World Allergy Organization-McMaster University Guidelines for Allergic Disease Prevention (GLAD-P): Probiotics

The Microbiome, Timing, and Barrier Function in the Context of Allergic Disease

Allergic disease affects millions. Despite many advances in our understanding of the immune system in the past century, the physiologic underpinning for the existence of allergy remains largely mysterious. Food allergies, in particular, have increased dramatically in recent years, adding a new sense of urgency to unraveling this mystery. The concurrence of significant lifestyle changes in Western societies with increasing disease prevalence implies a causal link. Demographic variables that influence the composition and function of the commensal microbiota early in life seem to be most important. Identifying the evolutionary and physiologic foundations of allergic disease and defining what about our modern environment is responsible for its increased incidence will provide insights critical to the development of new approaches to prevention and treatment.

Dust mite allergen, glutathione S-transferase, induces T cell immunoglobulin mucin domain-4 in dendritic cells to facilitate initiation of airway allergy

BACKGROUND

Allergens from dust mites play a critical role in the pathogenesis of airway allergy. The mechanism by which dust mite allergens induce allergic diseases is not fully understood yet.

OBJECTIVE

This study tests a hypothesis that the eighth subtypes of Dermatophagoides farina allergen (Derf8) play an important role in the induction of airway allergy.

METHODS

The protein of Derf8 was synthesized via molecular cloning approach. Dendritic cells (DC) were stimulated with Derf8 in the culture, and then, the expression of T cell immunoglobulin mucin domain 4 (TIM4) in dendritic cells (DC) was analysed. The role of Derf8 in the induction of airway allergy was evaluated with a mouse model.

RESULTS

Exposure to Derf8 markedly induced the TIM4 expression in DCs by modulating the chromatin at the TIM4 promoter locus. Derf8 played a critical role in the expansion of the T helper 2 response in the mouse airway via inducing DCs to produce TIM4. Administration with Derf8-depleted dust mite extracts (DME) inhibited the allergic inflammation and induced regulatory T cells in mice with airway allergy.

CONCLUSION

Derf8 plays an important role in the initiation of dust mite allergy. Vaccination with Derf8-deficient DME is more efficient to inhibit the dust mite allergic inflammation than using wild DME.

Food Allergy: Our Evolving Understanding of Its Pathogenesis, Prevention, and Treatment

Food allergy is defined as an IgE-mediated hypersensitivity response to ingested food with allergic symptoms ranging from urticaria to life-threatening anaphylaxis. Food allergy is thought to develop because of (1) failed induction of tolerance upon initial exposure to food antigen or (2) breakdown of established tolerance to food antigen. We review current understanding of the pathogenesis, epidemiology, and natural history of food allergy, including the unconventional IgE-mediated food allergy to mammalian meat known as alpha-gal food allergy. We highlight emerging data on food allergy treatment and prevention, emphasizing the growing appeal of manipulating the gut microenvironment using probiotics and helminth products to blunt systemic allergic responses to food.

The Use of Adjuvants for Enhancing Allergen Immunotherapy Efficacy

One key approach to increase the efficacy and the safety of immunotherapy is the use of adjuvants. However, many of the adjuvants currently in use can cause adverse events, raising concerns regarding their clinical use, and are geared toward productive immune responses but not necessarily tolerogenic responses. Thus, novel adjuvants for immunotherapy are needed and are being developed. Essential is their potential to boost appropriate tolerogenic adaptive immune responses to allergens while limiting side effects. This review provides an overview of adjuvants currently in clinical use or under development and discusses their therapeutic effect in enhancing allergen-induced tolerance.

Probiotics modulate gut microbiota and health status in Japanese cedar pollinosis patients during the pollen season

BACKGROUND

Japanese cedar pollinosis (JCP) is a challenging public health problem in Japan. Altered gut microbiota is associated with several diseases, including allergic diseases. However, only a few studies have focused on JCP and the underlying mechanisms for probiotic effects remain unclear. In addition, this study is the first observation of the correlation between the gut microbiota and blood lipid in JCP.

