Allergy testing in children: why, who, when and how?

Risk factors of sleep-disordered breathing and poor asthma control in children with asthma

BACKGROUND

Sleep-disordered breathing (SDB) may lead to poor asthma control in children.

OBJECTIVE

To identify risk factors of SDB in children with asthma and assess its impact on asthma control.

METHODS

In this cross-sectional study, we collected data of outpatients with asthma at the Children's Hospital of Chongqing Medical University from June 2020 to August 2021. The Pediatric Sleep Questionnaire-Sleep-Related Breathing Disorder and the age-appropriate asthma control tests Childhood Asthma Control Test and Test for Respiratory and Asthma Control in Kids were completed.

RESULTS

We enrolled 397 children with a male-to-female ratio of 1.7:1 and a mean age of 5.70 ± 2.53 years. The prevalence of SDB was 21.6%. Allergic rhinitis (odds ratio OR = 3.316), chronic tonsillitis (OR = 2.246), gastroesophageal reflux (OR = 7.518), adenoid hypertrophy (OR = 3.479), recurrent respiratory infections (OR = 2.195), and a family history of snoring (OR = 2.048) were risk factors for the development of combined SDB in children with asthma (p < 0.05). Asthma was poorly controlled in 19.6% of the children. SDB (OR = 2.391) and irregular medication use (OR = 2.571) were risk factors for poor asthma control (p < 0.05).

CONCLUSIONS

Allergic rhinitis, chronic tonsillitis, gastroesophageal reflux, adenoid hypertrophy, recurrent respiratory infections, and a family history of snoring were independent risk factors for the development of SDB in children with asthma. SDB and irregular medication use were independent risk factors for poor asthma control.

Quality of life in children with food allergies, psychiatric symptoms, and caregiving burden of their mothers

OBJECTIVE

The present study aimed to evaluate the quality of life in children with food allergies, the accompanying depression and anxiety disorders, and caregiving burden of their mothers.

MATERIAL AND METHODS

A total of 168 children with food allergy visiting our clinic and their mothers were included in the study group. The control group included 152 children who visited the healthy child follow-up clinic of our hospital and their mothers. Studying mothers' opinions, the Food Allergy Quality of Life Questionnaire Parent Form (FAQLQ-PF) was used for evaluating children, and the Beck's Depression Inventory, Beck's Anxiety Inventory, Temperament Evaluation of Memphis, Pisa, Paris, San Diego Auto-questionnaire, and Zarit Caregiver Burden Scales were used for evaluating mothers.

RESULTS

No differences were noticed between the study and control group regarding mean age and gender distribution (P > 0.05). In the study, the FAQLQ-PF total and subscale scores of children with food allergies were determined according to the opinions of their mothers, and scores tended to increase with age (P < 0.0001). In addition, it was determined that mothers of children with food allergies had higher levels of anxiety, depression, and caregiving burden than mothers of the control group (P < 0.0001).

CONCLUSION

In order to develop a multidisciplinary approach for children with food allergies, we conceived as appropriate to inform their families about the difficulties of caregiving and psychosocial disorders that could develop over time. They also must be informed to take preventive measures as well as the medical aspects of their children's disease.

Drug allergy evaluation in children with suspected mild antibiotic allergy

Background

Adverse antibiotic reactions caused by an immunological mechanism are known as allergic reactions. The percentage of reported antibiotic allergies is likely to differ from the one validated after a drug provocation test (DPT) with the culprit antibiotic. This study aimed to compare the percentage of children who were thought to be allergic to a certain antibiotic with those who have a true allergy, as confirmed by DPTs. We also validated Skin Prick Tests (SPTs) and Intradermal Tests (IDTs) by assessing their sensitivity and specificity, in diagnosing antibiotic allergies using DPT as the gold standard. Furthermore, we investigated epidemiological risk factors such as personal and family history of atopic disease and eosinophilia.

Methods

Children with a history of possible allergic reaction to an antibiotic underwent a diagnostic procedure that included: (1) Eosinophil blood count, (2) SPTs, (3) IDTs and (4) DPTs. The parameters were compared with Pearson's Chi-Square and Fisher's Exact Test. Several risk factors that were found significant in univariate analysis, such as personal and family history of atopic disease, and positive SPTs and IDTs were examined with multiple logistic regression analysis to see if they were related to a higher risk for a positive DPT.

Results

Semi-synthetic penicillin was the most common group of antibiotics thought to cause allergic reactions in this study. Overall, 123 children with a personal history of an adverse reaction to a certain antibiotic, were evaluated. In 87.8% of the cases, the symptoms had occurred several hours after administration of the culprit antibiotic. Both SPTs and IDTs had low sensitivity but high specificity. Moreover, they had a high positive predictive value (PPV). In contrast, eosinophilia was not recognized as a risk factor. Seventeen patients (13.8%) had a true antibiotic allergy, as confirmed by a positive DPT. A positive IDT was a strong predictor of a positive DPT, along with a positive personal and family history of atopy.

Conclusion

SPTs and IDTs are very reliable in confirming antibiotic allergy when found positive. A negative result of a SPT highly predicts a negative DPT. A positive IDT and a positive personal and family history of atopy were recognized as significant risk factors for antibiotic allergy.

Nasopharyngeal microbial profiles associated with the risk of airway allergies in early childhood

BACKGROUND

Airway microbiota may play an important role in regulating the immune response related to allergic respiratory diseases. A molecular-based approach was used to analyze the association between nasopharyngeal microbiota, serum immunoglobin (Ig)E levels, and childhood respiratory allergies.

METHODS

Nasopharyngeal swabs were collected from children aged 36 months with three phenotypes, including allergic respiratory diseases plus atopy, atopy alone, and healthy controls for microbiome analysis using Illumina-based 16S rRNA gene sequencing.

RESULTS

In total, 87 children were enrolled, including 36 with allergic respiratory diseases plus atopy, 21 with atopy alone, and 30 healthy controls. Proteobacteria (45.7%), Firmicutes (29.3%), and Actinobacteria (15.3%) were the most prevalent phyla in the study population. Compared with healthy controls, a lower Chao1 index was found in children with allergies (P < 0.035), indicating that bacterial richness was inversely associated with airway allergies. Additionally, in comparison with healthy controls, the genera Acinetobacter, Moraxella, Asaia, and Rhodococcus were more abundant and positively correlated with total serum IgE levels in children with allergies (P < 0.01), whereas the genera Enterococcus and Rickettsia were inversely correlated with total IgE levels, and also appeared to be negatively associated with airway allergies (P < 0.01).

CONCLUSIONS

The composition of the nasopharyngeal microbiota alteration may have an influence on childhood respiratory allergies. The inverse association between bacterial richness and allergies postulated that children living in a microbially hygienic environment may increase their risk of developing respiratory allergies.

