reviewed on asthma‐ and allergy‐related symptoms and on prescribed medication. After 30 months, 27 of the 162 children (17%) had become IgE positive for one or more allergens. Most children (93%) had visited their GP for treatment of respiratory symptoms during this period. However, the children who had become IgE positive had visited their GP more often than the children who remained IgE negative. Differences in visits were seen for: shortness of breath (52% IgE‐positive vs. 19% IgE‐negative children, respectively), wheeze (37% vs. 17%), allergic rhinitis (33% vs. 16%), and pneumonia (22% vs. 8%), but not for coughing (89% vs. 88%). The IgE‐positive children were more frequently diagnosed by their GP as having asthma (48%) than were the IgE‐negative children (23%). In a multivariate analysis, indicators of becoming IgE positive were: a visit for shortness of breath (odds ratio [OR] = 6.9; 95% confidence interval [CI] = 2.1–23.1) and two or more visits for wheeze (OR = 6.0; 95% CI = 1.9–19.2), adjusted for breast‐feeding, age, and asthma or allergy in the family. The positive predictive value (PPV) of being IgE positive with a diagnosis of asthma was 90% (whereas the negative predictive value was 48.0%) for a child attending their GP for treatment of wheeze. For recurrent coughing (six or more visits) and shortness of breath, the PPVs were 73% and 71%, respectively. The development of sensitization to common inhalant allergens is associated with specific allergy and asthma‐related symptoms in young children. IgE‐positive children were more frequently diagnosed as having asthma by their GP. This implies that in general practice it is possible to detect children at high risk for developing allergic asthma early in life by their respiratory symptoms and by subsequent testing for specific IgE to inhalant allergens.     

Exhaled nitric oxide, total serum IgE and allergic sensitization in childhood asthma and allergic rhinitis

Exhaled nitric oxide (eNO) levels are correlated with several markers of atopy and inflammatory activity in the airways, but the relationship between eNO and total serum IgE has not been fully elucidated in the context of allergic sensitization. The aim of this study was to investigate the relationship between eNO, total serum IgE and allergic sensitization in childhood asthma and allergic rhinitis. eNO levels, lung function, skin prick tests and total serum IgE were determined in 109 children (mean age, 10.4 yr) with mild intermittent asthma and in 41 children (mean age, 10.1 yr) with allergic rhinitis; 25 healthy non-atopic children were recruited as controls. eNO levels (median) were significantly higher in patients with asthma (22.7 p.p.b.) and in those with allergic rhinitis (15.3 p.p.b.) than in healthy controls (5.9 p.p.b.). Children with allergic asthma had higher eNO levels than children with allergic rhinitis. A significant positive correlation was found between eNO and total serum IgE (asthma, r = 0.42, p < 0.0001; allergic rhinitis, r = 0.31, p < 0.01), and between eNO and the number of positive skin prick tests (asthma, r = 0.31, p < 0.0001; allergic rhinitis, r = 0.39, p < 0.01). eNO levels were better correlated with total IgE than with the number of positive skin prick tests. This correlation was independent of allergic sensitization. High total serum IgE represents a specific and predictive marker of eNO increase in children with asthma or allergic rhinitis. This finding adds further support to the hypothesis that increased serum IgE could be a marker itself of airway inflammation in patients with allergic disease.     

FcgammaRIIIa-V/F 158 polymorphism in Turkish children with asthma bronchiale and allergic rhinitis.

