Occupational Allergy Research Articles

Occupational Allergic Airway Disease

The purpose of this paper was to review recent advances on causal agents, diagnosis and management of occupational allergic airway diseases. Food-derived products are a major cause of occupational asthma (OA) and occupational rhinitis (OR), and flour and seafood are the most important allergen sources. In recent years, farmers, cleaners, veterinarians, swimming pool workers and waste workers have been shown as novel categories at higher risk. Molecular diagnosis may greatly improve the diagnostic workup of allergic OA and OR. The use of immunotherapy and biologics may ameliorate the treatment of allergic OA. Occupational allergies are a burden for society and surveillance of exposed workers may identify new categories at risk. Cessation of exposure is the best treatment option for OA and OR. An accurate environmental control is needed to reduce asthma exacerbations in work-exacerbated asthma. The management of occupational allergic airway diseases should include a follow-up programme providing close collaboration between health care providers and patients, and ad hoc educational tools aimed at ameliorating patient’s knowledge should be developed.

Anaphylactic shock following castor bean contact: a case report

BackgroundThe castor bean plant, Ricinus communis, is known to have allergenic and toxic properties. Castor bean allergy has been described mainly as an occupational inhalation allergy in laboratory workers, in persons working in oil processing mills or in agricultural industry. So far, only one case of anaphylactic reaction due to castor bean sensitization confirmed by specific IgE has been described in literature.Case presentationA 30-year-old woman presented to the emergency room with severe angioedema followed by urticaria, hypotension and tachycardia. She recovered after treatment with antihistamines, corticosteroids, nebulized adrenaline and intravenous fluids. Food induced anaphylaxis was excluded by allergological investigations. After repeated thorough history, the patient mentioned having bitten into a castor bean just before the reaction. Cutaneous test (prick-to-prick) and specific IgE for castor bean were highly positive.ConclusionsWe report the second case of a severe anaphylactic reaction to castor beans, confirmed by IgE testing, reported in the literature. It underlines the importance of a meticulous history in allergology and highlights the fact, that castor beans may cause potentially fatal anaphylaxis.

Microbiological Biohazards Associated with Occupational Allergies

Microbiological occupational allergens usually originate from a part or products of bacteria, fungi, or arthropods. They may be harmful on their own or their impact may come from cross-reactions of their substance. It is mostly the respiratory system, conjunctiva, and skin that are affected. This short review clarifies the microbiological biohazards associated with occupational allergies.

Occupational contact allergy in bricklayers, tilesetters etc. - Current spectrum of sensitization and recent time trends.

Background: Occupational exposure of bricklayers, construction workers, tile setters etc. has changed during the last years. For some years now, all manually handled cement in the European Union and in Switzerland is chromate-reduced. Epoxy resin systems are being used in more and more fields of application. Improved worker’s protection, especially wearing protective gloves, is promoted. These changes influence the spectrum of occupational contact sensitization. Objective: Description of the current allergen spectrum in patients working in the building trade who suffer from occupational contact dermatitis. Material and methods: Retrospective analysis of data of the Information Network of Departments of Dermatology (IVDK), 2009 – 2011. Results: During the study period, 245 bricklayers, construction workers, tile setters etc. with occupational dermatitis have been patch tested. Potassium dichromate was the most frequent allergen, yielding 15.1% positive reactions, followed by epoxy resin with 13.7% positive reactions. Beyond that, there were 8 additional components of epoxy resin systems (5 reactive diluents and 3 amine hardeners), as well as 9 rubber ingredients, mainly thiurams, among the 30 most frequent allergens. In the course of time, a decline of chromate sensitization could be noted, paralleled by a decline of cobalt sensitization. In contrast, sensitization to epoxy resin has increased. Conclusion: Thanks to the usage of chromate-reduced cement, chromate sensitization continues to decline in the building trade. The increase of epoxy resin sensitization must prompt intensified prevention efforts. When recommending protective gloves, thiuram-free products should be preferred. The most important allergens are covered by the following test series recommended by the German Contact Dermatitis Research Group (DKG): DKG baseline series, DKG test series “building trade”, DKG rubber series.

