Exacerbation Of Allergic Diseases Research Articles

The Microbial Role in Allergy: A Comprehensive Review

Background: The rise in allergic diseases in Western industrial nations has been paralleled by an increased understanding of the intricate relationship between microbial exposure and immune system responses. The hygiene hypothesis suggests a link between reduced exposure to infectious agents and an increase in allergies, emphasizing the need for a deeper investigation into the roles of various microbes in allergic reactions. Objective: This review aims to elucidate the complex mechanisms underlying allergic reactions, specifically focusing on the roles of parasites, bacteria, fungi, and viruses. It seeks to explore the potential of microbial exposure as both a protective and pathogenic factor in the development of allergies, with an eye towards informing future therapeutic strategies. Methods: An extensive literature review was conducted using databases such as Google Scholar, Scopus, PubMed, and Web of Sciences, focusing on studies published up to March 2024. The review synthesized findings on the impact of microbial exposure on allergic diseases, examining the roles of specific microbes, their interaction with the immune system, and the implications for allergic responses. Results: The review highlights the dual nature of microbial exposure in allergies, with some microbes offering protection against allergic diseases through the modulation of immune responses, while others exacerbate allergic conditions. Notably, probiotics and certain parasitic infections demonstrate potential in modulating the immune system to prevent or reduce allergic responses. Conversely, specific bacterial, fungal, and viral exposures are linked to the exacerbation of allergic diseases. Conclusion: Understanding the complex relationship between microbial exposure and allergic diseases is crucial for developing novel therapeutic and preventive strategies. This review underscores the potential of targeted microbial management in modulating immune responses to allergens, suggesting a promising avenue for reducing the global burden of allergic diseases.

Advancements in the study of allergen-specific Th2 cell surface markers

Allergen-specific Th2 cells refer to a subset of Th2 cells that undergo substantial expansion following allergen stimulation. They play a crucial role in allergic diseases, and an increasing amount of research has revealed a close relationship between surface molecules on allergen-specific Th2 cells and allergic diseases. In comparison to other CD4+T cells or Th2 cells, allergen-specific Th2 cells exhibit low expression of CD27 but high expression of CD154, CD69, CRTH2, CD161, ST2, hPGDs, CD49d, and COX-2. They can be used for the identification of allergen-specific Th2 cells and serve as potential targets for the prevention and treatment of specific diseases. They hold significant value in preventing the onset and exacerbation of allergic diseases.

Effects of indoor air quality and home environmental characteristics on allergic diseases among preschool children in the Greater Taipei Area

Indoor air quality and home environmental characteristics are potential factors associated with the onset and exacerbation of allergic diseases. Our study examined the effects of these factors on allergic diseases (i.e., asthma, allergic rhinitis, allergic conjunctivitis, and atopic dermatitis) among preschool children. We recruited a total of 120 preschool children from an ongoing birth cohort study in the Greater Taipei Area. A comprehensive environmental evaluation was conducted at each participant's residence and included measurements of indoor and outdoor air pollutants, fungal spores, endotoxins, and house dust mite allergens. A structured questionnaire was used to collect information on the allergic diseases and home environments of participants. Land-use characteristics and points of interest in the surrounding area of each home were analyzed. Other covariates were obtained from the cohort data. Multiple logistic regressions were used to examine the relationships between allergic diseases and covariates. We observed that all mean indoor air pollutant levels were below Taiwan's indoor air quality standards. After adjustment for covariates, the total number of fungal spores and the ozone, Der f 1, and endotoxin levels were significantly associated with increased risks of allergic diseases. Biological contaminants more significantly affected allergic diseases than other pollutants. Moreover, home environmental characteristics (e.g., living near power facilities and gas stations) were associated with an increased risk of allergic diseases. Regular and proper home sanitation is recommended to prevent the accumulation of indoor pollutants, especially biological contaminants. Living away from potential sources of pollution is also crucial for protecting the health of children.

Management of patients with allergic diseases in the era of COVID-19.

