Family History Of Atopic Dermatitis Research Articles

Self-reported prevalence of latex allergy and associated factors in healthcare workers

In our country, the prevalence of latex allergy in health personnel has rarely been studied. To determine the prevalence and associated factors to self-reported latex allergy in health care workers. A cross-sectional study was conducted among 1,292 health care workers of a second level hospital. All workers were included and they were required to answer a structured questionnaire aimed at identifying latex allergy, atopic personal and family history, exposure to latex gloves and surgical background. Odds ratio (OR) and 95 % confidence interval (95 % CI) were estimated using regression logistic to investigate factors associated to latex allergy. The female to male ratio was 2.4:1. The men age 38.4 ± 11.6 years. The prevalence of latex allergy auto-reported was 9.7 %, with a confidence interval of 95 % (95 % CI) 8.1 %-11.3 %. There was no statistical difference by workplace (p = 0.508). Factors associated with latex allergy included female gender (OR = 1.68; 95 % CI: 1.03-2.73, p = 0.037), personal history of atopy (OR = 4.82; 95 % CI: 3.19-7.26, p < 0.0001), family history of atopic dermatitis (OR = 4.33, 95 % CI: 1.20-4.41) and history of allergy to fruits (OR = 4.33; 95 % CI: 2.62-7.14, p < 0.0001). Up to 10 out to 100 health workers may have latex allergy. The main factors associated with latex allergy in this study were: being a female, personal or familiar atopy and allergy to fruits.

Development of Respiratory Allergies, Asthma and Allergic Rhinits in Children with Atopic Dermatitis.

Children with atopic dermatitis (AD) usually develop symptoms when they reach the age of 6-7 years, but the risk of developing respiratory allergies, asthma and allergic rhinitis (AR) remains high. In most children with AD, the development of asthma and AR is associated with sensitization to food allergens and/or aeroallergens, while only a small percentage missed atopic diathesis. In about 35% of children with AD, food allergy is the provoking cause, and 60% of infants who had AD in the first 3 months of life were sensitized against aeroallergens by the age of 5. The aim of the study was to follow development of asthma and AR and to assess the most significant risk factors for developing respiratory allergy. A total of 114 children with AD were followed up for five years. At annual visits, the severity of disease, total immunoglobulin E (IgE) antibody values, skin prick tests, specific IgE antibodies to food allergens and aeroallergens, and absolute eosinophil count were assessed. Information on the family history of atopy and AD, feeding patterns during infancy, data on sensitivity to food allergens and/or aeroallergens, and on the occurrence of bronchial obstruction and nose symptoms were obtained. Asthma developed in 36 children, median age 7.7 years; 33 children had symptoms of AR, and 13 children with AD had both diseases associated; 38 children had sensitivity to food, of which 24 developed asthma and 13 AR; asthma developed in 18/23 children with sensitivity to aeroallergens, and almost an equal number of children developed AR. The increased absolute eosinophil count and specific IgE to aeroallergens and food allergens were the best asthma predictors, while AR predictors were family history and early onset of AD. In conclusion, children with AD are at a significant risk of developing respiratory allergies, and those with the increased absolute eosinophil count, positive specific IgE to aeroallergens and food allergens, heredity of AD, and early onset of AD are at the highest risk. Identification of risk factors will enable us to improve the treatments of AD in order to reduce the severity of disease and prevent manifestation of respiratory allergy.

THE CASE OF HERPETIC ECZEMA IN A CHILD WITH CONGENITAL ICHTHYOSIS AND ATOPIC DERMATITIS

The case of the development of herpetic eczema (Kaposi's eczema) is presented against the background of congenital ichthyosis and atopic dermatitis. It has been shown that the presence of atopic diseases such as allergic rhinitis and pollinosis, sensitization to many common allergens, and a positive family history of atopic dermatitis are factors of a more severe course of Kaposi's eczema. The presented clinical observation of the child with Kaposi's eczema showed that early diagnosis and timely initiated complex therapy are the determining factors of a favorable prognosis of the disease.

The severity of atopic dermatitis and the relation to the level of total IgE, onset of atopic dermatitis and family history about atopy

ABSTRACTThe aim of this study is the evaluation, if the level of total IgE, onset of atopic dermatitis (AD) and the family history are in the significant dependence to the severity of AD. The statistical evaluation of the dependence between the severity of AD and the the level of total IgE, family history and onset of AD was performed. 296 patients were examined. The level of total IgE above 200 IU/ml is recorded in 93 % of patients suffering from severe form and the positive data about atopy in family history are recorded in 66 % of patients with severe form of AD. The significant dependence was recorded between the severity of AD and parameters such as the level of total IgE, and family history about atopy. No dependence was recorded between the severity of AD and the onset of AD.

