The Atopic March: Progression from Atopic Dermatitis to Allergic Rhinitis and Asthma

Ratio of Klebsiella/Bifidobacterium in early life correlates with later development of paediatric allergy

Several studies have reported that intestinal microbial colonisation patterns differ between non-allergic and allergic infants. However, the microbial signature underlying the pathogenesis of allergies remains unclear. We aim to gain insight into the development of the intestinal microbiota of healthy infants and infants who develop allergy in early life, and identify potential microbiota biomarkers of later allergic disease. Using a case-control design in a Chinese sub-cohort of a Singaporean birth cohort (GUSTO), we utilised 16S rRNA gene sequencing to assess intestinal microbial composition and diversity of 21 allergic and 18 healthy infants at 3 weeks, 3 months and 6 months of age, and correlated the microbiota with allergy at ages 18 and 36 months. Pronounced differences in intestinal microbiota composition between allergic and healthy infants were observed at 3 months of age. The intestine of healthy infants was colonised with higher abundance of commensal Bifidobacterium. Conversely, Klebsiella, an opportunistic pathogen, was significantly enriched in the allergic infants. Interestingly, infants with a high Klebsiella/Bifidobacterium (K/B) ratio (above the population median K/B ratio) at age 3 months had an odds ratio of developing allergy by 3 years of age of 9.00 (95% confidence interval 1.46-55.50) compared to those with low K/B ratio. This study demonstrated a relationship between the ratio of genera Klebsiella and Bifidobacterium during early infancy and development of paediatric allergy in childhood. Our study postulates that an elevated K/B ratio in early infancy could be a potential indicator of an increased risk of allergy development. This line of research might enable future intervention strategies in early life to prevent or treat allergy. Our study provides new insights into microbial signatures associated with childhood allergy, in particular, suggests that an elevated K/B ratio could be a potential early-life microbiota biomarker of allergic disease.

Atopic Dermatitis: Early Treatment in Children

Therapeutic regimens for the treatment and long-term management of AD traditionally had a two-fold objective of decreasing skin inflammation and repairing the defective skin barrier. Essential treatments for AD in children should include topical moisturizers for skin hydration and prevention of flares, topical anti-inflammatory medications (e.g. corticosteroids, calcineurin inhibitors, PDE4 inhibitor), allergen/irritant avoidance, and treatment of skin infections. Treatment regimens should be severity-based, and implemented in a stepwise approach tailored to the individual patient. This stepwise approach includes initial use of emollients, gentle skin care, and escalating to more potent anti-inflammatory treatments as the disease severity increases. Currently available systemic medications should be reserved for the presence of recalcitrance to topical therapies due to associated toxicities. We believe that early treatment of AD is not only essential in treating the skin disease, but also in preventing the development of additional atopic diseases, such as food allergy, asthma and allergic rhinitis. The defective skin barrier of AD permits a route of entry for food and environmental allergens, and upon exposure, keratinocytes secrete TSLP, which activates the T_H2 pathway. This T_H2 differentiation sets off the atopic march and the subsequent diseases that are seen. This review highlights treatment options and strategies in pediatric AD therapy with an emphasis on early therapy. Supporting evidence on the efficacy and safety of each intervention will be discussed.

The Long-Term Course of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic, relapsing condition, meaning that the intensity of symptoms usually fluctuates over time. Changes in skin physiology may be evident from birth, suggesting that AD may be a lifelong condition marked by intermittent symptoms/disease activity. Methodological considerations for studying the long-term course of AD are reviewed in detail. Improved measurement of the frequency and duration of active disease periods can help to elucidate more about the clinical course AD and the role of treatment in long-term outcomes.

Exercise-Induced Bronchospasm and Allergy

Sport is an essential part of childhood, with precious and acknowledged positive health effects but the impact of exercise-induced bronchoconstriction (EIB) significantly reduces participation in physical activity. It is important to recognize EIB, differentiating EIB with or without asthma if the transient narrowing of the airways after exercise is associated with asthmatic symptoms or not, in the way to select the most appropriate treatment among the many treatment options available today. Therapy is prescribed based on symptoms severity but diagnosis of EIB is established by changes in lung function provoked by exercise evaluating by direct and indirect tests. Sometimes, in younger children it is difficult to obtain the registration of difference between the preexercise forced expiratory volume in the first second (FEV1) value and the lowest FEV1 value recorded within 30 min after exercise, defined as the gold standard, but interrupter resistance, in association with spirometry, has been showed to be a valid alternative in preschool age. Atopy is the main risk factor, as demonstrated by epidemiologic data showing that among the estimated pediatric population with EIB up to 40% of them have allergic rhinitis and 30% of these patients may develop adult asthma, according with atopic march. Adopting the right treatment and prevention, selecting sports with no marked hyperventilation and excessive cooling of the airways, children with EIB can be able to take part in physical activity like all others.