Contact Dermatitis: Classifications and Management

Contact dermatitis (CD) is a common inflammatory skin disease caused by exposure to contact allergens and irritants. It is also the most common reason of occupational dermatitis and contributes greatly to hand dermatitis and facial dermatitis. Besides the two major forms of contact dermatitis: allergic contact dermatitis and irritant contact dermatitis, other subtypes of CD have been recognized including immediate skin reactions, photoinduced contact dermatitis, systemic contact dermatitis, and non-eczematous contact dermatitis. CD is a great imitator which can mimic many kinds of skin diseases, such as atopic dermatitis, lichen planus, and angioedema. For the diagnosis of CD, a complete medical history, including occupational history, is very important. It can give a clue of CD and provide a list of suspected substances. Besides the well-known diagnostic test, patch testing, there are many other diagnostic tests can be used to help diagnosis of CD and identify the causative allergens, including photopatch test, skin tests for detecting of immediate contact reactions, serum allergen-specific IgE test, and qualitative and quantitative testing of allergen in the suspected materials patients exposed to and challenge test. Before the treatment, the suspected irritants or allergens should be avoided completely. This includes both the removal of the patient from the environment that contains those substances and the promotion of the metabolism and expulsion of the allergens that have been absorbed by the body. In addition, it is also important to restore the skin barrier and reduce skin inflammation through multiple treatments, such as emollients, topical corticosteroids, and antihistamines, as well as systemic corticosteroids and immunosuppressants. Early and appropriate treatments are important to prevent further deterioration and persistence of the skin condition.

Single and multiple time-point allergic sensitization during childhood and risk of asthma by age 13

BACKGROUND

The relationship between allergic sensitization during childhood and risk of developing asthma remains unclear.

OBJECTIVE

To analyze single time-point and temporal patterns of sensitization in childhood in relation to asthma at age 13.

METHODS

Specific IgE (sIgE) level and skin prick test (SPT) toward 22 food allergens and aeroallergens were assessed at 6, 18 months, 4, 6, and 13 years in children from the high-risk Copenhagen Prospective Studies on Asthma in Childhood₂₀₀₀ (COPSAC₂₀₀₀ ) mother-child cohort. We analyzed the association between single time-point monosensitization, polysensitization, and quantitative assessment of sensitization, that is, sum of all sIgE levels and SPT wheal sizes, against asthma at age 13. In addition, we analyzed the association between three temporal patterns of sensitization: (a) early-transient, (b) late-onset, and (c) persistent sensitization and asthma.

RESULTS

Polysensitization status measured by SPT or sIgE was at all single time-points associated with increased risk of asthma at age 13: OR range, SPT = 3.0-15.7, and sIgE = 2.6-15.7, respectively, whereas monosensitization status was inconsistently associated with asthma. Quantitative assessment of both sIgE and SPT results was associated with asthma at all single time-points: OR range, SPT = 1.3-3.6, and sIgE = 1.1-1.7. Persistent sensitization, but not early-transient or late-onset sensitization was associated with asthma by age 13: OR [95% CI], SPT = 8.9 [2.8-28.23], and sIgE = 2.9 [1.1-7.6], respectively.

CONCLUSION

Sensitization to multiple allergens at single time-points, increasing sIgE levels and SPT wheal sizes, and persistent sensitization during childhood were associated with increased risk of asthma at age 13, suggesting the use of quantitative and repetitive sensitization measurements when assessing risk of developing asthma.

Storage mite concentrations are underestimated compared to house dust mite concentrations

Dwellings are increasingly well insulated to save energy and this leads to higher humidity and temperature, which improves conditions for mites. Dermatophagoides antigens are the main allergens involved and tested in atopic asthma. We developed three new species-specific quantitative PCR (qPCR) methods for house dust mites (Dermatophagoides pteronyssinus and D. farinae) and storages mites (Acarus siro, Glycyphagus domesticus, Lepidoglyphus destructor). We sampled dust with electrostatic dust collectors, in the bedrooms, under beds and in the kitchens of patients with allergies (n = 24) and healthy controls (n = 18). Mite quantification was carried out with the three new qPCRs and the qPCR previously described for the Dermatophagoides genus. The qPCRs were highly specific and efficient for house dust mite species and the storage mites. Storage mite concentrations were higher than house dust mite concentrations and were higher in dwellings of patients with allergies. Consequently, allergists should test more often patients against the storage mite antigens by prick tests or IgE serology. Dampness is a major factor in storage mite development and the presence of effective mechanical ventilation can reduce storage mite concentrations four-fold. In addition, to limit exposure to dust mites, treatments should be used throughout dwellings and not only in patients' bedrooms.

Gut microbial dysbiosis is associated with allergen-specific IgE responses in young children with airway allergies

Background

There is increasing evidence linking alterations of the gut microbial composition during early infancy to the development of atopic diseases and asthma. However, few studies have addressed the association of dysbiotic gut microbiota with allergic reactions through evaluation of feces in young children with allergic airway diseases.

Methods

We sought to evaluate relationships among gut microbiota, total fecal immunoglobulin E (IgE) levels, serum allergic sensitization, and their relevance to childhood allergic rhinitis and asthma. Microbial composition and diversity were analyzed with Illumina-based 16S rRNA gene sequencing of 89 stool samples collected from children with asthma (n = 35) and allergic rhinitis (n = 28), and from healthy controls (n = 26). Data analysis was performed using Quantitative Insights into Microbial Ecology (QIIME) software.

Results

A significantly lower abundance of organisms of the phylum Firmicutes were found in children with asthma and allergic rhinitis than in the healthy controls. Relatively lower Chao1 and Shannon indices were also found in children with allergic airway diseases but without any significant difference. Total fecal IgE levels in early childhood were strongly correlated with serum D. pteronyssinus- and D. farinae-specific IgE but not with food-specific IgE levels. In comparison with healthy controls, the genus Dorea was less abundant and negatively correlated with total fecal IgE levels in children with rhinitis, whereas the genus Clostridium was abundant and positively correlated with fecal IgE levels in children with asthma.

Conclusions

An interaction between particular subsets of gut microbial dysbiosis and IgE-mediated responses to allergens may contribute to the susceptibility to allergic rhinitis and asthma in early childhood.

Recognition and management of food allergy in children

Incidence of food allergy has been increasing and is more commonly seen in children. Allergic reactions can vary, with symptoms ranging from mild to severe. This article aims to explore the immunological mechanisms involved in food allergy, as well as distinguishing between immunoglobulin E (IgE) mediated and non-IgE-mediated reactions. Careful diagnosis of the allergic child is essential and the article describes validated tests carried out in this process. Adopting a multidisciplinary approach to the management of children with allergies is vital because it ensures patients and carers are supported, empowered and therefore able to enjoy an improved quality of life.

Modifiable Risk Factors for Common Ragweed (Ambrosia artemisiifolia) Allergy and Disease in Children: A Case-Control Study

Ragweed allergy is a major public health concern. Within Europe, ragweed is an introduced species and research has indicated that the amounts of ragweed pollen are likely to increase over Europe due to climate change, with corresponding increases in ragweed allergy. To address this threat, improving our understanding of predisposing factors for allergic sensitisation to ragweed and disease is necessary, specifically focusing upon factors that are potentially modifiable (i.e., environmental). In this study, a total of 4013 children aged 2–13 years were recruited across Croatia to undergo skin prick tests to determine sensitisation to ragweed and other aeroallergens. A parental questionnaire collected home environment, lifestyle, family and personal medical history, and socioeconomic information. Environmental variables were obtained using Geographical Information Systems and data from nearby pollen, weather, and air pollution stations. Logistic regression was performed (clustered on school) focusing on risk factors for allergic sensitisation and disease. Ragweed sensitisation was strongly associated with ragweed pollen at levels over 5000 grains m^–3 year⁻¹ and, above these levels, the risk of sensitisation was 12–16 times greater than in low pollen areas with about 400 grains m^–3 year⁻¹. Genetic factors were strongly associated with sensitisation but nearly all potentially modifiable factors were insignificant. This included measures of local land use and proximity to potential sources of ragweed pollen. Rural residence was protective (odds ratio (OR) 0.73, 95% confidence interval (CI) 0.55–0.98), but the factors underlying this association were unclear. Being sensitised to ragweed doubled (OR 2.17, 95% CI 1.59–2.96) the risk of rhinoconjunctivitis. No other potentially modifiable risk factors were associated with rhinoconjunctivitis. Ragweed sensitisation was strongly associated with ragweed pollen, and sensitisation was significantly associated with rhinoconjunctivitis. Apart from ragweed pollen levels, few other potentially modifiable factors were significantly associated with ragweed sensitisation. Hence, strategies to lower the risk of sensitisation should focus upon ragweed control.

