Home About us Contact
|
Home About us Contact | ||
|
|
||
Atopic Sensitization (atopic + sensitization)
Selected AbstractsORIGINAL ARTICLE: Pre-Eclampsia, Placental Abruption and Increased Risk of Atopic Sensitization in Male Adolescent OffspringAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2009Leea Keski-Nisula Problem, The aim of this study was to investigate maternal pre-eclampsia (PE), placental abruption (PA) and atopy among offspring. Method of study, Obstetric data was recorded from 378 women who were included into the Caesarean delivery birth cohort during 1990,1992. When their children were 15,17 years old skin prick tests (SPTs) and inhalant allergen-specific (IAS) immunoglobulin E (IgE) were determined among offspring. Results, Adolescents whose mothers had either PE or PA at the time of delivery had more atopy and especially more severe atopy as measured by the incidence of SPTs positive for ,5 allergens (RR: 4.28, 95% CI: 1.54,11.92; P < 0.005) and elevated IAS IgE levels (,1.0 kU/L) (RR: 4.27, 95% CI: 1.08,16.99; P < 0.039). This increased risk was particularly observed in male adolescents. Conclusion, Maternal PE and PA were associated with an increased risk of severe atopy, especially in male adolescent offspring. [source] Anti-bacterial IgE in the antibody responses of house dust mite allergic children convalescent from asthma exacerbationCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2009B. J. Hales Summary Background Atopic sensitization to the house dust mite (HDM) is associated with altered antibody responses to the nasopharyngeal colonizing bacterium Haemophilus influenzae and children admitted to the emergency department for asthma exacerbation have reduced IgG responses to HDM allergens. Objective To investigate anti-bacterial and anti-allergen antibody responses during convalescence from asthma exacerbation and differences found in exacerbations associated with and without viral infection. Results IgE antibodies to the P6 bacterial antigen increased in 60% of sera during convalescence and for many children achieved titres as high as IgE titres to allergens. In contrast IgE anti-HDM titres declined during convalescence. The anti-bacterial IgE titres were the same in subjects with and without virus infection while the anti-HDM IgE declined more rapidly in virus-infected subjects. IgG titres to the major HDM allergens showed no consistent increase and the overall IgG anti-HDM titres even declined in subjects without a virus infection. Anti-bacterial IgG antibodies in contrast to IgE did not change. Patients with frequent episodic or persistent asthma had similar IgE anti-bacterial titres to patients with infrequent asthma during the acute phase, although they had reduced IgG titres to both the bacteria and the HDM. Conclusions During the period following an acute exacerbation of asthma there was a marked and specific increase in anti-bacterial IgE compared with a reduced IgE response to HDM. This provides further support for the concept of T-helper type 2 responses to bacterial antigens playing a role in asthma pathogenesis. [source] Rare TLR2 mutations reduce TLR2 receptor function and can increase atopy riskALLERGY, Issue 4 2009M. S. D. Kormann Background:, Common genetic variations in toll-like receptor 2 (TLR2), an innate pathogen recognition receptor, may influence the development of atopic diseases. So far, very little is known about the role of rare TLR2 mutations in these diseases. Objective:, We investigated the functional properties of six rare amino acid changes in TLR2 (and one amino acid change in a TLR2 pseudogene) and studied their effect on atopic sensitization and disease. Methods:, We identified rare TLR2 mutations leading to amino acid changes from databases. Functional effects of TLR2 variants were analyzed by NF-,B-dependent luciferase reporter assay and interleukin-8 enzyme linked immunosorbent assay in vitro. The frequency of these mutations was determined in a random sample of the general population (n = 368). Association with atopic diseases were studied in a cross sectional German study population (n = 3099). Results:, Three out of six mutations in the TLR2 gene altered receptor activity in vitro. Out of these, only the minor allele of R753Q occurred reasonably frequent in the German population (minor allele frequency 3%). The risk to develop atopy increased by 50% in carriers of the 753Q allele (P = 0.021) and total (P = 0.040) as well as allergen specific serum IgE levels (P = 0.011) were significantly elevated. Conclusion:, The rare but functionally relevant mutation R753Q in TLR2 may significantly affect common conditions such as atopic sensitization in the general population. [source] Specific IgE to allergens in cord blood is associated with maternal immunity to Toxoplasma gondii and rubella virusALLERGY, Issue 11 2008M. J. Ege Background:, Various studies have found reduced prevalences of atopic sensitization and atopic diseases in children previously exposed to infections or living conditions with a high microbial burden, such as the farming environment. Objective:, We