Life-course of atopy and allergy-related disease events in tropical sub-Saharan Africa: A birth cohort study

BACKGROUND

In high-income countries, allergy-related diseases (ARDs) follow a typical sequence, the 'Atopic March'. Little is known about the life-course of ARDs in the markedly different, low-income, tropical environment. We describe ARDs in a tropical, African birth cohort.

METHODS

Ugandan children were followed from birth to 9 years. ISAAC questionnaires were completed at intervals; doctor-diagnosed ARDs were recorded throughout follow-up. Skin prick tests (SPTs) were performed at 3 and 9 years. Atopy was defined as ≥1 positive SPT.

RESULTS

Of the 2345 live-born children, 1214 (52%) were seen at 9 years. Wheeze and eczema were common in infancy, but by 9 years, only 4% reported recent wheeze, 5% eczema and 5% rhinitis. Between 3 and 9 years, atopy prevalence increased from 19% to 25%. Atopy at 3 or 9 years was associated with reported ARD events at 9 years, for example OR = 5.2 (95% CI 2.9-10.7) for atopy and recent wheeze at 9 years. Reported or doctor-diagnosed ARD events in early childhood were associated with the same events in later childhood, for example OR = 4.4 (2.3-8.4) for the association between reported wheeze before 3 years with reported recent wheeze at 9 years, but progression from early eczema to later rhinitis or asthma was not observed.

CONCLUSION

Allergen sensitization started early in childhood and increased with age. Eczema and wheeze were common in infancy and declined with age. Atopy was strongly associated with ARD among the few affected children. The typical Atopic March did not occur. Environmental exposures during childhood may dissociate atopy and ARD.

The global state of psoriasis disease epidemiology: a workshop report

The International Psoriasis Council, a global nonprofit organization dedicated to innovation across the full spectrum of psoriasis, led a symposium to discuss the current state of psoriasis epidemiology and to introduce the vision and development of a Global Psoriasis Atlas. The symposium was held on 9 September 2015 at the 45th annual meeting of the European Society for Dermatological Research, Rotterdam, the Netherlands. Collectively, these presentations highlighted challenges associated with assessing psoriasis epidemiology and emphasized the urgent need for an authoritative resource to clarify psoriasis disease burden on a global scale.

Mesenchymal Stem Cell Therapy for Inflammatory Skin Diseases: Clinical Potential and Mode of Action

Inflammatory skin disorders that cause serious deterioration of the quality of life have become one of the major public concerns. Despite their significance, there is no fundamental cure to date. Mesenchymal stem cells (MSCs) possess unique immunomodulatory properties which make them a promising tool for the treatment of various inflammatory diseases. Our recent preclinical and clinical studies have shown that MSCs can be successfully used for the treatment of atopic dermatitis (AD), one of the major inflammatory skin diseases. This observation along with similar reports from other groups revealed the efficacy and underlying mechanisms of MSCs in inflammatory dermatosis. In addition, it has been proposed that cell priming or gene transduction can be novel strategies for the development of next-generation high-efficacy MSCs for treating inflammatory skin diseases. We discuss here existing evidence that demonstrates the regulatory properties of MSCs on immune responses under inflammatory conditions.

Atopy and autoimmune thyroid diseases: melatonin can be useful?

Recently, there has been growing interest in the relationship between allergic and autoimmune diseases. Allergy and autoimmunity can be considered two potential outcomes of dysregulated immunity and analysis of literature data shows a strong positive association between a history of Th2-mediated allergic disorders and Th1-mediated autoimmune disorders.Autoimmune thyroid diseases are the most common of all autoimmune pathological conditions.Currently, the mechanisms explaining an association among atopy, autoimmunity, and thyroid diseases are not fully understood.There are data in literature pointing to the relationship between melatonin and thyroid activity. Several studies have suggested a paracrine role for this molecule in the regulation of thyroid activity, documenting that administration, as an antioxidant, in thyroid tissues under conditions of increased oxidative stress, could be helpful to reduce the oxidative processes involved in autoimmune thyroid diseases.Although thyroid autoimmunity has been regularly associated with atopic conditions in children, the possible protective role of melatonin has not yet been investigated.This review summarizes what is known regarding the connection between atopy and autoimmune thyroid diseases, and analyses the probable beneficial action of melatonin.