METHODS

Faecal samples from JCP subjects were collected before and after treatment with (n = 14) and without (n = 11) LGG-TMC0356-fermented milk for 10 weeks. Gut microbiota composition was characterized from faecal DNA using sequencing of 16S rRNA genes.

RESULTS

16S rRNA-based operational taxonomic unit clustering of the microbiota revealed that LGG-TMC0356-fermented milk significantly altered gut microbiota after 10 weeks of milk consumption, and eight dominant genera of microbes were detected. During the JCP season, the Bacteroidetes/Firmicutes ratio, when compared to baseline, was significantly decreased in subjects at end of the study. Bacteroidetes showed positive correlation with LDL- and HDL-cholesterol levels, whereas Firmicutes showed negative correlation with total cholesterol, LDL- and HDL- cholesterol.

CONCLUSIONS

The altered gut microbiota through supplementation of fermented milk containing the study probiotics may be a prospective target for protection against JCP, with beneficial effects on blood lipid levels.

Bosom Buddies: The Symbiotic Relationship Between Infants and Bifidobacterium longum ssp. longum and ssp. infantis. Genetic and Probiotic Features

The intestinal microbiota is a complex community that plays an important role in human health from the initial steps of its establishment. Its microbial composition has been suggested to result from selective pressures imposed by the host and is modulated by competition among its members. Bifidobacterium longum is one of the most abundant species of the Bifidobacterium genus in the gut microbiota of healthy breast-fed infants and adults. The recent advancements of 'omics techniques have facilitated the genetic and functional studies of different gut microbiota members. They have revealed the complex genetic pathways used to metabolize different compounds that likely contribute to the competitiveness and persistence of B. longum in the colon. The discovery of a genomic island in B. longum ssp. infantis that encodes specific enzymes for the metabolism of human milk oligosaccharides suggests a specific ecological adaptation. Moreover, B. longum is widely used as probiotic, and beneficial effects in infant health have been reported in several studies.

World Allergy Organization-McMaster University Guidelines for Allergic Disease Prevention (GLAD-P): Vitamin D

BACKGROUND

The prevalence of allergic diseases is approximately 10 % in infants whose parents and siblings do not have allergic diseases and 20-30 % in those with an allergic first-degree relative. Vitamin D is involved in the regulation of the immune system and it may play a role in the development, severity and course of asthma and other allergic diseases.

OBJECTIVE

The World Allergy Organization (WAO) convened a guideline panel to develop evidence-based recommendations addressing the use of vitamin D in primary prevention of allergic diseases.

METHODS

Our WAO guideline panel identified the most relevant clinical questions and performed a systematic review of randomized controlled trials and non-randomized studies (NRS), specifically cohort and case-control studies, of vitamin D supplementation for the prevention of allergic diseases. We also reviewed the evidence about values and preferences, and resource requirements (up to January 2015, with an update on January 30, 2016). We followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations.

RESULTS

Having reviewed the currently available evidence, the WAO guideline panel found no support for the hypothesis that vitamin D supplementation reduces the risk of developing allergic diseases in children. The WAO guideline panel suggest not using vitamin D in pregnant women, breastfeeding mothers, or healthy term infants as a means of preventing the development of allergic diseases. This recommendation does not apply to those mothers and infants who have other indications for prophylactic or therapeutic use of vitamin D. The panel's recommendations are conditional and supported by very low certainty evidence.

CONCLUSIONS

WAO recommendations about vitamin D supplementation for the prevention of allergic diseases support parents, clinicians and other health care professionals in their decisions whether or not to use vitamin D in preventing allergic diseases in healthy, term infants.

The role of the commensal microbiota in the regulation of tolerance to dietary allergens

PURPOSE OF REVIEW

We review the evidence that environmental stimuli that perturb naturally selected host-microbe interactions are driving the increasing prevalence of food allergy and examine the mechanisms by which commensal bacteria regulate tolerance to dietary allergens.

RECENT FINDINGS

Antibiotic use and the consumption of a high-fat/low-fiber diet have a major and rapid impact on gut bacterial populations, with long-term consequences for both overall microbial community structure and the regulation of host immunity. Recent work emphasizes the role of mucosa-associated commensal bacteria in eliciting a barrier-protective response critical to preventing allergic sensitization to food. Murine model studies are informing the development of novel live biotherapeutic approaches as an adjunctive therapy to enhance antigen-specific oral desensitization and to promote lasting tolerance in patients with food allergy.

