Incidence and host determinants of work-related rhinoconjunctivitis in apprentice pastry-makers

Occupational Rhinitis

There is convincing evidence that tight relationships between the upper and lower airways also apply to the workplace context. Most patients with occupational asthma (OA) also suffer from occupational rhinitis (OR), although OR is 2 to 3 times more common than OA. OR most often precedes the development of OA, especially when high-molecular-weight protein agents are involved, and longitudinal cohort studies have confirmed that OR is associated with an increased risk for the development of OA. The level of exposure to sensitizing agents at the workplace is the most important determinant for the development of IgE-mediated sensitization and OR. Atopy is a risk factor for the development of IgE-mediated sensitization only to high-molecular-weight agents. In workers with work-related rhinitis symptoms, documentation of IgE-mediated sensitization to a workplace agent via skin prick testing or serum specific IgE confirms a diagnosis of probable OR, whereas specific nasal provocation testing in the laboratory remains the reference method to establish a definite diagnosis of OR. Complete avoidance of exposure to the causal agent is the most effective therapeutic option for controlling work-related nasal symptoms and preventing the development of OA. If complete elimination of exposure is expected to induce meaningful adverse socioeconomic consequences, reduction of exposure can be considered as an alternative approach, but it is important to consider the individual risk factors for the development of OA to implement a more personalized management of OR.

Specific work activities and exposure to respiratory hazards - predictors of lung function impairment among crop farmers

OBJECTIVE: The objective of the study was to evaluate the specific work activities and occupational exposure to respiratory hazards as predictors of chronic respiratory symptoms development, lung function decline, and respiratory health impairment among crop farmers. METHODS: A cross-sectional survey was performed, including 87 crop farmers (mean age: 53.4 ± 7.8 years; and mean exposure duration: 22.9 ± 7.8 years) and 80 office workers as a control group (mean age: 52.7 ± 8.2 years) matched for age, smoking habits, and socioeconomic status. Subjects were evaluated by a questionnaire on respiratory symptoms in the past 12 months and spirometry testing. RESULTS: Crop farmers had a significantly higher prevalence of cough (41.4), phlegm (28.7%), and dyspnea (21.8%), than controls (p < 0.05). All mean baseline spirometric parameters were lower in crop farmers, but statistical significance was confirmed only for MEF25, MEF50, and MEF75 (p = 0.003, p = 0.000, and p = 0.001, respectively). Most of the respiratory symptoms were significantly associated with common work activities of crop farmers and all-day exposure to certain respiratory hazards. Age, exposure duration, and their combined effect with smoking habit had a significant effect on forced expiratory volume in one second FEV1 and FEV1/forced vital capacity. CONCLUSION: The results confirm that occupational exposure among crop farmers is associated with higher prevalence of respiratory symptoms and lung function decline and, together with specific workflow activities, may not only be a predictors of respiratory health impairment, but also a key tool in the creation of preventive strategies.

ICON: Diagnosis and management of allergic conjunctivitis

Ocular allergy (OA), interchangeably known as allergic conjunctivitis, is a common immunological hypersensitivity disorder affecting up to 40% of the population. Ocular allergy has been increasing in frequency, with symptoms of itching, redness, and swelling that significantly impacts an individual's quality of life (QOL). Ocular allergy is an often underdiagnosed and undertreated health problem, because only 10% of patients with OA symptoms seek medical attention, whereas most patients manage with over-the-counter medications and complementary nonpharmacological remedies. The clinical course, duration, severity, and co-morbidities are varied and depend, in part, on the specific ocular tissues that are affected and on immunologic mechanism(s) involved, both local and systemic. It is frequently associated with allergic rhinitis (commonly recognized as allergic rhino conjunctivitis), and with other allergic comorbidities. The predominance of self-management increases the risk of suboptimal therapy that leads to recurrent exacerbations and the potential for development of more chronic conditions that can lead to corneal complications and interference with the visual axis. Multiple, often co-existing causes are seen, and a broad differential diagnosis for OA, increasing the difficulty of arriving at the correct diagnosis(es). Ocular allergy commonly overlaps with other anterior ocular disease disorders, including infectious disorders and dry eye syndromes. Therefore, successful management includes overcoming the challenges of underdiagnosis and even misdiagnosis by a better understanding of the subtleties of an in-depth patient history, ophthalmologic examination techniques, and diagnostic procedures, which are of paramount importance in making an accurate diagnosis of OA. Appropriate cross-referral between specialists (allergists and eyecare specialists) would maximize patient care and outcomes. This would significantly improve OA management and overcome the unmet needs in global health.