sought to determine the relationships of cord blood immunoglobulin E (IgE) with maternal health conditions before and during pregnancy. Methods:, Pregnant women living in rural areas in five European countries were recruited in the third trimester of pregnancy. Information on maternal health during pregnancy was collected from maternity records and by questionnaires (n = 497). Specific IgE for inhalant and food allergens was assessed in cord blood and peripheral blood samples of the mothers. Results:, Inverse associations of cord blood IgE to seasonal allergens with positive maternal records for Toxoplasma gondii (adjusted odds ratio = 0.37 [0.17,0.81]) and rubella virus (adjusted odds ratio = 0.35 [0.13,0.96]) were found. The previously described effect of prenatal farm exposure on IgE to seasonal allergens was partly confounded by a positive maternal record for T. gondii. The number of maternal siblings, maternal contact to cats during pregnancy or during her first year of life, predicted a positive maternal record for T. gondii. Conclusions:, Maternal immunity to T. gondii and rubella may impact on atopic sensitization in the fetus. A positive T. gondii record explained the previously identified effect of prenatal farm exposure on IgE to seasonal allergens only to a minor extent. [source] The role of the intestinal microbiota in the development of atopic disordersALLERGY, Issue 11 2007J. Penders The prevalence of atopic diseases, including eczema, allergic rhinoconjunctivitis and asthma, has increased worldwide, predominantly in westernized countries. Recent epidemiological studies and experimental research suggest that microbial stimulation of the immune system influences the development of tolerance to innocuous allergens. The gastrointestinal microbiota composition may be of particular interest, as it provides an early and major source of immune stimulation and seems to be a prerequisite for the development of oral tolerance. In this review the observational studies of the association between the gut microbiota and atopic diseases are discussed. Although most studies indicated an association between the gut microbiota composition and atopic sensitization or symptoms, no specific harmful or protective microbes can be identified yet. Some important methodological issues that have to be considered are the microbiological methods used (traditional culture vs molecular techniques), the timing of examining the gut microbiota, the definition of atopic outcomes, confounding and reverse causation. In conclusion, the microbiota hypothesis in atopic diseases is promising and deserves further attention. To gain more insight into the role of the gut microbiota in the etiology of atopy, large-scale prospective birth cohort studies using molecular methods to study the gut microbiota are needed. [source] Timing of infection and development of wheeze, eczema, and atopic sensitization during the first 2 yr of life: The KOALA Birth Cohort StudyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 6 2010Monique Mommers Mommers M, Thijs C, Stelma F, Penders J, Reimerink J, van Ree R, Koopmans M. Timing of infection and development of wheeze, eczema, and atopic sensitization during the first 2 yr of life: The KOALA Birth Cohort Study. Pediatr Allergy Immunol 2010: 21: 983,989. © 2010 The John Wiley & Sons A/S To investigate if infections in pregnancy and very early in life present a risk for wheezing, eczema, or atopic sensitization in later infancy. A total of 2319 children enrolled before birth in the KOALA Birth Cohort Study were followed during their first 2 yr of life using repeated questionnaires. Information was obtained on common colds, fever, and diarrhea with fever as well as on wheeze and eczema at ages 3 and 7 months and 1 and 2 yr, respectively. Blood samples were collected from 786 children at age 2 yr for specific immunoglobulin E analyses. Children with a common cold [adjusted odds ratio (aOR) 2.03 95% CI 1.21,3.41] or fever episode (aOR 1.81 95% CI 1.10,2.96) in the first 3 months of life had a higher risk of new onset wheeze in the second year of life compared to children who had not. For children with diarrhea with fever in the first 3 months of life, the aOR for new onset wheeze in the second year of life was 3.94 (95% CI 1.36,11.40) compared to children without diarrhea. Infections becoming clinically manifest during the first 3 months of life may be a general marker for a wheezy phenotype. [source] Determinants of atopic sensitization in Turkish school children: Effects of pre- and post-natal events and maternal atopyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 1 2004Semanur Kuyucu Emergence of new environmental risk factors, and/or loss of protective factors of a traditional lifestyle may explain the increase, or variations in prevalence of allergic diseases. The aim of this study was to delineate the prevalence and spectrum of, and to reveal the causal and/or protective factors for atopic sensitization among a heterogenous cohort of Turkish children, for the first time in our country. The study design