SUMMARY

Strategies based on modulating the composition and/or functionality of the gut microbiome hold promise for the treatment of food allergy.

What are the indications for using probiotics in children?

The health benefits of probiotics have been the subject of extensive research. Still, some questions are being repeatedly asked: should one use or not use probiotics? If yes, how and when should probiotics be used? The purpose of this review is to summarise current evidence on specific probiotics' efficacy and safety to help healthcare professionals make evidence-based decisions on the indications for using specific probiotic strains or combinations in children. To identify relevant data, searches of MEDLINE and the Cochrane Library databases were performed in July 2015 to locate randomised controlled trials or their meta-analyses published in the last five years. The MEDLINE database also was searched for evidence-based clinical practice guidelines, developed by scientific societies. Considering that probiotics have strain-specific effects, the main focus was on data on individual probiotic strains, not on probiotics in general.

Probiotic Bacterial and Fungal Strains: Claims with Evidence

BACKGROUND

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit for the host. This review summarizes current (i.e. published in the last 5 years) key evidence on probiotic efficacy and its safety in adults and children. To identify relevant data, searches of MEDLINE and the Cochrane Library databases were performed in August 2015 to locate randomized controlled trials (RCTs) or their meta-analyses. The focus was on commonly used, well-specified, bacterial and yeast probiotics for the treatment of gastrointestinal disorders. The MEDLINE database was also searched for evidence-based clinical practice guidelines, developed by scientific societies in the same timeframe. Data on safety of probiotics were obtained from a document developed by the US Agency for Healthcare Research and Quality.

KEY MESSAGES

A number of relevant RCTs and meta-analyses are available. Saccharomyces boulardii is the most studied yeast probiotic, and Lactobacillus rhamnosus GG is the most studied bacterial probiotic. For both, the best documented fact is their efficacy for the treatment of acute gastroenteritis, especially in children, and for the prevention of antibiotic-associated diarrhea, both in adults and children. There is some evidence to support the use of probiotics to prevent or treat other diseases, such as necrotizing enterocolitis, infantile colic, Helicobacter pylori infection, and irritable bowel syndrome, but further studies are needed to identify which strain(s) is/are the most effective. Data on safety, particularly long-term safety, are limited. The risk of side effects is greater in people who have severe underlying health conditions.

CONCLUSIONS

The evidence on bacterial and yeast probiotics has considerably expanded during recent years. Accumulated data allow one to make informed decisions about the effectiveness of probiotics and about how to reduce the use of those without proven efficacy.

Probiotics and allergic diseases

The prevalence of allergic diseases including atopic dermatitis, asthma, allergic rhinitis (AR) and food allergy is increasing worldwide and they cause a big economic and social burden. Understanding of reasons that contribute to the etiology of allergic diseases as well as new treatment approaches are very important for the follow-up and prevention of these diseases. In recent years, probiotics seem to be promising for allergic diseases. The effect of probiotics in the prevention and treatment of eczema is more extensively studied, but little is known about the association of the microbial flora of the host and allergic airway diseases and the efficacy of probiotics in decreasing the symptoms of patients with asthma and rhinitis. Hitherto, there is no strong evidence for use of probiotics in the treatment of eczema; however, administration of probiotics in breastfeeding mothers in the prenatal period and infants in the postnatal period can be accepted as a safe and helpful option in the prevention of eczema. In contrast, there is not yet reliable evidence or recommendations on use of probiotics for the prevention or treatment of asthma, AR, food allergy, and anaphylaxis currently. More standardized studies should be performed with different strains of probiotics to evaluate the protective and therapeutic effects of probiotics on other allergic diseases as well as eczema. In this review, the relationship between allergy and probiotics is handled in the light of current literature.