Asthmatic/wheezing phenotypes in preschool children: Influential factors, health care and urban-rural differences

BACKGROUND

Different wheezing and asthmatic phenotypes turned out to indicate differences in etiology, risk factors and health care. We examined influential factors and urban-rural differences for different phenotypes.

METHODS

Parents of 4732 children filled out a questionnaire concerning children's health and environmental factors administered within the Health Monitoring Units (GME) in a cross-sectional study in Bavaria, Germany (2014/2015). To classify respiratory symptoms, five phenotype groups were built: episodic, unremitting and frequent wheeze, ISAAC (International Study of Asthma and Allergies in Children) - asthma and physician-diagnosed asthma (neither of the groups are mutually exclusive). For each phenotype, health care variables were presented and stratified for residence. Urban-rural differences were tested by Pearson's chi-squared tests. Multivariable logistic regression was performed to analyze associations between influential factors and belonging to a phenotype group, and to compare groups with regard to health care variables as outcome.

RESULTS

Risk factors for wheezing phenotypes were male gender (OR = 2.02, 95%-CI = [1.65-2.48]), having older siblings (OR = 1.24, 95%-CI = [1.02-1.51]), and preterm delivery (OR = 1.61, 95%-CI = [1.13-2.29]) (ORs for unremitting wheeze). 57% of children with ISAAC asthma and 74% with physician-diagnosed asthma had performed allergy tests. Medication intake among all groups was more frequent in rural areas, and physician's asthma diagnoses were more frequent in urban areas.

CONCLUSIONS

In accordance with previous research this study confirms that male gender, older siblings and preterm delivery are associated with several wheezing phenotypes. Overall, low numbers of allergy tests among children with physician's diagnoses highlight a discrepancy between common practice and current knowledge and guidelines. Residential differences in health care might encourage further research and interventions strategies.

Serum Diamine Oxidase in Pseudoallergy in the Pediatric Population

Histamine intolerance (pseudoallergy) is a poorly investigated type of food hypersensitivity. The main enzyme responsible for histamine degradation in the extracellular matrix is diamine oxidase (DAO). Disturbances in the concentration or activity of DAO may lead to the development of clinical signs of allergy. The aim of the present work was to assess the DAO concentration, peripheral blood morphology, lymphocytes phenotyping (CD3+, CD4+, CD8+, CD19+, NK cells, NKT cells, and activated T-cells), and natural regulatory Treg (nTregs) cell population (CD4+, CD25+, CD127low, and FoxP3) in 34 pediatric patients with histamine-dependent syndromes. Patients were divided into two groups: classical allergy and pseudoallergy on the basis of IgE concentration. The investigation was based on the analysis of peripheral blood samples. A significantly lower serum DAO, both total and specific IgE, concentration was found in the pseudoallergy group compared with the allergy group. There were no significant differences in blood morphology or lymphocyte populations. A similar level of nTreg lymphocytes was also found in both groups, although it was lower than that present in healthy individuals. The findings suggest that the serum DAO is responsible for the symptoms of histamine intolerance. Moreover, a general decrease in nTreg cells in comparison with healthy individuals may lead to symptom aggravation.

Risk factors for recurrent wheezing in infants: a case-control study

OBJECTIVE

To evaluate the association between recurrent wheezing and atopy, the Asthma Predictive Index, exposure to risk factors, and total serum IgE levels as potential factors to predict recurrent wheezing.

METHODS

A case-control study with infants aged 6-24 months treated at a specialized outpatient clinic from November 2011 to March 2013. Evaluations included sensitivity to inhalant and food antigens, positive Asthma Predictive Index, and other risk factors for recurrent wheezing (smoking during pregnancy, presence of indoor smoke, viral infections, and total serum IgE levels).

RESULTS

We evaluated 113 children: 65 infants with recurrent wheezing (63.0% male) with a mean age of 14.8 (SD = 5.2) months and 48 healthy infants (44.0% male) with a mean age of 15.2 (SD = 5.1) months. In the multiple analysis model, antigen sensitivity (OR = 12.45; 95%CI 1.28–19.11), positive Asthma Predictive Index (OR = 5.57; 95%CI 2.23–7.96), and exposure to environmental smoke (OR = 2.63; 95%CI 1.09–6.30) remained as risk factors for wheezing. Eosinophilia ≥ 4.0% e total IgE ≥ 100 UI/mL were more prevalent in the wheezing group, but failed to remain in the model. Smoking during pregnancy was identified in a small number of mothers, and secondhand smoke at home was higher in the control group.

CONCLUSIONS

Presence of atopy, positive Asthma Predictive Index and exposure to environmental smoke are associated to recurrent wheezing. Identifying these factors enables the adoption of preventive measures, especially for children susceptible to persistent wheezing and future asthma onset.

Evaluation of a novel automated allergy microarray platform compared with three other allergy test methods

Microarray platforms, enabling simultaneous measurement of many allergens with a small serum sample, are potentially powerful tools in allergy diagnostics. We report here the first study comparing a fully automated microarray system, the Microtest allergy system, with a manual microarray platform, Immuno-Solid phase Allergen Chip (ISAC), and two well-established singleplex allergy tests, skin prick test (SPT) and ImmunoCAP, all tested on the same patients. One hundred and three adult allergic patients attending the allergy clinic were included into the study. All patients were tested with four allergy test methods (SPT, ImmunoCAP, Microtest and ISAC 112) and a total of 3485 pairwise test results were analysed and compared. The four methods showed comparable results with a positive/negative agreement of 81-88% for any pair of test methods compared, which is in line with data in the literature. The most prevalent allergens (cat, dog, mite, timothy, birch and peanut) and their individual allergen components revealed an agreement between methods with correlation coefficients between 0·73 and 0·95. All four methods revealed deviating individual patient results for a minority of patients. These results indicate that microarray platforms are efficient and useful tools to characterize the specific immunoglobulin (Ig)E profile of allergic patients using a small volume of serum sample. The results produced by the Microtest system were in agreement with diagnostic tests in current use. Further data collection and evaluation are needed for other populations, geographical regions and allergens.

[Respiratory allergies in children and adolescents: the role of component-resolved diagnosis and specific immunotherapy]

Respiratory allergies of children and adolescents are an important issue in allergology. In parallel to increasing prevalence rates also research has rapidly been developing for the last 10 years. Today we can better understand complex systems to improve our diagnostic and therapeutic accuracy. In addition to medical history, skin-prick-testing and analysis of specific IgE to allergen extracts, component resolved diagnosis has gained importance in the last years. While being increasingly helpful in the diagnosis of insect-venom and food-allergies, component-based diagnosis can also improve the management of patients with respiratory allergies. Concerning different therapeutic approaches like allergen-avoidance or symptomatic therapy, specific immunotherapy (SIT) is one of the most interesting therapy-options, as it is still the only causal therapy available. After reasonable patient-selection and the selection of the right allergen and product, SIT has a very good risk/benefit-ration and can induce long-term immuno-tolerance to specific allergens.