Do young adults with atopic dermatitis avoid harmful workplace exposure at their first job? A prospective cohort study.

Patients with atopic dermatitis (AD) are at high risk of chronic hand eczema. In this prospective cohort study, we assessed the influence of pre-hire-onset AD on the first job choice. We also analysed the potential association between AD and usage of preventive measures in high-risk occupations. Subjects (aged 19-24 years) who were followed from childhood until the second Study on Occupational Allergy Risks and indicated a job were included (n = 1566). We defined AD as doctor-diagnosed AD and symptoms of an itchy rash during the past 12 months before the study. Pre-hire-onset AD was having AD prior to the first job. Preventive measure usage was self-reported gloves use or use of ointment or moisturizer. We performed multiple imputations to deal with missing values and analysed associations using logistic regression models adjusted for several potential confounders. Risk categories of the first job did not differ between participants with pre-hire-onset AD and those without (odds ratio 1.05, 95 % confidence interval 0.59-1.87). AD status was not statistically significantly associated with usage of preventive measures (1.22, 0.56-2.64). Conversely, having received job counselling (2.76, 1.15-6.63) and a family history of AD (2.09, 1.01-4.31) were associated with a higher use of such measures. We could not confirm a healthy hire effect in this cohort of young adults. Although subjects with AD in high-risk occupations do not seem to use more preventive measures than their non-affected peers, job counselling seems to be an effective approach to encourage secondary prevention.

Association between Mouth Breathing and Atopic Dermatitis in Japanese Children 2-6 years Old: A Population-Based Cross-Sectional Study.

As mouth breathing is associated with asthma and otitis media, it may be associated with other diseases. Therefore, this population-based cross-sectional study evaluated the association of mouth breathing with the prevalences of various diseases in children. Preschool children older than 2 years were included. A questionnaire was given to parents/guardians at 13 nurseries in Tokushima City. There were 468 valid responses (45.2%). We defined a subject as a mouth breather in daytime (MBD) if they had 2 or more positive items among the 3 following items: “breathes with mouth ordinarily,” “mouth is open ordinarily,” and “mouth is open when chewing.” We defined subjects as mouth breathers during sleep (MBS) if they had 2 or more positive items among the following 3 items: “snoring,” “mouth is open during sleeping,” and “mouth is dry when your child gets up.” The prevalences of MBD and MBS were 35.5% and 45.9%, respectively. There were significant associations between MBD and atopic dermatitis (odds ratio [OR]: 2.4, 95% confidence interval [CI]: 1.4–4.2), MBS and atopic dermatitis (OR: 2.4, 95% CI: 1.3–4.2), and MBD and asthma (OR: 2.2, 95% CI: 1.2–4.0). After adjusting for history of asthma and allergic rhinitis; family history of atopic dermatitis, asthma, and allergic rhinitis; and nasal congestion; both MBD (OR: 2.6, 95% CI: 1.3–5.4) and MBS (OR: 4.1, 95% CI: 1.8–9.2) were significantly associated with atopic dermatitis. In preschool children older than 2 years, both MBD and MBS may be associated with the onset or development of atopic dermatitis.

Sensitization to aeroallergens in atopic dermatitis patients: association with concomitant allergic diseases.

A few reports demonstrate the relationship between IgE sensitization to aeroallergens in atopic dermatitis (AD) patients and other allergic diseases and parameters. The objective of this study was to evaluate, if there is a significant relationship between the sensitization to common aeroallergens in AD patients and the occurrence of asthma bronchiale, rhinitis and other atopic parameters. Sensitization to dust, mites, animal dander and bird feather was examined (skin prick test, specific IgE) and the relationship with the occurrence of asthma bronchiale, rhinitis, duration of AD, family history and onset of AD was evaluated. Two hundred and eighty-eight patients were examined - 90 men and 198 women. According to our results, IgE sensitization to animal dander, dust and mites may increase the risk of developing asthma or rhinitis. Persistent lesions of AD occur more often in patients with sensitization to animal dander, mites and dust. Patients with the sensitization to bird feather have the onset of AD more often above 5 years of age and in these patients, there is no relationship with the positive data about atopy in the family history. There is a greater likelihood of developing other allergic diseases in atopic dermatitis patients who suffer from sensitisation to animal dander, mites, and dust. Thus, prompt management of atopic dermatitis and allergy to inhallant allergens that develop in early infancy may be a successful method for preventing of atopic march.