United Airway Disease in Occupational Allergy

The term “united airway disease” has been used since 2000 to describe the strong association between asthma and rhinitis. Although this term is not extensively used, it refers to the fact that asthma and rhinitis are frequently associated and share common risk factors, causal agents and mechanisms. Similarly, since 2010 the term occupational united airway disease has been used to describe the strong association between occupational asthma and rhinitis. Rhinitis and occupational rhinitis are less severe diseases but more frequent than asthma and occupational asthma, respectively. Every year several case reports and epidemiological studies enhance the long list of agents responsible for occupational asthma and rhinitis with new agents or occupations. Primary, secondary and tertiary prevention strategies are aimed at reduction of the onset and severity of work-related respiratory diseases. Primary prevention mainly includes avoiding/reducing exposure to known sensitizing/irritant agents. Secondary prevention or early detection should focus on medical surveillance of individuals at risk, health and safety education and training of workers, and recognition of early bronchial/nasal symptoms. Tertiary prevention includes early recognition and diagnosis, appropriate removal from further exposure and pharmacologic treatment. Unfortunately, pharmacologic treatment has seldom been studied in occupational asthma and rhinitis, and it usually refers to the international guidelines of management of asthma and rhinitis aimed to achieve control of the two diseases. For simultaneous treatment of asthma and rhinitis, the anti-IgE monoclonal antibody omalizumab, effective in occupational asthma and rhinitis, is available. Immunotherapy has been shown to be effective in health care workers with occupational asthma due to natural rubber latex, in workers with occupational asthma due to laboratory animals and in baker’s asthma. A limitation of immunotherapy, however, can be systemic reactions after subcutaneous injections of sometimes non-standardized and non-purified extracts.

Association of household cleaning agents and disinfectants with asthma in young German adults

ObjectivesWe scrutinised the association of private use of household sprays and disinfectants with asthma incidence in young adults in the transition from school to working life.MethodsBetween 2007 and 2009,2051 young...

Component-Resolved and Complementary Tests in the Diagnosis of Occupational Allergy: Advantages and Limitations

Enhancing the repertoire of in vitro methods together with the development of recombinant technology in the field of allergy diagnosis brought tremendous advances in understanding allergens, allergic reactions, and patients’ care. This review is focusing not only on component-resolved diagnosis with occupational allergens, complementary methods, their advantages to improve the in vitro diagnosis for occupational allergy but also their limitations. Up to now, the number of occupational asthma sensitizers characterized on the molecular level and their availability for routine diagnosis is very low. One exception, however, is Hevea brasiliensis latex as an important occupational allergen source. H. brasiliensis latex is an excellent model for the useful application of recombinant single allergens for improvement of routine diagnostics. Despite the many efforts and excellent research in the field of baker’s asthma to characterize the occupationally relevant allergens the results are highly diverse. No major allergen can be identified and the IgE-sensitization profile of each baker showed great inter-individual variation. Therefore, for routine diagnosis of baker’s asthma, the assessment of allergen-specific IgE with the whole wheat (and/or rye) flour extract is still recommended. Unfortunately, no wheat allergens relevant for baker’s asthma are commercially available, although they might help to discriminate between wheat-induced food allergy, grass pollen allergy, and baker’s asthma. In particular cases with discrepancy between different diagnostic tests, the determination of basophil activation test is a recommended option. Flow cytometry determination of CD63 or CD203c on basophils induced by stimulation with the relevant allergen is a good clinically validated test and also useful for the diagnosis of occupational allergy. It is still necessary to increase the knowledge of occupational allergen molecules and include standardized tools into routine diagnostic. For the future, combination of new diagnostic tools and biomarkers, platforms, and complementary methods in occupational allergy and asthma diagnosis is a promising option. In addition, integration of these possibilities in workplace-related allergy and asthma studies is helpful to understand the complex interaction between work-related exposure, individual susceptibility and health outcome.

Infrequent Treatments for Occupational Asthma: Immunotherapy and Biological Therapy

Occupational asthma is an important social, health, and economic burden in our society, but its treatment options have not been yet sufficiently explored. Drug therapies do not differ much from ordinary asthma treatments, and avoidance is the main managing option for this condition. However, other therapeutic options like immunotherapy and biological therapies have not been used as in other asthma and rhinitis etiologies. Occupational asthma has different pathomechanisms depending of its triggers, but in immunological IgE-dependent asthma, these therapies can be fairly efficient. Not many immunotherapy studies have been carried out lately on this topic, and its reproducibility might be its biggest disadvantage. Maybe the main existing limitation is the lack of standardized extracts in order to perform this treatment. With no proper extracts, this treatment cannot be implemented, and its tolerance is going to differ depending on the extract used in each specific case. On the other hand, biological treatments are a promising option in the management of severe occupational asthma. Not many studies have been conducted so far in occupational allergy. Nevertheless, these biological treatments are upcoming and evolving therapies, so we expect further studies in a close future, including recently approved therapeutic options such as mepolizumab in eosinophilic refractory asthma. These new treatment possibilities should enhance their use and empower them also in the occupational field.

