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This article discusses a study conducted on teenagers from the PARIS birth cohort to assess the association between basal serum tryptase (bST) levels and various allergy-related outcomes. The study found that higher bST levels were associated with sensitization, allergic morbidity, and lower control of allergic asthma. The results suggest that bST levels could be a potential tool for predicting and stratifying allergic phenotypes in early life. The study provides valuable insights into the relationship between bST levels and allergies in teenagers. [Extracted from the article]

Background: Atopic dermatitis (AD) is rising globally, with genetics and environmental factors both playing crucial roles. Dietary habits during pregnancy are linked to children's allergic disease risk. However, limited studies have explored the association between maternal vegetarian diets during pregnancy and child AD. Therefore, this study aimed to examine the relationship between maternal vegetarian diets during pregnancy and the occurrence of AD in children. Methods: In this study, the Taiwan Birth Cohort Study (TBCS) database was used, comprising a representative national birth cohort of infants born in Taiwan in 2005. Of 24,200 mother–child pairs in the database, 20,172 completed face‐to‐face interviews at 6 and 18 months. Employing a 1:10 matching strategy based on maternal age, education level, and child sex, 408 mothers who followed a vegetarian diet during pregnancy were matched with 4080 nonvegetarian mothers. This resulted in a final dataset of 4488 subjects. Logistic regression was used to explore the association between maternal vegetarian diets during pregnancy and the occurrence of AD in children. Results: Among the TBCS participants, there were 292 (1.8%) mothers who adhered to lacto‐ovo vegetarianism and 116 (0.7%) mothers who adhered to veganism, totaling 408 (2.4%) vegetarians during pregnancy. Compared to children of nonvegetarian mothers, children of mothers who followed a vegetarian diet during pregnancy showed a lower risk of developing AD before 18 months of age (OR = 0.65, 95% CI = 0.45–0.93, p = 0.018). Conclusion: This study suggests that a vegetarian diet during pregnancy may lower the risk of AD in children. It is essential to carry out long‐term follow‐up to fully understand the impact of a mother's diet on allergic conditions. [ABSTRACT FROM AUTHOR]

Background: Atopic march is defined as the progression from atopic dermatitis (AD) during early life to other allergic diseases in later childhood. In a nationwide birth cohort study, the Japan Environment and Children's Study, we investigated the association of bathing habits, which are known to affect skin conditions, for infants with their later development of allergic diseases. Methods: Pregnant women who lived in 15 designated regional centers throughout Japan were recruited. We obtained information on bathing habits for their 18‐month‐old infants and the prevalence of allergic diseases when they were aged 3 years. Results: Data for 74,349 children were analyzed. Most 18‐month‐old infants were bathed or showered almost every day. When they were divided into four groups according to the frequency of soap use during bathing (every time, most of the time, sometimes, and seldom), the risk of AD later at age 3 was shown to increase in association with a decreasing frequency of soap use [most of the time: adjusted odds ratio (aOR) 1.18, 95% confidence interval (CI) 1.05–1.34; sometimes: aOR 1.72, 95% CI 1.46–2.03; seldom: aOR 1.99, 95% CI 1.58–2.50], compared with soap use every time during bathing at 18 months of age. Similar results were obtained for food allergy but not for bronchial asthma. Conclusions: Frequent soap use when bathing 18‐month‐old infants was associated with a decreased risk of them developing allergic diseases at age 3. Further well‐designed clinical studies are warranted to determine an effective bathing regimen for preventing the development of allergic diseases. [ABSTRACT FROM AUTHOR]

Background: There is currently no insight into biomarkers that can predict the onset of pediatric atopic dermatitis (AD). Methods: Nested in a prospective birth cohort study that examined the occurrence of physician‐diagnosed AD in 300 children, 44 random children with onset of AD in the first year of life were matched on sex and season of birth with 44 children who did not develop AD. Natural moisturizing factor (NMF), corneocyte surface protrusions, cytokines, free sphingoid bases (SBs) of different chain lengths and their ceramides were analyzed from tape strips collected at 2 months of age before onset of AD using liquid chromatography, atomic force microscopy, multiplex immunoassay, and liquid chromatography mass spectrometry, respectively. Results: Significant alterations were observed for four lipid markers, with phytosphingosine ([P]) levels being significantly lower in children who developed AD compared with children who did not (median 240 pmol/mg vs. 540 pmol/mg, p < 0.001). The two groups of children differed in the relative amounts of SB of different chain lengths (C17, C18 and C20). Thymus‐ and activation‐regulated chemokine (TARC/CCL17) was slightly higher in children who developed AD, whereas NMF and corneocyte surface texture were similar. AD severity assessed by the eczema area and severity index (EASI) at disease onset was 4.2 (2.0;7.2). [P] had the highest prediction accuracy among the biomarkers (75.6%), whereas the combination of 5 lipid ratios gave an accuracy of 89.4%. Conclusion: This study showed that levels and SB chain length were altered in infants who later developed AD, and that TARC/CCL17 levels were higher. [ABSTRACT FROM AUTHOR]