Cohort study for prevention of atopic dermatitis using hair mineral contents

We undertook a cohort study to determine the association between hair mineral content and the onset of atopic dermatitis (AD) in infants. Eight hundred and thirty-four mother–infant pairs, who donated hair samples during one and ten-month health checkups, had their samples analyzed by proton induced X-ray emission (PIXE) for 32 mineral concentrations, and these mineral concentration data together with their AD family history were statistically examined for any relationships between them. Results indicated that of all minerals, only selenium (Se) and strontium (Sr) showed statistically significant associations for infants, while the same two elements were only marginally significant for mothers. Se deficiency in either infant or mother increased the AD risk. A Sr deficiency in infants increased AD risk, while the same deficiency in mothers decreased the risk. To predict the probability of AD development using this data, we performed logistic regression analysis, which provided a sensitivity of 65.9%, a specificity of 70.5%, a positive predictive value (PPV) of 10.3%, a negative predictive value (NPV) of 97.6% and a relative risk (RR) of 4.2, all far better than any corresponding figures explicitly mentioned in previously published papers.

SCORAD 75: a new metric for assessing treatment outcomes in atopic dermatitis

The scoring atopic dermatitis (SCORAD) is a well-established severity-scoring tool for atopic dermatitis (AD). Dead Sea climatotherapy (DSC) is a natural selective balneo-phototherapy utilized for many years to treat severe AD. The study's goal was to evaluate the impact of DSC on AD patients through assessment of SCORAD scores and to identify parameters associated with greater improvement. The files of 78 European patients (37 male patients and 41 female patients, mean age 37.8 years) with AD undergoing DSC were included in this retrospective study. Three sub-groups were delineated based on disease severity (as determined using the SCORAD). Demographic and clinical parameters as well as treatment characteristics--maximal and cumulative sun exposure doses--were recorded. SCORAD values were again recorded for assessment of treatment response. SCORAD 75 was defined as ≥75% decrease in SCORAD values following therapy. Statistical analysis including logistic regression models was used in multivariable analysis. After an average of 30 days of treatment, mean SCORAD values dropped from 50.5 to 11 (76.7%, P<0.001). 64.1% of all patients, regardless of sub-group, reached SCORAD 75, whereas 78.9% of patients with severe disease achieved this result. In a multivariate logistic regression, factors associated with achieving SCORAD 75 were maximal sun exposure, family history of AD and age at disease onset (P=0.002, P=0.009 and P=0.040 respectively). Dead Sea climatotherapy is a particularly effective treatment method for the sub-population of adults with severe AD. The SCORAD 75 can be useful for defining sub-populations in which treatment is more likely to be successful.

Prevalence of Food Allergy Among Preschool Children in Northern Thailand

Background: The epidemiology and clinical spectrum of food allergies (FA) confirmed by oral food challenge tests (OFC) in the Southeast Asian countries are limited. The aim of the present study was to examine the prevalence and characteristics of FA among preschool children in northern Thailand. Methods: Five hundred and forty-six children aged 3–7 years living in Chiang Mai, Thailand participated in this study. A cross-sectional parent questionnaire survey was conducted. Families with children reporting FA were invited to undergo further investigations with skin prick testing, serum specific IgE, and OFC. Results: A total of 452 out of 546 questionnaires (82.8%) were returned. Forty-two children (9.3%) were reported to have FA. The five leading allergic foods reported were shrimp, cow's milk, fish, chicken eggs, and ant eggs. The most commonly reported symptom was a skin rash (78.0%), followed by abdominal pain and vomiting (31.1%). Anaphylaxis was found in two children (3.4%), from ant eggs allergy. Eighteen children underwent OFC; five of them were positive to shrimp, fish, and crab. Either skin prick test or serum-specific IgE was positive in these children. Factors associated with parent-reported FA included personal and family history of atopic dermatitis. Conclusions: The prevalence of IgE-mediated FA confirmed on OFC was ≥1.11% (95% confidence interval: 0.41–2.98%). The most common causative food was shrimp. Ant eggs were a unique food allergen causing severe reactions in preschool children in northern Thailand.

