Effect of area of residence on patterns of aeroallergen sensitization in atopic patients

Environmental allergen reduction in asthma management: an overview

Asthma is a prevalent non-communicable disease that affects both children and adults. Many patients with severe, uncontrolled asthma could not achieve total control despite using anti-asthmatic drugs. There is increasing evidence that allergy to environmental allergens, including both indoor and outdoor allergens, is associated with asthma symptoms and severe asthma. Frequently reported sensitized allergens were dust mites, cockroaches, grass pollens, molds, pets, and rodents in allergic asthma patients, although the patterns of widespread allergens differed from each country. Allergen avoidance is the cornerstone of asthma management, especially in sensitized subjects. This review summarizes environmental allergen avoidance and clarifies their effects on asthma control. Despite contrasting results about the impact of allergen exposure reduction on asthma control, several studies supported the beneficial effects of reducing asthma-related symptoms or risk of exacerbations as a nondrug therapy. Identifying environmental allergens is helpful for asthma patients, and further studies on clinically effective avoidance methods are required.

Allergic rhinitis in India

India is the home of nearly 20% of the global population with 1.35 billion people. Of all non-communicable diseases, allergic diseases such as allergic rhinitis (AR) and asthma appear to have increased in India over the past decades. Approximately 22% of adolescents currently suffer from AR in India. However, owing to the lack of adequate epidemiological studies in India, particularly in rural and suburban areas, this number may misrepresent the true burden of this disease. While the risk factors for AR are mainly environmental exposures or genetic factors, several new environmental, social, and behavioural risk factors such as the presence of dumpsters near residences, movement of vehicles near homes, and exposure to artificial light at night have been found to be associated with AR. However, despite international guidelines, the diagnosis and management of AR in India are often suboptimal, for multiple reasons such as the lack of specialized training in allergy and immunology among Indian clinicians, the lack of diagnostic facilities, and the high cost of medications. This review aims at highlighting the current scenario of AR in India and how it differs from the rest of the world. It also highlights the need for developing a strategic approach to enhance the quality of care for allergic diseases by upgrading education and training for healthcare professionals, creating awareness among clinicians and patients, and involving stakeholders and policymakers in making treatments accessible and affordable to patients.

Allergic diseases in India - Prevalence, risk factors and current challenges

Epidemiological studies have shown a rise in the prevalence of allergic diseases in India during the last two decades. However, recent evidence from the Global Asthma Network study has observed a decrease in allergic rhinitis, asthma and atopic dermatitis in children. Still, with a population over 1.3 billion, there is a huge burden of allergic rhinitis, asthma and atopic dermatitis, and this is compounded by an unmet demand for trained allergy specialists and poor health service framework. There is wide variation in the prevalence of allergic diseases between different geographical locations in India, and the reasons are unclear at present. This may at least in part be attributable to considerable heterogeneity in aero-biology, weather, air pollution levels, cultural and religious factors, diet, socioeconomic strata and literacy. At present, factors enhancing risks and those protecting from development of atopy and allergic diseases have not been well delineated, although there is some evidence for the influence of genetic factors alongside cultural and environmental variables such as diet, exposure to tobacco smoke and air pollution and residence in urban areas. This narrative review provides an overview of data from India regarding epidemiology, risk factors and genetics and highlights gaps in evidence as well as areas for future research.

Skin Prick Test Reactivity to Common Allergens among Allergic Rhinitis Patients in Kocaeli Province, Turkey

Objective: The identification of the most common aeroallergens causing allergic rhinitis (AR) in a specific geographic area is important in the diagnosis and treatment of AR. This study evaluates the prevalence of sensitivity to aeroallergens among patients with AR who live in Kocaeli province, Turkey. Methods: This cross-sectional, descriptive study included a retrospective review of skin prick test (SPT) results from patients with suspected AR who were examined at a tertiary hospital rhinology clinic. Results: The SPT results of 85 patients with an AR diagnosis were included in this study. House dust mites (HDM) had the highest frequency of positive test responses (57.6%), followed by tree pollen (40.0%), grass pollen (36.5%), weed pollen (32.9%), cockroach (18.8%), animal dander (14.1%), and mold (11.8%). The majority of the AR patients were polysensitized (57.6%), and the most common allergens in polysensitized patients were tree pollen (61.2%), grass pollen (57.1%), and HDM (55.1%), respectively. The strongest single allergen in monosensitized subjects was HDM, with a rate of 61.1%. Conclusion: The most prevalent allergen was HDM among AR patients in the Kocaeli region, followed by tree pollen and grass pollen. Polisensitization occurs more frequently than monosensitization. These allergens should be prioritized in the diagnosis and treatment of allergic rhinitis in Kocaeli region patients.