In the early days of the coronavirus disease 2019 (COVID-19) pandemic, allergic diseases, especially asthma, were considered to be risk factors for severe COVID-19 infection, hospitalization, and death. These concerns stemmed from the idea that individuals with allergic diseases are generally more susceptible to respiratory virus infections, which are major causes of exacerbation of allergic diseases. However, epidemiologic data with mechanistic studies showed that the associations between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and clinical outcomes of allergic diseases are complex and affected by diverse factors such as allergic disease severity, phenotypes, and control status with current medications. In addition, children generally have less severe clinical outcomes of COVID-19 than those of adults, which complicates the association between allergic diseases and COVID-19-related outcomes among them. The present review summarizes the potential association between allergic diseases and COVID-19-related outcomes and discusses the factors requiring consideration. The findings viewed herein will aid the management of allergic diseases in patients with SARS-CoV-2 infection and the establishment of medical polices for managing patients with allergic diseases.

Complex Approach to Diagnosis of Nasal Cavity and Nasopharyngeal Pathologies in Children. Initial Results

Background. Nasal cavity and nasopharyngeal pathology are crucial and common issue in pediatric otorhinolaryngology. One of the major reasons for the nasal breathing difficulties are adenoids, allergic rhinitis, acute rhinitis, rhinosinusitis, nasal septum deviation. All these diseases can occur individually and in combination with each other, while clinical signs can be similar.Objective. The aim of the study is study and estimate the condition of nasal breathing and sense of smell in children with different nasal and nasopharyngeal pathology.Methods. The study included 128 children, all children were divided into 3 groups comparable by gender and age. Children with confirmed acute ENT organ disease were included in the 1st group, children with allergic disease exacerbation were included in the 2nd group, and clinically healthy children (control group) were included in the 3rd group. Survey methodology: rhinomanometry (RMM), rhinoresistometry (RRM), olfactometry.Results. It was revealed that nasal resistance in children with allergic diseases exacerbation is significantly higher both before and after anemisation of nasal mucosa with a solution of nasal decongestants than in children of the control group (according to the RRM). The air flow rate increases by average of 25% in children with various ENT organs diseases, and in children with allergic diseases — by average of 43% after anemisation of the nasal mucosa. The obtained data shows the role of nasal mucosal edema in patients with allergic diseases during exacerbation. Analysis of our RMM and RRM data suggests the importance of further use of these methods in children.Conclusion. The obtained results will allow us to optimize the diagnosis approach and personalize the management of patients with various nasal cavity and nasopharynx pathologies. Nowadays, the study is ongoing.

Environmental exposures: evolving evidence for their roles in adult allergic disorders.

Allergic disorders are the result of complex interactions between genetic predisposition and environmental exposures. Elucidating how specific environmental exposures contribute to allergic diseases in adults is crucial, especially as the world population ages in a rapidly changing environment. The effects of environmental exposures on allergic diseases remain understudied in adults. Although epidemiological studies suggest various environmental exposures are associated with the development and exacerbation of allergic diseases, further longitudinal studies are needed across various age groups in adults to pinpoint the exposures of concerns and the time windows of susceptibility. Mechanistic studies in adults are few. A multicomponent strategy targeting several allergens has been conditionally recommended for asthma, but recent findings on mitigation strategies remain limited. Further research on how environmental exposures cause and exacerbate allergic disorders is needed in adults, particularly across disease phenotypes. The effects of mitigation strategies against environmentally induced adult allergic diseases remain large research gaps. A better understanding of how and which environmental exposures contribute to allergic disorders is necessary to identify patients who are at higher risk and would benefit from specific interventions.

The role of human β-defensin 2 (HbD-2) and cathelicidin (LL-37) in the local protection of the upper respiratory tract in children with allergic rhinitis and bronchial asthma