Probiotics for treatment and primary prevention of allergic diseases and asthma: looking back and moving forward

Microbial ecosystems cover the surface of the human body and it is becoming increasingly clear that our modern environment has profound effects on microbial composition and diversity. A dysbiotic gut microbiota has been associated with allergic diseases and asthma in cross-sectional and observational studies. In an attempt to restore this dysbiosis, probiotics have been evaluated in randomized controlled trials. Here, we review treatment and primary prevention studies, recent meta-analyses, and discuss the current understanding of the role of probiotics in this context. Many meta-analyses have shown a moderate benefit of probiotics for eczema prevention, whereas there is less evidence of a benefit for other allergic manifestations. Because of very low quality evidence and heterogeneity between studies, specific advice on the most effective regimens cannot yet be given - not even for eczema prevention. To be able to adopt results into specific recommendations, international expert organizations stress the need for well-designed studies.

Probiotics: a proactive approach to health. A symposium report

This report summarises talks given at the 8th International Yakult Symposium, held on 23-24 April 2015 in Berlin. Two presentations explored different aspects of probiotic intervention: the small intestine as a probiotic target and inclusion of probiotics into integrative approaches to gastroenterology. Probiotic recommendations in gastroenterology guidelines and current data on probiotic efficacy in paediatric patients were reviewed. Updates were given on probiotic and gut microbiota research in obesity and obesity-related diseases, the gut-brain axis and development of psychobiotics, and the protective effects of equol-producing strains for prostate cancer. Recent studies were presented on probiotic benefit for antibiotic-associated diarrhoea and people with HIV, as well as protection against the adverse effects of a short-term high-fat diet. Aspects of probiotic mechanisms of activity were discussed, including immunomodulatory mechanisms and metabolite effects, the anti-inflammatory properties of Faecalibacterium prausnitzii, the relationship between periodontitis, microbial production of butyrate in the oral cavity and ageing, and the pathogenic mechanisms of Campylobacter. Finally, an insight was given on a recent expert meeting, which re-examined the probiotic definition, advised on the appropriate use and scope of the term and outlined different probiotic categories and the prevalence of different mechanisms of activity.

Allergic Patients with Long-Term Asthma Display Low Levels of Bifidobacterium adolescentis

Accumulated evidence suggests a relationship between specific allergic processes, such as atopic eczema in children, and an aberrant fecal microbiota. However, little is known about the complete microbiota profile of adult individuals suffering from asthma. We determined the fecal microbiota in 21 adult patients suffering allergic asthma (age 39.43 ± 10.98 years old) and compare it with the fecal microbiota of 22 healthy controls (age 39.29 ± 9.21 years old) using culture independent techniques. An Ion-Torrent 16S rRNA gene-based amplification and sequencing protocol was used to determine the fecal microbiota profile of the individuals. Sequence microbiota analysis showed that the microbial alpha-diversity was not significantly different between healthy and allergic individuals and no clear clustering of the samples was obtained using an unsupervised principal component analysis. However, the analysis of specific bacterial groups allowed us to detect significantly lower levels of bifidobacteria in patients with long-term asthma. Also, in allergic individuals the Bifidobacterium adolescentis species prevailed within the bifidobacterial population. The reduction in the levels on bifidobacteria in patients with long-term asthma suggests a new target in allergy research and opens possibilities for the therapeutic modulation of the gut microbiota in this group of patients.

OPINION: Primary prevention of allergy - Will it soon become a reality?

It is generally accepted that allergic diseases are not curable and not preventable, but mainly controllable using pharmacotherapy (i.e. symptomatic medication). Recent research, however, demonstrated that a number of specific interventions can lead to (partial) primary prevention of allergy, especially of atopic dermatitis (AD) and food allergy (FA). Three types of primary prevention strategies have been successfully studied: early administration of bacterial products (most studies are on probiotics), early moisturizing in infants at risk for AD and early exposure to allergenic foods (peanut and egg). Results of these studies indicate that the stage might have been set. Surely, much more research needs to be carried out before advice can be given in clinical practice. This opinion article discusses the three types of beneficial interventions and gives ideas for future research, which might show the way for better strategies in primary prevention of allergic diseases.