Background: Maternal vitamin D status during pregnancy has been linked with the risk of atopic dermatitis (AD) in children, while the results were inconsistent. The objective of this study was to assess the potential association. Methods: Serum 25‐hydroxyvitamin D (25(OH)D) levels were measured in pregnant women from the birth cohort MKFOAD. Infant AD was diagnosed according to Williams' criteria. Multivariate logistic regression model was used to examine the association of maternal serum 25(OH)D levels in the first, second, and third trimester of gestation with the risk of infant AD at first year of age. Results: In total, 121 (26.5%) of 456 infants developed AD prior to 1 year of age. In general, higher maternal serum 25(OH)D levels throughout pregnancy were associated with increased risks of AD in infants prior to 1 year of age in multivariate logistic regression models, with borderline statistical significance in the first (per ln unit increase: adjusted OR = 1.93, 95% CI: 0.96, 3.88) and second (per ln unit increase: adjusted OR = 1.72, 95% CI: 0.93, 3.19) trimester. Multivariate logistic regression models using categorical variables of maternal 25(OH)D levels by tertiles showed similar results: Infants born to mothers with serum 25(OH)D levels in the highest tertile had higher risk of AD than those with 25(OH)D in the lowest tertile. Conclusions: The present study found some evidence supporting that higher maternal 25(OH)D levels during pregnancy increased the risk of infant AD. However, the clinical implication of the findings should be limited for those with blood levels over the recommendations. [ABSTRACT FROM AUTHOR]

Background: Skin barrier functions develop after birth and may be related to skin disorders in infants. We aimed to assess associations between dynamic trends of four skin barrier functional parameters in early life with infant atopic dermatitis (AD). Methods: Based on the prospective cohort MKNFOAD (NCT02889081), we examined transepidermal water loss (TEWL), stratum corneum hydration (SCH), skin pH, and sebum content at five anatomical sites (cheek, forehead, forearm, abdomen, and lower leg) in 418 term infants at birth, 42 days, and 6 months. Trend differences by sex and association with AD at age 1 year were tested using variance analyses. Associations of the parameters with AD risk were tested using discrete time survival analysis, adjusting extensive covariates including parental history of allergy, infant's sex, birth weight (kg), and delivery mode. Odds ratios (ORs) and 95% confidence interval (CIs) were reported. Results: Overall TEWL and SCH appeared trends of increase while skin surface pH and sebum content showed trends of decrease within the first six postnatal months. Sex differences were significant for sebum content only (p < 0.001). After adjustment for parental and children covariates, cheek TEWL at birth (OR = 1.26, 95% CI 1.00–1.57, p = 0.045) and 42 days (OR = 1.52, 95% CI 1.17–1.97, p = 0.002) were significantly associated with increased AD risk. Associations were not observed between SCH, skin pH, and sebum content at birth or 42 days with AD. Conclusions: Skin barrier functions of Chinese term infants varied nonlinearly after birth. Higher postnatal TEWL levels in early life indicate higher risk of early‐onset AD. [ABSTRACT FROM AUTHOR]

Background: Previous studies have investigated the natural course of cow's milk allergy (CMA) and development of atopic diseases into adolescence. Studies with long‐term follow‐up into adulthood are lacking. The aim of this study was to investigate (a) the natural course of CMA in a 1‐year birth cohort of Danish children from birth until 15 and 26 years of age and (b) the development of atopic diseases in a group of children with CMA (group A) compared to a random sample of 276 children from the same birth cohort (group B). Methods: A birth cohort of 1749 newborns was investigated prospectively for the development of CMA and atopic diseases. During the first year of life and at 18 months and 3, 5, 10, 15, and 26 years of age, questionnaire‐based interviews, physical examination, skin prick tests, and specific IgE testing, and from 10 years also spirometry, were carried out. Results: Thirty‐nine (2.2%) were diagnosed with CMA. The recovery rate was 87%, 92%, and 97% at 3, 5, and 26 years of age. Compared to group B, group A had significantly (P <.05) higher prevalence of asthma and rhinoconjunctivitis at 15 years of age, and at 26 years of age, group A had significantly higher prevalence of asthma and atopic dermatitis. The follow‐up rate was 85% (A) and 70% (B). Conclusion: CMA has a good prognosis regarding recovery rate. However, CMA, especially IgE‐mediated, in early childhood predicts a high prevalence of atopic diseases into adulthood. [ABSTRACT FROM AUTHOR]

