Development Of Atopy In Children Research Articles

The Primary Prevention of Atopy: Does Early Exposure to Cats and Dogs Prevent the Development of Allergy and Asthma in Children? A Comprehensive Analysis of the Literature.

The current literature shows mixed results relating to the significance of environmental exposure, such as owning a pet, and the development of atopy in children. Our review aimed to collect the most recent evidence on the association between early-life cat and dog ownership and the development of allergy and asthma. A comprehensive literature review was performed using PubMed and Scopus. The search included the main keywords of our PICO: (((early exposure) AND (children) AND (allergy)) OR (asthma)) AND (dog) OR (cat). Randomized controlled trials (RCTs), case-control studies, clinical trials, meta-analyses, and systematic reviews of children within the last five years (2018-2023) were searched and included. During the search process, 52 articles from PubMed and 43 from Scopus were found. A total of 17 articles were deemed to be suitable and included. Fairly consistent results regarding early exposure to pets, in particular dogs, and the prevention of food allergies have been described. Furthermore, there seems to be a protective effect against allergy and asthma in relation to the number of pets owned. The likelihood of a child developing allergy and asthma seems to be influenced by various factors, including the child's genetic background and early exposure to different environmental factors, including allergens that may interact with the gut microbiota and immune system.

G90 Ranitidine Treatment in Preterm Infants and The Prevalence of Atopy at Two Years of Age

BackgroundAcid suppression treatment has been linked to an increased incidence of allergy in adults. We evaluate how ranitidine, widely used off-label to treat gastro-esophageal reflux symptoms in neonates, may impair...

Controversial role of pets in the development of atopy in children

Exposure to environmental allergens originating from different sources has been implicated in the sensitization to the respective allergens and development of atopic diseases. Keeping domestic animals is associated with exposure to relevant allergens but there are controversial data whether this exposure promotes or protects from the development of atopy. We herein reviewed the literature regarding the available data for the exposure to pets (cats and/or dogs) and the development of atopy. For this purpose, we searched the PubMed database. This review attempts to answer the following questions that arise from the daily practice and the relevant studies, which are: a) is pet keeping associated with sensitization? b) is there an association between keeping pets and the development of asthma, allergic rhinitis and eczema, and, c) what is the underlying mechanism of any possible protective association? Despite the fact that several studies and meta-analyses have been conducted to explore the role of pets in the development of atopy, there are still conflicting pieces of evidence. It seems that there are different effects depending on the type of pets, the time and duration of exposure, and the genetic background of the individual. Further appropriately designed birth cohort studies are needed to explore whether exposure to relevant allergens from pets promotes or protects from the development of atopy.

Allergic diseases of the skin and drug allergies – 2016. Ranitidine treatment in preterm infants and the prevalence of atopy at two years of age

Methods We carried out a retrospective review of preterm infants of between 26 and 37 weeks gestation admitted over a two-year period between April 2008 and March 2010. Those preterm infants treated with the H2-receptor antagonist ranitidine for more than seven days were identified. A control group of preterm infants who did not receive treatment was selected by matching gestation, birth weight and disease severity using a validated scoring method. We analysed both maternal data (mode of delivery, use of intrapartum antibiotics, prolonged rupture of the membranes, sepsis) and neonatal data (birth weight, gestation, interventions, sepsis, type of feeding and neonatal complications). Information concerning the development of atopy in children in both groups, as well as any family history of atopy, was obtained through a simple questionnaire.