Occupational rhinitis and occupational asthma: Association or progression?

BACKGROUND

Occupational asthma is the most frequently reported occupational respiratory disease in registries, and is often co-diagnosed with occupational rhinitis. We undertook a systematic review of the English-language epidemiologic literature linking these two conditions, with emphasis on progression from occupational rhinitis to occupational asthma.

METHODS

PubMed and Embase were queried in a series of structured searches designed to identify studies comparing occupational asthma and occupational rhinitis incidence or prevalence in occupationally exposed individuals.

RESULTS

The searches yielded a total of 109 unique citations, 15 of which yielded inferential data on the occupational rhinitis-asthma relationship. Nine of fifteen studies showed statistically significant associations between the occurrence of occupational rhinitis and occupational asthma among individual workers.

CONCLUSIONS

Limited data support the notion that occupational rhinitis precedes the development of occupational asthma, particularly when high-molecular-weight (HMW) agents are involved. The relationship between the two conditions could not be evaluated in many relevant studies due to a lack of cross-tabulation of individual cases.

Prevalence of allergic rhinitis based on the SACRA questionnaire among Japanese nursing professionals with asthma

Although adult asthma is attributable to occupational factors and asthma and rhinitis are related, relatively few studies have investigated the prevalence of occupational rhinitis based on occupation, and knowledge of occupational rhinitis in Japan is currently limited. The objective of this cross-sectional study was to estimate the prevalence of allergic rhinitis among Japanese nursing professionals with asthma. A postal survey was conducted from October to December 2013 using translated versions of the European Community Respiratory Health Survey for the prevalence of asthma and State of the Impact of Allergic Rhinitis on Asthma Control questionnaire for the prevalence of rhinitis. Of 4,634 Japanese nursing professionals, 497 subjects had asthma, and 270 of these 497 subjects had allergic rhinitis (54.3%; 95% confidence interval [CI], 49.7-58.7). Latex allergy was significantly associated with allergic rhinitis (odds ratio, 1.77; 95% CI, 1.21-2.60). There was no relationship between employment period and prevalent allergic rhinitis. The results of this study provide fundamental information regarding occupational health among Japanese nursing professionals, including the prevalence of allergic rhinitis among Japanese nursing professionals with asthma and latex allergy as a potential risk factor for prevalent allergic rhinitis.

Career Advice for Young Allergy Patients

BACKGROUND

One-third of all young persons entering the work force have a history of atopic disease. Occupationally induced allergy and asthma generally arise in the first few months on the job, while pre-existing symptoms tend to worsen. Young persons with a history of an atopic disease should receive evidence-based advice before choosing a career.

METHODS

We systematically searched PubMed for cohort studies investigating the new onset of asthma, rhinitis, or hand eczema among job trainees from before the start of training and onward into the first few years on the job. The search revealed 514 articles; we read their abstracts and selected 85 full-text articles for further analysis. 24 of these met the inclusion criteria.

RESULTS

According to present evidence, atopy and a history of allergic disease (allergic rhinitis, atopic dermatitis) are the main risk factors for occupationally induced disease. The predictive value of a personal history of allergic diseases for the later development of an occupationally induced disease varies from 9% to 64% in the studies we analyzed. It follows that only young people with severe asthma or severe atopic eczema should be advised against choosing a job that is associated with a high risk of allergy, e.g., hairdressing or working with laboratory animals. Young people with a history of other atopic diseases should be counseled about their individual risk profile.

CONCLUSION

In view of the relatively poor predictive value of pre-existing atopic disease, secondary prevention is particularly important. This includes frequent medical follow-up of the course of symptoms over the first few years on the job. If sensitization or allergic symptoms arise, it should be carefully considered whether exposure reduction will enable the apprentice to stay on the job.