Occupational respiratory allergy in peach crop workers.

Occupational respiratory diseases in workers of peach tree crops have been reported punctually and have been associated with sensitization to proteins present in both pollen and leaf tree. We report the study of 37 workers with respiratory symptoms related to occupational exposure to peach trees. Prick tests and specific IgE determinations were performed with extracts from leaves and branches of peach tree. Immunodetection in leaf extract was realized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis SDS-PAGE-immunoblotting with patient sera and rabbit serum anti-Pru p 3. Immunodetection inhibition was performed with rPru p 3 and pollen profilins. The clinical relevance of sensitization was demonstrated by specific bronchial challenge test (SBCT) with peach leaf extract. Most patients suffered symptoms when peach trees had leaves, specifically during thinning and harvesting fruit (rhinoconjunctivitis: 100% and asthma: 67.5%). Sensitization to leaf extract was demonstrated in 86% of patients. IgE-immunoblotting with peach leaf extract revealed in six patient sera a pair of bands of 10 and 16 kDa, and in nine a 16-kDa band. Those bands could be two isoforms of peach leaf lipid transfer proteins( LTP), so the recognition frequency of some LTP isoform by our patient sera was 42%. 33% of the sera recognized a doubled band of about 14.5 kDa and this recognition was inhibited by nPho d 2. The SBCT with peach leaf extract was positive in the asthmatic sensitized patients tested. Sensitization to peach leaves was the cause of occupational respiratory symptoms in our patients. Some patient sera revealed IgE-binding proteins matching LTP and/or profilin.

Occupational Latex Allergy: the Current State of Affairs.

Allergy to natural rubber latex (NRL) reached epidemic proportions during the nineties and led to intense preventive efforts. The aim of this review was to provide a comprehensive compilation of the current status of occupational NRL allergy. Recent advances led to the characterization of 15 NRL allergens and the development of assays for measuring the allergen content of NRL materials and specific IgE antibodies against NRL allergen components. Preventive measures aimed at reducing workplace exposure to NRL allergens were associated with decreasing incidence rates of NRL allergy. However, a pooled analysis of epidemiological surveys published during the last 10years provided prevalence estimates of NRL sensitization and allergy similar to those derived from studies conducted before 2003. Substantial progress has been made in the understanding and prevention of NRL allergy, although the disease may still remain a worldwide cause of concern.

Diagnostic accuracy of specific IgE antibodies measurements in occupational airway allergy to high molecular weight agents

The performance of specific inhalation challenge test (SICT) - reference method in diagnostics of occupational allergy - has some limitations due to health status of a particular patient. Therefore, it is extremely important to identify usefulness of other tests, and the evaluation of diagnostic accuracy of commercially available serum specific immunoglobulin E (sIgE) kits to the most common high molecular weight agents has been launched. The study group comprised 141 subjects - 110 bakers and 31 farmers - with suspicion of occupational airway allergy. All patients underwent evaluation of serum sIgE to occupational allergens with the use of Phadia and Allergopharma kits: in bakers to flour mix and α-amylase, in farmers to epithelium of cow, pig and feathers. Specific inhalation challenge test with workplace allergens performed in all subjects was a reference method for further analysis. Serum specific IgE to flour mix had the highest sensitivity (Phadia - 95.6%, Allergopharma - 88.3%), while its specificity was relatively low (Phadia - 47.8%, Allergopharma - 25%). There were numerous discrepancies between the results of sIgE estimation for particular single allergens (k87, e4, e83), as well as for their mixtures (fx901, fx20, ex71), performed with the kits of both companies (Phadia vs. Allergopharma). Evaluation of serum specific IgE is characterized by inadequate sensitivity, specificity and predictive value to take the place of specific inhalation challenge test in diagnostics of occupational respiratory allergy. Med Pr 2017;68(1):31-43.

Chromium(VI) Contact Dermatitis: Getting Closer to Understanding the Underlying Mechanisms of Toxicity and Sensitization!