Allergic diseases of the respiratory system seriously affect the psychological, physical and social aspects of the live of sick children, morally and financially exhausting members of their families as well. It is known that exacerbations of allergic diseases of the respiratory tract occur due to interaction with numerous triggers, one of which is a respiratory viral infection. At the same time, it is widely known that patients with allergic respiratory diseases are more prone to to acute respiratory infections. One of the reasons for this tendency often is an insufficient activity of non-specific factors of local immunity of the respiratory system – endogenous amphiphilic antimicrobial peptides, in particular the most studied their representatives - the family of defensins and human cathelicidin. Current research proves that these antimicrobial peptides are characterized by broad antiviral, antimicrobial and immunomodulatory activity. The aim of this study was to study the concentrations of local immune factors - human HbD-2 and LL-37 - in the secretion of the mucous membranes of the upper respiratory tract in children with asthma and allergic rhinitis and to clarify their role in protection against respiratory viral infections in this contingent of patients. We performed laboratory and clinical examinations of 76 children aged 7 to 18 years, of whom 24 were diagnosed with allergic rhinitis, 28 children - bronchial asthma, and 24 - bronchial asthma and allergic rhinitis. The control group consisted of 20 healthy children of the appropriate sex and age. In addition to general clinical methods, patterns of respiratory morbidity were analyzed and concentrations of antimicrobial peptides were determined: by ELISA human cathelicidin (LL-37), β-defensin 2 (HbD-2) in the secretion of the upper respiratory tract, statistical analysis was performed. It was found that children with allergic diseases of the respiratory tract are characterized by a higher frequency of acute respiratory infections with more frequent involvement of the lower respiratory tract, which led to an increase in the duration of the disease compared to their healthy peers. In children with allergic rhinitis and bronchial asthma, there was revealed a significant decrease in the concentrations of antimicrobial peptides in the secretion of the upper respiratory tract compared with the control group.

Secondary and Tertiary Prevention: Medical Rehabilitation.

Allergies are a major public health burden, and targeted measures are required in terms of prevention and treatment. The most common allergic conditions encompass atopic dermatitis (AD), food allergy (FA), allergic asthma (AA), and allergic rhino-conjunctivitis (AR). Primary prevention aims at preventing the onset of allergic disease, before the disease process begins. Secondary prevention aims at preventing progression and exacerbation of allergic disease whereas tertiary prevention aims at reducing disease burden in patients with established disease, by allergen immunotherapy (AIT) or medical rehabilitation. Rehabilitation programs are used for treatment of AA and AD and usually consist of extensive patient assessment, optimization of treatment management, patient education, and behavioral interventions, ideally involving a multidisciplinary treatment team and sometimes provided in a specific climate, usually alpine or maritime. Similarly, prevention of occupational skin diseases requires interdisciplinary approaches on the level of secondary and tertiary preventive intervention; if this is provided, then prevention programs have proven highly (cost-) effective. Unfortunately, the recently published Minimal Standards of Prevention of these dermatoses, underlining especially the importance of meticulous allergological diagnosis and subsequent multidisciplinary patient education, are so far being adhered to only in very few European countries.

IgE-mediated regulation of IL-10 and type I IFN enhances rhinovirus-induced Th2 differentiation by primary human monocytes.

Rhinovirus (RV) infections are linked to the development and exacerbation of allergic diseases including allergic asthma. IgE, another contributor to atopic disease pathogenesis, has been shown to regulate DC antiviral functions and influence T cell priming by monocytes. We previously demonstrated that IgE-mediated stimulation of monocytes alters multiple cellular functions including cytokine secretion, phagocytosis, and influenza-induced Th1 development. In this study, we investigate the effects of IgE-mediated stimulation on monocyte-driven, RV-induced T cell development utilizing primary human monocyte-T cell co-cultures. We demonstrate that IgE crosslinking of RV-exposed monocytes enhances monocyte-driven Th2 differentiation. This increase in RV-induced Th2 development was regulated by IgE-mediated inhibition of virus-induced type I IFN and induction of IL-10. These findings suggest an additional mechanism by which two clinically significant risk factors for allergic disease exacerbations-IgE-mediated stimulation and rhinovirus infection-may synergistically promote Th2 differentiation and allergic inflammation.

P4454N-terminal pro-brain natriuretic peptide and resistance to chronic therapy with 75 mg acetylsalicylic acid assessed by point-of-care test - prospective single center study