Background: An association has been reported between early life Staphylococcus aureus nasal carriage and higher risk of childhood eczema, but it is unclear whether this relationship is causal and associations with other bacterial species are unclear. Objective: To examine the associations of early life nasal and nasopharyngeal bacterial carriage with eczema phenotypes, and the direction of any associations identified. Methods: Among 996 subjects of a population‐based prospective cohort study, nasal swabs for Staphylococcus aureus, and nasopharyngeal swabs for Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae were collected and cultured from age 6 weeks to 6 years. Never, early, mid‐, late transient and persistent eczema phenotypes were identified from parental‐reported physician‐diagnosed eczema from age 6 months until 10 years. Multinomial regression models and cross‐lagged models were applied. Results: Staphylococcus aureus nasal carriage at 6 months was associated with an increased risk of early transient and persistent eczema (OR (95% CI): 2.69 (1.34, 5.39) and 4.17 (1.12, 15.51)). The associations between Staphylococcus aureus nasal carriage and eczema were mostly cross‐sectional, and not longitudinal. No associations of Staphylococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenza nasopharyngeal bacterial carriage with eczema and eczema phenotypes were observed (OR range (95% CI): 0.71 (0.35, 1.44) to 1.77 (0.84, 3.73)). Conclusions: Early life Staphylococcus aureus nasal carriage, but not Staphylococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenza nasopharyngeal carriage, was associated with early transient and persistent eczema. Staphylococcus aureus nasal carriage and eczema were mostly cross‐sectionally associated, and not longitudinally, making a causal relationship in either direction unlikely. [ABSTRACT FROM AUTHOR]

Background: Maternal folate status is linked with the risk of allergic disorders including atopic dermatitis (AD) in children, but findings remain inconclusive. We aim to assess the relationship between maternal folate status in early gestation and early‐onset infant AD, based on a prospective mother‐child cohort study. Methods: Pregnant women were recruited at 12‐14 weeks of gestation. Red blood cell folate (RBC folate) and serum folate concentrations were examined at enrollment. Periconceptional folic acid supplementation was investigated through a self‐administered questionnaire. The primary outcome was AD incidence before 6 months of age, diagnosed according to Williams' criteria. Multivariate logistic regression was used to evaluate associations of maternal folate status with infant AD by adjusting parental and child covariates. Results: In total, 107 (23.4%) of 458 infants developed AD before 6 months, with more male infants affected (P =.002). Higher maternal RBC folate levels (per 100 ng/mL) were associated with an increased risk of AD (adjusted odds ratio [aOR] 1.16, 95% confidence interval [CI] 1.04‐1.31). An RBC folate level ≥620 ng/mL was associated with increased infant AD by 91% (aOR 1.91, 95% CI 1.09‐3.36). However, associations were not observed for maternal serum folate at early gestation or periconceptional folic acid supplement intakes. Conclusions: We provide the first evidence that higher maternal RBC folate concentrations during early gestation are associated with increased early‐onset infant AD. Our findings support the importance of maintaining appropriate folate levels during the periconceptional period to reduce the risk of AD in infants. [ABSTRACT FROM AUTHOR]