[Occupational rhinitis and allergic conjunctivitis]

Occupational rhinitis is an inflammatory disease of the nose, which is characterised by intermittent or persistent symptoms, arising from causes and conditions attributable to a particular work environment and not from stimuli encountered outside the workplace. Its clinical symptoms such as nasal congestion, sneezing, rhinorrhoea, itching, nasal airflow limitation are very similar to the symptoms of allergic rhinitis caused by other (classical) agents. Occupational allergic conjunctivitis is an IgE mediated disease, provoked by a substance in the air of the workplace. Its clinical signs (itching, tearing, conjunctival hyperaemia and oedema and, in some cases when the cornea is also involved, blurred vision, photosensitivity) are similar to other forms of allergic conjunctivitis. Risk factors (which in most of the cases occur in both diseases) include history of atopy, high concentration of the irritant agent and multiple irritant agents in the air of the workplace. Atopy has been associated with an increased risk of specific sensitisation to a variety of high molecular weight agents. For the diagnosis of occupational rhinitis and occupational allergic conjunctivitis objective investigations such as allergen specific provocations are necessary in addition to clinical and occupational history. Management of these occupational diseases needs environmental interventions (increasing ventilation, decreasing the time of exposure, substitution of the irritant agent). Medical treatment of occupational rhinitis is very similar to other allergic diseases: oral antihistamines, local (nasal) corticosteroids, combined (antihistamine plus membrane stabilizer) eyedrops. The most important step in medical treatment of occupational allergic conjunctivitis is the daily application of combined eyedrops (for example: olopatadine). Orv. Hetil., 2014, 155(5), 170-175.

Genetic predictors of inflammation in the risk of occupational asthma in young apprentices

BACKGROUND

The influence of genetic predictors of inflammation and atopy on occupational asthma in apprentices is not known.

OBJECTIVES

To assess the influence of genetic polymorphisms of IL4RA, IL13, TNFA, IL1A, and IL5 on the decline of lung function and bronchial hyperresponsiveness in a prospective follow-up study of baker/pastry maker and hairdresser apprentices.

METHODS

A total of 351 apprentices were included in the study. We performed skin testing, spirometry, fractional exhaled nitric oxide measurement, and methacholine hyperreactivity testing at the initial visit and during and at the end of the 18-month training period. Gene variants of IL4RA, IL13, TNFA, IL1A, and IL5 were determined in DNA from nasal lavage.

RESULTS

IL13 R130Q/IL4RA S478P or IL13 R130Q//IL4RA Q551R were significant predictors of the decrease of forced expiratory volume and forced vital capacity (P ≤ .006). Genotype GG of TNFAG308A was associated with bronchial hyperresponsiveness in the whole population and in nonatopic individuals (90.63% vs 9.38%; odds ratio, 3.78; 95% confidence interval, 1.10-12.83). TNFA GA and IL5 CC and TNFA GA and IL1A CC were 2 epistatic predictors of exhaled nitrogen monoxide decrease during follow-up (P = .02 and P = .004, respectively). The association with TNFA GA and IL1A CC was the most significant in nonatopic bakers (P < .001).

CONCLUSION

We evidenced a predicting influence of IL13/IL4RA and TNFA in the early exposure to allergens and irritants that precedes occupational asthma. The significance of the associations in the absence of atopy suggests an influence of the genetics predictors related to inflammatory pathways.

Occupational rhinitis caused by concurrent sensitization to two different allergens

BACKGROUND

Exposure to wheat flour and guar gum is a well-known cause of occupational respiratory allergies among workers in the food processing industry. To date, there have been no reports of occupational rhinitis (OR) caused concurrently by two different allergens present in the workplace.

AIMS

To report a case of OR likely to be induced concurrently by exposure to wheat flour and guar gum in a mid-40s male employed in the food processing industry.

METHODS

Allergy tests and nasal challenge tests were performed to investigate and confirm the diagnosis of OR. We discuss potential mechanisms involved in the observed dual sensitization.

RESULTS

The patient showed positive responses to wheat and guar gum extracts on skin prick testing. The total IgE was 1680 kU/l (0-100 kU/l). The diagnosis of OR was confirmed by nasal challenge tests with wheat flour and guar gum on different days. In contrast to the control day, the challenge with flour and guar gum induced an immediate clinical reaction associated with a decrease in nasal volume measured by acoustic rhinometry. The patient was advised to avoid exposure to wheat and guar gum, which resulted in a gradual resolution of nasal symptoms.

CONCLUSIONS

Co-sensitization and cross-reactivity are possible mechanisms involved in cases of concurrent sensitization to related and unrelated allergens in patients complaining of work-related rhinitis symptoms.

Occupational rhinitis

Work-related rhinitis, which includes work-exacerbated rhinitis and occupational rhinoconjunctivitis (OR), is two to three times more common than occupational asthma. High molecular weight proteins and low molecular weight chemicals have been implicated as causes of OR. The diagnosis of work-related rhinitis is established based on occupational history and documentation of immunoglobulin E (IgE) mediated sensitization to the causative agent if possible. Management of work-related rhinitis is similar to that of other causes of rhinitis and includes elimination or reduction of exposure to causative agents combined with pharmacotherapy. If allergens are commercially available, allergen immunotherapy can be considered.