Various haptens trigger innate immune pathways and/or induce cytotoxicity as a part of sensitization. Adam etal. decipher invitro the mechanisms by which chromium(VI) induces inflammation, the likely prerequisites for toxicity, sensitization, and allergic contact dermatitis against chromium(VI). Importantly, and in line with other observations, chromium(VI), but not chromium(III) (or Ni(II)), induces mitochondrial reactive oxygen species accumulation. Mitochondrial reactive oxygen species in turn activate the NLRP3 inflammasome, allowing increased IL-1β processing and secretion, which likely underlies both chromium(VI)-induced cutaneous toxicity and sensitization. Interrupting this mechanism, perhaps with reducing agents or inhibitors of the NLRP3/IL-1 axis, may be a new option to prevent occupational chromium toxicity and allergy.

Occupational Allergy

An estimated 11 million workers in the USA are potentially exposed to agents that can become a cause of allergic diseases such as occupational asthma and allergic contact dermatitis, which can adversely affect health and well-being. Hundreds of chemicals (e.g. metals, epoxy and acrylic resins, rubber additives, and chemical intermediates) and proteins (e.g. natural rubber latex, plant proteins, mould, animal dander) present in virtually every industry have been identified as causes of allergic disease. In general, allergens can be classified as low molecular weight (chemical) allergens and high molecular weight (protein) allergens. These agents are capable of inducing immunological responses that are both immunoglobulin E and non-immunoglobulin E-mediated. Interestingly, the same chemical can induce diverse immune responses in different individuals. As new hazards continue to emerge, it is critical to understand the immunological mechanisms of occupational allergic disease. Specific understanding of these mechanisms has direct implications in hazard identification, hazard communication, and risk assessment. Such efforts will ultimately assist in the development of risk management strategies capable of controlling workplace exposures to allergens to prevent the induction of sensitisation in naïve individuals and inhibit elicitation of allergic responses. The purpose of this short review is to give a brief synopsis of the incidence, agents, mechanisms, and research needs related to occupational allergy.

Survey of Occupational Allergic Contact Dermatitis and Patch Test among Clothing Employees in Beijing.

Occupational population-based epidemiological data relating to occupational contact allergies in the Chinese clothing industry are limited. To investigate the prevalence of occupational allergic contact dermatitis (OACD) and to identify the causative allergens among clothing employees in China, a cross-sectional study was conducted in 529 clothing employees at 12 clothing factories in Beijing. All employees were subjected to an interview using self-administered questionnaire and skin examination, and those who were diagnosed with occupational contact dermatitis (OCD) were patch tested. In the present survey, we found that the overall 1-year prevalence of OACD among the clothing employees was 8.5%. The 1-year prevalence of OACD among workers (10.8%) was significantly higher than that among managers (3.2%). The lesions were primarily on the hands and wrists in workers, but the face and neck in managers. The major allergens were nickel sulfate and cobalt dichloride in workers and colophony and p-tert-butylphenol formaldehyde resin in managers. In conclusion, workers are at a higher risk of OACD compared with managers in the Chinese clothing industry. In addition to hand dermatitis in workers, airborne contact dermatitis on the face and neck should be also addressed in managers.

Airborne exposure to laboratory animal allergens

Exposure to laboratory animal allergens remains a significant cause of IgE-mediated occupational allergy and asthma. Since 2005, we have measured the major mouse and rat allergens (mus m 1 and rat n 1) collected on filters from air sampling in a range of UK and non-UK animal facilities. Supplied core data allowed us to construct an anonymized database of atmospheric results in ng m–3 containing 3080 mouse and 1392 rat analyses. Roughly twice as many static samples compared to personal samples had been sent for analysis. The medians (90th percentiles) for the mouse and rat allergens employing personal atmospheric sampling were 2.6 (60.6) and 0.4 (12.4) ng m–3 respectively; for static samples the equivalent values were 0.2 (3.7) and 0.1 (1.4) ng m–3. Where unequivocal sample descriptors were provided with samples, results were categorised to activities/areas. Medians and 90th percentiles in these categories suggest that staff undertaking cleaning out, dumping of soiled bedding and cleaning cages can still have very substantial potential exposures in some facilities. The move to filtered cages appears to reduce general exposure, but filter changing and/or cleaning can lead to high exposures. In some facilities, animal receipt can cause significant exposures, as well as activities such as bleeding, culling and dosing; all activities involving the handling of animals outside of cages. We believe that the data presented may help those using air measurements in such facilities to improve their control of exposure to such aeroallergens, and thus reduce the risk of both sensitisation and subsequent allergic health problems, including the development of allergic asthma.