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

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

Fatty acids in cord blood plasma, the relation to soluble CD23 and subsequent atopy

Atopy is suggested to be linked to the balance between levels of n-6 and n-3 series of long chain polyunsaturated fatty acids (PUFAs) in the diet. In a nested case-control study, levels of fatty acids, IgE and soluble low affinity IgE receptor (sCD23) were measured in cord blood in 35 children who subsequently developed allergic sensitisation and atopic dermatitis before the age of 3, and similarly in 35 matched children without a history of atopy. We found a tendency to lower levels of the n-3 PUFAs eicosapentaenoic acid (EPA) and alpha-linolenic acid (ALA) in the cord blood plasma of atopics compared to non-atopics. Levels of sCD23 were negatively correlated to levels of n-3 series of PUFAs and n-9 eicosenoic acid, and levels of n-9 eicosenoic acid was negatively correlated to levels of IgE. There was no association between the levels of sCD23 and n-6 PUFAs. Lower levels of n-3 PUFAs in cord blood may be associated with the development of atopy in children. A possible mechanism may be through the regulation of CD23, thereby influencing IgE synthesis.

Asthma and pregnancy: interactions and management

<h3>Key points</h3> Asthma is one of the most common diseases complicating pregnancy. Pregnancy influences the control of asthma; its effect may be beneficial or detrimental. Asthma during pregnancy should be treated according to its severity in a step-wise manner and as aggressively as asthma in nonpregnant patients. It is safer for pregnant women with asthma to be treated with asthma medications than to have asthma symptoms and exacerbations. Uncontrolled and severe asthma is associated with adverse pregnancy outcomes for both mother and foetus. Frequent monitoring, severity-based pharmacotherapy, and prevention and prompt treatment of exacerbations are very important for the safe delivery of a healthy baby. Breastfeeding is strongly recommended for asthmatic females; it is associated with a reduction in the development of atopy in children, and the use of asthma medications is safe during breastfeeding. Integrated care (obstetrics and pulmonary), patient education, compliance with treatment and avoidance of triggering factors are key issues in the management of a pregnant asthmatic patient. <h3>Educational aims</h3> To describe interactions between asthma and pregnancy. To present management guidelines and discuss the use of specific asthma medications during pregnancy. <h3>Summary</h3> Asthma is one of the most common diseases complicating pregnancy. It can lead to significant morbidity for both mother and foetus. Pregnancy may also affect asthma control and severity. Therefore, pregnant asthmatic patients should receive integrated obstetric and respiratory care. The focus of asthma treatment remains the control of symptoms and maintenance of normal lung function of the mother. However, during pregnancy, the safe delivery of a healthy baby is an additional goal. It is safer for pregnant women with asthma to be treated with asthma medications than for them to have asthma symptoms and exacerbations. Asthma treatment during pregnancy follows the same step-wise approach as normal, and studies have shown that first-line asthma medications (such as inhaled glucocorticosteroids and ß₂-agonists) are not associated with an increased incidence of foetal abnormalities. Moreover, inhaled glucocorticosteroids have been shown to prevent exacerbations of asthma in pregnancy and should be used in persistent asthma to control the disease and prevent exacerbations. If acute exacerbations develop, they should be treated promptly and aggressively in order to avoid foetal hypoxia. Good pregnancy and asthma outcomes are achieved through integrated obstetric and respiratory care, close monitoring, meticulous tailoring of pharmacotherapy, patient education and reassurance. This review describes interactions between asthma and pregnancy and briefly presents treatment guidelines.

IgA Antibodies, TGF-β1 and -β2, and Soluble CD14 in the Colostrum and Development of Atopy by Age 4

Specific defense factors in breast milk together with length of breast-feeding and genetic predisposition may modulate the development of allergy. We studied whether IgA, soluble CD14 (sCD14), or transforming growth factor (TGF)-beta in colostrum could affect the development of atopy in children up to age 4. From a cohort of 4676, we selected four groups of children with either long or short exclusive breast-feeding (>3.5 or <0.5 mo); these groups further differed in the presence or absence of atopic heredity. In colostrum from mothers, we measured total IgA, IgA antibodies to cow's milk (CM) and casein, sCD14, and TGF-beta1 and -beta2. The children were divided into three groups: those with no atopic symptoms or IgE, those with allergic symptoms, and those with both outcomes. Mothers of infants later showing atopic symptoms or, in addition, having IgE sensitization (verified atopy) had a lower concentration of IgA casein antibodies in their colostrum than did mothers of infants with no indication of atopy at age 4. Low concentration of IgA casein antibodies was a significant risk for verified atopy. sCD14 levels were lower in colostrum of mothers with infants developing atopic symptoms and IgE sensitization than of those of infants with no atopy. Specific IgA antibodies to CM antigens and sCD14 in colostrum significantly associated with the appearance of both symptomatic and verified atopy by age 4.