Impact of worker education on respiratory symptoms and sensitization in bakeries

BACKGROUND

Flour exposure is known to cause significant respiratory problems.

AIMS

To investigate the development of work-related sensitization, the period between first exposure and the development of symptoms (latent period) and the impact of workplace training programmes on respiratory health in plant bakers.

METHODS

Two hundred and sixty-four bakers were investigated by assessing work-related respiratory symptoms and latent period before symptoms/sensitization, spirometry and testing for an array of workplace-specific IgE.

RESULTS

There was a significant relationship between the presence of work-related respiratory symptoms and flour dust allergen-specific IgE. Latent periods varied widely: median for work-related nasal symptoms 36 months, cough 42 months and chest tightness 120 months. Latent periods were shorter for workers with evidence of flour sensitization (work-related wheeze: mean 13 months with sensitization, 97 months without, P < 0.05, work-related nasal symptoms, respectively; mean 19 months, 71 months, P < 0.01). Those warned of the health implications of flour dust had less work-related wheeze (warned; 1%, not warned 11%, P < 0.05). There was an excess of work-related symptoms and work-related-specific IgE combined in those who had not been warned of these health implications (12 versus 1%, P <0.01).

CONCLUSIONS

Reporting of 'being warned' of potential health implications from breathing flour dust protected strongly against the reporting of important health end points. Latent periods for the development of work-related symptoms varied widely. Simple health messages, which may be overlooked in worker training programmes, can have significant benefits for worker health in the bakery population.

EAACI position paper: prevention of work-related respiratory allergies among pre-apprentices or apprentices and young workers

Apprenticeship is a period of increased risk of developing work-related respiratory allergic diseases. There is a need for documents to provide appropriate professional advice to young adults aiming to reduce unsuitable job choices and prevent impairment from their careers. The present document is the result of a consensus reached by a panel of experts from European and non-European countries addressed to allergologists, pneumologists, occupational physicians, primary care physicians, and other specialists interested in this field, which aims to reduce work-related respiratory allergies (rhinoconjunctivitis and asthma) among allergic or nonallergic apprentices and other young adults entering the workforce. The main objective of the document is to issue consensus suggestions for good clinical practice based on existing scientific evidence and the expertise of a panel of physicians.

Allergic asthma after flour inhalation in subjects without occupational exposure to flours: an experimental pilot study

OBJECTIVE

Cross-reactivity between grass pollen and grain flour allergens is well known, but their significance in apprentice bakers with primary sensitization to grass pollen is not known.

METHODS

Twenty-five subjects with mild asthma (most of them with hay fever), but without prior occupational flour exposure, underwent standardized experimental inhalation challenges with placebo and wheat and rye flours in randomized order on three consecutive days. Sensitization to flours and environmental allergens was assessed by skin prick tests and specific IgE antibodies in sera. IgE inhibition experiments were performed with wheat and rye flours as solid phases, and grass and tree pollen as inhibitors.

RESULTS

Five subjects experienced a positive reaction after flour inhalation (responders), whereas 20 subjects did not show such a reaction (non-responders). All responders showed sensitizations to flours, whereas only 25% of the non-responders demonstrated the same sensitization. Specific IgE concentrations to flours, but also to grass and tree pollen, were higher in responders. Inhibition experiments demonstrated cross-reactivity between flours and grass or tree pollen, with higher inhibition rates in responders.

CONCLUSIONS

Subjects with pronounced sensitizations to grass or tree pollen, but without prior occupational exposure to flours, may experience both sensitization and allergic asthmatic reactions to flours due to cross-reactive grass and tree pollen allergens.

Occupational rhinitis

Work-related rhinitis, which includes work-exacerbated rhinitis and occupational rhinitis, may be two to three times more common than occupational asthma. Both high molecular weight proteins and low molecular weight chemicals have been implicated as causes of occupational rhinitis. A diagnosis is established based on occupational history and, if appropriate, documentation of IgE-mediated sensitization to the causative agent. Management of work-related rhinitis is similar to that of non-work-related rhinitis and includes elimination or reduction of exposure to offending agents combined with pharmacotherapy. If treatment allergens are commercially available, allergen immunotherapy may also be considered if appropriate.