Occupational allergy to food-derived allergens

Although most cases of food allergy are related to food ingestion, occupational exposure to foods by contact or inhalation may also lead to adverse reactions, inducing contact urticaria or dermatitis, asthma, rhinitis, hypersensitivity pneumonitis, and anaphylaxis. Almost 10–25% of cases of allergic occupational asthma and rhinitis are due to food products. Animal and vegetal high-molecular weight proteins derived from aerosolized foods during food processing or handling at the workplace, as well as additives used as preservatives and antioxidants, and food contaminants, are the main causal agents. Farmers who grow and harvest crops and workers employed in food processing, storage and packing, and those involved in food preparation and transport are considered at increased risk for developing food-induced occupational asthma and rhinitis. Bakers’ asthma is the most frequent type of occupational asthma all around the world. Seafood processing industry is also at higher risk for asthma and rhinitis. A proportion of cases of asthma and rhinitis in food industry is also related to latex gloves used during food processing. The diagnosis of food-related occupational asthma and rhinitis includes a careful clinical and occupational history, respiratory functional assessment and measurement of non-specific bronchial hyperresponsiveness, immunologic assessment and specific inhalation challenge. The management includes environmental interventions aimed to avoid or reduce exposure to the offending agent, pharmacologic therapy, and allergen immunotherapy when available. Only few cases of food-induced occupational anaphylaxis have been described. The management of these emergencies should follow the current guidelines on anaphylaxis. The worker should be educated in managing future possible episodes that may also occur out of the workplace, by instance after accidental ingestion of the culprit allergen, and to carry 2 pre-loaded adrenaline delivery systems and a MedicAlert bracelet.

Occupational allergic disease: socio-epidemiological aspects from a specialized outpatient clinic in the city of Sao Paulo, Brazil.

Occupational diseases involving the immune system are considered to be occupational allergic diseases (OAD); 15% of occupational diseases are allergic. The social consequences of OAD are significant for both workers and employers. To describe demographic and clinical characteristics of patients with OAD and their social outcomes. Descriptive and retrospective study of the medical records of patients diagnosed with OAD cared at the occupational allergy clinic of a university hospital in São Paulo, Brazil. A total of 72 patients exhibited OAD, with age 21 to 89 years old; 52% were male. Atopic antecedents were described for 35% of patients. Most patients worked in the chemical industry (17%), cleaning (15%), construction (11%) and health care (8%). Occupational rhinitis was found in 26% of the patients, work-related asthma in 18%, asthma and rhinitis in 25%, and allergic contact dermatitis in 13%. In regard to the social outcomes, 36 (50%) workers remained in their jobs, 19 (26%) changed function, 7 (10%) changed occupation, 7 (10%) were fired and 3 (4%) retired. In the present study, OAD prevailed among males and within the economically active age; cases of occupational rhinitis were the most frequent. Half of the employees remained in the same job position even after diagnosis.

Occupational allergy to fruit flies (Drosophila melanogaster) in laboratory workers

ObjectivesDrosophila melanogaster (the ‘fruit fly’) is commonly used in genetic research, but there is only one report of IgE-associated allergy in exposed workers. 4 newly identified cases prompted us to...

Patch testing with rubber series in Europe: a critical review and recommendation.

Rubber additives constitute an important group of contact allergens, particularly in certain occupations. To collect information regarding the current practice of using a 'rubber series' in Europe, and discuss this against the background of evidence concerning the prevalence of allergy in order to derive a recommendation for a 'European rubber series'. The following were performed: (i) a survey targeting all members of the COST action 'StanDerm' consortium, (ii) analysis of rubber contact allergy data in the database of the European Surveillance System on Contact Allergies, and (iii) a literature review. Information from 13 countries was available, from one or several departments of dermatology, and occasionally occupational health. Apart from some substances tested only in single departments, a broad overlap regarding important allergens was evident, but considerable variation existed between departments. An up-to-date 'European rubber series' is recommended, with the exclusion of substances only of historical concern. A 'supplementary rubber series' containing allergens of less proven importance, requiring further analysis, is recommended for departments specializing in occupational contact allergy. These should be continually updated as new evidence emerges.

Occupational Allergies: A Brief Review

Occupational allergies are groups of work-related disorders that are accompanied by immunologic reaction to workplace allergens and include occupational asthma, rhinitis, hypersensitivity pneumonitis, dermatitis, and anaphylaxis. This mini review presents a brief analysis of the more important aspects of occupational allergic disorders.