Fc receptors (FcR) play an important role in immune regulation. This might be linked to the variability in immune response, therefore relating to the pathogenesis of atopic diseases. The aim of the present study was to evaluate the FcgammaRIIIa gene polymorphism in Turkish children with asthma and allergic rhinitis. The study included 364 atopic children (184 bronchial asthma, 180 allergic rhinitis) and 234 healthy subjects as the control group, aged between 5 to 16 years. Patients were recruited from outpatient clinics of allergy and general pediatric care. Plasma IgE concentrations were measured by immunoassays and skin prick test was done in children with atopic diseases. The FcgammaRIIIa gene polymorphism was determined using the polymerase chain reaction method. Distribution of V158V genotype was significantly different among patient groups compared to controls (for asthmatic children OR: 5.33, 95% CI: 2.80-10.23, p < 0.001; for allergic rhinitis OR: 3.25, 95% CI: 1.75-6.07, p = 0.001). Distribution of 158 V allele was significantly different among asthmatic children (OR: 2.20, 95% CI: 1.65-2.92, p < 0.001) and allergic rhinitis patients (OR: 1.77, 95% CI: 1.32-2.35, p < 0.001) compared to healthy controls. Our study shows that the V158V genotype in FcgammaRIIIa gene polymorphism may be a genetic risk factor for the development of atopic diseases.     

High basophil allergen sensitivity (CD-sens) is associated with severe allergic asthma in children

Children with problematic severe asthma (PA) have persistent symptoms and/or severe exacerbations despite treatment with several drugs. Classification of asthma severity is currently based on level of treatment and assessment of asthma control, but objective biomarkers of asthma severity are needed. To investigate the clinical relevance of basophil allergen threshold sensitivity (CD-sens) as a measure of allergen sensitivity in a well-characterized cohort of children with different manifestations of persistent allergic asthma. Cat-allergic children (6-18 yr) with problematic severe asthma (n = 11) according to GINA were compared with eleven age-matched children with controlled, but persistent asthma (CA). The protocol included standardized questionnaires, asthma control test (ACT), spirometry, methacholine challenges, measurement of FE(NO,) IgE, cat IgE and IgG antibodies, and analysis of CD-sens (CD63-expression) by flow cytometry. The 11 cat-allergic children with PA had a significantly lower ACT score (p < 0.001), reduced FEV(1) (p = 0.04), and increased numbers of blood eosinophils (p = 0.03) compared with the 11 children with CA. The former exhibited a higher CD-sens to cat (p = 0.02). No significant differences were detected with respect to FE(NO) (p = 0.17), IgE (p = 0.84), cat IgE (p = 0.12), and the major cat-allergen rFel d 1 (p = 0.30). CD-sens significantly correlated with ACT (p = 0.002, r = -0.63) and FE(NO) (p = 0.01, r = 0.55). No significant differences between PA and CA were found regarding IgG antibodies to rFel d 1. Cat-allergic children with problematic severe asthma have higher sensitivity to cat allergen, as measured by CD-sens, compared with children with controlled asthma. This suggests that CD-sens could be used as an additional marker for identifying children with the most severe allergic asthma.     

Exercise-induced bronchocontriction, skin sensitivity, and serum IgE in children with eczema.

Forty-two children with eczema were studied for exercise-induced astham (EIA), skin sensitivity to prick testing, blood eosinophil count, and immunoglobulins. 29 had a fall in peak expiratory flow rate after exercise greater than 20% and of these, 23 had symptoms of wheezing. 13 of the eczematous children showed a fall of less than 20%. The children with EIA showed greater cutaneous sensitivity (p less than 0.001) and a higher total serum IgE (p less than 0.025). 3 of the group with a fall of less than 20% had allergic rhinitis with skin sensitivity to grass pollen. The remaining 10 had no clinical evidence of allergic disease, other than eczema and skin sensitivity, and total IgE fell within the normal range. It is suggested that in a proportion of chilren with eczema there is little evidence of reaginic allergy.     

Presentation of atopic disease in a large cohort of pediatric liver transplant recipients