Background: Data addressing short‐ and long‐term respiratory morbidity in moderate‐late preterm infants are limited. We aim to determine the incidence of recurrent wheezing and associated risk and protective factors in these infants during the first 3 years of life. Methods: Prospective, multicenter birth cohort study of infants born at 32+0 to 35+0 weeks' gestation and followed for 3 years to assess the incidence of physician‐diagnosed recurrent wheezing. Allergen sensitization and pulmonary function were also studied. We used multivariate mixed‐effects models to identify risk factors associated with recurrent wheezing. Results: A total of 977 preterm infants were enrolled. Rates of recurrent wheezing during year (Y)1 and Y2 were similar (19%) but decreased to 13.3% in Y3. Related hospitalizations significantly declined from 6.3% in Y1 to 0.75% in Y3. Independent risk factors for recurrent wheezing during Y2 and Y3 included the following: day care attendance, acetaminophen use during pregnancy, and need for mechanical ventilation. Atopic dermatitis on Y2 and male sex on Y3 were also independently associated with recurrent wheezing. Palivizumab prophylaxis for RSV during the first year of life decreased the risk or recurrent wheezing on Y3. While there were no differences in rates of allergen sensitization, pulmonary function tests (FEV0.5) were significantly lower in children who developed recurrent wheezing. Conclusions: In moderate‐to‐late premature infants, respiratory symptoms were associated with lung morbidity persisted during the first 3 years of life and were associated with abnormal pulmonary function tests. Only anti‐RSV prophylaxis exerted a protective effect in the development of recurrent wheezing. [ABSTRACT FROM AUTHOR]

Abstract: Background: Several genetic variants have been associated with the susceptibility to allergic disease in adults, but it remains unclear whether these genetic variants are also associated with the onset of allergic disease early in life. The aim of this study was to develop a genetic risk score (GRS) for allergy based on findings in adults and study its predictive capacity for allergy in children. Methods: A GRS was constructed based on 10 SNPs previously associated with allergies in adults. The GRS was tested in children who participated in a population‐based newborn cohort (WHISTLER) and were followed from birth to school age. Logistic regression analysis was used to study the association between the GRS and the parental‐reported allergies at age 5 (based on a reported allergy to ≥1 of the following allergens: pollen, house dust mites, or pets). A Cox regression model was used to study the association between GRS and a physician‐diagnosed allergy during follow‐up (allergic conjunctivitis, allergic rhinitis, and eczema/dermatitis). Cohen's kappa coefficient was calculated to study the agreement between physician‐diagnosed allergy and parental‐reported allergy at age 5. Results: The GRS was significantly associated with parental‐reported allergy (odds ratio: 15.9, 95% confidence interval (CI): 1.07‐233.73) at age 5, as well as with a physician‐diagnosed allergy during follow‐up (hazard ratio: 1.89, 95% CI: 1.05‐3.41). The overall agreement between physician‐diagnosed and parental‐reported allergies was 70.5% (kappa: 0.10, 95% CI: 0.03‐0.18). Conclusions: An adult‐derived GRS for allergy predicts the risk of developing allergies in childhood. [ABSTRACT FROM AUTHOR]

Background Evidence linking maternal psychosocial stress during pregnancy to subsequent child atopic dermatitis (AD) is growing, but the definition of AD is diverse and results are inconsistent. We aimed to analyze the relationship between stress and AD using alternative measurements of stress and AD. Methods In the Ulm SPATZ Health Study, chronic stress and symptoms of anxiety and depression were assessed by standardized self-reported questionnaires in 934 mothers of singletons following delivery in Ulm, Germany, from 04/2012-05/2013. Maternal hair cortisol concentrations (HCCs, n = 626) at childbirth and the cumulative incidences of parent-reported child AD symptoms, parent-, and pediatrician-reported AD diagnoses were assessed until age 2 years (n = 787). Overall, 205 dermatologic examinations were performed in 167 children showing AD symptoms. Crude and adjusted risk ratios (RR, aRR) with 95% confidence intervals were estimated. Results Maternal stress and anxiety were associated with child AD symptoms by trend (RR and aRR: 1.5 (1.0,2.3) for the highest vs. the lowest quarter of chronic stress; aRR: 1.4 (1.0,2.0) for possible anxiety symptoms vs. no symptoms). No relationship was found between stress or related constructs and AD diagnoses nor could we show consistent associations between maternal HCC and child AD. However, a higher RR of child AD was evident in families not yet affected by AD in siblings given maternal depressive symptoms, examined in the crude model. Conclusions Stress measurements or related constructs are linked to AD symptoms, but association with AD diagnoses is limited. The reason for this divergence still needs further research. [ABSTRACT FROM AUTHOR]