Glutathione S-transferase M1 (GSTM1) polymorphism is associated with atopic dermatitis susceptibility in a Korean population

Atopic dermatitis (AD) is a chronic pruritic skin condition affecting as much as 15% of children in industrialized countries. While the underlying pathophysiology of AD is not entirely understood, several studies have suggested that AD may mediated by oxidative stress. Glutathione S-transferases (GSTs) are a class of polymorphic enzymes that function to protect against oxidative stress. To identify any possible associations between GSTs polymorphisms and AD susceptibility, the prevalence of two specific polymorphisms -GSTM1 and GSTT1 (homozygous deletion vs. undeleted) - were quantified by multiplex PCR in 145 patients with AD and 267 healthy controls. In individuals with AD, GSTM1/GSTT1 polymorphisms were compared with family history of AD, age of disease onset, disease severity [per SCORing Atopic Dermatitis (SCORAD)], serum IgE level and presence of other allergic diseases. While the GSTM1-null genotype was found to be significantly associated with AD (P = 0.033, OR = 1.579, 95% CI = 1.037-2.403), the correlation between the GSTT1-null genotype and AD did not reach statistical significance (P = 0.577, OR = 1.125, 95% CI = 0.744-1.702). The GSTM1-null genotype was also found to be significantly associated with a childhood onset of AD, the absence of other allergic diseases, and a family history of AD. In combination, these results suggest that GSTM1 is associated with AD susceptibility in Korean subjects.

Contact Dermatitis: From Basics to Allergodromes

CME Educational Objectives 1. Outline the clinical presentations and pathophysiology of both allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD). 2. Review the most common allergens and products responsible for allergic contact dermatitis in children. 3. Discuss the recommendations for management of children with suspected contact dermatitis including guidelines for referral for patch testing.

Risk Factors Associated With Persistent Airflow Limitation in Severe or Difficult-to-Treat Asthma: Insights From the TENOR Study

The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens study is among the largest to assess persistent airflow limitation and the first to evaluate a wide range of potential risk factors in high-risk patients with severe or difficult-to-treat asthma. A better understanding is needed regarding factors associated with persistent airway obstruction; this study was performed to determine demographic and clinical characteristics associated with persistent airflow limitation.Data from adult patients (>or= 18 years old) with severe or difficult-to-treat asthma were evaluated. Patients with COPD, obesity with a restrictive respiratory pattern, or a >or= 30 pack-year history of smoking were excluded. Patients with persistent airflow limitation (postbronchodilator FEV1/FVC ratio <or= 70% at two annual consecutive visits) and normal postbronchodilator FEV1/FVC ratio (75 to 85%) were compared. Multivariate analysis identified factors independently associated with persistent airflow limitation.Of 1,017 patients, 612 patients (60%) showed evidence of persistent airflow limitation. Risk factors were as follows: older age (odds ratio [OR] per 10 years, 1.4; 95% confidence interval [CI], 1.3 to 1.6); male gender (OR, 4.5; 95% CI, 2.3 to 8.5); black ethnicity (OR, 2.2; 95% CI, 1.3 to 3.8); current or past smoking (OR, 3.9; 95% CI, 1.8 to 8.6; and OR, 1.6; 95% CI, 1.2 to 2.3, respectively); aspirin sensitivity (OR, 1.5; 95% CI, 1.0 to 2.4); and longer asthma duration (OR per 10 years, 1.6; 95% CI, 1.4 to 1.8). Protective factors were Hispanic ethnicity, higher education, family history of atopic dermatitis, pet(s) in the home, and dust sensitivity.Persistent airflow limitation is prevalent in patients with severe or difficult-to-treat asthma and is associated with identifiable clinical and demographic characteristics.

The changing face of food hypersensitivity in an Asian community

Food allergy seems to be increasing in Asia as well as world-wide. Our aim was to characterize food protein sensitization patterns in a population of Asian children with possible food allergy. Children presenting to our allergy clinic over 3 years with symptomatic allergic disease and at least one specific food allergen sensitization documented on skin prick testing were included in the analysis. Two hundred and twenty-seven patients fulfilled inclusion criteria. Ninety (40%) of the positive skin tests were positive to egg, 87 (39%) to shellfish, 62 (27.3%) to peanut, 30 (13.2%) to fish, 27 (11.8%) to cow's milk, 21 (9.3%) to sesame, 13 (3.7%) to wheat and eight (3.2%) to soy. Peanut sensitization was the third most common sensitizing allergen, and seen mostly in young atopic children with multiple food hypersensitivities and a family history of atopic dermatitis. The median reported age of first exposure to fish and shellfish was 6 and 12 months, respectively. The mean age at presentation of children with shellfish hypersensitivity was at 6.7 years of age. The likelihood of shellfish sensitization was increased in children with concomitant sensitization to cockroaches. In contrast to previously reported low peanut allergy rates in Asia, in our review, peanut sensitization is present in 27% (62/227) of food-allergic children, mostly in patients with multiple food protein sensitizations. Temporal patterns of first exposure of infants to fish and shellfish are unique to the Asian diet. Shellfish are a major sensitizing food source in Asian children, especially in allergic rhinitis patients sensitized to cockroaches.