Abstract Background Acetylsalicylic acid (ASA) remains the principal medication for secondary prevention of atherosclerotic complications. Resistance to ASA (ASAres) is multifactorial and results in insufficient reduction of platelet reactivity through incomplete inhibition of thromboxane A2 (TXA2) synthesis. There is controversy regarding the optimal preventive ASA dose with common daily use of 75 mg in many European countries. Purpose The aim of our study is to reassess the prevalence and predictors of ASAres in contemporary cohort of coronary disease (CAD) patients (pts) on stable therapy with 75 mg ASA. Methods We studied 205 patients (36,6% females) with stable CAD and concomitant atherosclerotic disease history (ischemic stroke 10,2%, peripheral vascular disease 8,3%,) and type 2 diabetes in 39,5% on stable regimen 75 mg ASA for a minimum of 1 month (mean age 68,2±9,7 years, mean BMI 27,3±4,7 kg/m2). ASAres was defined as ARU (aspirin reaction unit) ≥550 using point-of-care VerifyNow Aspirin test. Exclusion criteria were: recent (up to 2 months) acute coronary syndrome, cancer, dermatological disease, epilepsy or other chronic neurological diseases, exacerbation of allergic disease, rheumatoid arthritis, periodontal disease, alcoholism, drug addiction, vegetarianism, veganism and other specific diets, and known thrombophilia. The population received standard concomitant preventive treatments including RAA blockade in 88,3%, beta-blockers in 85,9%, statins in 93,2%, and proton pump inhibitors (PPI) in 65,4%. History of infarction was present in 37% and mean left ventricular ejection fraction was 47% (18–75%). Results ASAres was detected in 11,7% of patients. Modest but significant correlations (Spearman's coefficient of rank correlation rho) were detected between ARU and C-reactive protein (CRP) (rs=0,15; p=0,030), N-terminal pro-brain natriuretic peptide (NT-proBNP) (rs=0,15; p=0,039), body weight (rs=0,22; p=0,0014), BMI (rs=0,207, p=0,0029). No significant differences in ASAres we found with regard to sex, other risk factors or concomitant medication, including PPI. However, in ASAres pts median concentrations of NT-proBNP were significantly higher (median 311 vs. 646pg/ml; p=0,046). In multivariate analysis NT-proBNP emerged as the only independent predictor of ASAres (AUC=0,626; p=0,027 with threshold value of 327,3 pg/ml resulting with negative predictive value of 16,98% and positive predictive value of 93,95% for ASAres). Conclusion ASAres has significant prevalence in this secondary prevention CAD cohort treated with 75 mg daily dose. NT-proBNP was identified as the only independent predictor in multivariate analysis. This finding may be important especially for pts with heart failure of ischemic etiology. The implications of switching into 100 mg or higher ASA doses remain to be investigated. Acknowledgement/Funding study was supported from unrestricted research grant from Aflofarm SA

Air pollutants and primary allergy prevention

Abstract Background Air pollutants such as particulate matter (PM2.5) and nitrogen dioxide (NO2) in outdoor air have long been suspected of causing the development of asthma and allergic rhinitis. However, a variety of systematic reviews have reached different conclusions in the last 15 years on whether these air pollutants do in actual fact play a causal role in the onset of asthma, allergic rhinitis, and eczema. Methods Based on published systematic reviews and the most recent publications, the current state of knowledge on epidemiological evidence is presented and the potential for primary prevention of these allergic diseases by reducing or avoiding exposure to these air pollutants evaluated. Results Despite conducting an extensive literature search, analyzing the most recent results, and focusing on the birth cohort studies most relevant to the question in hand, epidemiological results do not adequately support the concept of a causal relationship between the two air pollutants in question, PM2.5 and NO2, and asthma. Epidemiological studies predominantly show no effect of these air pollutants on allergic sensitization and the onset of allergic rhinitis. The small number of studies that have investigated the link between air pollutants and eczema largely revealed there to be no link. Conclusion If the evidence for the causal role of air pollutants in the onset of allergies is inconclusive, one must assume that it is probably not possible to achieve primary prevention of allergies by improving air quality. However, there is sufficient evidence to show that air pollutants can trigger exacerbations of allergic diseases. This alone justifies ensuring that the existing threshold values for air pollutants are adhered to, in order to protect particularly allergy sufferers from health impairments.