Atopic disease occurs in solid organ transplant recipients with an increasingly recognized frequency. The time course for the development of these atopic diseases in liver transplantation has not been described. The objective was to characterize the atopic manifestations of children receiving chronic immunosuppression after orthotopic liver transplantation (OLT). Chart review and follow-up questionnaire were utilized for 176 OLT pediatric recipients at a single institution for manifestations of allergic disease. Atopic disease was present in 25 (14.2%) patients. Median age at transplant was 16 months with a median follow-up of 63 months. Food allergy and non-food related atopic symptoms presented at a median of 11.5 (IQR, 6-28) and 19 (IQR, 5-41) months post-transplantation, respectively. The median age at transplant of the non-atopic children was 72 months, higher than patients with atopy (p < 0.001). Food allergy and atopic skin disease symptoms were present in 40% and 56% of cases, respectively. Asthma, allergic rhinitis, or both were found in 66% of cases. The onset of symptoms of food allergy and eczema (median, 12 months post-transplantation) preceded symptoms of allergic rhinitis and asthma. (median of 27 and 30 months post-transplantation, respectively). Atopy occurs in ～14% of pediatric liver transplant recipients, with manifestations including food allergy, eczema, allergic rhinitis, and asthma.     

Genetic and environmental factors affecting the development of atopy through age 4 in children of atopic parents: a prospective randomized study of food allergen avoidance

The effect of food allergen avoidance, as well as other environmental and genetic factors, on the development of atopy were determined in this follow-up report of a prospective randomized controlled study of 288 infants of atopic parents, in which 78% were available for evaluation at age 4 years. The prophylactictreated group consisted of mothers who avoided cow milk. egg. and peanut during the last trimester of pregnancy and lactation and of infants who avoided cow milk until 1 year (casein hydrolysate supplementation prior to 1 year) and egg, peanut, and fish until after 2 years. The control group consisted of maternal/infant pairs who followed standard feeding practices. The cumulative prevalence of food allergy and food sensitization remained lower in the prophylactic treated group from 1 to 4 years of age. However, the period (current) prevalence of food allergy in both study groups was similar (about 5%) at 3 and 4 years. Such findings suggest that period prevalence may represent the more appropriate measure to assess the impact of intervention measures on the development of atopic disease at older ages. Prophylactic-treated children evidenced lower levels of IgG beta lacloglobulin (BLG) at 4 months and I and 2 years (p < 0.0001) and lower IgG ovalbumen/ovomucoid (OVA) levels only at 2 years (p < 0.001). Both groups evidenced similar prevalences of asthma, allergic rhinitis, and positive inhalant skin tests from birth to 4 years. Children with food allergy evidenced higher 4 year cumulative prevalences of allergic rhinitis and asthma (p < 0.05). Risk factors for atopic disease by age 4 years were shown by multivariate analysis (p < 0.05) to include (1) unrestricted diet and elevated cord blood IgE with food allergy, (2) male gender and lower paternal level of education with asthma, and (3) non-caucasian ethnicity and spring/summer birth with atopic dermatitis and allergic rhinitis. Serum IgE levels were not significantly different between groups at 3 and 4 years, despite their being a trend towards lower serum IgE levels in the prophylactic-treated group at 4 months (p < 0.07). In the control group, formula feeding prior to 4 months was associated with higher 4 month serum IgE levels (p < 0.05). Stepwise linear regression revealed that serum IgE variability from birth to 4 years was influenced by male gender, non-caucasian ethnicity, maternal and paternal serum IgE levels, 4 month IgG BLG levels, positive food and inhalant skin tests, and the development of atopic dermatitis, food allergy, asthma, and allergic rhinitis. These findings demonstrate the strength of genetic factors and their modulation by dietary and envi-ronmental influences in the development of atopy and reveal that the reduction in food allergy in infancy by maternal/infant food allergen avoidance fails to affect respiratory allergy development from birth to 4 years.     

Prevalence of asthma at school age: a clinical population-based study in eastern Finland

A questionnaire aimed at screening and identifying patients with asthmatic symptoms was sent to the parents of 2011 children aged 7 to 12 years; 1633 (81%) returned the questionnaire. A clinical examination was given to 165 symptomatic and 82 non-symptomatic children. The children were classified into three groups: I, clinical asthma ( n =43); 2, other symptoms from lower airways (OSLA) ( n =34); 3, healthy children ( n = 170). The prevalences of asthma and OSLA in the whole source population ( n = 1633) were then estimated based on these figures. The lifetime prevalence of asthma was 4.0%. All children with asthma were either symptomatic or on continuous maintenance therapy during the preceding 12 months. The lifetime prevalence of OSLA was 5.0%, with 3.0% being symptomatic during the preceding 12 months. Asthma was more common in boys (5.0%) than in girls (2.8%). The respective figures for OSLA were 6.2 and 3.7%. The occurrence of asthma as well as respiratory symptoms suggestive of asthma was more common than previously observed in this area.     