Long-Term Burden and Respiratory Effects of Respiratory Syncytial Virus Hospitalization in Preterm Infants-The SPRING Study

The health status of premature infants born 32¹-35⁰ weeks’ gestational age (wGA) hospitalized for RSV infection in the first year of life (cases; n = 125) was compared to that of premature infants not hospitalized for RSV (controls; n = 362) through 6 years. The primary endpoints were the percentage of children with wheezing between 2-6 years and lung function at 6 years of age. Secondary endpoints included quality of life, healthcare resource use, and allergic sensitization. A significantly higher proportion of cases than controls experienced recurrent wheezing through 6 years of age (46.7% vs. 27.4%; p = 0.001). The vast majority of lung function tests appeared normal at 6 years of age in both cohorts. In children with pulmonary function in the lower limit of normality (FEV₁ Z-score [-2; -1]), wheezing was increased, particularly for cases vs. controls (72.7% vs. 18.9%, p = 0.002). Multivariate analysis revealed the most important factor for wheezing was RSV hospitalization. Quality of life on the respiratory subscale of the TAPQOL was significantly lower (p = 0.001) and healthcare resource utilization was significantly higher (p<0.001) in cases than controls. This study confirms RSV disease is associated with wheezing in 32-35 wGA infants through 6 years of age.

Nasal and bronchial response to exercise in children with seasonal allergic rhinitis out of the pollen season

BACKGROUND

Allergic rhinitis is a type I allergic disease of the nasal mucosa, and is characterized by paroxysmal sneezing, watery rhinorrhea, and nasal blockage. In seasonal allergic rhinitis subjects, even subthreshold allergen doses have been found to cause inflammatory cell infiltration in the nasal mucosa. This study aimed to investigate the presence of nasal obstructions and symptoms in seasonal allergic rhinitis subjects by assessing an exercise challenge test (ECT) outside of the pollen season.

METHODS

Twenty patients and 20 healthy children who were admitted to the Osmangazi University Medical School Pediatric Allergy Clinic were included in the study in a pollen free season. The total nasal airflow and visual analog scale (for rhinorrhea, nasal congestion, sneezing, and itching) and pulmonary function tests were evaluated before and after each ECT. The nasal airflow and resistance changes were evaluated with anterior rhinomanometry.

RESULTS

Eight patients and one healthy child had nasal obstructions after the ECT. There was a significant difference in the exercise-induced nasal obstructions between the 2 groups (p = 0.02). Eighteen children with exposure to tobacco smoke in the patient and control groups had lower forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and forced expiratory flow 25% to 75% (FEF25-75 ) values than the children without exposure to tobacco smoke.

CONCLUSION

The prevalence of exercise-induced nasal obstruction in children with seasonal rhinitis out of the pollen season is 40%. We showed that minimal persistent inflammation and nasal symptoms can also be diagnosed in rhinitis children in a symptom-free period.

Sensitization to food and inhalant allergens in relation to atopic diseases in early childhood: a birth cohort study

Objectives

A correct interpretation of sensitization to common allergens is critical in determining susceptibility to allergic diseases. The aim of this study was to investigate the patterns of sensitization to food and inhalant allergens, and their relation to the development of atopic diseases in early childhood.

Methods

Children aged 0 through 4 years from a birth cohort in the Prediction of Allergies in Taiwanese Children (PATCH) study were enrolled. Specific IgE antibody against food and inhalant allergens were measured and their association between total serum IgE levels and atopic diseases were assessed.

Results

A total of 182 children were regular followed up at clinics for a four-year follow-up period. The prevalence of food allergen sensitization increased markedly after 6 months of age, reaching up to 47% at 1.5 years of age and then declined significantly to 10% in parallel with a considerable increase in the prevalence of sensitization to inhalant allergens up to 25% at age 4. Food allergen sensitization appeared to be mainly associated with the elevation of serum total IgE levels before age 2. A combined sensitization to food and inhalant allergens had an additive effect on serum IgE levels after age 2, and was significantly associated with the risk of developing atopic diseases at age 4.

Conclusions

Sensitization to food occurs early in life, in parallel with the rising prevalence of sensitization to inhalant allergens at older age. A combined sensitization to food and inhalant allergens not only has an additive increase in serum IgE antibody production but also increases the risk of developing allergic respiratory diseases in early childhood.

Sensitisation patterns and association with age, gender, and clinical symptoms in children with allergic rhinitis in primary care: a cross-sectional study

Background:

Polysensitisation is a frequent phenomenon in patients with allergic rhinitis. However, few studies have investigated the characteristics of polysensitised children, especially in primary care.

Objectives:

This analysis describes the patterns of sensitisation to common allergens and the association with age, gender, and clinical symptoms in children in primary care diagnosed with allergic rhinitis.

Methods:

Cross-sectional data from two randomised double-blind placebo-controlled studies were used to select children aged 6–18 years (n=784) with a doctor's diagnosis of allergic rhinitis or use of relevant medication for allergic rhinitis in primary care. They were assessed for age, gender, specific IgE (type and number of sensitisations), nasal and eye symptom scores.

Results:

In 699 of the 784 children (89%) with a doctor's diagnosis or relevant medication use, a positive IgE test for one or more allergens was found. Polysensitisation (≥2 sensitisations) was found in 69% of all children. Sensitisation was more common in children aged 9–13 than in younger children aged 5–8 years (p=0.03). Monosensitisation and polysensitisation were not significantly different in girls and boys. The severity of clinical symptoms did not differ between polysensitised and monosensitised children, but symptoms were significantly lower in non-sensitised children.

Conclusions:

Polysensitisation to multiple allergens occurs frequently in children with allergic rhinitis in general practice. Overall, clinical symptoms are equally severe in polysensitised and monosensitised children. Treatment decisions for allergic rhinitis should be made on the basis of a clinical history and allergy testing.

Duration of a cow-milk exclusion diet worsens parents' perception of quality of life in children with food allergies

BACKGROUND

In Italy, rigorous studies obtained with specific and validated questionnaires that explore the impact of exclusion diets on health-related quality of life (HRQoL) in children with food allergies are lacking. In this cross-sectional study, we wished to validate the Italian version of a disease-specific quality of life questionnaire, and assess the impact of exclusion diets on the HRQoL in a cohort of Italian children with IgE-mediated food allergies.

METHODS

Children on an exclusion diet for ≥1 food were enrolled consecutively, and their parents completed the validated Italian version of the Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF) and Food Allergy Independent Measure (FAIM).

RESULTS

Ninety-six parents of children aged 0-12 years answered the FAQLQ-PF. The validity of the construct of the questionnaire was assessed by correlation between the FAQLQ-PF and FAIM-PF (r = 0.85). The Italian version of the FAQLQ had good internal consistency (Cronbach's α >0.70). Factors that mainly influenced the HRQoL were older age, severity of food allergy, and the duration of the cow milk-exclusion diet.