Douchi (fermented Glycine max Merr.) alleviates atopic dermatitis-like skin lesions in NC/Nga mice by regulation of PKC and IL-4

BACKGROUND

Douchi (fermented Glycine max Merr.) is produced from fermented soybeans, which is widely used in traditional herbal medicine. In this study, we investigated whether Douchi attenuates protein kinase C (PKC) and interleukin (IL)-4 response and cutaneous inflammation in Atopic dermatitis (AD)-like NC/Nga mice.

METHODS

To induce AD-like skin lesions, D. farinae antigen was applied to the dorsal skin of 3-week-old NC/Nga mice. After inducing AD, Douchi extract was administered 20 mg/kg daily for 3 weeks to the Douchi-treated mice group. We identified the changes of skin barrier and Th2 differentiation through PKC and IL-4 by immunohistochemistry.

RESULTS

Douchi treatment of NC/Nga mice significantly reduced clinical scores (p < 0.01) and histological features. The levels of PKC and IL-4 were significantly reduced in the Douchi-treated group (p < 0.01). The reduction of IL-4 and PKC led to decrease of inflammatory factors such as substance P, inducible nitric oxide synthase (iNOS) and Matrix metallopeptidase 9 (MMP-9) (all p < 0.01). Douchi also down-regulated Th1 markers (IL-12, TNF-α) as well as Th2 markers (IL-4, p-IκB) (p < 0.01).

CONCLUSION

Douchi alleviates AD-like skin lesions through suppressing of PKC and IL-4. These results also lead to diminish levels of substance P, iNOS and MMP-9 in skin lesions. Therefore, Douchi may have potential applications for the prevention and treatment of AD.

Prevalence and risk factors for asthma among children aged 0-14 years in Hangzhou: a cross-sectional survey

Background

Asthma is a global problem. Prevalence varies among different countries and cities. We aimed to obtain the prevalence, describe the characteristics, and discover factors that may relate to asthma in Hangzhou.

Methods

This cross-sectional study was conducted in Hangzhou. The subjects were children aged 14 years and younger. A control group of non-asthma children that matched in age and sex with each asthmatic patient was also randomly selected and interviewed. International Study of Asthma and Allergies in Childhood and National Epidemiology study of Asthma and Allergies in China questionnaires were used in this survey.

Results

We have questionnaired 13,877 children, and 665 (4.8 %) children were diagnosed asthma. The guardians regarded the cost of asthma management affordable in 49.4 %, tolerable in 46.9 %, and intolerable in 3.7 %. Both guardians and children have been absent from work or school due to children’s asthma.

Respiratory tract infection was the most common trigger of asthma attacks (85.1 %). Other common causes included cold air, house dust, exercise, fish and shrimp, pollen, and et al. Interestingly, we also found in children 6 years and older, some triggers happened more than that in children 5 years and younger. Those factors included exercise, emotional changes, house dust, pollen, renovation works in the home, mosquito–repellent incense and pets (all the p values were <0.05).

We compared some factors may relate to asthma development. Higher percentage of family history of asthma, personal history of allergy (atopic dermatitis, drug allergy and food allergy), comorbidities (allergic rhinitis, sinusitis, adenoidal hypertrophy, and urticaria), caesarean birth and complications ever happened during pregnancy were discovered in asthma children than in non-asthma children (all the p values were <0.05). Exclusive breastfeeding within first 6 months and keeping animals had higher percentage in non-asthma children than in asthma (both the p values were <0.05).

Inhaled corticosteroid (ICS)/ICS + long-acting beta2 agonists (LABA) was applied to 46.2 % of patients. Traditional Chinese medicine (TCM) was used in 44.2 % of asthma children, while leukotriene receptor antagonist (LTRA) was used in 36.4 % of them. The adherence scored higher in TCM than in ICS/ICS + LABA (P = 0.003) and LTRA.

Conclusions

In conclusion, we conducted an epidemiology study in Hangzhou. The prevalence of childhood asthma was 4.8 %. Asthma was an economic and social burden to both children and guardians. Risk factors of asthma development may include caesarean birth, personal history of allergy and concomitant allergic diseases. Exclusive breastfeeding within first 6 months and keeping animals might be protecting factors. TCM was really popular in China besides ICS/ICS + LABA and LTRA.

Short-term Effects of Ambient Air Pollution on Emergency Department Visits for Asthma: An Assessment of Effect Modification by Prior Allergic Disease History

Objectives

The goal of this study was to investigate the short-term effect of ambient air pollution on emergency department (ED) visits in Seoul for asthma according to patients’ prior history of allergic diseases.