Hand Dermatitis Risk Factors Among Clinical Nurses in Japan

The purpose of this study was to establish hand dermatitis (HD) risk factors among Japanese nurses. A questionnaire was administered to 1,162 clinical nurses, from whom 860 replies were received (response rate of 74.0%). Their overall HD prevalence was 53.3%. Several risk factors were identified: using latex gloves (odds ratio [OR] 1.9), allergies in adulthood (OR 2.7), urticaria as an adult (OR 1.5), atopic dermatitis as an adult (OR 2.7), any allergies to latex products (OR 5.2), skin irritation following contact with latex (OR 4.1), contact dermatitis following contact with latex (OR 3.5), family history of hay fever (OR 1.6), and family history of atopic dermatitis (OR 1.9). The use of hand cream was associated with a 50% reduction in HD risk (OR 0.5). In this study, we found that Japanese clinical nurses suffer a significant occupational burden from HD. As such, it is essential that hospital managers consider interventions to reduce this troublesome occupational disease among clinical nurses in Japan, as elsewhere.

Diagnosis and treatment of atopic dermatitis in children and adults: European Academy of Allergology and Clinical Immunology/American Academy of Allergy, Asthma and Immunology/PRACTALL Consensus Report

There are remarkable differences in the diagnostic and therapeutic management of atopic dermatitis practiced by dermatologists and pediatricians in different countries. Therefore, the European Academy of Allergy and Clinical Immunology and the American Academy of Allergy, Asthma and Immunology nominated expert teams who were given the task of finding a consensus to serve as a guideline for clinical practice in Europe as well as in North America. The consensus report is part of the PRACTALL initiative, which is endorsed by both academies.

Atopic dermatitis and the 'hygiene hypothesis': too clean to be true?

The so-called 'hygiene hypothesis' postulates an inverse relationship between atopic dermatitis (AD) and an environment that leads to increased pathogen exposure. We sought to systematically identify, summarize and critically appraise: (i) the epidemiological evidence to suggest that environmental exposures that lead to an increase in microbial burden reduce the risk of AD; (ii) whether any specific infections have been shown to reduce AD risk; (iii) whether there is a link between immunizations, use of antibiotics and AD risk; and (iv) to comment on the new therapeutic approaches in AD that have evolved out of the 'hygiene hypothesis'. We searched Medline from 1966 until August 2004 to identify relevant studies for inclusion. Differences in study design and populations did not allow formal meta-analysis. Studies were therefore described qualitatively. We identified 64 studies that were relevant to our review, 27 (42%) of which were of prospective design. There was prospective evidence to support an inverse relationship between AD and endotoxins, early day care and animal exposure. Two well-designed cohort studies have found a positive association between infections in early life and AD, and measles vaccination and AD. Antibiotic use was consistently associated with an increase in AD risk even into the antenatal period, although a few studies did not reach conventional statistical significance. A few small randomized controlled trials have suggested that probiotics can reduce AD severity and that probiotics may also be able to prevent AD to some degree. Although population-based studies have suggested a consistent inverse relationship between AD and increasing family size, this does not seem to be explained by a straightforward increased exposure to a single environmental pathogen. The effect seen with early day care, endotoxin and animal exposure may be due to a nonpathogenic microbial stimulus of a chronic or recurrent nature. This would also explain the risk increase associated with antibiotic use. Caution should prevail in the prescribing of antibiotics early in life, especially in children with a family history of AD. Larger well-designed pragmatic trials on probiotics and the prevention and treatment of AD are now needed to inform whether such interventions should be used in routine clinical practice.