Does heredity modify the association between farming and allergy in children?

AIM: It has been suggested that living on a farm decreases the risk of childhood allergy, especially if farming involves livestock. The aim of this study was to examine the association between farming and allergy in children, and the influence of atopic heredity in this association. METHODS: The cross-sectional data of the 7981 children aged 13-14 y who participated in the Finnish ISAAC study between the years 1994 and 1995 were used to evaluate the association between farming and allergy. RESULTS: Living on a farm was associated with a decreased risk of current symptoms of allergic rhinoconjunctivitis among all children (aOR 0.79; 95% CI 0.63, 0.99), and with a decreased risk of hay fever, especially among those children with a parental history of hayfever (aOR 0.60; 95% CI 0.40-0.89, p = 0.072 for interaction). The children of farmers with a history of hay fever also had a decreased risk of current wheeze (aOR 0.38; 95% CI 0.12-1.24, p = 0.040 for interaction). No significant association was found between farming and either asthma or eczema. Children living on a farm with livestock had the lowest risk of allergic rhinoconjunctivitis (aOR 0.69), followed by those living on a farm without livestock (aOR 0.89) compared with the non-farming children (p-value for trend 0.024). CONCLUSION: Our results support the recent findings on a decreased risk of allergy among the children living on farms. A possible differential effect of parental history of hay fever on the relation of farming environment and the risk of allergic symptoms warrant further investigation.     

Effects of early intake of fruit or vegetables in relation to later asthma and allergic sensitization in school-age children

AIM: To assess the associations between nutrition supplements in infancy and later asthma and allergy in school-age children, and to explore the impact of environmental factors in early life. METHODS: Five hundred and two children underwent clinical examination, skin prick test and a second parentally completed questionnaire within 2 y of a cross-sectional questionnairebased study, including 4585 primary school children (6-16 y old) in 1994 from urban Oslo (37%), the mountainous area of Hallingdal (42%), and the industrial, coastal area of Odda (21%). The children were selected from the 1994 survey on the basis of reported diagnosed asthma (n=166), wheeze in the last 12 mo (n=155) and no asthma/no wheeze (n=181). Questions were related to nutrition and environmental exposure in early life. Possible associations between allergic sensitization or asthma at school age and exposures were estimated by logistic regression analysis, adjusting for potential confounders. RESULTS: Daily intake of fresh fruit or vegetables, but not extra vitamins or cod liver oil supplements, in infancy decreased the risk of asthma (adjusted odds ratio (aOR) 0.57 (95% confidence interval (CI): 0.37-0.88). Early supplements of cod liver oil and extra vitamins were associated with increased allergic sensitization (aOR 1.78 (95% CI: 1.03-3.07) and 1.71 (95% CI: 1.01-2.88), respectively). A significantly higher prevalence of allergic sensitization was found in children living in Hallingdal compared to Odda, while the latter children, on the other hand, had the highest prevalence of house dust mite allergy (p = 0.001 vs Hallingdal and p = 0.04 vs Oslo). CONCLUSION: The present study suggests that the early introduction of daily fresh fruit or vegetables may decrease the risk of asthma after 1 y of life, whereas allergic sensitization at school age seemed to increase with extra vitamin and cod liver oil supplements during infancy. Living area influenced allergic sensitization, with differences between coastal and inland areas.     