Methods

Data on ED visits from 2005 to 2009 were obtained from the Health Insurance Review and Assessment Service. To evaluate the risk of ED visits for asthma related to ambient air pollutants (carbon monoxide [CO], nitrogen dioxide [NO₂], ozone [O₃], sulfur dioxide [SO₂], and particulate matter with an aerodynamic diameter <10 μm [PM₁₀]), a generalized additive model with a Poisson distribution was used; a single-lag model and a cumulative-effect model (average concentration over the previous 1-7 days) were also explored. The percent increase and 95% confidence interval (CI) were calculated for each interquartile range (IQR) increment in the concentration of each air pollutant. Subgroup analyses were done by age, gender, the presence of allergic disease, and season.

Results

A total of 33 751 asthma attack cases were observed during the study period. The strongest association was a 9.6% increase (95% CI, 6.9% to 12.3%) in the risk of ED visits for asthma per IQR increase in O₃ concentration. IQR changes in NO₂ and PM₁₀ concentrations were also significantly associated with ED visits in the cumulative lag 7 model. Among patients with a prior history of allergic rhinitis or atopic dermatitis, the risk of ED visits for asthma per IQR increase in PM₁₀ concentration was higher (3.9%; 95% CI, 1.2% to 6.7%) than in patients with no such history.

Conclusions

Ambient air pollutants were positively associated with ED visits for asthma, especially among subjects with a prior history of allergic rhinitis or atopic dermatitis.

Longitudinal association between early atopic dermatitis and subsequent attention-deficit or autistic disorder: A population-based case-control study

Atopic dermatitis (AD) is one of the common allergic diseases in children. The presence of allergic diseases was found to have association with the risk of developing attention-deficit hyperactivity disorder (ADHD) or autistic spectrum disorder (ASD) in children, but it is still inconclusive. This study was to investigate the longitudinal relationship between AD developed during toddlerhood and subsequent development of ADHD or ASD in later childhood. Toddlers born between 1998 and 2008 and diagnosed with AD at the age younger than 3 years and older than 1 month were retrieved from Taiwan's National Health Insurance Research Database. Age- and gender-matched toddlers with no lifetime AD were enrolled as the control group. All enrolled toddlers were followed until 2011 to identify the development of ADHD or ASD. Multivariate Cox regression analysis was performed to analyze the hazard ratios (HRs). The risks associated with allergic comorbidities were analyzed. A total of 18,473 toddlers were enrolled into the AD group. The presence of AD significantly increased the risk of developing ADHD (HR = 2.92, 95% confidence interval [CI] = 2.48-3.45) or ASD (HR = 8.90, 95% CI = 4.98-15.92) when aged 3 years or older. Children from the AD group with 3 comorbidities together, namely, allergic rhinitis, allergic conjunctivitis, and asthma, had the greatest risk of developing ADHD and ASD (ADHD: HR = 4.67, 95% CI = 3.81-5.43; ASD: HR = 16.65, 95% CI = 8.63-30.60). In conclusion, toddlers who suffer from AD at the age younger than 3 years are at a higher risk of developing ADHD and ASD during later childhood. Pediatricians taking care of toddlers with AD should have knowledge of this increased risk of developing ADHD and ASD later in life, especially when children have certain comorbidities such as allergic rhinitis, allergic conjunctivitis, and asthma.

Longitudinal association between early atopic dermatitis and subsequent attention-deficit or autistic disorder: A population-based case-control study

Atopic dermatitis (AD) is one of the common allergic diseases in children. The presence of allergic diseases was found to have association with the risk of developing attention-deficit hyperactivity disorder (ADHD) or autistic spectrum disorder (ASD) in children, but it is still inconclusive. This study was to investigate the longitudinal relationship between AD developed during toddlerhood and subsequent development of ADHD or ASD in later childhood. Toddlers born between 1998 and 2008 and diagnosed with AD at the age younger than 3 years and older than 1 month were retrieved from Taiwan's National Health Insurance Research Database. Age- and gender-matched toddlers with no lifetime AD were enrolled as the control group. All enrolled toddlers were followed until 2011 to identify the development of ADHD or ASD. Multivariate Cox regression analysis was performed to analyze the hazard ratios (HRs). The risks associated with allergic comorbidities were analyzed. A total of 18,473 toddlers were enrolled into the AD group. The presence of AD significantly increased the risk of developing ADHD (HR = 2.92, 95% confidence interval [CI] = 2.48-3.45) or ASD (HR = 8.90, 95% CI = 4.98-15.92) when aged 3 years or older. Children from the AD group with 3 comorbidities together, namely, allergic rhinitis, allergic conjunctivitis, and asthma, had the greatest risk of developing ADHD and ASD (ADHD: HR = 4.67, 95% CI = 3.81-5.43; ASD: HR = 16.65, 95% CI = 8.63-30.60). In conclusion, toddlers who suffer from AD at the age younger than 3 years are at a higher risk of developing ADHD and ASD during later childhood. Pediatricians taking care of toddlers with AD should have knowledge of this increased risk of developing ADHD and ASD later in life, especially when children have certain comorbidities such as allergic rhinitis, allergic conjunctivitis, and asthma.