CONCLUSIONS

The FAQLQ-PF, validated in Italian, is a reliable instrument. Worse QoL scores were observed among older children, those with severe systemic reactions, and those with a prolonged cow milk-free diet. It is very important to consider the QoL assessment as an integral part of food-allergy management. These results emphasize the need to administer exclusion diets only for the necessary time and the importance of assessment of the HRQoL in these patients.

CD14 gene variants and their importance for childhood croup, atopy, and asthma

BACKGROUND

The CD14 gene has an important role in the detection of inflammatory provoking pathogens and in the ensuing signaling of the innate immune response. We assessed the role of CD14 C-159T, G-1359T in the expression of asthma, croup, and allergy in Canadian school children of ages 6 to 14 years.

METHODS

Children attending schools in a rural community participated in a cross-sectional survey of respiratory health. Following consent, we conducted clinical assessments to collect buccal swabs for genotyping and perform skin prick testing (SPT) to determine atopic status. Genotyping and SPT results were available for 533 and 499 children, respectively. Separate multivariable analyses that included both polymorphisms were conducted for each phenotype.

RESULTS

The prevalence of asthma, allergy, and croup was 18.6%, 22.4%, and 6.6%, respectively. Children with the T/T variant of CD14 G-1359T were more likely to have physician diagnosed asthma (26.8%). Children with C/C variant of CD14 C-159T had a significantly lower prevalence of croup (2.6%). Haplotype analyses of the two CD14 polymorphisms showed that individuals with the T|T haplotype combination were significantly more likely to have asthma (P = 0.014).

CONCLUSIONS

In this study, CD14 variants are important for the expression of croup and asthma but not atopy.

Wheezing in preschool children

Wheezing is a common condition in pediatric practice, it can be defined as a musical sound, high-pitched and continuous, emitting from the chest during breath exhalation. Although almost 50% of children experiences wheeze in the first 6 years of life, only 40% of them will report continued wheezing symptoms after childhood. The classification of wheeze in preschool children is more difficult compared to school aged children. It is based on the onset and duration of symptoms and divided children in three categories: transient early wheezing, non-atopic wheezing and atopic wheezing/asthma. History and physical examination, skin prick test, exhaled nitric oxide, lung function test are the parameter to evaluate children with wheezing. The aim of management of wheezing is to finalize the control of symptoms, reduce exacerbations and improve the quality of life. All guidelines underline the complexity in making a diagnosis of asthma under five years and the need to identify phenotypes that may help paediatricians in the therapeutic choices.

Allergy management in primary care across European countries -- actual status

The standard of care for allergies within a primary care (PC) setting has a strong influence on disease prevention and control, quality of life, and patient satisfaction. The level of knowledge of allergic diseases and the accessibility to regular follow-up are essential. EAACI and IPCRG conducted a survey to evaluate the actual status of care for allergic diseases in PC. Access to allergy and asthma specialist treatment was identified as the greatest 'unmet need'. The average waiting time between a referral and being seen in a public health service is usually >6 weeks. Referring the patients to an 'organ' specialist is much easier compared with referral to an allergist. Most PCPs have access to blood tests for total and specific IgE. Skin prick testing is available in only half of the cases, while provocation tests, allergen quantification in homes, and a dietician service are even less available. 20.6% of practices do not have access to allergy tests at all. Other issues raised were low political or general public awareness, lack of understanding by the patients of their allergic disease, the need to invest in PC, and to achieve sufficient competence at the appropriate level of care.

Allergy Diagnosis in Children and Adults: Performance of a New Point-of-Care Device, ImmunoCAP Rapid

BACKGROUND

: Allergy is a serious problem affecting approximately 1 of 4 individuals. The symptoms with and without allergy etiology are often difficult to distinguish from each other without using an IgE antibody test. The aim of this study was to investigate the performance of a new point-of-care (POC) test for IgE antibodies to relevant allergens in Europe.

METHODS

: IgE antibodies from children and adults with allergies recruited from allergy clinics in Sweden and Spain were analyzed for 10 allergens, suitable for the age groups, using the new POC test and ImmunoCAP laboratory test. The IgE antibody level best discriminating between positive and negative results (the cutoff point) for the different allergens of the POC test and the efficacy of the POC and the ImmunoCAP laboratory tests for diagnosing allergy compared with that of clinical diagnosis were investigated.

RESULTS

: The estimated cutoffs for the different allergens in the POC test ranged from 0.70 to 2.56 kUA/L. Taking into account all positive allergen results in a given patient, the POC test could identify 95% of the patients with allergies. Seventy-eight percent of the allergen-specific physicians' diagnoses were identified and 97% of the negative ones. Most allergens exhibited good performance, identifying about 80% of clinically relevant cases. However, dog, mugwort, and wall pellitory would benefit from improvement.

CONCLUSIONS

: The POC test will be a valuable adjunct in the identification or exclusion of patients with allergies and their most likely offending allergens, both in specialist and general care settings.

Testing children for allergies: why, how, who and when: an updated statement of the European Academy of Allergy and Clinical Immunology (EAACI) Section on Pediatrics and the EAACI-Clemens von Pirquet Foundation

Allergic diseases are common in childhood and can cause a significant morbidity and impaired quality-of-life of the children and their families. Adequate allergy testing is the prerequisite for optimal care, including allergen avoidance, pharmacotherapy and immunotherapy. Children with persisting or recurrent or severe symptoms suggestive for allergy should undergo an appropriate diagnostic work-up, irrespective of their age. Adequate allergy testing may also allow defining allergic trigger in common symptoms. We provide here evidence-based guidance on when and how to test for allergy in children based on common presenting symptoms suggestive of allergic diseases.

Relationships between exhaled nitric oxide and atopy profiles in children with asthma

Purpose

We examined whether fractional exhaled nitric oxide (FeNO) levels are associated with atopy profiles in terms of mono-sensitization and poly-sensitization in asthmatic children.

Methods

A total of 119 children underwent an assessment that included FeNO measurements, spirometry, methacholine challenge, and measurement of blood eosinophil count, serum total IgE, and serum eosinophil cationic protein (ECP). We also examined sensitization to five classes of aeroallergens (house dust mites, animal danders, pollens, molds, and cockroach) using skin prick testing. The children were divided into three groups according to their sensitization profiles to these aeroallergens (non-sensitized, mono-sensitized, and poly-sensitized).

Results

The geometric means (range of 1 SD) of FeNO were significantly different between the three groups (non-sensitized, 18.6 ppb [10.0-34.7 ppb]; mono-sensitized, 28.8 ppb [16.6-50.1 ppb]; and poly-sensitized, 44.7 ppb [24.5-81.3 ppb], P=0.001). FeNO levels were correlated with serum total IgE concentrations, peripheral blood eosinophilia, and serum ECP levels to different degrees.

Conclusions

FeNO levels vary according to the profile of atopy, as determined by positive skin prick test results to various classes of aeroallergens. FeNO is also moderately correlated with serum total IgE, blood eosinophilia, and serum ECP. These results suggest that poly-sensitized asthmatic children may have the highest risk of airway inflammation.

The history of pediatric allergy in Europe - from a working group to ESPACI and SP-EAACI

A Working Group on Pediatric Allergology was formed in 1984, which rapidly developed to become the European Society on Pediatric Allergology and Clinical Immunology (ESPACI) in 1988 with its own journal, Pediatric Allergology and Immunology. ESPACI worked together with the European Academy of Allergology and Clinical Immunology (EAACI) to form a Section of Pediatrics within EAACI (SP-EAACI) in 1996. The ESPACI and the SP-EAACI formally merged in 2001. Within the EAACI organization, the Pediatric Section has continued to grow. The Pediatric Section is working to develop pediatric allergology across Europe, focusing on postgraduate education, facilitating the research agenda and advocating for children and adolescents with allergies.