Lack of an inverse association between tuberculosis infection and atopy: By T-cell-based immune assay (RD1–ELISpot)

The association between mycobacterial exposure, vaccination with bacillus Calmette-Guerin (BCG) in early life and atopy remains controversial. Distinguishing between environmental mycobacterial exposure, TB infection and BCG-vaccination is not possible with the tuberculin skin test (TST) but new accurate blood-tests for TB infection present an opportunity to differentiate TB infection from environmental mycobacterial exposure and BCG-vaccination. We used a new blood test in parallel with TST to investigate whether Mycobacterium tuberculosis infection and/or BCG vaccination are associated with development of atopy in children with prior household TB contacts. All children who had contact with adult active pulmonary TB during the last 6 months underwent TST, chest radiography, and RD1–ELISpot assay. The presence of a BCG scar was documented, and assessment of atopy was carried out by International Study of Asthma and Allergies in Childhood questionnaire, allergy skin prick testing (SPT) and evaluation of serum total IgE. Among 361 children enrolled 39 (11%) had a positive SPT, 236 (63%) positive TST, and 189 (52%) positive RD1–ELISpot. The frequency of SPT positivity, ever wheezing, allergic rhinitis, doctor-diagnosed asthma, high serum IgE level, and median total serum IgE levels did not differ significantly different by TST or RD1–ELISpot status. On the other hand, presence of BGC scar was associated with lower median total serum IgE level (p = 0.01) and lower frequency of high IgE (p = 0.003). M. tuberculosis infection whether measured by TST or RD1–ELISpot, was not associated with atopy in children with household TB contact. Presence of a BCG vaccination scar was inversely associated with atopy, as measured by serum IgE.     

Role of elevated immunoglobulin E levels in suppurative otitis media

BACKGROUND AND OBJECTIVES: An association between suppurative otitis media (SOM) and allergy has been reported in about 80% of patients with allergy. However, there is controversy regarding their relationship and the concept of middle-ear allergic response. We test the hypothesis that increased secretion of IgE in the middle ear is higher in chronic than in acute SOM. METHODS: Allergy skin testing and enzyme-linked immunoassay of specimens of middle-ear secretions and sera were analysed. RESULTS: Paired sera and middle-ear secretions (MES) from 37 subjects with SOM, 20 chronic (CSOM) and 17 acute (ASOM), and sera of 15 controls selected from children without otitis media were analysed. There were 30 males and 27 females aged between 6 months and 9 years, mean (SD) 6 years (3.26). A history of allergy and skin test positive to one or more of dust, house dust mite, mould, cockroach and poultry feathers were found in 80% of CSOM, 47% ASOM and 33% controls. The mean IgE levels in sera were: controls 52.1 mg/dL, ASOM 63.9 mg/dL and CSOM 79.2 mg/dL; the MES levels were: AOM 60.4 mg/dL and CSOM 102.0 mg/dL. The MES to serum IgE ratios were 0.75 for ASOM and 1.4 for CSOM. The serum IgE ratio of controls to ASOM was 1.22 and to CSOM was 1.5. Multivariate analysis of the mean showed significant correlation between IgE level of MES in ASOM and CSOM (p=0.04) but no correlation between IgE levels in control and ASOM sera (p=0.10), control and CSOM sera (p=0.7) or AOM and CSOM sera (p=0.3). CONCLUSION: Allergy appears to play a contributory role in CSOM and elevated IgE in the MES suggests a likely mucosal response.     

Atopy patch testing in children with asthma and rhinitis symptoms allergic to house dust mite

The atopy patch test (APT) is generally used to assess immunoglobulin E (IgE) mediated sensitization to allergens in patients with atopic dermatitis, but its diagnostic role in children with respiratory allergy is still controversial. The aim of the study was to evaluate APT with house dust mite (HDM) in children with asthma and rhinitis symptoms allergic to HDM and its relevance to skin prick test (SPT) diameters and specific IgE levels. The study population consisted of 33 children, aged 8-16 yr (median: 12 yr) with asthma and 30 children with allergic rhinitis in the same age range (median: 11 yr). All patients had positive SPT results and high serum specific IgE levels for Dermatophagoides pteronyssinus APT was performed on back skin of all patients with 200 index of reactivity (IR)/ml of D. pteronyssinus allergen extracts in petrolatum (Stallerpatch) and evaluated at 72 h. Of 63 patients, 16 (25%) showed a positive patch test result. APT with HDM showed 30% (10/33) positivity among the patients with asthma and 20% (6/30) positivity among the patients with allergic rhinitis. APT presented no significant correlation with age, SPT diameter, serum total and specific IgE levels for D. pteronyssinus, nasal provocation test or pulmonary function test results. Patch testing with HDM may partly identify mite sensitive children with respiratory allergy. Positive APT results may imply that delayed hypersensitivity reactions play a role in children with asthma and rhinitis allergic to HDM.     