Different risk factor patterns for adult asthma, rhinitis and eczema: results from West Sweden Asthma Study

BACKGROUND

Atopic diseases including asthma, rhinitis and eczema have increased in the second half of the past century. This has been well studied among children and adolescents but with the exception of asthma to a much lesser extent in adults. The adult risk factor pattern of atopic diseases, in particular of eczema, and their relation to allergic sensitization are yet to be fully elucidated. Studies among adults that have compared the risk factor pattern for these conditions in the same material are very few. The objective of this study was to compare the risk factor patterns for asthma, rhinitis and eczema in a randomly selected adult population.

METHODS

A questionnaire survey on atopic diseases was dispatched by mail to 30,000 randomly selected individuals in West Sweden aged 16-75 years and 62 % participated. A subgroup of 2000 individuals was selected for clinical examinations including blood sampling for specific serum Immunoglobulin E to common airborne allergens and 1172 attended.

RESULTS

The prevalence of current asthma was 11.8 %, current rhinitis 42.8 %, current eczema 13.5 and 2.3 % had all three conditions while 13.9 % had at least two conditions. No mutual risk factor was identified for all three conditions. Allergic sensitization was a strong risk factor for current asthma (OR 4.1 CI 2.7-6.3) and current rhinitis (OR 5.1 CI 3.8-6.9) but not so for current eczema. Obesity was a risk factor for current asthma and current rhinitis, while farm childhood decreased the risk for current asthma and current rhinitis. Occupational exposure to gas dust or fumes and female sex was associated with an increased risk of current asthma and current eczema.

CONCLUSIONS

There are different risk factor patterns for asthma, rhinitis and eczema in adults but some risk factors are overlapping between some of the conditions. The effect of mutable risk factors should be assessed further in longitudinal studies.

Molecular Mechanisms of Cutaneous Inflammatory Disorder: Atopic Dermatitis

Atopic dermatitis (AD) is a multifactorial inflammatory skin disease resulting from interactions between genetic susceptibility and environmental factors. The pathogenesis of AD is poorly understood, and the treatment of recalcitrant AD is still challenging. There is accumulating evidence for new gene polymorphisms related to the epidermal barrier function and innate and adaptive immunity in patients with AD. Newly-found T cells and dendritic cell subsets, cytokines, chemokines and signaling pathways have extended our understanding of the molecular pathomechanism underlying AD. Genetic changes caused by environmental factors have been shown to contribute to the pathogenesis of AD. We herein present a review of the genetics, epigenetics, barrier dysfunction and immunological abnormalities in AD with a focus on updated molecular biology.

Transplantation of human skin microbiota in models of atopic dermatitis

Atopic dermatitis (AD) is characterized by reduced barrier function, reduced innate immune activation, and susceptibility to Staphylococcus aureus. Host susceptibility factors are suggested by monogenic disorders associated with AD-like phenotypes and can be medically modulated. S. aureus contributes to AD pathogenesis and can be mitigated by antibiotics and bleach baths. Recent work has revealed that the skin microbiome differs significantly between healthy controls and patients with AD, including decreased Gram-negative bacteria in AD. However, little is known about the potential therapeutic benefit of microbiome modulation. To evaluate whether parameters of AD pathogenesis are altered after exposure to different culturable Gram-negative bacteria (CGN) collected from human skin, CGN were collected from healthy controls and patients with AD. Then, effects on cellular and culture-based models of immune, epithelial, and bacterial function were evaluated. Representative strains were evaluated in the MC903 mouse model of AD. We found that CGN taken from healthy volunteers but not from patients with AD were associated with enhanced barrier function, innate immunity activation, and control of S. aureus. Treatment with CGN from healthy controls improved outcomes in a mouse model of AD. These findings suggest that a live-biotherapeutic approach may hold promise for treatment of patients with AD.