Fungal Aeroallergen Sensitization Patterns among Airway-Allergic Patients in Zagazig, Egypt

BACKGROUND

Airway allergies such as asthma and allergic rhinitis, as well as their comorbidities, are increasing worldwide, causing significant socioeconomic health burdens to societies. It is estimated that between 3% and 10% of the population is allergic to fungi. The type of fungal sensitization varies from one geographical region to another. The present study aimed to identify the common fungal aeroallergen sensitization patterns among airway-allergic patients residing in the Zagazig locality, Egypt, in order to obtain a better understanding of fungal allergy, in addition to improving the awareness and management strategies for those patients.

METHODS

The present cross-sectional study included 200 allergic rhinitis and asthma patients. Sensitization to fungal aeroallergens was evaluated by skin prick testing and in vitro measurement of total and specific immunoglobulin E.

RESULTS

As determined by a skin prick test, 58% of the patients studied were allergic to mixed molds. Alternaria alternata was the predominant fungal aeroallergen among the studied patients (72.2%), which was followed by Aspergillus fumigatus (53.45%), Penicillium notatum (52.6%), Candida albicans (34.5%), and Aspergillus niger (25%).

CONCLUSION

Mixed mold sensitization ranked fourth among the most frequent aeroallergens in airway-allergic patients, and Alternaria alternata was the most frequently encountered fungal aeroallergen in the Zagazig locality.

An appraisal of allergic disorders in India and an urgent call for action

India is the second most populous country in the world with a population of nearly 1.3 billion, comprising 20% of the global population. There are an estimated 37.5 million cases of asthma in India, and recent studies have reported a rise in prevalence of allergic rhinitis and asthma. Overall, 40-50% of paediatric asthma cases in India are uncontrolled or severe. Treatment of allergic rhinitis and asthma is sub-optimal in a significant proportion of cases due to multiple factors relating to unaffordability to buy medications, low national gross domestic product, religious beliefs, myths and stigma regarding chronic ailment, illiteracy, lack of allergy specialists, and lack of access to allergen-specific immunotherapy for allergic rhinitis and biologics for severe asthma. High quality allergen extracts for skin tests and adrenaline auto-injectors are currently not available in India. Higher postgraduate specialist training programmes in Allergy and Immunology are also not available. Another major challenge for the vast majority of the Indian population is an unacceptably high level of exposure to particulate matter (PM)_2.5 generated from traffic pollution and use of fossil fuel and biomass fuel and burning of incense sticks and mosquito coils. This review provides an overview of the burden of allergic disorders in India. It appraises current evidence and justifies an urgent need for a strategic multipronged approach to enhance quality of care for allergic disorders. This may include creating an infrastructure for education and training of healthcare professionals and patients and involving regulatory authorities for making essential treatments accessible at subsidised prices. It calls for research into better phenotypic characterisation of allergic disorders, as evidence generated from high income western countries are not directly applicable to India, due to important confounders such as ethnicity, air pollution, high rates of parasitic infestation, and other infections.

Assessment of Hymenoptera and Non-Hymenoptera Insect Bite and Sting Allergy Among Patients of Tropical Region of West Bengal, India

West Bengal, India, is inhabited by abundance and variety of insects that triggers sensitization in some humans to inhalant allergens and/or insect stings/venoms. Lack of research on this topic prevented accurate diagnosis and proper follow-up treatments to patients suffering from insect-induced allergies. The aim of our study was to identify the allergy-causing insects and evaluate resulting sensitization among a study population in West Bengal, India. The skin prick test (SPT) evaluated sensitivity of 450 patients who sought treatment at the Allergy and Asthma Research Center from July 2017 to June 2018. Eight insect allergens were tested: Common Black Ant (Lasius niger, Linnaeus 1758), Fire Ant (Solenopsis invicta, Buren 1972), Honey Bee (Apis cerana indica, Fabricius 1798), Common Wasp (Vespula vulgaris, Linnaeus 1758), Mosquito (Aedes aegypti, Linnaeus in Hasselquist 1762), American Cockroach (Periplaneta americana, Linnaeus 1758), House Fly (Musca domestica, Linnaeus 1758), and Grasshopper (Gesonula punctifrons, Stal 1861). From a total of 450 patients evaluated, 370 patients had positive SPT reaction from at least one of the 8 insect allergens tested. Sensitivity to some Hymenoptera insects (common black ant, 87.62%; fire ant, 84.59%; and honey bee, 67.02%) was found in higher proportion than non-Hymenoptera group (mosquito, 66.67%; American cockroach, 33.33%; house fly, 10.41%; and grasshopper, 5.14%). There was significant difference in sensitivity among child, adolescent, and adult (P < 0.001). While female patients showed more sensitivity than males to SPT, the difference was statistically insignificant. In regards to occupation, farmers and bee keepers were most sensitive of field workers sensitive to Hymenoptera-derived allergens.