温州地区402例哮喘患儿特应质现象分析

目的 对温州地区15岁以下哮喘患儿特应质现象进行分析,探讨其临床及理论价值.方法 回顾性分析402例哮喘患儿皮肤过敏原诊断试验、血清特异性IgE、总IgE、个人过敏史、家族史、过敏原检出率、类型及与年龄关系.结果 哮喘发病有家族聚集倾向,家族过敏史总阳性率为52.74%.个人过敏史总阳性率为61.69%.过敏原皮肤诊断试验和过敏原血清特异IgE阳性率达83.58%,吸人性过敏原阳性人数占检测患儿的74.13%,其中以粉尘螨(61.44%)、屋尘螨(58.96%)为主;食人性过敏原阳性占24.38%,以小虾(16.67%)、牛奶(8.46%)为主.血清总IgE阳性率87.9%,总IgE阳性组和阴性组的哮喘患儿血清嗜酸性细胞阳离子蛋白(ECP)、户尘螨sIgE(D1)、粉尘螨sIgE(D2),皮肤过敏原诊断试验(pt)、家族过敏史、个人过敏史差异有统计学意义(P均≤0.05).哮喘患儿3岁前、后过敏原分布不同,3岁以后吸人性过敏原阳性为主.发病诱因中以上呼吸道感染为最多,哮喘症状发作的时间主要集中在临睡、夜晚、清晨.结论 儿童哮喘存在明显特应质现象,对其的正确认识和诊断对哮喘免疫机制的深入研究、综合治疗如在糖皮质激素吸入治疗的基础上,增加患儿教育、过敏原避免、特异性的免疫治疗等具有实用和理论指导意义.     

Sublingual desensitization in children with congenital malformations and latex allergy

The frequency of latex allergy in children requiring multiple surgery ranges from 16.7% to 65%. The aim of this study was to investigate the safety and efficacy of latex desensitization in a group of 10 patients with a history of multiple surgical procedures and clinically manifested allergy to latex. We selected 10 children (female-male ratio = 5:5), aged 4-16 yr (mean +/- s.d.: 9 +/- 4), with a history of multiple surgical procedures, adverse reactions to latex and positive skin test to latex and/or specific immunoglobulin E (IgE). Latex allergy diagnosis was confirmed by specific provocation tests (cutaneous, sublingual, mucous, conjunctival tests). Rush (4-day) sublingual desensitization was performed with increasing doses of latex extract (ALK Abellò) under patients' tongue until the highest dose of 500 microg of latex. A maintenance therapy (10 drops of undiluted solution three times a week) was recommended. During the 2-yr follow-up mean values of specific IgG4 and IgE, eosinophilic cationic protein and total IgE did not show significant variations. Patients did not manifest any adverse effect during the rush phase and only two patients manifested mild local symptoms during the maintenance therapy. All the challenges showed a reduction in terms of percentage of positivity and mean scores. All the patients showed a reduction of the mean individual score (p < 0.001). Furthermore patients who needed dental examination or surgery underwent such procedures without the occurrence of symptoms. Our preliminary results show sublingual desensitization to latex can be an important therapeutic tool in the management of young allergic patients requiring multiple operations.     