Environment and development of atopy

Asthma and other atopic disorders are the result of complex interactions between genetic predisposition and multiple environmental influences. However, the marked increase in asthma prevalence over recent decades is unlikely to be due to genetic changes, highlighting the contribution of environmental factors to the process of allergic sensitization. This article reviews recent information on environmental influences on the development of atopy in children. Both observational and interventional studies continue to shed new light on the critical influence of early life events--such as events in pregnancy, exposure to allergens and endotoxin, pet ownership, infections, family size--and have highlighted important gene-environment interactions that modify the relationships between environmental exposures and atopic outcomes. The future is likely to see a concerted effort to further define the role that these environmental exposures play in allergic sensitization and the expression of atopic diseases, in order to provide a rational platform on which to develop new methods of allergy prevention that can be targeted at high-risk children.

Parental asthma as a risk factor for the development of early skin test sensitization in children

Background Recent epidemiologic evidence has challenged the paradigm suggesting a direct causal relationship between allergic sensitization and asthma. Objective We sought to investigate the role of a familial predisposition for asthma in the development of atopy in children. Methods Subjects were participants in the Tucson Children's Respiratory Study. Skin tests to aeroallergens were performed in parents and in children at ages 6, 11, and 16 years. Parents were considered asthmatic if they reported physician-confirmed asthma. Parents were divided into 4 phenotypes on the basis of skin sensitization (Skt+ or Skt−) and asthma status (As+ or As−): Skt−/As−, Skt−/As+, Skt+/As−, and Skt+/As+. Results Children's allergic sensitization differed among parental phenotypes at all ages ( P < .0001). Children in the Skt+/As− and Skt+/As+ groups were significantly more likely to be allergic than children in the Skt−/As− group at all ages. Among children with allergic parents, those with at least one parent with asthma were significantly more likely to have positive skin test responses than those with nonasthmatic parents at age 6 years (52.4% vs 37.4%, P < .005) and 11 years (70.1% vs 55.6%, P < .005) but not at age 16 years (82.3% vs 75.1%, P = .180). Results were independent of wheezing in the child and of the characteristics of atopy in parents. The Skt−/As+ group had too few subjects for meaningful comparisons. Conclusion Among children of atopic parents, parental asthma is a risk factor for allergic sensitization in early childhood. The strong association between allergic sensitization and asthma is at least in part explained by an increased susceptibility to allergen sensitization in subjects predisposed to asthma.

Absence of association between delayed type hypersensitivity to tuberculin and atopy in children in The Gambia.

An inverse association between delayed type hypersensitivity to tuberculin and atopy has been observed in children, suggesting that exposure to mycobacteria may influence the immune response to allergens. To investigate the relationship between tuberculin responses and atopy in children living in three different environments in The Gambia. In this cross-sectional study a total of 507 school-aged children were recruited from rural, urban poor or urban affluent communities. They were assessed for skin responses to five common allergens and tuberculin, presence of bacille Calmette-Guérin (BCG) scar, presence of intestinal parasites, and total serum IgE. Atopy was defined as the presence of a skin prick test response > or = 3 x 3 mm to at least one allergen. The overall prevalence of atopy was 33% but there was a significant variation among the three study groups. The prevalence of atopy was 22% in urban poor, 36% in urban affluent, and 43% in rural children. Controlling for potential confounding factors, children in the rural community had a significantly higher odds ratio, 3.3 (95% confidence interval 1.8-6.0) of being atopic than children from the urban poor community. No association between atopy and tuberculin response or BCG scar was observed in any of the three groups. Serum IgE levels were higher among children of the urban poor group but were not associated with tuberculin response or BCG scar in any of the groups. Environmental factors have an important influence on the development of atopy in children in The Gambia but delayed type hypersensitivity to tuberculin is not a protective factor.