Correlation of Serum Total IgE, Eosinophil Granule Cationic Proteins, Sensitized Allergens and Family Aggregation in Atopic Dermatitis Patients with or without Rhinitis

Atopic dermatitis (AD) is a complex disease with both a genetic background and environmental interactions. Although multiple linkage-analyses about AD have been studied, there have been only a few family aggregation tests of AD or perennial allergic rhinitis (AR) to date. The association of allergen-specific IgE in AD and atopic dermatitis with allergic perennial rhinitis (ADR) have also been seldom discussed. The purpose of this study was to evaluate family aggregation and assess allergen-specific IgE in patients with AD and ADR. We also planned to investigate the effect of family history of AD on the prevalence of allergen-specific antibodies. The serum levels of IgE, eosinophil cationic protein (ECP) and major basic protein (MBP) were measured and compared in patients with AD and those with ADR. Proportional analysis compared allergen-specific IgE between AD and ADR. The family aggregation was conducted to estimate the odds ratio for various atopic diseases in different family members. Total IgE and allergen-specific antibodies in serum were compared between those patients who had AD with AR and those without. The result revealed that allergic rhinitis is the most common concomitant atopic disease associated with AD. The ADR group was more likely to have serum mite-, cockroach-, and feather-specific IgE. The positive rates for wheat, peanut and soybean were higher in those AD without rhinitis. In the family aggregation of AD, the odds ratio for siblings was higher than for parents, the ratios for brother and sister were 9.91 and 8.75, respectively. However, the odds ratio for parents of ADR was higher than siblings; the ratios for father and mother of ADR were 8.22 and 2.94, respectively. AD patients with family histories of AD were more likely to have mite-, soybean-, and peanut-specific antibodies in their serum. We concluded that aeroallergens are the most important allergens aggravating atopic diseases in Taiwan. Food plays an important role in the pathogenesis of AD. Measurement of serum total IgE combined with the MAST-CLA test could be helpful in the diagnosis of atopic diseases. The differential aggregation tendency for AD and ADR implicated the complexity of the gene-environment interaction in these atopic diseases.

Effect of breast-feeding on the development of atopic dermatitis during the first 3 years of life?results from the GINI-birth cohort study*1

Objective To investigate if exclusive breast-feeding for 4 months is associated with atopic dermatitis during the first 3 years of life. Study design Data on 3903 children were taken from yearly parental-administered questionnaires from a birth cohort study in Germany (recruited 1995-1998) comprised of a noninterventional (NI) and an interventional (I) subgroup. Outcomes were physician-diagnosed atopic dermatitis (AD) and itchy rash. Multiple logistic regression was performed for the entire cohort and stratified by family history of allergy and by study group adjusting for a fixed set of risk factors for allergies. Results Exclusive breast-feeding (52 % of children) was not associated with higher risk for AD either in the entire cohort (ORadj, 0.95; 95% CI, 0.79-1.14) or if stratified by family history of AD. In the I subgroup, but not in the NI subgroup, exclusive breast-feeding showed a significant protective effect on AD if compared with conventional cow's milk formula (ORadj, 0.64; 95% CI, 0.45-0.90). Conclusion These findings do not support the hypothesis that exclusive breast-feeding is a risk factor for development of atopic dermatitis but is protective if compared with conventional cow's milk. Observational studies might not be able to effectively control for selection bias and reverse causation.

Effect of breast-feeding on the development of atopic dermatitis during the first 3 years of life—results from the GINI-birth cohort study

Objective To investigate if exclusive breast-feeding for 4 months is associated with atopic dermatitis during the first 3 years of life. Study design Data on 3903 children were taken from yearly parental-administered questionnaires from a birth cohort study in Germany (recruited 1995-1998) comprised of a noninterventional (NI) and an interventional (I) subgroup. Outcomes were physician-diagnosed atopic dermatitis (AD) and itchy rash. Multiple logistic regression was performed for the entire cohort and stratified by family history of allergy and by study group adjusting for a fixed set of risk factors for allergies. Results Exclusive breast-feeding (52 % of children) was not associated with higher risk for AD either in the entire cohort (OR adj, 0.95; 95% CI, 0.79-1.14) or if stratified by family history of AD. In the I subgroup, but not in the NI subgroup, exclusive breast-feeding showed a significant protective effect on AD if compared with conventional cow's milk formula (OR adj, 0.64; 95% CI, 0.45-0.90). Conclusion These findings do not support the hypothesis that exclusive breast-feeding is a risk factor for development of atopic dermatitis but is protective if compared with conventional cow's milk. Observational studies might not be able to effectively control for selection bias and reverse causation.