Study of the Atopic March: Development of Atopic Comorbidities

BACKGROUND

Atopic dermatitis (AD) is often the first step in the atopic march leading to the development of asthma or allergic rhinitis. The goal of this study was to determine whether early intervention with pimecrolimus limits the atopic march in infants with AD and to evaluate its efficacy and safety.

METHODS

This was a 3-year double-blind study in which patients were randomized to pimecrolimus or vehicle and then open-label pimecrolimus for a planned further 3 years. Rescue topical corticosteroid was permitted if 3 days of study medication led to no improvement; investigators made decisions on rescue medication until week 14 and caregivers thereafter. Efficacy assessments included disease-free days, Eczema Area and Severity Index, and body surface area affected.

RESULTS

Infants ages 3 to 18 months with recent-onset AD (≤3 months) were observed for a mean of 2.8 years (N = 1,091). No significant differences between pimecrolimus- and placebo-treated groups were found in the percentage of patients with AD who developed asthma (10.7%) or other allergic conditions (allergic rhinitis, 22.4%; food allergy, 15.9%; allergic conjunctivitis, 14.1%; one or more atopic comorbidities, 37.0%) by study end. Allergic rhinitis, food allergy, and having one or more atopic comorbidities (but not asthma or allergic conjunctivitis alone) developed significantly more often in infants with greater AD severity at baseline. Pimecrolimus was significantly more effective than vehicle for AD treatment at week 14. Adverse event incidences were similar.

CONCLUSIONS

This longitudinal observation of infants with AD provides evidence of the atopic march. Pimecrolimus was safe and effective in infants with mild to moderate AD.

Associations of TNFα -308G>A, TNFα -238G>A, IL-1α -889C>T and IL-10 -1082G>A Genetic Polymorphisms with Atopic Diseases: Asthma, Rhinitis and Dermatitis

BACKGROUND

Polymorphisms of cytokine genes are an interesting focus for association studies involving atopic diseases due to their role in immune cell communications during inflammation. The aim of this study was to investigate associations of TNFα -308G>A, TNFα -238G>A, IL-1α -889C>T and IL-10 -1082G>A polymorphisms with atopic diseases with adjustment for confounding lifestyle and environmental factors.

METHODS

This study was performed on 356 Croatian students. The diagnosis of atopic asthma, atopic rhinitis and atopic dermatitis was based on symptoms reported by the modified International Study of Asthma and Allergies in Childhood questionnaire and a positive skin prick test (SPT) to at least one common inhalatory allergen. Genetic polymorphisms were genotyped using the polymerase chain reaction-based technique. The influence of personal (gender, body mass index, parental history of atopic disease), lifestyle (cigarette smoking, pet ownership) and environmental (urban/rural residency, residency in continental/Mediterranean region) factors reported in the questionnaire was investigated by univariate and multivariate analysis.

RESULTS

Compared to the control subjects, univariate analysis showed a significant negative association of the TNFα -308G>A polymorphism with atopic asthma, atopic dermatitis, asthma and skin symptoms and positive SPT. These observations were confirmed in a multivariate model only for atopic dermatitis and skin symptoms (atopic dermatitis: OR = 0.27; 95% CI 0.07-1.00; p = 0.050; skin symptoms: OR = 0.29; 95% CI 0.10-0.83; p = 0.021).

CONCLUSIONS

The results indicate a protective role of TNFα -308G>A genetic polymorphisms regarding atopic dermatitis and skin symptoms even after controlling for personal, lifestyle and environmental factors. Further studies are needed to elucidate the molecular patterns of this association in atopic dermatitis and other chronic inflammatory skin disorders.

Transgenic rat model of childhood-onset dermatitis by overexpressing telomerase reverse transcriptase (TERT)

Childhood-onset dermatitis is one of the most common skin disorders in children. Although various mouse models that mirror aspects of dermatitis have become available, there is still a need for an animal model that develops dermatitis in childhood and is more suitable for performing tissue transplantation experiments. There is emerging evidence that peripheral blood T lymphocytes from patients with dermatitis have significantly increased telomerase activity. Here, we developed telomerase reverse transcriptase (TERT)-expressing transgenic (Tg) rats that spontaneously developed eczematous skin inflammation in childhood. Newborn TERT-Tg rats developed visible dermatitis in 56 % of cases, and the skin lesions microscopically showed spongiosis and acanthosis with infiltration of lymphocytes, eosinophils and mast cells. TERT-Tg rats with dermatitis exhibited increased CD4 (2.5-fold) and CD8 (fivefold) T cell numbers compared with dermatitis-free TERT-Tg rats. Stronger TERT activity was observed in the peripheral lymphocytes of dermatitis-positive TERT-Tg rats than those of dermatitis-free TERT-Tg rats. RT-PCR analysis revealed that IL-4 was markedly elevated in the spleen of dermatitis-positive TERT-Tg rats, and that interferon-gamma was increased in the dermatitis lesions. Moreover, skin grafting of TERT-Tg rats with dermatitis onto T cell-deficient nude rats demonstrated that the inflamed skin lesions could not be maintained. Taken together, the results suggest that TERT activation in T lymphocytes is one of the potential predisposing factors for dermatitis. Moreover, our results demonstrated that the TERT-Tg rats mirror aspects of human childhood-onset dermatitis and that these animals represent a potential animal model system for studying childhood-onset dermatitis.