Associations of airway inflammation and responsiveness markers in non asthmatic subjects at start of apprenticeship

Background

Bronchial Hyperresponsiveness (BHR) is considered a hallmark of asthma. Other methods are helpful in epidemiological respiratory health studies including Fractional Exhaled Nitric Oxide (FENO) and Eosinophils Percentage (EP) in nasal lavage fluid measuring markers for airway inflammation along with the Forced Oscillatory Technique measuring Airway resistance (AR). Can their outcomes discriminate profiles of respiratory health in healthy subjects starting apprenticeship in occupations with a risk of asthma?

Methods

Rhinoconjunctivitis, asthma-like symptoms, FEV1 and AR post-Methacholine Bronchial Challenge (MBC) test results, FENO measurements and EP were all investigated in apprentice bakers, pastry-makers and hairdressers not suffering from asthma. Multiple Correspondence Analysis (MCA) was simultaneously conducted in relation to these groups and this generated a synthetic partition (EI). Associations between groups of subjects based on BHR and EI respectively, as well as risk factors, symptoms and investigations were also assessed.

Results

Among the 441 apprentice subjects, 45 (10%) declared rhinoconjunctivitis-like symptoms, 18 (4%) declared asthma-like symptoms and 26 (6%) suffered from BHR. The mean increase in AR post-MBC test was 21% (sd = 20.8%). The median of FENO values was 12.6 ppb (2.6-132 range). Twenty-six subjects (6.7%) had EP exceeding 14%. BHR was associated with atopy (p < 0.01) and highest FENO values (p = 0.09). EI identified 39 subjects with eosinophilic inflammation (highest values of FENO and eosinophils), which was associated with BHR and atopy.

Conclusions

Are any of the identified markers predictive of increased inflammatory responsiveness or of development of symptoms caused by occupational exposures? Analysis of population follow-up will attempt to answer this question.

Exposure to respirable dust and crystalline silica in bricklaying education at Dutch vocational training centers

BACKGROUND

Construction workers are educated at vocational training centers before they begin their working lives. Future bricklayers and their instructors are exposed to respirable dust and possibly to hazardous respirable crystalline silica from trial mortar.

METHODS

Thirty-six personal air samples were collected at six training centers to estimate exposure to respirable dust for both students and teachers. A selection of 22 samples was analyzed for crystalline silica.

RESULTS

Average respirable dust exposures ranged from 0.59 mg/m(3) for teachers to 1.45 mg/m(3) for students performing recycling and cleaning tasks. In 45% of the analyzed samples, respirable crystalline silica was detected. Exposure to silica remained below the Dutch OEL (75 microg/m(3)). Exposure was significantly less for teachers than for students. This effect was found in both types of vocational training centers present in the Netherlands. Dry sweeping, as performed at all locations in this study, contributed considerably to the exposure to respirable dust. A first step in reducing exposure to dust and silica at training centers would therefore be to avoid dry sweeping. The presence of a dust extraction system, although not optimally designed, also significantly lowered exposure.

CONCLUSIONS

To assess a construction worker's lifetime exposure to respirable dust and crystalline silica, the vocational training period should also be taken into account. Several epidemiological studies have shown that time since first exposure can be an important risk factor for chronic health effects.

Thaumatin-like protein and baker's respiratory allergy

BACKGROUND

Baker's asthma and rhinitis are among the most common occupational diseases. Inhaled cereal flours, such as wheat, especially cause this disease.

OBJECTIVE

To identify and test in vivo clinically important wheat allergens in baker's respiratory allergy in a Finnish population.

METHODS

Potential wheat allergens were purified using chromatographic methods from salt-soluble protein extracts of wheat flour and were used in skin prick tests with serial 10-fold dilutions (0.5-0.005 mg/mL). Twenty patients with baker's rhinitis, asthma, or both participated in this study. All the patients had positive skin prick test reactions and specific IgE antibodies to wheat flour. The control group consisted of 10 healthy individuals. Molecular identities of purified wheat allergens were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and tandem mass spectrometry.

RESULTS

Allergen concentrations of 0.3-0.5 mg/mL revealed that 12 patients reacted to a-amylase inhibitor (alpha-AI), 9 to peroxidase I (PI), 9 to thaumatin-like protein (TLP), and 6 to lipid transfer protein 2G (LTP2G). Conversely, with allergen concentrations of 0.05 mg/mL, 5 patients responded to alpha-AI, 3 to PI, 4 to LTP2G, and 6 to TLP. Of these, TLP and LTP2G are now observed to be new allergens associated with baker's asthma.