First Results of Assessing the Quality of Medical Care at Pre-Hospital and Hospital Stages for Children with Acute Allergic Pathology

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Contribution of engineered nanomaterials physicochemical properties to mast cell degranulation

The rapid development of engineered nanomaterials (ENMs) has grown dramatically in the last decade, with increased use in consumer products, industrial materials, and nanomedicines. However, due to increased manufacturing, there is concern that human and environmental exposures may lead to adverse immune outcomes. Mast cells, central to the innate immune response, are one of the earliest sensors of environmental insult and have been shown to play a role in ENM-mediated immune responses. Our laboratory previously determined that mast cells are activated via a non-FcεRI mediated response following silver nanoparticle (Ag NP) exposure, which was dependent upon key physicochemical properties. Using bone marrow-derived mast cells (BMMCs), we tested the hypothesis that ENM physicochemical properties influence mast cell degranulation. Exposure to 13 physicochemically distinct ENMs caused a range of mast degranulation responses, with smaller sized Ag NPs (5 nm and 20 nm) causing the most dramatic response. Mast cell responses were dependent on ENMs physicochemical properties such as size, apparent surface area, and zeta potential. Surprisingly, minimal ENM cellular association by mast cells was not correlated with mast cell degranulation. This study suggests that a subset of ENMs may elicit an allergic response and contribute to the exacerbation of allergic diseases.

Clinical and immunological efficacy of immunoprophylaxis of influenza in children with allergic diseases

Despite the fact that according to the guidelines of the World Health Organization all patients with allergic disorders should be annually vaccinated against influenza, regardless of the form or severity of the disease and ongoing drug therapy, that is still not applicable in practice. This fact entails at least two negative outcomes: the risk of infectious disease and its complications, as well as increased likelihood of exacerbation of the allergic disease against a background of the intercurrent infection. The aim of the study was to investigate the effectiveness and tolerability of domestic and foreign vaccines against the flu in children with allergic diseases. The study demonstrated good tolerability of the researched vaccines, absence of evident local and/or systemic reactions and of exacerbations of allergic diseases. The study found that vaccination completely protects children from the flu and significantly reduces the incidence of ARI, leading to an increase in the remission period and lower incidence of exacerbations of the underlying disease.

Levels and determinants of tree pollen in New York City.

Exposure to allergenic tree pollen is a risk factor for multiple allergic disease outcomes. Little is known about how tree pollen levels vary within cities and whether such variation affects the development or exacerbation of allergic disease. Accordingly, we collected integrated pollen samples at uniform height at 45 sites across New York City during the 2013 pollen season. We used these monitoring results in combination with adjacent land use data to develop a land use regression model for tree pollen. We evaluated four types of land use variables for inclusion in the model: tree canopy, distributed building height (a measure of building volume density), elevation, and distance to water. When included alone in the model, percent tree canopy cover within a 0.5 km radial buffer explained 39% of the variance in tree pollen (1.9% increase in tree pollen per one-percentage point increase in tree canopy cover, P<0.0001). The inclusion of additional variables did not improve model fit. We conclude that intra-urban variation in tree canopy is an important driver of tree pollen exposure. Land use regression models can be used to incorporate spatial variation in tree pollen exposure in studies of allergic disease outcomes.

Indoor air quality and atopic sensitization in primary schools: A follow-up study

BackgroundThe onset and exacerbation of allergic diseases and asthma have been associated with poor indoor air quality (IAQ) inside classrooms. ObjectiveThe aim was to investigate how IAQ changed in primary schools after applying indoor air quality recommendations, and to explore how these changes influenced allergic sensitization on children. MethodsTotal volatile organic compounds, PM2.5, PM10, CO2, CO, temperature and relative humidity in the indoor and outdoor air of 20 primary schools were measured in 2010–2012. The school staff received instructions on how to improve IAQ in accordance with the dedicated guidelines. Atopy status was assessed in children attending the participating classrooms by skin prick tests and exhaled nitric oxide. A follow-up sampling campaign was performed in 2014–2015 in the same schools. ResultsIndoor PM2.5 and PM10 concentrations were approximately 40% lower in the follow-up measurements (p<0.05). There were no significant differences regarding outdoor PM concentrations. Nevertheless, PM levels from the follow-up campaign still exceeded the reference value established by Portuguese legislation. Moreover, there were no significant differences in atopic prevalence and FENO values between the campaigns. ConclusionThese findings suggest that adoption of the recommendations based on the SINPHONIE guidelines was particularly successful in reducing PM2.5 and PM10 in primary schools of Porto. Nevertheless, the schools failed to reduce the levels of other IAQ pollutants, as well as the prevalence of atopic disease.

Protease activity of Per a 10 potentiates Th2 polarization by increasing IL-23 and OX40L.