Background Little is known about the effect of postnatal maternal psychologic problems on the development of childhood atopic disorders. Objectives To assess the association between early life maternal psychologic problems and atopic dermatitis ( AD) in children in a national birth cohort. Methods We used multistage, stratified systematic sampling to recruit 24,200 mother-newborn pairs from the Taiwan national birth registration. Maternal psychologic problems and potential confounders were gathered by the standard questionnaire at 6 months old. At 3 years of age, information about the development of AD was assessed by International Study of Asthma and Allergies in Childhood via home interviews. Multiple logistic regression analysis was performed to estimate the association of postnatal maternal psychologic problems (postpartum depression (PPD) and maternal mental health index) and AD. Results The prevalence of physician-diagnosed AD was 10.5%. PPD increased the risk of subsequent physician-diagnosed AD in children after adjusting for potential confounders and other maternal mental health index ( aOR = 1.42, 95% CI = 1.21-1.66). We observed that the risk of AD associated with PPD was not confounded by other social demographic factors such as maternal AD, maternal education, family income, breastfeeding, day care, and number of siblings. Conclusions Postpartum depression increased the risk of childhood AD even when other maternal mental health index and social demographic factors are considered. Early intervention of PPD might be helpful for AD prevention. [ABSTRACT FROM AUTHOR]

Background Atopic dermatitis affects 15-30% of children worldwide. Onset of disease usually occurs within the first year of life, over half of which regress by 6 years of age. The aim of this study was to investigate the risk factors related to the persistence of infantile atopic dermatitis. Methods In this birth cohort study, patients were enrolled prenatally and followed until 6 years of age; 246 patients had infantile atopic dermatitis at 6 months of age. Family history, maternal and paternal total and specific Immunoglobulin E (IgE) levels, and cord blood IgE were recorded. Clinical examination, questionnaire survey, and blood samples for total and specific IgE of the children were collected at each follow-up visit. Results Of the 246 patients with infantile atopic dermatitis at 6 months of age, 48 patients had persisted atopic dermatitis at 6 years of age (19.5%). Risk factors associated with persistent infantile atopic dermatitis included egg white sensitization (odds ratio: 3.801, P = 0.020), and atopic dermatitis involving two or more areas at 6 months old (odds ratio: 2.921, P = 0.018) after multivariate analysis with logistic regression. Patients with persistent infantile atopic dermatitis had a higher risk of asthma before 6 years old (39.6% vs 24.2%, P = 0.032). Conclusion Egg white sensitization and the initial involvement of two or more areas at 6 months of age were associated with the persistent infantile atopic dermatitis. Patients with persistent infantile atopic dermatitis are more likely to develop asthma by 6 years of age. [ABSTRACT FROM AUTHOR]

To cite this article: Wen H-J, Wang Y-J, Lin Y-C, Chang C-C, Shieh C-C, Lung F-W, Guo YL. Prediction of atopic dermatitis in 2-yr-old children by cord blood IgE, genetic polymorphisms in cytokine genes, and maternal mentality during pregnancy. Pediatric Allergy Immunology 2011; 22: 695-703. Abstract Atopic dermatitis (AD) is the most common skin disease in childhood and the first step of atopic march. This study aimed to investigate whether AD in children could be better predicted by biologic markers (cord blood IgE [cbIgE], LT-α NcoI alleles, and FcεRI-β E237G genotypes) and maternal mentality during pregnancy, taking into account gender, socio-demographic factors, and parental atopy. From 2001 to 2005, 1264 mother-infant pairs were recruited to participate in a birth cohort study. Prenatal questionnaire was used to collect family history, maternal gestational conditions and mentality, and environmental exposures. Cord blood was collected and assayed for genotypes and IgE levels. Phone interviews at 6 months and 2 yrs of age were conducted to inquire children's health status, including AD occurrence. In addition to the known risk factors such as gender, maternal education, and parental atopy, biomarkers and maternal mentality during pregnancy were screened by logistic regression as candidate predictors of AD. Area-under-curve (AUC) statistic from receiver-operating characteristic (ROC) curve analysis was used to compare two predicting models with and without biomarkers and maternal mentality. A total of 730 pairs completed the prenatal questionnaire and phone interview and were included in final analysis. The prevalence of ever having physician-diagnosed AD by 2-yr-olds was 5.9%. Elevated cbIgE levels (≥0.5 kU/l), LT-α NcoI alleles, FcεRI-β E237G genotype, and maternal psychologic stress during pregnancy were significantly associated with AD. Comparison with AUCs of the classic model (including gender, maternal education, and parental atopy), the model adding cbIgE levels, genotypes in cytokine genes, and maternal stress (model 2) showed higher ability to discriminate between children with and without AD (AUC statistics: 0.63 [95% CI = 0.60-0.67] vs. 0.73 [95% CI = 0.70-0.76], respectively; model comparison, p = 0.027). We conclude that elevated cbIgE, LT-α and FcεRI-β genotypes, and maternal stress during pregnancy were associated with ever having physician-diagnosed AD in 2-yr-old children and increased the predictive ability for AD after taking into account gender, maternal education, and parental atopic history. [ABSTRACT FROM AUTHOR]