Probiotics for Prevention of Atopy and Food Hypersensitivity in Early Childhood: A PRISMA-Compliant Systematic Review and Meta-Analysis of Randomized Controlled Trials

Most studies investigated probiotics on food hypersensitivity, not on oral food challenge confirmed food allergy in children. The authors systematically reviewed the literature to investigate whether probiotic supplementation prenatally and/or postnatally could reduce the risk of atopy and food hypersensitivity in young children.PubMed, Embase, the Cochrane Central Register of Controlled Trials, and 4 main Chinese literature databases (Wan Fang, VIP, China National Knowledge Infrastructure, and SinoMed) were searched for randomized controlled trials regarding the effect of probiotics on the prevention of allergy in children. The last search was conducted on July 11, 2015.Seventeen trials involving 2947 infants were included. The first follow-up studies were analyzed. Pooled analysis indicated that probiotics administered prenatally and postnatally could reduce the risk of atopy (relative risk [RR] 0.78; 95% confidence interval [CI] 0.66-0.92; I = 0%), especially when administered prenatally to pregnant mother and postnatally to child (RR 0.71; 95% CI 0.57-0.89; I = 0%), and the risk of food hypersensitivity (RR 0.77; 95% CI 0.61-0.98; I = 0%). When probiotics were administered either only prenatally or only postnatally, no effects of probiotics on atopy and food hypersensitivity were observed.Probiotics administered prenatally and postnatally appears to be a feasible way to prevent atopy and food hypersensitivity in young children. The long-term effects of probiotics, however, remain to be defined in the follow-up of existing trials. Still, studies on probiotics and confirmed food allergy, rather than surrogate measure of food hypersensitivity, are warranted.

Three Novel Candidate Probiotic Strains with Prophylactic Properties in a Murine Model of Cow's Milk Allergy

Food allergies can have significant effects on morbidity and on quality of life. Therefore, the development of efficient approaches to reduce the risk of developing food allergies is of considerable interest. The aim of this study was to identify and select probiotic strains with preventive properties against allergies using a combination of in vitro and in vivo approaches. To that end, 31 strains of bifidobacteria and lactic acid bacteria were screened for their immunomodulatory properties in two cellular models, namely, human peripheral blood mononuclear cells (PBMCs) and T helper 2 (Th2)-skewed murine splenocytes. Six strains inducing a high interleukin-10 (IL-10)/IL-12p70 ratio and a low secretion of IL-4 on the two cellular models were selected, and their protective impact was tested in vivo in a murine model of food allergy to β-lactoglobulin. Three strains showed a protective impact on sensitization, with a decrease in allergen-specific IgE, and on allergy, with a decrease in mast cell degranulation. Analysis of the impact of these three strains on the T helper balance revealed different mechanisms of action. The Lactobacillus salivarius LA307 strain proved to block Th1 and Th2 responses, while the Bifidobacterium longum subsp. infantis LA308 strain induced a pro-Th1 profile and the Lactobacillus rhamnosus LA305 strain induced pro-Th1 and regulatory responses. These results demonstrate that a combination of in vitro and in vivo screening is effective in probiotic strain selection and allowed identification of three novel probiotic strains that are active against sensitization in mice.

Probiotics for allergy prevention

Probiotics, given either as a supplement or in infant foods, have been evaluated in randomised controlled trials for allergy prevention. Here, the aim is to give an overview of the results from these primary prevention studies and to discuss current strategies. In most studies, single strains or a mixture of strains of lactic acid bacteria and bifidobacteria have been used--prenatally, postnatally or perinatally. Several meta-analyses have reported a moderate benefit of probiotics for eczema prevention, and the most consistent effect has been observed with a combined perinatal intervention in infants at high risk of allergic disease due to familial predisposition. In a recent meta-analysis, the use of multi-strain probiotics appeared to be most effective for eczema prevention. No preventive effect has been shown for other allergic manifestations. As long-term follow-up data on later onset allergic conditions (asthma and allergic rhinitis) are available only from a few of the initiated studies, reports from ongoing follow-up studies that are adequately powered to examine long-term outcomes are anticipated to provide more insight. Arguably, the differences in many aspects of study design and the use of different probiotic strains and combinations have made direct comparison difficult. To date, expert bodies do not generally recommend probiotics for allergy prevention, although the World Allergy Organization (WAO) in their recently developed guidelines suggests considering using probiotics in pregnant women, during breastfeeding and/or to the infant if at high risk of developing allergic disease (based on heredity). However, in concordance with other expert bodies, the WAO guideline panel stressed the low level of evidence and the need for adequately powered randomised controlled trials and a more standardised approach before clinical recommendations on specific strains, dosages and timing can be given.