Different serum interleukin‐12 and sCD30 levels in food‐ and pollen‐sensitized children

It has been proposed that a down-regulation of interleukin (IL)-12 and interferon (IFN)-γ might be related to susceptibility to allergy in early life. The aim of this study was to assess serum IL-12 levels in food-sensitized and pollen-sensitized children and to compare these with another activation marker, sCD30. Twenty children with pollen allergy and 22 food-sensitized children were included. The diagnosis of immunoglobulin (Ig)-E-mediated allergy, suggested by clinical symptoms, was based on skin-prick tests, serum IgE antibodies and total IgE levels. Samples from 24 non-allergic children were used as controls. IL-12 and sCD30 levels were measured by ELISA. It was found that pollen-sensitized patients had normal IL-12 and higher sCD30 levels than controls (114 vs. 63 U/ml, p = 0.028), but, surprisingly, food-sensitized infants showed normal sCD30 and increased serum IL-12 levels (323 vs. 118 pg/ml, p = 0.0001). No differences were found in patients suffering from asthma or allergic dermatitis. Levels of sCD30 and IL-12 determined in May showed a strong correlation with those obtained in November. Interleukin-12 and IgE levels had an inverse correlation (r = –0.494, p = 0.0001) whereas no correlation was found between sCD30 and IgE. Age had a strong negative influence on IL-12 levels in allergic (Z = 4.834, p < 0.0005) and in normal children (Z = 3.00, p < 0.002); by contrast, sCD30 levels were not significantly age-dependent. When IL-12 levels from the food-allergy group were compared with those from normal controls younger than 4 years of age, the difference remained significant (p = 0.001), ruling out an age-bias. The conclusions made in this study were that serum IL-12 and sCD30 showed different behaviors in children with food or pollen allergy. We found IL-12 and sCD30 levels in pollen-allergic patients that agree with the classical T-helper (Th) 1/Th2 paradigm of allergy. In contrast, serum IL-12 levels were increased in food-sensitized children, suggesting a different immunologic pathogenesis.     

Analysis of basophil activation by flow cytometry in pediatric house dust mite allergy

Detection of allergen‐induced basophil activation by flow cytometry has been shown to be a useful tool for allergy diagnosis. The aim of this study was to assess the potential of this technique for the diagnosis of pediatric house dust mite allergy. Quantification of total and specific IgE and basophil activation test were performed to evaluate mite allergic (n = 24), atopic (n = 23), and non‐allergic children (n = 9). Allergen‐induced basophil activation was detected as a CD63‐upregulation. Receiver operating characteristics (ROC) curve analysis was performed to calculate the optimal cut‐off value of activated basophils discriminating mite allergic and non‐allergic children. ROC curve analysis yielded a threshold value of 18% activated basophils when mite‐sensitized and atopic children were studied [area under the curve (AUC) = 0.99, 95% confidence interval (CI) = 0.97–1.01, p < 0.001] with a sensitivity and specificity of 96% for 16 μg/ml mite extract. Analysis of the data obtained with 1.6 μg/ml mite extract defined a cut‐off value of 8% activated basophils (AUC = 0.96, 95% CI = 0.91–1.01; p < 0.001) with a sensitivity of 82% and specificity of 100%. Comparison between mite allergic and non‐allergic children produced a cut‐off of 8% activated basophils (AUC = 1.0) with 16 μg/ml allergen extract and a sensitivity and specificity of 100%. The same threshold and specificity values were obtained with 1.6 μg/ml extract (AUC = 97%, 95% CI = 0.92–1.02; p < 0.001) but sensitivity decreased to 83%. Two atopic children showed negative skin prick and basophil activation tests and high specific IgE (>43 kU/l) values for Dermatophagoides pteronyssinus allergen. They also showed positive prick (wheal diameter >1.0 cm) and basophil activation (>87%) tests and high specific IgE (>100 kU/l) with shrimp allergen. Shrimp sensitization was demonstrated by high levels of Pen a 1‐specific IgE (>100 kU/l). Cross‐reactivity between mite and shrimp was confirmed by fluorescence enzyme immunoassay (FEIA‐CAP) inhibition study in these two cases. This study demonstrated that the analysis of allergen‐induced CD63 upregulation by flow cytometry is a reliable tool for diagnosis of mite allergy in pediatric patients, with sensitivity similar to routine diagnostic tests and a higher specificity. Furthermore, this method can provide additional information in case of disagreement between in vivo and in vitro test results.