Parent perceived quality of life is age-dependent in children with food allergy

BACKGROUND

Food allergy in children significantly affects their quality of life. Its impact can be analyzed by quality of life questionnaires.

OBJECTIVES

The aim of our study was to validate the French version of disease-specific questionnaires and to evaluate the quality of life in children with IgE-mediated food allergy.

METHODS

Two validated food allergy-specific questionnaires for quality of life, the parent's and children's forms (FAQLQ-PF and FAQLQ-CF), were translated from English to French and submitted to children with food allergy and their parents. Questionnaires were analyzed in terms of emotional impact, food anxiety, and social and food limitations. NCT 01480427.

RESULTS

Sixty-two parents of children aged 0-12 yrs answered the FAQLQ-PF, and 32 children aged 8-12 yrs the FAQLQ-CF. Construct validity of both questionnaires was assessed by correlation between the FAQLQs and FAIM (r = 0.85 and 0.84, respectively). Both FAQLQs had good internal consistency (Cronbach's α = 0.748 and 0.67, respectively). Young children (0-3 yrs old) showed better quality of life scores than older children (FAQLQ-PF global score: p = 0.02). Worse scores were also shown among children with previous severe systemic reactions (FAQLQ-PF global score: p = 0.039), the ones with an allergic mother (FAQLQ-PF global score: p = 0.002), or allergic siblings (FAQLQ-PF emotional impact score: p = 0.034), the ones with multiple food allergy (more than 1 food) (FAQLQ-PF anxiety score: p = 0.04) and among the girls (FAQLQ-CF global score: p = 0.031).

CONCLUSION

Older children, the ones with severe systemic reactions, or with mothers or siblings also affected by allergies, as well as girls, and children with multiple food allergies show worse quality of life scores.

Early Pollen Sensitization in Children Is Dependent upon Regional Aeroallergen Exposure

Introduction. Aeroallergen sensitization occurs at an earlier age than previously noted. The purpose of this paper was to identify which pollens cause early sensitization in young children presenting with rhinitis symptoms. Methods. This paper was a retrospective analysis of skin test results from 2- to 8-year-old patients presenting with a history consistent with allergic rhinitis. Patients were tested to aeroallergens common to the Great Basin along with a histamine and saline control. Pollen counts were obtained from a Reno, NV-certified counting station. Results. 123 children less than 8 years of age were identified. Over 50% of these children were sensitized to at least one aeroallergen. Chemopodaciae, timothy, alfalfa, black walnut, olive, mountain cedar and willow were predominating sensitizing aeroallergens of the Great Basin Region. Pollen counts were notable for a early spring peak for the tree season, grass season in May and weed season in August. Pollen levels continued to November at low levels. Discussion. Aeroallergens causing early sensitization differed from those which had predominately been reported in other regions of the United States. Pediatric allergists should consider performing a local review of sensitizing aeroallergens in their region to assist with identification and management of allergic rhinitis in their youngest patients. Please make style changes as appropriate.

Predicting allergic disease at age four using an atopy predisposition score at age two: the application of item response theory

When defining allergic outcomes in epidemiology studies, results of the skin prick test (SPT) panel are often dichotomized as positive/negative or categorized based on the number of positive responses. Item response theory (IRT) models, however, may prove to be a better alternative with the ability to generate scores that account for both type and number of positive SPTs. IRT was applied to SPT responses administered to 537 children at age two to determine predictability of allergic disease at age four. The children received SPTs to 15 aeroallergens and two foods. Atopy predisposition scores were obtained from the IRT model using the posterior distribution of the latent trait, atopy. These scores were used to predict persistent wheeze, rhino-conjunctivitis, and eczema at age four. Results were compared to the dichotomized and categorical (positive to ≥2, positive to one, vs. negative to all allergens) SPT variables. At age two, 39% of children had at least one positive SPT. All three allergic disease outcomes were significantly associated with IRT atopy scores: persistent wheeze odds ratio (OR) = 1.7 (95% confidence interval (CI): 1.2, 2.3); rhino-conjunctivitis OR = 1.7 (95% CI: 1.2, 2.3); eczema OR = 1.6 (95% CI: 1.2, 2.3). In contrast, rhino-conjunctivitis was the only outcome significantly associated with the dichotomized SPT variable with an OR = 1.9 (95% CI: 1.2, 3.0). For the categorical SPT variable, all three allergic symptoms were significantly associated with positive to ≥2 allergens compared to negative to all, but no difference was observed between those with positive to one compared to negative to all. The IRT model proved to be an informative methodology to assess the predictability of early SPT responses and identify the allergens most associated with atopy predisposition.

Agreement of specific IgE and skin prick test in an unselected cohort of two-year-old children

The objective of this study was to evaluate the agreement between specific IgE (sIgE) and skin prick test (SPT), and the possible association between total IgE concentration and allergy-related disorders, when performed in an unselected cohort of 353 two-year olds. Median total IgE was within the reference value for two-year-old children regardless of the presence or absence of allergy-related disorders. 18.7% of the children had one or more positive reactions to SPT and/or sIgE in a panel of 12 allergens. Agreement between SPT and sIgE was variable, being best for peanut and poorest for milk.

CONCLUSION

In young children total IgE is of limited value when evaluating allergy-related disorder. The lack of agreement among the positive tests of the sIgE and SPT for some allergens imply that these tests should not be used interchangeably, and both tests should probably be used complementarily when diagnosing atopic sensitization in small children.

Ovomucoid (Gal d 1) specific IgE detected by microarray system predict tolerability to boiled hen's egg and an increased risk to progress to multiple environmental allergen sensitisation

BACKGROUND

Egg allergy is a very common finding in early childhood. Detecting hen's egg (HE) allergy outgrowing and reintroduction of food containing egg is a task for the allergist.

OBJECTIVE

We sought to evaluate the suitability of boiled egg food challenge compared with IgE to allergenic molecules from HE white using a microarray system.

METHOD

Sixty-eight children referring to our centre by the family paediatricians for a suspected egg allergy were enrolled. Patients underwent double-blind, placebo-controlled food challenge with boiled and raw eggs. Challenge outcomes were compared with skin tests performed using egg white and yolk commercial extracts, to prick-prick test with boiled and raw egg white and yolk, total IgE, egg white specific IgE detected using ImmunoCAP and IgE to egg allergens available on the immunosolid phase allergen chip (ISAC) 103 microarray.

RESULT

Nineteen subjects (28%) were reactive to both raw and boiled egg, 14 (20.5%) to raw egg only and 35 (51.4%) tolerated both boiled and raw egg. Efficiency analysis was carried out using both raw and boiled egg challenges as gold standard. Forty four of 47 Gal d 1 negative patients tolerated boiled egg (94%). Conversely, 20 of 21 Gal d 1 positive patients reacted to raw egg (95%). None of the other tests was able to discriminate patients' response to HE challenge. Furthermore, Gal d 1 positivity seems to lead to broader environmental allergen IgE sensitization.