adhered to International Study of Asthma and Allergies in Childhood (ISAAC) phase II protocol. A self-administered parental questionnaire about demographic characteristics and detailed risk factors, and skin-prick test with 13 allergens were employed in a clustered random sample of 8,11-yr-old Turkish school children. Atopy was defined as the presence of at least one positive skin reaction to any allergen tested. The association between a total of 78 risk factors and different aspects of atopy were analyzed in 1144 children with multivariate logistic regression analysis. The overall prevalence of atopy was 20.6%. Most common sensitizations were to grass pollens, Dermatophagoides pteronyssinus and Blatella germanica. Day care attendance, high paternal education level, male gender and maternal asthma were significant risk factors for atopy. Breastfeeding more than 6 months (compared with 0,6 months), maternal smoking during pregnancy and a birth weight under 2500 g were inversely related to (or protective factors for) atopic sensitization. Maternal atopic disease had significant effects on risk factors pattern. In children with a maternal atopy history a low birth weight, day care attendance and maternal smoking during the first year of life independently increased the risk of atopic sensitization. Gender, breastfeeding and paternal education did not show any association with atopy in this group of children. A history of measles and low gestational age were significant protective factors for mite sensitization. This study showed that children of atopic mothers showed a different profile of risk factors associated with atopic sensitization, when compared with other children. Prenatal and early childhood events had important associations with atopic sensitization. [source] Atopy among schoolchildren in northern and southern Sweden in relation to pet ownership and early life eventsPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 1 2001L. Bråbäck Studies have suggested a higher prevalence of asthma and allergies in northern, as compared to southern, Scandinavia. The aim of this study was to evaluate regional differences in atopy in relation to pet ownership and certain early life events among schoolchildren (n = 2108) aged 10,11 years from Linköping in southern Sweden and Östersund in northern Sweden. The parents completed a questionnaire, comprising questions on home environment, heredity, socio-economic conditions, and the core questions on symptoms from the International Study of Asthma and Allergies in Childhood. The children were skin-prick tested to eight common inhalant allergens. Information on maternal smoking habits, gestational age, and anthropometric measures were obtained from the Swedish Medical Birth Registry. The prevalence of atopic symptoms and sensitization to pollen were similar in Östersund and in Linköping. A higher prevalence of sensitization to animal dander among children in Östersund could be linked to a higher occurrence of pets in the community. Current cat ownership was related to less sensitivity to cat allergen but only in children with an atopic heredity. Ponderal index > 30 kg/m3 was related to an increased risk of atopic sensitization, both in Linköping (adjusted odds ratio 2.1; 95% confidence interval 1.1,4.0) and in Östersund (adjusted odds ratio 2.0; 95% confidence interval 1.1,3.5). Maternal smoking during pregnancy was related to an increased risk of atopic sensitization among children in Linköping, whereas current smoking was associated with a decreased risk of sensitization in Östersund. In conclusion, we demonstrated that a high occurrence of pets in the community was associated with sensitization, whereas atopic symptoms were essentially unaffected. This study has also suggested an association between body size at birth and atopic sensitization at 10,11 years of age. [source] ORIGINAL ARTICLE: Chronic urticaria is associated with a differential helminth,arthropod-related atopy phenotypeTHE JOURNAL OF DERMATOLOGY, Issue 9 2010Alvaro DASCHNER Abstract The relationship between atopic sensitization and chronic urticaria is still controversial. In this study, we aimed to compare the prevalence of aeroallergen sensitization in chronic urticaria patients with (CU/As+) and without (CU/As,) sensitization against Anisakis simplex. Forty-nine CU/As+ and 80 CU/As, patients were studied and skin prick tests (SPT) were performed against aeroallergens. We assessed sensitization in a subgroup of patients with allergic rhinoconjunctivitis and/or bronchial asthma (RCBA) and compared the prevalence with a control group of 522 non-urticaria patients with RCBA. Forty-five percent of CU/As, and 60.4% of CU/As+ patients displayed positive SPT to at least one aeroallergen. CU/As+ patients had a higher prevalence of sensitization against pollen, mould or dander (PMD) (52.2% vs 29.1%, P < 0.01), whereas the prevalence of house dust mite (HDM) sensitization was not statistically different (26.3% in CU/As, and 36.7% in CU/As+). However, in chronic urticaria patients with RCBA, 53.8% of CU/As, and 57.9% of CU/As+ patients differed in the prevalence of HDM sensitization compared to the control group (33.5%, P = 0.03), whereas no difference could be stated for PMD sensitization. Compared to RCBA patients, both CU/As+ and CU/As, patients have a higher clinically relevant sensitization rate against HDM, thus displaying a differential atopy phenotype. [source] S39.1: Markers of fetal growth and prevalence of asthma, hay fever, atopic dermatitis and atopic sensitization in children at age 5-7 yearsBIOMETRICAL JOURNAL, Issue S1 2004Gabriele Bolte No abstract is available for this article. [source] Probiotics in pregnant women to prevent allergic disease: a randomized, double-blind trialBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2010C.K. Dotterud Summary Background, Previous reports have suggested that certain probiotics given to mothers and children at risk of atopy halves the incidence of atopic dermatitis (AD) at 2 years of age. Objectives, To examine if probiotics given to pregnant women in a nonselected population could prevent atopic sensitization or allergic diseases during the child's first 2 years. Methods, In a randomized, double-blind trial of children from a nonselected maternal population (ClinicalTrials.gov identifier: NCT00159523), women received probiotic milk or placebo from 36 weeks of gestation to 3 months postnatally during breastfeeding. The probiotic milk contained Lactobacillus rhamnosus GG, L. acidophilus La-5 and Bifidobacterium animalis subsp. lactis Bb-12. Children with an itchy rash for more than 4 weeks were assessed for AD. At 2 years of age, all children were assessed for atopic sensitization, AD, asthma and allergic rhinoconjunctivitis. The intention-to-treat (ITT) analysis was enabled by multiple imputations. Results, Four hundred and fifteen pregnant women were computer randomized. At 2 years, 138 and 140 children in the probiotic and the placebo groups, respectively, were assessed. In the ITT analysis, the odds ratio (OR) for the cumulative incidence of AD was 0·51 in the probiotic group compared with the placebo [95% confidence interval (CI) 0·30,0·87; P = 0·013]. There were no significant effects on asthma (OR 0·68, 95% CI 0·26,1·80; P = 0·437) or atopic sensitization (OR 1·52, 95% CI 0·74,3·14; P = 0·254). Conclusions, Probiotics given to nonselected mothers reduced the cumulative incidence of AD, but had no effect on atopic sensitization. [source] Pre- and post-natal exposure to antibiotics and the development of eczema, recurrent wheezing and atopic sensitization in children up to the age of 4 yearsCLINICAL & EXPERIMENTAL ALLERGY, Issue 9 2010S. Dom Summary Background Little data are available on the relationship between indirect antibiotic exposure of the child in utero or during lactation and allergic diseases. On the other hand, several studies have been conducted on the association with direct post-natal antibiotic exposure, but the results are conflicting. Objective The aim of this study was to investigate pre- and post-natal antibiotic exposure and the subsequent development of eczema, recurrent wheeze and atopic sensitization in children up to the age of 4 years. Methods We conducted an aetiologic study in 773 children based on a prospective birth cohort project in which environmental and health information were collected using questionnaires. Antibiotic exposure was assessed as maternal antibiotic intake during pregnancy and during lactation and as medication intake of the child. The chronology of exposures and outcomes was taken into account during the data processing. At the age of 1 and 4 years, a blood sample was taken for the quantification of specific IgE. Results Prenatal antibiotic exposure was significantly positively associated with eczema, whereas no association was found with recurrent wheeze and atopic sensitization. We found a positive, although statistically not significant, association between antibiotic exposure through breastfeeding and recurrent wheeze. Neither eczema nor atopic sensitization was significantly associated with antibiotic exposure through breastfeeding. Finally, we observed a negative association between the use of antibiotics in the first year of life and eczema and atopic sensitization, and also between antibiotic use after the first year of life and recurrent wheeze, eczema and atopic sensitization. Conclusion Indirect exposure to antibiotics (in utero and during lactation) increases the risk for allergic symptoms in children, while direct exposure to antibiotics appears to be protective. The biological mechanisms underlying these findings still need to be elucidated. Cite this as: S. Dom, J. H. J. Droste, M. A. Sariachvili, M. M. Hagendorens, E. Oostveen, C. H. Bridts, W. J. Stevens, M. H. Wieringa and J. J. Weyler, Clinical & Experimental Allergy, 2010 (40) 1378,1387. [source] The asthma,obesity link in childhood: open questions, complex evidence, a few answers onlyCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2007P. M. Matricardi Summary Obesity and asthma are public health priorities in developed countries. Genes which may contribute to the