Food Allergy in childhood: phenotypes, prevention and treatment

The prevalence of food allergy in childhood increased in the last decades, especially in Westernized countries where this phenomenon has been indicated as a second wave of the allergic epidemic. In parallel, scientific interest also increased with the effort to explain the reasons of this sudden rise and to identify potential protective and risk factors. A great attention has been focused on early exposures to allergenic foods, as well as on other nutritional factors or supplements that may influence the immune system in a positive direction. Both interventions on maternal diet before birth or during breastfeeding and then directly on infant nutrition have been investigated. Furthermore, the natural history of food allergy also seems to be changing over time; IgE-mediated cow's milk allergy and egg allergy seem to be more frequently a persistent rather than a transient disease in childhood, as described in the last years. Food avoidance and the emergency drugs in case of an adverse event, such as epinephrine self-injector, are currently the first-line treatment in patients with food allergies, with a resulting impairment in the quality of life and social behaviour. During the last decade, oral immunotherapy emerged as an optional treatment with remarkable results, offering a novel perspective in the treatment for and management of food allergy.

Use of probiotics in pediatric infectious diseases

We summarize current evidence and recommendations for the use of probiotics in childhood infectious diseases. Probiotics may be of benefit in treating acute infectious diarrhea and reducing antibiotic-associated diarrhea. Potential benefits of probiotic on prevention of traveler's diarrhea,Clostridium difficile-associated diarrhea, side effects of triple therapy in Helicobacter pylori eradication, necrotizing enterocolitis, acute diarrhea, acute respiratory infections and recurrent urinary tract infections remain unclear. More studies are needed to investigate optimal strain, dosage, bioavailability of drops and tablets, duration of treatment and safety. Probiotics and recombinant probiotic strain represent a promising source of molecules for the development of novel anti-infectious therapy.

Review of Environmental Impact on the Epigenetic Regulation of Atopic Diseases

There has been significant increase in the prevalence of atopy over the past decade that cannot be explained by genetic predisposition. Environmental factors including nutrition, the uterine environment, and lifestyle factors are known to play a role in gene expression through epigenetic modifications. In this article, we review the literature on the environmental impact on epigenetic modulation of atopic diseases including asthma, food allergy, eczema, and allergic rhinitis. Recent public release of epigenomic data for hundreds of human tissues provides a powerful resource for further investigation of the molecular basis of atopic diseases.

Promising candidates for allergy prevention

Recent advances in understanding environmental risk factors for allergic diseases in children have led to renewed efforts aimed at prevention. Factors that modify the probability of developing allergies include prenatal exposures, mode of delivery, diet, patterns of medication use, and exposure to pets and farm animals. Recent advances in microbial detection techniques demonstrate that exposure to diverse microbial communities in early life is associated with a reduction in allergic disease. In fact, microbes and their metabolic products might be essential for normal immune development. Identification of these risk factors has provided new targets for prevention of allergic diseases, and possibilities of altering microbial exposure and colonization to reduce the incidence of allergies is a promising approach. This review examines the rationale, feasibility, and potential effect for the prevention of childhood allergic diseases and explores possible strategies for enhancing exposure to beneficial microbes.

Nutritional approaches for the primary prevention of allergic disease: An update

The dramatic rise in early childhood allergic diseases indicates the specific vulnerability of the immune system to early life environmental changes. Dietary changes are at the centre of lifestyle changes that underpin many modern inflammatory and metabolic diseases, and therefore are an essential element of prevention strategies. Although modern dietary changes are complex and involve changing patterns of many nutrients, there is also an interest in the early life effects of specific nutrients including polyunsaturated fatty acids, oligosaccharides (soluble fibre), antioxidants, folate and other vitamins that have documented effects on immune function as well as metabolism. A better understanding of nutritional programming of immune health, nutritional epigenetics and the biological processes sensitive to nutritional exposures in early life may lead to dietary strategies that provide more tolerogenic conditions during early immune programming and reduce the burden of many inflammatory diseases, not just allergy.