CONCLUSION AND CLINICAL RELEVANCE

The Gal d 1 IgE reactivity appears to be a very good predictor of HE clinical allergy. Gal d 1 positive children have a high frequency of HE allergy, whereas Gal d 1 negative children have a high frequency of tolerance to boiled egg. Multiple specific IgE detection by means of ISAC improves the diagnostic approach in HE allergic children, disclosing other food and inhalant allergic sensitizations, anyhow requiring a comprehensive clinical evaluation.

Dietary treatment of cows' milk protein allergy in childhood: a commentary by the Committee on Nutrition of the French Society of Paediatrics

The diagnosis of cows' milk protein allergy (CMPA) requires first the suspicion of diagnosis based on symptoms described in the medical history, and, second, the elimination of cows' milk proteins (CMP) from the infant's diet. Without such rigorous analysis, the elimination of CMP is unjustified, and sometimes harmful. The elimination diet should be strictly followed, at least until 9–12 months of age. If the child is not breast fed or the mother cannot or no longer wishes to breast feed, the first choice is an extensively hydrolysed formula (eHF) of CMP, the efficacy of which has been demonstrated by scientifically sound studies. If it is not tolerated, an amino acid-based formula is warranted. A rice protein-based eHF can be an alternative to a CMP-based eHF. Soya protein-based infant formulae are also a suitable alternative for infants >6 months, after establishing tolerance to soya protein by clinical challenge. CMPA usually resolves during the first 2–3 years. However, the age of recovery varies depending on the child and the type of CMPA, especially whether it is IgE-mediated or not, with the former being more persistent. Once the child reaches the age of 9–12 months, an oral food challenge is carried out in the hospital ward to assess the development of tolerance and, if possible, to allow for the continued reintroduction of CMP at home. Some children with CMPA will tolerate only a limited daily amount of CMP. The current therapeutic options are designed to accelerate the acquisition of tolerance thereof, which seems to be facilitated by repeated exposure to CMP.

[Clinical manifestations of atopy in children up to two years of age]

BACKGROUND/AIM

Atopic diseases such as atopic dermatitis, allergic rhinitis and asthma have had increased prevalence during the past decade and nowadays occur in every third child in developed countries. The aim of the study was to determine frequency and type of atopic diseases at the age of two, as well as the importance the total IgE antibodies concentrations have in diagnosis and prognosis of the disease.

METHODS

The study involved 175 children up to two years of age. Allergy-like symptoms were found after surveying their parents and pediatric medical records. Using the fluorescence immunossay (FIA) method, total IgE antibodies concentrations and specific IgE antibodies (Phadiatop infant) were determined on an Immunocap 100 Dyagnostic System.

RESULTS

One or more allergy-like symptoms accounted for 57.7% of findings in children under the age of two, whilst in 19.4% the existence of IgE-related allergic diseases was found. Atopic diseases usually have clinical manifestations of atopic dermatitis (11.4%), IgE-bound wheezing/asthma (10.8%) and food allergies (7.4%), and to much lesser extent those of allergic rhinitis (3.4%) and urticaria (1.7%). The significantly higher total IgE antibodies concentrations were found in children with allergy-like symptoms (p < 0.0005) (cut-off 15.15 kU/L, sensitivity 76.5% specificity 71.6%).

CONCLUSION

Almost 20% of two-year-old children have any of clinically manifested allergic diseases, with atopic dermatitis and IgE wheeze/asthma being predominant. The higher total IgE antibodies concentration is a good marker for sensitization in children with allergy-like symptoms.

Aeroallergen sensitization in wheezing children from rosario, Argentina

Background

Wheezing is a highly frequent symptom in infants and children. Its major causes are respiratory infections and bronchial asthma. In this context, allergen sensitization plays an important role, and it can be detected by a skin prick test, a safe and effective technique that can be easily performed on any age-group. To assess the prevalence of aeroallergen sensitization in a pediatric population with recurrent episodes of wheezing.

Materials and Methods

Cross-sectional study that evaluated 100 patients, 50 (50%) girls and 50 (50%) boys, from 6 months to 10 years. These children had consulted frequently at the Allergy and Immunology Division of the Eva Perón School Hospital due to recurrent episodes of wheezing. Skin prick test were performed on all of them and also on 20 healthy children.

Results

Overall, 58% of the patients presented sensitization to dust mite, 13% to pollen, 9% to epithelium, 8% to fungi, 6% to cockroach, and 1% to soybean hull. Overall, 60% of the patients were positive to at least one of the extracts, and we observed a significant and gradual increase in the frequency of sensitization in older age-groups (P < 0.005). This increase persisted when analyzing separately the dust mite group and the pollen group. None of the cases presented any adverse local or systemic reaction during the procedure or the following 24 hours after the procedure. The 20 individuals in the control group turned out negative when tested.

Conclusions

This study found high aeroallergen sensitization prevalence in a pediatric population with recurrent episodes of wheezing examined in the Allergy and Immunology Division of the Eva Perón School Hospital, which is in the southern area of the province of Santa Fe in Argentina.

An explorative study of low levels of allergen-specific IgE and clinical allergy symptoms during early childhood

BACKGROUND

Early identification of children at risk for later development of allergic disease is essential for early intervention and initiation of proper treatment and management.

OBJECTIVE

To investigate the relationship between low levels (0.1-0.7 kU(A) /l) of IgE sensitization to food and inhalant allergens and symptoms of eczema, rhinitis, and asthma from birth to 5 years of age.

METHODS

Children (268) were followed prospectively from birth to 5 years of age with physical examinations and measurements of s-IgE at 6, 12, 24, and 60 months of age.

RESULTS

Seventy-four percent of the children with low levels of s-IgE to egg and/or milk at the age of 6 months were still sensitized to one or more allergens at age 2 years. Eighty-four percent of the children with low levels of s-IgE to any of the studied allergens at 12 months of age were still sensitized at age 5. The low levels of egg and milk s-IgE also significantly increased the risk for eczema at the same age and also increased the risk for eczema at 2 years of age.

CONCLUSION

Low levels of s-IgE can be detected from the age of 6 months and are related to further IgE sensitization. The low levels seem to be of importance for both the association to present symptoms and for prediction of future allergic symptoms, especially eczema during early infancy. A detectable s-IgE level, albeit low, could be a clear signal that the immune system is alerted and should be followed.

Sensitization patterns to food and inhalant allergens in childhood: a comparison of non-sensitized, monosensitized, and polysensitized children

The clinical interpretation of children sensitized to numerous allergens is challenging. We examined differences between children sensitized to zero, one, or more allergens. This was a retrospective analysis of all specific IgE tests in children 0-18 yrs of age sent to our laboratory by general practitioners and hospital-based specialists for allergy testing between 1990 and 2003. Of all 9044 children tested, 5439 (60.1%) were not sensitized to any of the aeroallergens or food allergens tested. Three thousand six hundred and five children (39.9%) had one or more positive specific IgE tests, 1120 of which (31.1%) were monosensitized (73% to aeroallergens and 27% to food allergens), 1709 (47.4%) were sensitized to two to four allergens, and 776 (21.5%) to five or more allergens (polysensitization). Polysensitization was more common in children 4-11 yrs of age (24.8%) than in younger (18.7%) or older children (18.3%, p < 0.001), and more common in boys (9.8%) than in girls (7.3%, p < 0.001). Median total IgE values increased with increasing number of positive specific IgE tests (p < 0.001). House dust mite more commonly showed monosensitization (22.2%) than other aeroallergens (grass pollen 10.5%, tree pollen 3.6%, cat 2.9%, and dog 1.5%); cow's milk (27.6%) more commonly than other food allergens (hen's egg 9.7%, peanut 4.6%, wheat 0.8%, soy 0.7%). Between 55.7% (cow's milk) and 87.9% (soy) of children sensitized to food were cosensitized to aeroallergens, while only 25.4% (house dust mite) to 39.5% (dog) of children sensitized to aeroallergens were cosensitized to food. Polysensitization is common in children, in particular in boys. It is most common in school-aged children. The strong association with total serum IgE values and the striking cosensitization between biologically unrelated allergens suggest that polysensitization is the expression of a distinct clinical, more severe, atopic phenotype, and not of biologic cross-reactivity to similar allergens.