Retrospective analysis of aeroallergen's sensitization patterns in Edmonton, Canada

Background

Sensitization to common environmental aeroallergens plays a significant role in the pathogenesis and severity of respiratory allergic disorders, specifically asthma and allergic rhinitis. Understanding sensitization patterns helps clinicians tailor care more effectively. This study examines patterns of sensitization to aeroallergens in subjects suspected of having an allergic disease in Edmonton and catchment area.

Methods

Retrospective chart review of skin prick test (SPT) results to 11 environmental aeroallergens performed between January 1st and June 30th 2014 at a University-based clinic, where patients are referred for SPT by allergists, respirologists, otolaryngologists, internists and general practitioners. Potential differences in aeroallergen sensitization patterns were evaluated.

Results

A total of 623 patients (36.9% males; 63.1% females), aged 4–84 years (mean age 38.6 years) had SPT done, of which 438 (70.3%) had a positive test for at least one aeroallergen (atopy). There were no significant sex differences in the frequency of atopy (males: 71.3% versus females: 69.7%; p = 0.373). The frequency of sensitivity to particular allergens among atopic subjects was: cat (53.1%), house dust mites (50.3%), grass (39.2%), birch (23.7%), alternaria (23.7%), dog (17.3%), poplar (12.1%), cedar (9.6%), aspergillus (9.6%), hormodendrum (8%), and penicillium (6.2%). Of 438 atopic patients, 110 (25.1%) were mono sensitized, 199 (45.4%) oligosensitized (2–3 allergens), and 129 (29.5%) polysensitized (≥ 4 allergens). There were no significant differences between males and females in the odds of being oligo-sensitized (OR: 0.95; 95% CI 0.58, 1.57). Polysensitization was significantly more frequent in males 37.2% than in females 24.8%; (OR: 0.95; 95% CI 0.58, 1.57).

Conclusion

Cat is the most frequent perennial allergen and timothy grass pollen the most frequent seasonal allergen in Edmonton and catchment area. There was no significant difference in the frequency of atopy between males and females. However, males were more likely to be polysensitized compared to females.

Ragweed allergy: Pollen count and sensitization and allergy prevalence in two Italian allergy centers

BACKGROUND

Ragweed allergy represents a challenge for allergists due to its increase in some geographic areas, mainly northern Italy.

OBJECTIVES

To compare two allergy centers in northern Italy by analyzing both the pollen count and the patient characteristics (sensitization and allergy prevalence) over a 10-year period.

METHODS

Pollen counts for 10 years (2004-2013) were evaluated and compared in the two centers. Characteristics of patients who were sensitized and allergic to ragweed were analyzed.

RESULTS

There was a significantly higher pollen count in Busto Arsizio than in Novi Ligure (p < 0.001). The patients who were seen in the Busto Arsizio center showed more frequent sensitization (p < 0.01) and allergy (p < 0.05) to ragweed than patients who were seen in the Novi Ligure center. The pollen count was significantly (p < 0.01) associated with sensitization and allergy difference. Allergic asthma was more frequent (p < 0.05) in Busto Arsizio.

CONCLUSIONS

The pattern of sensitization and allergy prevalence seemed to be associated with ragweed pollen pressure, such as quantity. The knowledge of the pollen count is relevant in clinical practice, mainly for the management of patients with allergy.

Respiratory allergy in immigrants to a highly industrialised area in Italy according to area of origin and time period

BACKGROUND

Migrants from developing to Western countries tend to become more sensitised to host than to origin country allergens, although substantial changes in migration patterns have occurred in recent decades.