Probiotics and infantile atopic eczema

Pediatric eczema is a common disease which causes economic and social burden. Its incidence differs among the societies, with an incidence reported to reach up to 20% in developed countries. Eczema is the first allergic disease seen in the childhood, and it is recognized as a precursor for the development of atopic diseases such as asthma, allergic rhinitis, and food allergy in the forthcoming years of children. Increased incidence of eczema in recent years has led to new research in epidemiology, prevention, and intervention of this disease. It is no doubt important to treat itching, rash, and excoriation of the skin; however, treatment of pediatric eczema should not be considered only as a treatment of skin lesions. Considering skin treatment as the tip of the iceberg, proper management of the allergic processes can be accepted as the rest of the iceberg. The role of probiotics in the prevention of atopic eczema is yet to be clarified. Evidence presented by existing studies suggesting that probiotics may prevent pediatric eczema is not strong enough. A positive effect, if any, may be related with onset time, dose, duration, and use of specific probiotics. To date, there is no strong evidence for use of probiotics in the treatment of eczema; however, administration of probiotics in breast-feeding mothers in the prenatal period and in infants in the postnatal period can be accepted as a safe and helpful option in the prevention of eczema. Nevertheless, there are still questions to be answered in the future about probiotic administration for eczema. Clinical use of probiotics will gradually become more widespread when these questions are answered. Based on current information, the administration of probiotics for pediatric eczema topic is addressed in this review.

Perinatal probiotic supplementation in the prevention of allergy related disease: 6 year follow up of a randomised controlled trial

Background

Perinatal probiotics supplementation has been shown to be effective in the primary prevention of atopic dermatitis (AD) in early childhood, although the long term effects of probiotics on AD and other allergic diseases is less certain. We have previously reported a significant reduction in the cumulative incidence of AD at 2 years after maternal probiotic supplementation. In this study we present the effects of perinatal probiotics given to women from a general population on allergy related diseases in their offspring at 6 years.

Methods

Four hundred and fifteen pregnant women were randomised to receive probiotic or placebo milk in a double-blinded trial from 36 week gestation until 3 months postpartum. Probiotic milk contained Lactobacillus rhamnosos GG, L. acidophilus La-5 and Bifidobacterium animalis subsp. lactis Bb-12. At 6 years, children were re-assessed for AD, atopic sensitisation, asthma and allergic rhinoconjunctivitis (ARC).

Results

At 6 years, 81 and 82 children were assessed for AD in the probiotic and placebo groups, respectively. In a multiple imputation analysis, there was as trend towards a lower cumulative incidence of AD in the probiotic group compared to the placebo group (OR 0.64, 95 % CI 0.39-1.07, p = 0.086; NNT = 10). This finding was statistically significantly in the complete case analysis (OR 0.48, 95 % CI 0.25-0.92, p = 0.027, NNT = 6). The prevalence of asthma and atopic sensitisation, and the cumulative incidence of ARC were not significantly affected by the probiotic regime at 6 years of age.

Conclusions

Maternal probiotic ingestion alone may be sufficient for long term reduction in the cumulative incidence of AD, but not other allergy related diseases.

Trial registration

ClinicalTrials.gov identifier: NCT00159523

Electronic supplementary material

The online version of this article (doi:10.1186/s12895-015-0030-1) contains supplementary material, which is available to authorized users.

Meteorological conditions, climate change, new emerging factors, and asthma and related allergic disorders. A statement of the World Allergy Organization

The prevalence of allergic airway diseases such as asthma and rhinitis has increased dramatically to epidemic proportions worldwide. Besides air pollution from industry derived emissions and motor vehicles, the rising trend can only be explained by gross changes in the environments where we live. The world economy has been transformed over the last 25 years with developing countries being at the core of these changes. Around the planet, in both developed and developing countries, environments are undergoing profound changes. Many of these changes are considered to have negative effects on respiratory health and to enhance the frequency and severity of respiratory diseases such as asthma in the general population.