Fever episodes in early life and the development of atopy in children with asthma.

The hygiene hypothesis proposes that declining exposure to infections may contribute to the allergy and asthma "epidemic", but studies to identify the infections involved have so far provided conflicting data. An alternative approach could be based on an attempt to identify the mechanisms common to several different infections, which may exert an atopy "protective" effect. One of these mechanisms may be fever, which is frequently associated with infections and may stimulate the synthesis of interferon-gamma. The aim of this study was to test whether the frequency of fever episodes in the first years of life are related to the development of atopy. Asthmatic (cases, n=317) and nonasthmatic children (controls, n=304) attending the outpatients' allergy clinic were enrolled. The number of fever episodes in the first 2 yrs of life was retrospectively assessed by parental report via a questionnaire completed by interview. Atopy was determined by skin-prick tests to 10 prevalent inhalant allergens at the time of examination. Fever episodes in the first or in the second year of life were significantly more frequent among children with asthma. However, this difference was totally accounted for by a subgroup of children who started wheezing in the first 12 months of life. A significant inverse association between fever episodes in the first 12 months of life and atopy was found among cases, but not in controls. The association persisted after adjusting for age, sex, daycare attendance and family history of atopic disease and this was totally accounted for by asthmatic children who started wheezing after the first 12 months of life. No significant association was found between fever episodes in the second year of life and atopy for cases and controls. The data presented here suggests that fever episodes early in life may affect the natural history of asthma by preventing the development of atopy and highlights the need to monitor fever episodes of any kind in longitudinal studies aimed at investigating the hygiene hypothesis prospectively.

Human milk polyunsaturated long-chain fatty acids and secretory immunoglobulin A antibodies and early childhood allergy.

The possible protective effect of breast milk against atopic manifestations in infancy, i.e. atopic eczema and food allergy, has been controversial for the last decades. Besides the methodological problems, differences in the composition of human milk could explain these controversies. The aim of this study was to investigate the composition of polyunsaturated fatty acids (PUFA) and secretory immunoglobulin A (S-IgA) levels to food proteins (ovalbumin and beta-lactoglobulin) and an inhalant allergen (cat) in milk from mothers of allergic and non-allergic children. Blood samples were obtained at birth and at 3 months from 120 children. Skin prick tests were performed at 6, 12 and 18 months, and the development of atopic diseases was assessed in the children. Breast milk samples were collected from their mothers at birth and monthly during the lactation period. Milk PUFA composition was measured by gas chromatography, and enzyme-linked immunosorbent assay (ELISA) was used to measure total S-IgA, anti-cat S-IgA, anti-ovalbumin S-IgA, and anti-beta-lactoglobulin S-IgA. Allergic disease developed in 44/120 children (22/63 children of allergic mothers and 22/57 children of non-allergic mothers). Lower levels of eicosapentaenoic acid, C20:5 n-3 (EPA), docosapentaenoic acid C22:5 n-3 (DPA), and docosatetraenoic acid C22:4 n-6 (DHA) (p < 0.05 for all) were found in mature milk from mothers of allergic as compared to milk from mothers of non-allergic children. The total n-6:total n-3 and the arachidonic acid, C20:4 n-6 (AA):EPA ratios were significantly lower in transitional and mature milk from mothers of allergic children, as compared to milk from mothers of non-allergic children. The PUFA levels in serum of allergic and non-allergic children were largely similar, except for higher levels of C22:4 n-6 and C22:5 n-6 (p < 0.05 for both) and a higher AA:EPA ratio in serum phospholipids in the former group (p < 0.05). Changes in the levels of milk PUFA were reflected in changes in PUFA serum phospholipids, particularly for the n-6 PUFA. The AA: EPA ratio in maternal milk was related, however, to the AA:EPA only in serum from non-allergic children, while this was not the case in allergic children. The levels of total S-IgA, anti-cat S-IgA, anti-ovalbumin S-IgA, and anti-beta-lactoglobulin S-IgA in milk from mothers of allergic, as compared to non-allergic, children were similar through the first 3 months of lactation. Low levels of n-3 PUFA in human milk, and particularly a high AA:EPA ratio in maternal milk and serum phospholipids in the infants, were related to the development of symptoms of allergic disease at 18 months of age. The milk PUFA composition influenced the composition of PUFA in serum phospholipids of the children. We also showed that the lower levels of colostral anti-ovalbumin S-IgA and lower total S-IgA in mature milk from atopic mothers did not influence the development of allergic disease in the children up to 18 months of age. The findings indicate that low alpha-linolenic acid, C18:3 n-3 (LNA) and n-3 long-chain polyunsaturated fatty acids (LCP) 20-22 carbon chains, but not the levels of S-IgA antibodies to allergens, are related to the development of atopy in children.