METHODS

We investigated adult immigrants with respiratory allergy, first tested for allergic sensitisation between 1985 and 2012 in a highly industrialised area in Italy. A comparison was made of the sensitisation pattern between immigrants and a random sample of native-born subjects affected by a respiratory allergy, and among immigrants according to macro-region of origin and time period.

RESULTS

Between 1985 and 2012, 480 immigrants with respiratory allergy had a first positive allergy test. Immigrants were sensitised mainly to grass (67.1%), house dust mites (HDM) (38.5%) and birch (27.5%), with a pattern of sensitisation very similar to that observed in Italians (native-born). An increase in the proportion of subjects with asthma and of subjects with polysensitisation was observed from the first (1985-2002) to the middle (2003-2007) and the most recent period (2008-2012). In recent years, the proportion of subjects with polysensitisation in immigrants is higher than in Italians (native-born) (53.3% vs. 40.1%). Among immigrants, the risk of sensitisation to grass was higher in those from Sub-Saharan Africa (odds ratio, OR=2.76) and Latin America (OR=2.49), whereas risk of sensitisation to HDM was higher among immigrants from South Asia (OR=2.71), compared to immigrants from Eastern Europe.

CONCLUSIONS

Immigrants develop multiple sensitisations more frequently than native-born people, and are especially sensitised to local allergens; the country of origin seems to play a role.

Hypersensitivity to aeroallergens in patients with nasobronchial allergy

Background:

Aeroallergens are the most common causes of allergy.

Aim:

The aim of this study was to determine hypersensitivity to aeroallergens in patients with nasobronchial allergy.

Methods:

This retrospective population study included 2254 patients with nasobronchial allergy, from late adolescents to adults. Their response to aeroallergens was assessed by skin prick tests.

Results:

More patients had rhinitis (72.7%), than asthma (27.6%). Although majority of patients were female, allergy is more common in men than in women (p<0.05). Both groups of patients had the greatest number of positive skin prick tests for Dermatophagoides pteronyssinus (27.5%) and weed pollens (21.9%), followed by grass (18.3%) and tree pollens (10.1%). Ragweed is the most common positive weed pollen in both groups, more in patients with rhinitis (p=0.022). The cocksfoot is the most common grass pollen in rhinitis group (15.3%), but meadow grass (12.6%) in asthma patients. Birch is the most common tree allergen in the both groups.

Conclusions:

More patients with nasobronchial allergy have rhinitis than asthma. Skin prick tests are usually positive for Dermatophagoides pteronyssinus and weed pollens, followed by grass and tree pollens, and they are more common positive in patients with rhinitis than asthma.

Aeroallergen sensitization in childhood asthmatics in northern India

OBJECTIVE

To determine the prevalence of sensitization to common aeroallergens in asthmatic children and study the differences in characteristics of atopics and non atopics.

DESIGN

Analysis of data from a prospective cohort study.

SETTING

Pediatric Chest Clinic of tertiary care center in Northern India.

PATIENTS

Asthmatic children from 5-18 year of age.

MAIN OUTCOME MEASURES

Prevalence of sensitization to common aeroallergens.

RESULTS

Skin prick testing (SPT) was performed on 180 children above 5 years of age, with a mean (SD) age of 111.4 (34.2) months. 100 children (55.6%) were sensitized to at least one aeroallergen, suggesting atopy; 68 (37.8%) were sensitized to more than one allergen. 36.7% children were sensitized to housefly antigen; 31.1% to rice grain dust, 18.3% to cockroach, and 7.8% to house dust mite antigens. Atopic children had significantly higher median FENO during follow up than non-atopic children (17.5 ppb vs 13 ppb, P=0.002). There was a positive correlation between age and the number of allergens that an individual was sensitized to (r= 0.21; P=0.0049).

CONCLUSIONS

More than half of asthmatic children in our cohort had sensitization to one or more aeroallergens suggesting atopy; sensitization was most commonly seen to housefly antigen and rice grain dust. Atopic children had significantly higher FENO measurements during follow up as compared to non-atopic children.

Clinical significance of Alternaria alternata sensitization in patients with allergic rhinitis

PURPOSE

The aim of the study was to determine the epidemiologic profile of Alternaria alternata (AA)-sensitized patients with allergic rhinitis including coexistence of other atopic diseases, seasonal distribution of AA aeroallergens, age of onset of AA sensitization, and prevalence of sensitization to other allergens.