Increased concentrations of greenhouse gases, and especially carbon dioxide (CO₂), in the atmosphere have already warmed the planet substantially, causing more severe and prolonged heat waves, variability in temperature, increased air pollution, forest fires, droughts, and floods – all of which can put the respiratory health of the public at risk. These changes in climate and air quality have a measurable impact not only on the morbidity but also the mortality of patients with asthma and other respiratory diseases. The massive increase in emissions of air pollutants due to economic and industrial growth in the last century has made air quality an environmental problem of the first order in a large number of regions of the world. A body of evidence suggests that major changes to our world are occurring and involve the atmosphere and its associated climate. These changes, including global warming induced by human activity, have an impact on the biosphere, biodiversity, and the human environment. Mitigating this huge health impact and reversing the effects of these changes are major challenges.

This statement of the World Allergy Organization (WAO) raises the importance of this health hazard and highlights the facts on climate-related health impacts, including: deaths and acute morbidity due to heat waves and extreme meteorological events; increased frequency of acute cardio-respiratory events due to higher concentrations of ground level ozone; changes in the frequency of respiratory diseases due to trans-boundary particle pollution; altered spatial and temporal distribution of allergens (pollens, molds, and mites); and some infectious disease vectors. According to this report, these impacts will not only affect those with current asthma but also increase the incidence and prevalence of allergic respiratory conditions and of asthma. The effects of climate change on respiratory allergy are still not well defined, and more studies addressing this topic are needed. Global warming is expected to affect the start, duration, and intensity of the pollen season on the one hand, and the rate of asthma exacerbations due to air pollution, respiratory infections, and/or cold air inhalation, and other conditions on the other hand.

Probiotics for the prevention of allergy: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Allergic diseases are considered a health burden because of their high and constantly increasing prevalence, high direct and indirect costs, and undesirable effects on quality of life. Probiotics have been suggested as an intervention to prevent allergic diseases.

OBJECTIVE

We sought to synthesize the evidence supporting use of probiotics for the prevention of allergies and inform World Allergy Organization guidelines on probiotic use.

METHODS

We performed a systematic review of randomized trials assessing the effects of any probiotic administered to pregnant women, breast-feeding mothers, and/or infants.

RESULTS

Of 2403 articles published until December 2014 identified in Cochrane Central Register of Controlled Trials, MEDLINE, and Embase, 29 studies fulfilled a priori specified inclusion criteria for the analyses. Probiotics reduced the risk of eczema when used by women during the last trimester of pregnancy (relative risk [RR], 0.71; 95% CI, 0.60-0.84), when used by breast-feeding mothers (RR, 0.57; 95% CI, 0.47-0.69), or when given to infants (RR, 0.80; 95% CI, 0.68-0.94). Evidence did not support an effect on other allergies, nutrition status, or incidence of adverse effects. The certainty in the evidence according to the Grading of Recommendation Assessment Development and Evaluation approach is low or very low because of the risk of bias, inconsistency and imprecision of results, and indirectness of available research.

CONCLUSION

Probiotics used by pregnant women or breast-feeding mothers and/or given to infants reduced the risk of eczema in infants; however, the certainty in the evidence is low. No effect was observed for the prevention of other allergic conditions.

Probiotics and diseases of altered IgE regulation: A short review

The use of probiotics has gained considerable popularity in the marketplace in the US and has been steadily increasing due to consumer interest in potential treatment of various diseases, which may be due to modulation of immune responses. The aim of this review is to present information from representative studies regarding some of the possible applications and clinical effects of probiotic use in diseases of altered immunoglobulin (IgE) regulation (allergic rhinitis (AR), asthma, atopic dermatitis (AD) and food sensitization). Reports in humans are sparse or controversial; there is currently little reliable scientific data that supports the theory that there exists a cause-effect relationship between taking probiotics and alleviation of allergic disease. Unfortunately, these findings are too variable to allow substantial conclusions as to the efficacy and effectiveness of probiotic use in these disease states.