Background Recent studies indicate that prenatal vitamin D intake may protect against the development of atopic diseases in young children. Vitamin D has been shown to induce tolerogenic antigen-presenting cells such as dendritic cells. Whether the allergy-protective potential of prenatal vitamin D is mediated through such mechanisms is, however, unknown. Objective To evaluate the association between prenatal vitamin D supplementation and tolerogenic antigen-presenting cells in cord blood (CB) as determined by mRNA measurement of immunoglobulin-like transcripts (ILT)3 and ILT4. Methods A prospective multi-centre birth cohort was established in rural areas of five European countries. Information on maternal exposures including vitamin D intake was collected by questionnaires during pregnancy. The gene expression of ILT3 and ILT4 was analysed by real-time PCR in the CB of 927 children. Maternal vitamin D supplementation was assessed in Finland and France ( n=349). Results Maternal vitamin D supplementation during pregnancy was associated with an increase in the gene expression of ILT3 ( P=0.012) and ILT4 ( P<0.001). This association remained significant for ILT4 ( P=0.020) and showed a positive trend for the gene expression of ILT3 ( P=0.059) after multivariate analysis controlling for various confounders. Conclusions Vitamin D supplementation during pregnancy may increase the mRNA levels of ILT3 and ILT4 in CB. This finding may point towards an early induction of tolerogenic immune responses by maternal vitamin D intake. Cite this as: M. K. Rochat, M. J. Ege, D. Plabst, J. Steinle, S. Bitter, C. Braun-Fahrländer, J-C. Dalphin, J. Riedler, M. Roponen, M-R. Hirvonen, G. Büchele, H. Renz, R. Lauener, S. Krauss-Etschmann, E. von Mutius and the PASTURE Study group, Clinical & Experimental Allergy, 2010 (40) 786–794. [ABSTRACT FROM AUTHOR]

Eller E, Kjaer HF, Høst A, Andersen KE, Bindslev-Jensen C. Development of Atopic Dermatitis in the DARC birth cohort. Pediatr Allergy Immunol 2010: 21: 307–314. © 2009 John Wiley & Sons A/S The aim was to describe the relapsing pattern, sensitization and prognosis of atopic dermatitis (AD) in the first 6 yr in a population-based, prospective birth cohort. The DARC cohort includes 562 children with clinical examinations, specific-IgE and skin prick test at all follow-ups. All children were examined for the development of AD using Hanifin-Rajka criteria and for food hypersensitivity by oral challenges. Severity of AD was measured by objective SCORing Atopic Dermatitis (SCORAD). Point-prevalence of AD peaked at 18 months of age (10%) and decreased at 36 and 72 months to slightly below 7%. The 6-yr cumulative incidence was 22.8% and sensitization was found in 43% of children with AD. It was predominately sensitization to foods, however shifting toward inhalant allergens with age. Sensitization at ≥2 follow-ups affected severity, whereas short-term sensitization at one follow-up does not. Children with early, non-IgE mediated (intrinsic) AD outgrew more often their eczema; however if they develop persistent AD, they remain intrinsic. Early long-term sensitization worsens the prognosis, but 38% of all children have a debut later than 18 months of age. Boys had earlier onset of AD than girls. The large number of follow-ups gives a detailed picture of the relapsing pattern and shows that the relapses occur independently of time of onset. We could not establish any clear correlation between elimination diets and AD duration nor severity. [ABSTRACT FROM AUTHOR]

Prevention of allergic diseases depends on early identification of clinical markers preceding such disorders. This study describes the natural course of sensitization as measured by skin prick test (SPT) and specific immunoglobulin E (S-IgE) and analyses the association between early sensitization patterns and subsequent allergic disease at 6 yr of age. In an ongoing population-based birth cohort study of 562 children, follow-up visits were performed at 0, 3, 6, 9, 12, 18, 36, and 72 months. Visits included an interview, physical examination, SPTs, and S-IgE measurements for 12 food and inhalant allergens. The frequency of S-IgE sensitization to ≥1 inhalant allergen was constant from 0 to 6 months (9–10%), decreased at 12–18 months before increasing from 36 months onwards. S-IgE sensitization to at least one food allergen remained constant from 0 to 6 yr. SPT sensitization to food and inhalant allergens appeared from 3 and 12 months, respectively. Early food sensitization (S-IgE) between 3 and 18 months was found to be significantly (p < 0.05) associated with atopic dermatitis (OR: 4.0 [1.6–9.9]) and asthma (OR 4.0 [1.1–12.5]) at the age of 6 yr. Children with atopic dermatitis, asthma, or rhinoconjunctivitis, and sensitization at 6 yr, were sensitized to food allergens to a large extent (53%, 42%, and 47%, respectively) already at 6 months. Early inhalant sensitization (S-IgE) did not increase the risk of later allergic disease. Early atopic dermatitis (0–18 months) was also highly associated with subsequent allergic disease. Children with early food sensitization and/or atopic dermatitis would be a proper target group for future interventional studies. [ABSTRACT FROM AUTHOR]