control of both conditions include those encoding for the ,2 -adrenergic receptor, tumour necrosis factor-, (TNF-,) and the insulin-like growth factor 1 (IGF-1). Prospective studies consistently supported a link between obesity and reported wheezing or asthma diagnosis in children. However, there are still no clear explanations for such a link. On one hand, overweight asthmatic children may perceive their asthma as worse. On the other hand, atopic sensitization and bronchial hyper-reactivity do not explain the observed associations. After puberty, the association between asthma and obesity tends to be stronger in girls than in boys. It is conceivable that severe obesity in adolescent females may aggravate asthma through mechanisms different from those linking prepubertal obesity to unremitting asthma in males. Future studies should therefore address multiple age- and gender-specific hypotheses about the mechanisms that link obesity to asthma throughout childhood. [source] Bronchial hyper-responsiveness to hypertonic saline and blood eosinophilic markers in 8,13-year-old schoolchildrenCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2004G. De Meer Summary Background In adult asthma, bronchial hyper-responsiveness (BHR) to indirect stimuli reflects eosinophilic activation more closely than BHR to stimuli that directly cause smooth muscle contraction. Aim To assess the relationship between BHR to the indirect stimulus hypertonic saline (HS), blood eosinophil numbers, and serum eosinophilic cationic protein (ECP) in children with and without current wheeze. Methods A cross-sectional survey among 8,13-year-old schoolchildren, using the International Study of Asthma and Allergic disease in Childhood questionnaire, bronchial challenge with HS, skin prick tests, serum IgE, blood eosinophil counts and ECP (in a subset). Based upon the presence of current wheeze (WHE) and BHR, we defined three case groups (WHE+BHR+, WHE,BHR+, WHE+BHR,) and the reference group (WHE,BHR,). By regression analyses, each case group was compared with the reference group for differences in atopic sensitization, blood eosinophil counts and serum ECP. Results Complete data were obtained for 470 children. BHR was present in 103 children (22%), 66 being asymptomatic and 37 symptomatic. Children of all three case groups were more often atopic. Sensitization to indoor allergens particularly occurred in children with BHR, irrespective of symptoms (P<0.05). Children with WHE+BHR+ had highest values for blood eosinophils and serum ECP (P<0.05). Children with WHE,BHR+ had less severe responsiveness. In atopic children with WHE,BHR+, serum ECP was higher than in children with WHE-BHR-(P<0.05). Conclusions BHR to HS is associated with blood markers of eosinophilic activation, particularly in atopic children. [source] Determinants of endotoxin levels in living environments of farmers' children and their peers from rural areasCLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2004M. Waser Summary Background Lower frequencies of asthma and hayfever have been observed in children with contact to livestock. At school age, the amount of endotoxin measured in the dust of children's mattresses is inversely related to the occurrence of atopic asthma, hayfever and atopic sensitization both in children from farming and non-farming households. Objective The aim of the present study was to investigate which home and lifestyle characteristics of farm and non-farm families contribute to endotoxin levels measured in different indoor home environments. Methods In the framework of the Allergy and Endotoxin (ALEX) Study, endotoxin was measured in dust samples from the living room floor and the child's mattress of 319 farmers' families and 493 non-farming families, and in settled dust from stables. Endotoxin content of all dust samples was determined by a kinetic Limulus assay (Limulus - Amebocyte -Lysate test). Information about the child's activities on farms, home characteristics and cleaning behaviours was obtained from parental questionnaires. Results Endotoxin levels in stables did not predict the amount of endotoxin measured in floors or mattresses. However, a dose-dependent association between the child's activity on the farm and indoor home endotoxin levels was observed, both in farm and non-farm children. In non-farm children pet keeping and the frequency of floor cleaning were additionally associated with endotoxin levels, whereas in farm children parental farm activities, study area, time since last cleaning, the mattress type as well as younger age of the children contributed to increased microbial exposure. Conclusion These results demonstrate that regular contact to farm animals increases indoor home endotoxin concentrations, both in farm and non-farm children, and might thus explain the protective effect of contact to livestock on atopic outcomes. To assess children's individual exposure to a microbial environment, measures of mattress dust exposure are needed as stable endotoxin concentrations were not associated with indoor home levels. [source] | ||||||||||||||||||||||