Utilization of Preventive Health Care in Adults and Children With Eczema

INTRODUCTION

Chronic disease is a barrier to delivery of preventive health care and health maintenance. However, health behaviors of adults and children with eczema, a chronic skin disorder, have not been examined. This study examined associations of eczema with vaccination, disease screening, health maintenance, and healthcare utilization.

METHODS

This study investigated 34,613 adults and 13,298 children from the 2012 National Health Interview Survey, a prospective questionnaire-based study. Data were analyzed between August 2014 and January 2015.

RESULTS

Adult eczema was associated with higher odds of vaccination for tetanus (OR [95% CI]=1.37 [1.22, 1.54]); influenza (1.23 [1.10, 1.37]); hepatitis A (1.21 [1.04, 1.41]) and B (1.21 [1.07, 1.35]); human papilloma virus (1.66 [1.32, 2.08]); and pneumonia (1.35 [1.19, 1.54]), but not herpes zoster virus (1.07 [0.87, 1.31]). Adult eczema was associated with increased measurement of blood glucose (1.29 [1.16, 1.44]); cholesterol (1.19 [1.06, 1.34]); blood pressure (1.84 [1.56, 2.08]); and HIV infection (1.50 [1.34, 1.70]), but not Pap smears (1.11 [0.95, 1.30]); colon cancer screening (p=0.17); or mammograms (p=0.63). Adults with eczema were more likely to interact with general doctors, mid-level providers, mental health professionals, eye doctors, podiatrists, chiropractors, therapists, obstetrician/gynecologists, and other specialists (p≤0.01). Childhood eczema was associated with higher rates of vaccination for influenza (p<0.0002); well child checkups (p=0.002); and interaction with most types of healthcare providers (p≤0.01). Many associations remained significant in multivariate models controlling for sociodemographics and healthcare interaction frequency.

CONCLUSIONS

Eczema in adults and children is associated with greater utilization of preventive health care and health maintenance, but not cancer screening.

Multiple Transcriptome Data Analysis Reveals Biologically Relevant Atopic Dermatitis Signature Genes and Pathways

Several studies have identified genes that are differentially expressed in atopic dermatitis (AD) compared to normal skin. However, there is also considerable variation in the list of differentially expressed genes (DEGs) reported by different groups and the exact cause of AD is still not fully understood. Using a rank-based approach, we analyzed gene expression data from five different microarray studies, comprising a total of 127 samples and more than 250,000 transcripts. A total of 89 AD gene expression signatures '89ADGES', including FLG gene, were identified to show dysregulation consistently across these studies. Using a Support Vector Machine, we showed that the '89ADGES' discriminates AD from normal skin with 98% predictive accuracy. Functional annotation of these genes implicated their roles in immune responses (e.g., betadefensin, microseminoprotein), keratinocyte differentiation/epidermal development (e.g., FLG, CORIN, AQP, LOR, KRT16), inflammation (e.g., IL37, IL27RA, CCL18) and lipid metabolism (e.g., AKR1B10, FAD7, FAR2). Subsequently, we validated a subset of signature genes using quantitative PCR in a mouse model. Using a bioinformatic approach, we identified keratinocyte pathway over-represented (P = <0.0006) among the 89 signature genes. Keratinocytes are known to play a major role in barrier function due to their location in the epidermis. Our result suggests that besides immune- mediated pathway, skin barrier pathways such as the keratinocyte differentiation pathway play a key role in AD pathogenesis. A better understanding of the role of keratinocytes in AD will be important for developing novel "barrier therapy" for this disease.