Background: The prevalence of food hypersensitivity (FHS) and the relationship with atopic dermatitis (AD) is controversial. The aim of this study was to determine the development of FHS and to correlate this with AD in relation to sensitization and symptoms. Methods: This study combines new data from birth to 18 months of age with previous published results from 3 and 6 years. The Danish Allergy Research Centre cohort, including 562 children, is a unique, population-based, prospective birth cohort, with clinical examinations at all follow-ups. All children were examined for the development of AD using Hanifin-Rajka criteria and for FHS using interviews, skin prick test (SPT), specific immunoglobulin E (IgE), and food challenge according to EAACI guidelines. Results: Twenty children were confirmed with FHS to milk, egg, and peanut. FHS peaked at 18 months (3.6%) and then decreased to 1.2% at 72 months of age. No new cases were found after 3 years. Self-reporting could only be confirmed in 31% of cases. Among the 122 children with AD, 18 had FHS (14.8%). FHS was IgE-mediated in 95% of the cases but 16 of 20 children were additionally sensitized to other foods which they tolerated. Children with AD were neither more IgE-sensitized nor had higher levels of IgE when compared with healthy children but they were more persistently sensitized. Conclusions: Sensitization to foods in young children without food allergy seems to be a normal phenomenon. The discrepancy between sensitization, self-reported food-related symptoms and confirmed FHS illustrates the need to perform standardized oral challenges in order to confirm the diagnosis of FHS. [ABSTRACT FROM AUTHOR]

It has been proposed that exposure to infections and microbes protects against atopic diseases, but epidemiological data has so far been conflicting. We hypothesized that maternal exposure to infections and microbes before or during pregnancy would be of particular importance. To test this hypothesis, we studied the incidence of wheezing and atopic dermatitis (AD) in infants of mothers employed in child-care institutions – and thus presumably being highly exposed to infections and microbes – compared with infants of mothers not so employed. A total of 31471 mother-child pairs enroled in the Danish National Birth Cohort were followed prospectively. Information on wheezing episodes, AD, maternal employment, and other variables were collected by interview at 12 and 30 wk of gestation, and 6 and 18 months of age, and by linkage to the Danish Medical Birth Register and the Child-care Database. The relative risk was estimated in Cox proportional hazard models. Analyses were stratified by sibling status (first born or not), as older siblings are likely to be a significant source of infectious agents. The adjusted relative risks of wheeze, recurrent wheeze and AD was 1.14 (95% CI: 0.96–1.37), 1.37 (95% CI: 1.05–1.77), and 1.03 (95% CI: 0.81–1.31), respectively, for first-born infants of mothers employed in child-care institutions compared with infants of mothers not so employed. There was no effect of maternal employment in child-care institutions among infants with older siblings. In conclusion, the results did not support the hypothesis that maternal microbial exposure before or during pregnancy as reflected by maternal employment in child-care institutions protects the offspring against infant wheeze and AD. [ABSTRACT FROM AUTHOR]

This study determines the prevalence of atopic dermatitis, asthma, rhinoconjunctivitis, food hypersensitivity and urticaria and the frequency of sensitization in children with and without clinical allergic disease. In an ongoing prospective non-interventional birth cohort study of 562 unselected children, 404 children were subjected to interview, clinical examination, lung function measurements and allergy testing at 6 yr of age. Sensitization measured by skin prick test (SPT) and specific immunoglobulin E (S-IgE) was determined for 24 different allergens. The 1-yr period prevalence of atopic dermatitis, asthma and rhinoconjunctivitis was 14.4%, 6.2% and 13.6%. 25.7% of the children suffered from at least one of the three diseases. The frequency of sensitization in children with no disease (controls), any allergic disease, atopic dermatitis, asthma and rhinoconjunctivitis was 17%, 45%, 47%, 56% and 55% (defined as SPT ≥3 mm and/or S-IgE ≥0.35 kU/l for at least one allergen). Symptoms were linked to sensitization for 44% in the asthma group and 42% in the rhinoconjunctivitis group, whereas sensitization could not be linked to worsening of the eczema in any cases of atopic dermatitis. Overlap between the three diseases was significantly more frequent in sensitized children than in non-sensitized (19/46 = 41% vs. 9/58 = 16%, p = 0.004). The prevalence of food hypersensitivity and urticaria was 1.2% and 5.4% respectively. In unselected 6 yr old children, approximately half of the children with atopic dermatitis, asthma or rhinoconjunctivitis are IgE-sensitized. Sensitization tends to link these diseases to each other. [ABSTRACT FROM AUTHOR]

