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

Allergic diseases are increasingly common, and it is estimated that up to 20% of the US population experiences atopic dermatitis, food allergy, asthma, allergic rhinitis, or conjunctivitis. The decrease in infectious diseases in developed countries has been associated with the risk for allergies, leading to the hygiene hypothesis for the rise of allergic disease. In order to inform World Allergy Organization guidelines, Cuello et al have examined the available data on the use of probiotics for the prevention of allergy ( J Allergy Clin Immunol 2015; 136(4):952-961 ). The composition of the gastrointestinal microbiota promotes potentially antiallergenic processes: T H 1-type immunity; generation of transforming growth factor (TGF), which has an essential role in suppressing T H 2-induced allergic inflammation and induction of oral tolerance; and IgA production, an essential component of mucosal immune defense. Alterations in these microbiota, the early and most massive source of microbi...

Atopic dermatitis in children shows an imbalance in cytokine production by their skin homing cells

While pediatric atopic dermatitis (AD) is a common disorder among children, our current understanding of its mechanisms derives largely from studies of adults with long-standing disease. Defining the similarities and differences between activated polarized T-cells in adults and in children with early-onset AD is critical for understanding initial events in disease causation. Further, a better understanding of newly diagnosed disease could help clarify the sequence of events that leads to AD development. Czarnowicki et al compare differences between T-cell memory subset activation within the skin homing and non-skin homing systemic compartments, as well as frequencies of polarized T cell subsets in blood of pediatric and adult patients with AD ( J Allergy Clin Immunol 2015; 136(4):941-951 ). Specifically, they study children with AD, children of the same age without AD, and adults with AD of similar severity. The authors find that T H 2 activation, known to induce allergy, within skin-h...

New and future strategies to improve asthma control in children

Despite advances in care, asthma presents a significant burden on the pediatric population. The age of asthma diagnosis decreased from 4.7 years in 1993 to 2.6 year in 2000. Among children given a diagnosis before the age of 3 years, 35.6% to 45.2% continue to require care for the disease at age 6, and most of them already have lung function abnormalities. Early-onset asthma has long-lasting effects that continue into adolescence and adulthood, and severe childhood asthma is a risk factor for continued active disease as an adult. To date, no therapy has been able to prevent the development of pediatric asthma, and efforts continue to focus on achieving asthma control. Anderson and Szefler review the current and future approaches ( J Allergy Clin Immunol 2015; 136(4): 848-859 ). Adherence to controller therapies is essential to achieving disease control. Pediatric adherence specifically to inhaled corticosteroids (ICSs) has been reported to fall in the range of 20% to 33.9%, with only 4...

Cockroach sensitization mitigates allergic rhinoconjunctivitis symptom severity in patients allergic to house dust mites and pollen

Allergic rhinoconjunctivitis (AR) is the most common of IgE-mediated diseases, with some surveys indicating it affects as much as 40% of the surveyed population. The familiarity of its symptoms such as itching nose, eyes, or throat; watering eyes; compromised ability to smell; and sneezing underscores its ubiquity. Patients with the same sensitivities to various allergens have wide variation in the severity of their AR symptoms. This may be due to varying allergen-concentration in each patient environment. Alternatively, the sum total of the number and kinds of aeroallergens to which one is sensitive may determine symptom severity. There is increasing evidence that supports the hygiene hypothesis as a basis for the development of allergy. This is to say that exposure early in life to certain allergens and bacteria helps to reduce AR symptoms and atopy in later life. He et al have thus investigated whether cockroach sensitization (C+) or its lack (C-), used as an indicator of childhood ...

International Consensus on Allergy Immunotherapy

Allergen immunotherapy (AIT), or the administration of an allergen with the intent of decreasing a patient’s sensitivity to it, remains underused. Numerous clinical trials show it is effective in the treatment of those with allergic rhinitis (AR), but it is estimated to be used in treatment of fewer than 10% of these patients worldwide. AIT can stop the progression of AR to asthma and it can be used to treat controlled allergic asthma. Safer and more effective AIT strategies are being developed, but ongoing barriers to its use include questions on cost-effectiveness, the need for an improved safety profile, a lack of standardization of AIT products between companies, and the lack of high quality studies regarding optimal dosing and disease-modifying potential. The subject calls for a consensus on the best AIT practice, because AIT is the only treatment that can potentially alter the progression of allergic disease and induce allergen-specific immune tolerance. To this end, the Internat...

Treatment of overlapping asthma and COPD –can guidelines contribute in an evidence-free zone?

Asthma and chronic obstructive pulmonary disease (COPD) are often clearly distinguishable diseases. There are, however, many people who demonstrate features of both. This is often termed the asthma-COPD overlap syndrome (ACOS); it is clinically important since these patients have worse health outcomes than those with either disease alone do, and some existing guidelines for treatment of either disease conflict. ACOS patients have also been specifically excluded from major clinical trials related to either condition. There is thus at this time little evidence on how to treat them, many of whom present in primary care settings. Reddel highlights the urgent need for research in this area and summarizes the interim recommendations provided in a collaborative report by Global Initiative for Asthma (GINA) and Global Initiative for chronic Obstructive Lung Disease (GOLD) ( J Allergy Clin Immunol 2015; 136(3): 546-552 ). Patients with ACOS present widely varying clinical histories, from adult ...

Therapeutic approaches to asthma-COPD overlap syndromes

While asthma and chronic obstructive pulmonary disease (COPD) are distinct clinical entities, they are often treated with the same medications. There are many patients who present with features of both diseases, a condition called asthma-COPD overlap syndrome (ACOS). ACOS is currently poorly defined or understood, and it encompasses several phenotypes that require specific therapeutic approaches. For example, there are patients with COPD who have eosinophilic inflammation that may respond to inhaled corticosteroids (ICS), or severely asthmatic patients who smoke cigarettes and have COPD inflammation. Barnes summarizes three ACOS phenotypes and addresses the therapies currently available and those in development ( J Allergy Clin Immunol 2015; 136(3): 531-545 ).  The range of phenotypes is a challenge in treating ACOS patients, and the selection of appropriate therapy requires biomarkers that are predictive of a patient’s response to them. These include blood biomarkers such as eosin...