Measles and atopy in Guinea-Bissau

Summary Background Epidemiological studies have led to speculation that infections in early childhood may prevent allergic sensitisation but evidence to support this hypothesis is lacking. We investigated whether measles infection protects against the development of atopy in children of Guinea-Bissau, West Africa. Methods We conducted a historical cohort study in Bandim, a semi-rural district of Bissau, the capital of Guinea-Bissau. 395 young adults, first surveyed in 1978-80 aged 0-6 years, were followed up in 1994. Our analyses were restricted to 262 individuals still living in Bandim for whom a measles history, documented in childhood, was judged to be reliable. We defined atopy as skin-prick test positivity (≥3 mm weal) to one or more of seven allergens. Findings 17 (12·8%) of 133 participants who had had measles infection were atopic compared with 33 (25·6%) of 129 of those who had been vaccinated and not had measles (odds ratio, adjusted for potential confounding variables 0·36 [95% Cl 0·17-0·78], p=0·01). Participants who had been breastfed for more than a year were less likely to have a positive skin test to housedust mite. After adjustment for breastfeeding and other variables, measles infection was associated with a large reduction in the risk of skin-prick test positivity to housedust mite (odds ratio for Dermatophagoides pteronyssinus 0·20 [0·05-0·81], p=0·02; D farinae 0·20 [0·06-0·71], p=0·01). Interpretation Measles infection may prevent the development of atopy in African children.

Recommendations for Soy Infant Formula: A Review of the Literature and a Survey of Pediatric Allergists

Statements in the pediatric and gastroenterology literature to the effect that use of soybean formula should be avoided because of its high "allergenicity" seem to be unfounded. A review of the literature as well as personal experience in practice and with two dietary prophylactic studies spanning 15 years suggest that the availability of soybean formula constitutes a useful contribution to our knowledge of the handling of many nutritional problems of infants and children. The availability of soybean formula provides parents of infants with cow's milk allergy a nutritional food that can be used in the preparation of many kinds of food dishes and desserts to provide variety for children on restrictive diets. Over the past four decades, the use of soybean formula as a part of a dietary prophylaxis against the development of atopy in children of allergic families has been well accepted by the vast majority of infants who have received it. A survey of pediatric allergists showed the limits of what can be obtained by even the least demanding questionnaire. Given the rarity of reactions and the difficulty in identifying a clear causal agent, the average allergist is "overasked" by even a simple one-page set of questions. If anything, the wide range of answers indicates widespread confusion. A definitive answer about the existence of soybean allergies cannot be obtained without a detailed protocol for reporting and cross-validating such observations in a collaborative study. The use of soybean in infant feeding goes back many centuries in Chinese and Japanese cultures. In modern Japan, soy formula is commonly used either as a substitute for human breast milk or as a postweaning protein source in the first year of life. The first reported use of a soybean preparation for feeding infants with milk allergy was reported by Hill and Stuart in 1929.(1) Yet recommendations for soybean formula have remained controversial. We review the evidence for and against soybean formula and present data from a survey of pediatric allergists.