3-(Bromomethyl)-2-chloro-4-(methylsulfonyl)- benzoic acid: a new cause of sensitiser induced occupational asthma, rhinitis and urticaria

[New allergens for occupational dermatology?]

BACKGROUND

The environment is continuously subject to change. Exposures in the work environment and therefore the importance of occupational type I and type IV allergens may change.

OBJECTIVES

The most important trends concerning occupational allergens, new occupational allergens/allergen exposures, the diagnostic procedure to detect new allergens in practice and regulatory developments are presented.

MATERIALS AND METHODS

Building on known relevant allergen exposures in occupational dermatology, published trends from clinical cohorts are evaluated and a systematic literature search (PubMed 2016-2021) for new occupational allergens is also performed RESULTS: Occupations with the highest incidence of occupational allergic contact urticaria and/or protein contact dermatitis include bakers, farmers and farm workers, veterinary technicians, veterinarians, cooks, dairy and livestock workers, gardeners, and hairdressers. The highest risk of developing occupational contact dermatitis is in health care, agriculture, metalworking occupations and machine operators, the food sector, service industries, and construction occupations. The search strategy "new occupational allerg*" yielded 603 hits and "novel occupational allerg*" 158 hits. A total of 25 papers included results relevant to the research question and were processed. New protein-based immediate-type allergens, as well as contact allergens (haptens) relevant for occupational dermatology, are presented.

CONCLUSIONS

Current trends on known occupational allergens and new occupational allergens in the period 2016-2021 can be identified. Only a thorough individual workplace history and testing of patients' own materials can identify new allergens in occupational dermatology.

Occupational Exposure to Metals and Solvents: Allergy and Airway Diseases

PURPOSE OF REVIEW

Occupational allergic diseases (OAD) such as occupational contact dermatitis (OCD), occupational asthma (OA), and occupational rhinitis (OR) are the most prevalent occupational diseases in industrialized countries. The purpose of this review is to provide an update about the main occupational metal and solvent exposures related to allergy and airway diseases and to discuss newly defined causative agents and industries in this field.

RECENT FINDINGS

Currently for over 400 causative agents for OA and OCD, several hundreds of agents for OR have been identified. Although many studies have reported an overall decline in OAD related to known agents after implementation of efficient and effective workplace preventive measures, the constant development of new products continuously introduces to the market potential unknown respiratory hazards. Workplace allergens are often high molecular weight (HMW) agents that are > 10 kDa molecular weight and capable of eliciting IgE sensitization. Sensitizing low molecular weight (LMW) agents are often reactive chemicals. Metals and solvents are two large causative agent groups related to OADs that mainly behave as LMW (< 10 kDa) sensitizers and/or irritants. Avoidance of causative exposures through control strategies is the primary prevention approach for OADs. These strategies must be applied and covered for all known and newly defined causative agents. This review aims to summarize current status of known occupational metal and solvent exposures related to allergy and airway diseases and to discuss newly defined causative agents and industries in this field.

Measurement of bronchial hyperreactivity: comparison of three Nordic dosimetric methods

Clinical testing of bronchial hyperreactivity (BHR) provides valuable information in asthma diagnostics. Nevertheless, the test results depend to a great extent on the testing procedure: test substance, apparatus and protocol. In Nordic countries, three protocols predominate in the testing field: Per Malmberg, Nieminen and Sovijärvi methods. However, knowledge of their equivalence is limited. We aimed to find equivalent provocative doses (PD) to obtain similar bronchoconstrictive responses for the three protocols. We recruited 31 patients with suspected asthma and health care workers and performed BHR testing with methacholine according to Malmberg and Nieminen methods, and with histamine according to Sovijärvi. We obtained the individual response-dose slopes for each method and predicted equivalent PD values. Applying a mixed-model, we found significant differences in the mean (standard error of mean) response-dose (forced expiratory volume in one second (FEV₁)%/mg): Sovijärvi 7.2 (1.5), Nieminen 13.8 (4.2) and Malmberg 26 (7.3). We found that the earlier reported cut-point values for moderate BHR and marked BHR between the Sovijärvi (PD₁₅) and Nieminen (PD₂₀) methods were similar, but with the Malmberg method a significant bronchoconstrictive reaction was measured with lower PD₂₀ values. We obtained a relationship between slope values and PD (mg) between different methods, useful in epidemiological research and clinical practice.

Update on the Management of Occupational Asthma and Work-Exacerbated Asthma

Work-related asthma is the most common occupational lung disease encountered in clinical practice. In adult asthmatics, work-relatedness can account for 15%-33% of cases, but delays in diagnosis remain common and lead to worse outcomes. Accurate diagnosis of asthma is the first step to managing occupational asthma, which can be sensitizer-induced or irritant-induced asthma. While latency has traditionally been recognized as a hallmark of sensitizer-induced asthma and rapid-onset a defining feature of irritant-induced asthma (as in Reactive Airway Dysfunction Syndrome), there is epidemiological evidence for irritant-induced asthma with latency from chronic moderate exposure. Diagnostic testing while the patient is still in the workplace significantly improves sensitivity. While specific inhalational challenges remain the gold-standard for the diagnosis of occupational asthma, they are not available outside of specialized centers. Commonly available tests including bronchoprovocation challenges and peak flow monitoring are important tools for practicing clinicians. Management of sensitizer-induced occupational asthma is notable for the central importance of removal from the causative agent: ideally, removal of the culprit agent; but if not feasible, this may require changes in the work process or ultimately, removal of the worker from the workplace. While workers' compensation programs may reduce income loss, these are not universal and there can be significant socio-economic impact from work-related asthma. Primary prevention remains the preferred method of reducing the burden of occupational asthma, which may include modification to work processes, better worker education and substitution of sensitizing agents from the workplace with safer compounds.