Exposure to high allergen levels in early life is a risk factor for the development of allergy. We previously reported limited effects of mite allergen impermeable mattress covers in the prevention and incidence of asthma and mite allergy (PIAMA) cohort at the age of 1 and 2 yr. We now present the results of follow-up at 4 yr objectives. To examine the effects of early reduction of house dust mite (HDM) allergen exposure by means of mattress covers on the incidence of allergy and asthma symptoms in the PIAMA birth cohort at the age of 4 yr. High-risk children (allergic mother) were prenatally recruited and randomly allocated to three groups; receiving mite allergen impermeable mattress covers (n = 416), placebo covers (n = 394) or no intervention (n = 472). At 4 yr of age, atopy was assessed by questionnaire; specific Immunoglobulin E (IgE) to inhalant and food allergens was measured in serum. Dust samples collected from the children's mattresses were analysed for mite allergens. Dermatophagoides farinae1 allergen (Der f 1) levels in dust were reduced in the active group. However, Dermatophagoides pteronissinus 1 (Der p 1) levels, sensitization and atopic symptoms were similar in all groups. We found no effect of mite allergen impermeable mattress covers on sensitization and atopy at 4 yr. Moreover, the allergen reducing effects of the covers had disappeared for one of the two mite allergens that were measured. [ABSTRACT FROM AUTHOR]

Sandin A, Björkstén B, Bråbäck L. Development of atopy and wheezing symptoms in relation to heredity and early pet keeping in a Swedish birth cohort. Pediatr Allergy Immunol 2004: 15: 316–322. © 2004 Blackwell Munksgaard The role of pet keeping during infancy for the development of allergy and asthma is still controversial. The objective of this population-based birth cohort study was to assess the development of atopy and different wheezing phenotypes during the first 4 yr of life in relation to heredity and early pet keeping. The cohort comprised all 1228 infants living in a Swedish county who were born over a 1-yr period. The parents replied to repeated questionnaires and 817 of the children were skin prick tested both at 1 and 4 yr. Cat keeping during the first year of life was associated with an increased risk of a positive skin prick test to cat at 1 yr of age [odds ratio (OR) 2.2, 95% confidence interval (CI) 0.9–5.6], but neither with sensitivity nor clinical symptoms of allergy at 4 yr. Dog keeping during the first year of life was associated with an increased risk of early-onset transient wheezing, but only in children with parental asthma (adjusted OR 4.3, 95% CI 1.5–12.1). In contrast, early dog keeping had an inverse association with sensitivity to pollen allergen at 4 yr (adjusted OR 0.3, 95% CI 0.1–0.9) and late-onset wheezing (adjusted OR 0.4, 95% CI 0.2–1.0). Thus, pet keeping during the first year of life was not associated with an increased risk of atopy at 4 yr, although a positive SPT to cat was more common at 1 yr. Our findings may even suggest that dog keeping during the first year of life might provide some protection from pollen allergy and late-onset wheezing and increase the risk of early-onset transient wheezing in children with heredity for asthma. [ABSTRACT FROM AUTHOR]

Several birth cohort studies have been initiated during the past two decades to study environmental and genetic risk factors for atopic dermatitis, asthma and allergic rhinitis. This article summarizes results from the German Multicentre Allergy Study (MAS), which has followed children (initially 1314) from birth (in 1990) to the present time. The effects of immunizations, allergen exposure, early sensitization patterns as well as upper airway infections on the subsequent development of asthma and atopy at school age are described. Furthermore, candidate gene studies of atopic dermatitis and increased total serum IgE levels on chromosomes 5q, 12q and 17q in MAS-children and their parents are outlined. [ABSTRACT FROM AUTHOR]