MATERIALS AND METHODS

History, clinical examination, and skin prick tests were performed in 623 patients with allergic rhinitis from central Greece. Patients' age, cosensitization, place of living, seasonal distribution, and concomitant symptoms were the variables used to discriminate between AA-sensitized and non-AA-sensitized patients. Significant predictor variables for AA sensitization were determined.

RESULTS

A alternata sensitization was associated with male sex, age younger than 18 years, living in new-built apartments in urban and semiurban areas by the sea, perennial distribution, and nonsmoking. A alternata-sensitized patients were affected more frequently by asthma than non-AA-sensitized patients. No significant differences were found in frequency of bronchitis, cough, conjunctivitis, urticaria, or eczema between patients sensitized or not to AA. Most (66.7%) of AA-sensitized patients were oligosensitized, 18.5% of patients were polysensitized, and 14.8% were monosensitized. Patients' age, cosensitization, place of living, and seasonal distribution were the significant predictor variables discriminating AA-sensitized from non-AA-sensitized patients. These variables correctly classified 79.7% of the patients. A alternata-sensitized patients were more frequently sensitized to grasses, cat epithelia, and flours-rye and less frequently sensitized to artemisia, Dermatophagoides pteronyssinus, D farinae, and chenopodium.

CONCLUSIONS

Patients meeting the aforementioned epidemiologic criteria should be preferentially offered skin prick tests for AA sensitization.

Factors associated with allergen sensitizations in patients with asthma and/or rhinitis in China

BACKGROUND

Allergen sensitization is influenced by genetic and environmental factors; however, the factors related to sensitizations in patients with rhinitis and asthma in China are largely unknown. This study investigated the factors associated with allergen sensitizations in patients with asthma and rhinitis in China.

METHODS

A cross-sectional survey was performed in 6304 patients with asthma and/or rhinitis from four regions of China. Patients completed a standardized questionnaire related to respiratory and allergic symptoms, family history of allergic diseases, smoking history, environmental exposure, and eating behaviors. They underwent skin-prick tests (SPTs) with 13 common aeroallergens. Blood samples were collected from 2268 of patients for specific IgE (sIgE) measurements against 16 common aeroallergens.

RESULTS

Patients with both asthma and rhinitis had higher prevalence of SPT and sIgE positivity to most allergens than those with asthma or rhinitis alone (p < 0.0001). Male gender, family history of allergic rhinitis, air-conditioner usage, sleeping on a mattress, and frequently eating meat were associated with increased risk of SPT and sIgE positivity. Using air-conditioner and sleeping on a mattress were further found to be associated with sIgE positivity to mites and molds. However, increased age and fish, fruit, and raw vegetable intake decreased the risk of SPT and sIgE positivity.

CONCLUSION

Family history of allergic rhinitis, male gender, using an air conditioner, sleeping on a mattress, and frequent meat consumption are risk factors for allergen sensitizations, whereas increased age and frequent fish, fruit, and raw vegetable consumption may protect patients with asthma and/or rhinitis from developing sensitizations in China.

Dolichandrone platycalyx: New entomophilous pollen--A report on pollen sensitization in allergic individuals

BACKGROUND

Dolichandrone platycalyx, commonly known as Nile trumpet tree, is believed to have originated in East Africa. However, this and the variants of this tree are found in Europe, Asia, and America (California and Florida). The tree mostly grows in tropical climates, but temperate species are also found. This study was designed to evaluate the allergenicity of D. platycalyx, one of the most common entomophilous avenue trees in Karnataka state, and to determine the pollen production of D. platycalyx.

METHODS

All of the patients with allergic rhinitis and asthma attending a tertiary care center in South India during August 2007 to March 2008 underwent a detailed clinical evaluation and skin-prick testing to common allergens along with D. platycalyx. Control subjects without any symptoms of respiratory allergy also underwent skin testing. The pollen counts were determined for a mature unopened flower of D. platycalyx.

RESULTS

A total of 317 subjects with respiratory allergy and 30 controls were included in the study. A significant percentage (16.1%) of patients evaluated were observed to be sensitive to Dolichandrone pollen extract by skin-prick testing, whereas none of the control subjects were found to be sensitized. D. platycalyx was the fourth most common sensitizer after Parthenium hysterophorus, Prosopis juliflora, and Artemesia vulgaris. D. platycalyx was found to be a moderate pollen producer at 66,000 pollens/flower.

CONCLUSION

Sensitization to D. platycalyx is common in subjects with respiratory allergies. The clinical relevance of this sensitization and other entomophilous plants needs additional study.