Maternal immunization to modulate the development of allergic response and pathogen infections

This article reviews recent experimental approaches of preventive strategies regarding allergy and infections by pathogens, particularly in early childhood, by targeting maternal immunomodulation. Basic research is essential to understand maternal vaccination as a strategy to control allergic disease and bacterial and viral infections; thus, providing support for future translational research. The environmental stimuli and host genetic factors, along with maternal influences in early life when immune systems are developing and during postnatal life, are essential for the decision between tolerance induction or allergen sensitization. Maternal immunomodulation strategies should serve as a challenge when attempting to halt the spread of allergy responses and viral infections, until the innate and adaptive arms of the immune system of the neonates are competent.

Effects of latex avoidance on latex sensitization, atopy and allergic diseases in patients with spina bifida

BACKGROUND

Ten years ago, avoidance measures such as the performance of latex-free operations were implemented in children with spina bifida. Since then, latex sensitization and latex allergy have decreased in this high-risk group.

OBJECTIVE

To study the effect of primary latex-free prophylaxis on the prevalence of allergic diseases and atopy as a marker for sensitization spreading in children with spina bifida.

METHODS

One hundred and twenty children with spina bifida born after the introduction of latex-free prophylaxis and operated on under latex-free conditions ('current group') were examined for latex sensitization, latex allergy, sensitization to aero- and food allergens and allergic diseases. Results were compared to a 'historic' (not latex-free operated) group of children with spina bifida and comparable age (n = 87) and to a recent sample of children from the general population (n = 12,403).

RESULTS

In comparison with the 'historic group', latex sensitization (55% vs 5%, P < 0.001) and latex allergy (37% vs 0.8%, P < 0.001) were significantly reduced in the 'current group'. Furthermore, a significant reduction could be demonstrated for sensitization to aeroallergens (41.4% vs 20.8%, P = 0.001) and for allergic diseases (35% vs 15%, P = 0.001). The prevalence for atopy, sensitization to aero-/foodallergens and for allergic diseases in children of the 'current group' was similar to those in children of the weighted population sample.

CONCLUSIONS

Latex avoidance in children with spina bifida prevents latex sensitization and latex allergy. Additionally, it also seems to prevent sensitization to other allergens and allergic diseases which might be explained by the prevention of sensitization spreading.

Health-care cost reduction resulting from primary-care allergy testing in children in Italy

Background

Allergy places a considerable cost burden on society. Specific immunoglobulin E (spIgE) testing may improve the management of allergy patients. There is therefore a reason to quantify the economic consequences of the use of spIgE testing in the diagnosis of allergic conditions.

Methods

The expected costs of spIgE testing versus no-testing were calculated using a clinical decision model based on a prospective clinical trial performed in primary care.

Results

The expected costs per patient over 2 years decreased from 802 euros in the "no-test strategy" to 560 euros in the spIgE "test strategy". Cost savings persisted even after assumptions about the prevalence of allergy and the prices of medications were changed. The "test strategy" increased the percentage of patients correctly diagnosed from 54 to 87%.

Conclusions

spIgE testing of children with respiratory and/or skin problems in primary care in Italy reduces overall costs to society. These cost savings mostly result from a reduction in the use of medications, particularly corticosteroids. The study indicates that spIgE testing of all children with respiratory and/or skin symptoms would be a cost-effective strategy.

Can sensitization to aeroallergens disappear over time in children with allergic disease?

BACKGROUND

Remittance of aeroallergen sensitization has been shown in population-based studies, but there is a common perception that sensitization to aeroallergens rarely if ever disappears in children with allergic disease.

METHODS

We retrospectively reviewed all specific IgE tests carried out in children aged 0-18 years at our hospital laboratory over a 14-year period. Of 3115 children sensitized to one or more aeroallergens, 244 (7.8%) were retested after a mean (SD) period of 45 (28) months at their physician's discretion.

RESULTS

Disappearance of sensitization to individual aeroallergens did occur, with remittance rates ranging from 3.1% for house dust mite to 17.5% for cat. However, complete remittance of aeroallergen sensitization was found in only one subject. In up to 35% of cases, remittance of sensitization was offset by the appearance of one or more new aeroallergen sensitizations. Remittance was only observed in children sensitized to multiple allergens (with a median of 3 aeroallergen sensitizations), and their median degree of sensitization was low (median 2.1 kU/L).

CONCLUSION

Aeroallergen sensitization can disappear in children with allergic disease, but only in polysensitized individuals. Complete remittance of sensitization to aeroallergens is rare in symptomatic children.

Prediction of atopy in the first year of life using cord blood IgE levels and family history

We assessed correlations of total and specific cord-blood IgE (cIgE) levels with allergic symptoms in the first year of life. cIgE levels were determined by an immunoassay test in full-term neonates. This is a prospective study in which a questionnaire was used after birth, and at 6 and 12 months of age. We used multiple logistic regression models to assess the association between the family history of atopy and the incidence of allergy. The infants were divided in to groups based on the cIgE level (Group 1 < 0.1 IU/ml, n = 65; Group 2 0.1-0.5 IU/ml, n = 63; Group 3 > 0.5 IU/ml, n = 45). We found the symptoms of atopy in 26 children in Group 1 (40%), 30 (47.6%) in Group 2, and 17 (37.7%) in Group 3; the percentage of atopic diseases was in significantly different among the three groups. No association between a high total cIgE and specific cIgE with atopy family history and the outcome of atopic diseases was discovered. We conclude that neither total nor specific cIgE level with atopy family history can be used as an indicator to single out high risk infants.

Microarrays: Molecular allergology and nanotechnology for personalised medicine (II)

Progress in nanotechnology and DNA recombination techniques have produced tools for the diagnosis and investigation of allergy at molecular level. The most advanced examples of such progress are the microarray techniques, which have been expanded not only in research in the field of proteomics but also in application to the clinical setting. Microarrays of allergic components offer results relating to hundreds of allergenic components in a single test, and using a small amount of serum which can be obtained from capillary blood. The availability of new molecules will allow the development of panels including new allergenic components and sources, which will require evaluation for clinical use. Their application opens the door to component-based diagnosis, to the holistic perception of sensitisation as represented by molecular allergy, and to patient-centred medical practice by allowing great diagnostic accuracy and the definition of individualised immunotherapy for each patient. The present article reviews the application of allergenic component microarrays to allergology for diagnosis, management in the form of specific immunotherapy, and epidemiological studies. A review is also made of the use of protein and gene microarray techniques in basic research and in allergological diseases. Lastly, an evaluation is made of the challenges we face in introducing such techniques to clinical practice, and of the future perspectives of this new technology.