A Herbal Formula, Atofreellage, Ameliorates Atopic Dermatitis-Like Skin Lesions in an NC/Nga Mouse Model

We evaluated the anti-atopic dermatitis (AD) effect of Atofreellage (AF), a herbal formula composed of 10 medicinal plants. AD was induced on the dorsal skin areas of NC/Nga mice (male, seven weeks old) by daily application of 2,4-dinitrochlorobenzene (DNCB) for five weeks. After three weeks of DNCB application, 200 μL of AF (0, 25, 50 or 100 mg/mL) was applied to the skin lesions. Histological findings, blood cell populations, serum levels of immunoglobulin E (IgE), histamine, pro-inflammatory cytokines, and inflammatory signaling in the skin tissue, and T-helper cell type 2 (Th₂)-related cytokines in splenocytes were analyzed. Histopathological findings showed AF treatment notably attenuated the thickness of dorsal skin, and eosinophil infiltration. AF treatment (especially 100 mg/mL) also demonstrably ameliorated the blood cell population abnormalities, as the notable elevation of serum concentrations of IgE, histamine, TNF-α, IL-6 and IL-1β were remarkably normalized by AF treatment. Western blot analysis evidenced the apparent normalization of inflammatory signals (ERK, p38 MAP kinase, JNK, and NF-κB) in the skin tissue. Additionally, AF treatment notably attenuated the activation of Th₂-dominant cytokines (IL-13, IL-4, and IL-5) in Con A-treated splenocytes in an ex vivo assay. In conclusion, this study provides experimental evidence for the clinical relevance of Atofreellage.

Estrogen Signaling Modulates Allergic Inflammation and Contributes to Sex Differences in Asthma

Asthma is a chronic airway inflammatory disease that affects ~300 million people worldwide. It is characterized by airway constriction that leads to wheezing, coughing, and shortness of breath. The most common treatments are corticosteroids and β2-adrenergic receptor antagonists, which target inflammation and airway smooth muscle constriction, respectively. The incidence and severity of asthma is greater in women than in men, and women are more prone to develop corticosteroid-resistant or “hard-to-treat” asthma. Puberty, menstruation, pregnancy, menopause, and oral contraceptives are known to contribute to disease outcome in women, suggesting a role for estrogen and other hormones impacting allergic inflammation. Currently, the mechanisms underlying these sex differences are poorly understood, although the effect of sex hormones, such as estrogen, on allergic inflammation is gaining interest. Asthma presents as a heterogeneous disease. In typical Th2-type allergic asthma, interleukin (IL)-4 and IL-13 predominate, driving IgE production and recruitment of eosinophils into the lungs. Chronic Th2-inflammation in the lung results in structural changes and activation of multiple immune cell types, leading to a deterioration of lung function over time. Most immune cells express estrogen receptors (ERα, ERβ, or the membrane-bound G-protein-coupled ER) to varying degrees and can respond to the hormone. Together these receptors have demonstrated the capacity to regulate a spectrum of immune functions, including adhesion, migration, survival, wound healing, and antibody and cytokine production. This review will cover the current understanding of estrogen signaling in allergic inflammation and discuss how this signaling may contribute to sex differences in asthma and allergy.

Identification of Dutch children diagnosed with atopic diseases using prescription data: a validation study

Purpose

The aim of this study is to validate medication proxies for the identification of children diagnosed with atopic disorders that can be applied in various types of epidemiological research.

Methods

Records of 7439 children, aged between 0 and 10 years, in the period 2001 until 2010, were retrieved from the Registration Network Groningen database, a general practitioners database in the north-eastern part of the Netherlands. The sensitivity and positive predictive value (PPV) of 22 medication proxies for the identification of children diagnosed with atopic disorders (asthma, atopic dermatitis, and allergic rhinitis) were computed using the registered diagnoses as gold standards. In addition, different capture periods (1 year, half year, and length of study period) for the detection of prescriptions were tested for all the medication proxies.

Results

The highest PPV (0.84, 95 % CI 0.81–0.87) in combination with a sufficient sensitivity value (0.54, 95 % CI 0.50–0.57) for the identification of children diagnosed with asthma was yielded for the medication proxy, ≥2 prescriptions for anti-asthma medication within 1 year, including 1 inhaled steroid. PPV and sensitivity were even higher in the age group 6–10 years. The proxies designed for the identification of children diagnosed with atopic dermatitis and allergic rhinitis yielded only high PPVs (≥0.75) in combination with low sensitivity values (≤0.22). Altering the capture period for the detection of prescriptions to half a year or the length of the study period only affected sensitivity values.

Conclusion

Children diagnosed with asthma can be identified reliably with a range of medication proxies. The use of prescription data for the identification of children diagnosed with atopic dermatitis and allergic rhinitis is questionable.