Proteases are implicated in exacerbation of allergic diseases. In this study, the role of proteolytic activity of Per a 10 was evaluated on Th2 polarization. Intranasal administration of Per a 10 in mice led to allergic airway inflammation as seen by higher IgE levels, cellular infiltration, IL-17A, and Th2 cytokines, whereas, inactive (Δ)Per a 10 showed attenuated response. There was an increased OX40L expression on lung and lymph node dendritic cells in Per a 10 immunized group and on Per a 10 stimulated BMDCs. Reduction in CD40 expression without any change at transcript level in lungs of Per a 10 immunized mice suggested CD40 cleavage. BMDCs pulsed with Per a 10 showed reduced CD40 expression with lower IL-12p70 secretion as compared to heat inactivated Per a 10. IL-23, TNF-α, and IL-6 levels were significantly higher in Per a 10 stimulated BMDCs supernatant. In DC-T cell coculture studies, Per a 10 pulsed BMDCs showed higher levels of IL-4 and IL-13 that were reduced on blocking of either IL-23 or OX40L. In conclusion, the data suggests a critical role of protease activity of Per a 10 in promoting Th2 polarization by increasing IL-23 secretion and OX40L expression on dendritic cells.

Identification of critical control points for safety management of production of frozen fish

The features of the introduction of the safety management system HACCP in Ukrainian fish processing enterprises were considered. A full analysis of hazards occurring in the production of frozen fish was performed and it was determined that quality control in fish industry enterprises is carried out by production-veterinary control departments (PVCD), which include veterinary service specialists, chemists, bacteriologists. PVCD allow sales of fish products only if their quality characteristics meet the requirements of GOST or TU. Before the introduction of the safety management system of food products, safety working group conducts research for each type (group) of products according to DSTU 4161-2003 and registers them in certain safety protocols. Critical control points for safety management of production of frozen fish were developed. Hazard analysis and identification of CCP of production of frozen fish in fish processing enterprises revealed that the most serious stage is acceptance of live fish, because biological and chemical factors are significant and can lead to diseases common to fish and humans, or development or exacerbation of allergic diseases. The stage of fish storage: observance of temperature conditions and shelf life is also important.

Relationship between Abundance of Risk Factors and Prevalence of Asthma and Allergic Disease at South of Cairo

Many studies have focused on environmental exposures among inner city subject with asthma, allergen exposure potentially leading to a higher prevalence of asthma and it has been suggested as among causes. In this study we investigate the relation between risk factors (exposure to air pollutions, family history and exposure to family pets or far animals), and asthma and other allergic disease exacerbation, and indicate the severity of like this diseases.

Development Of A Land Use Regression Model For Tree Pollen Exposure

Background: Little is known about how tree pollen varies within cities or whether spatial variation in pollen contributes to the development or exacerbation of allergic disease. We developed a land use regression (LUR) model for tree pollen that can be used to estimate exposure information for epidemiologic studies. Methods: We measured pollen at 45 sites within a U.S. city using modified Tauber traps placed 8 feet off the ground. We collected integrated samples for the entire pollen season of 2013 (March through October). We evaluated four types of variables characterized at five radial buffer sizes (50, 100, 250, 500, and 1,000 meters) for inclusion in an LUR model for log-transformed total tree pollen: tree canopy, building density, elevation, and traffic density. We also evaluated the distance to water for each monitoring site. For each variable that was significantly correlated with tree pollen, we passed the most highly correlated buffer size on to the LUR. We evaluated model performance using leave-one-out cross validation (LOOCV) and the root mean squared error (RMSE). Results: Tree canopy and elevation were significantly positively correlated with tree pollen, while building density was significantly negatively correlated with tree pollen. When included alone in the LUR, the most highly correlated tree canopy buffer size (500 meters) explained nearly 40% of the variance of tree pollen (β1 for a 1% increase in tree canopy = 0.019, p for β1 &lt; 0.0001, R2 = 0.388, RMSE from LOOCV = 0.319). Additional variables did not improve model fit. Kriging techniques did not improve model fit for total tree pollen, but were successful in predicting several individual tree pollen taxa. Conclusions: Tree canopy within a 500 meter radial buffer is an important predictor of intra-urban tree pollen exposure. Future work will estimate pollen exposures for children in an asthma study population to examine the effects of spatial variation in tree pollen on allergic disease outcomes.