CONCLUSIONS

In addition to the earlier-described alpha-AI and PI, TLP and LTP2G are important in vivo wheat allergens in baker's allergies in Finland. Further studies are needed to elucidate the role of these novel wheat allergens in respiratory disorders.

[Rhinitis and asthma related to cotton dust exposure in apprentices in the clothing industry]

OBJECTIVE

Respiratory allergies are the most common occupational diseases in the world. The aim of this study was to determine the prevalence of rhinitis and asthma among apprentices exposed to cotton dust in the clothing industry and to describe their epidemiologic and clinical profiles.

SUBJECTS AND METHODS

We carried out a descriptive study of 600 apprentices in a textile and clothing vocational training centre in the Monastir area. The investigation comprised a questionnaire exploring risk factors and symptoms appearing during their training. Subjects who developed allergic respiratory symptoms at the work-place underwent a clinical examination, rhinomanometry and investigation of their allergic status and respiratory function.

RESULTS

One hundred twenty apprentices (20%) developed allergic respiratory reactions due to exposure to textile dust (exclusively cotton) during their training, with a positive withdrawal-re-exposure test. Conjunctivitis (14.3%) and rhinitis (8.5%) were the most frequent allergic symptoms. Twenty eight apprentices (4.6%) presented symptoms of asthma. Rhinitis was associated with asthma in 45% of cases. Two cases of asthma were diagnosed clinically at the work-place following their exposure to textile dust. The prick test performed in 120 symptomatic apprentices was positive in 41.6% of cases. There was sensitization to pollens in 29 cases and to dermatophagoides in 13 cases. Cotton and wool allergy was noted in two cases. Allergic symptoms developing during the training were significantly more frequent in the atopic group, and they varied according to the intensity of textile dust exposure.

CONCLUSION

In the textile and clothing industry the frequency of respiratory disorders caused by allergens remains high, especially in atopic apprentices who constitute a population at high risk.

EAACI position paper on occupational rhinitis

The present document is the result of a consensus reached by a panel of experts from European and non-European countries on Occupational Rhinitis (OR), a disease of emerging relevance which has received little attention in comparison to occupational asthma. The document covers the main items of OR including epidemiology, diagnosis, management, socio-economic impact, preventive strategies and medicolegal issues. An operational definition and classification of OR tailored on that of occupational asthma, as well as a diagnostic algorithm based on steps allowing for different levels of diagnostic evidence are proposed. The needs for future research are pointed out. Key messages are issued for each item.

Agents causing occupational asthma

The workplace is a significant contributor to the burden of asthma. Although the majority of cases probably represent what is labeled work-exacerbated asthma, in a significant number of subjects, asthma is actually caused by 1 or more agents present in the workplace; this is occupational asthma. Two types of occupational asthma are distinguished, according to whether the asthma appears after a latency period. This article discusses (1) two types of agents causing asthma with a latency period and acting through an apparently immunologic mechanism (high-molecular-weight agents and low-molecular-weight agents) and (2) agents causing asthma without a latency period.

Occupational exposures and adult asthma

Occupational exposures can cause a new onset of asthma in a subset of susceptible workers on the basis of sensitization to a specific work agent or a high-level irritant exposure. Epidemiologic studies give insight into the natural history of occupational asthma, including host factors and environmental factors leading to the development of occupational asthma, the progression, and the potential role of preventive measures. Work-exacerbated asthma has been a focus of studies only recently but is recognized as common among asthmatic workers and is a potential cause of significant morbidity and socioeconomic impact.

Occupational rhinitis

The present document is the result of a consensus reached by a panel of experts from European and nonEuropean countries on Occupational Rhinitis (OR), a disease of emerging relevance, which has received little attention in comparison to occupational asthma. The document covers the main items of OR including epidemiology, diagnosis, management, socio-economic impact, preventive strategies and medicolegal issues. An operational definition and classification of OR tailored to that of occupational asthma, as well as a diagnostic algorithm based on steps allowing different levels of diagnostic evidence, are proposed. The needs for future research are pointed out. Key messages are issued for each item.

Long-term outcomes in a prospective cohort of apprentices exposed to high-molecular-weight agents

RATIONALE

We conducted a long-term (8-yr) follow-up of 408 apprentices entering programs involving exposure to high-molecular-weight allergens.

OBJECTIVES

The objectives were to assess the frequency of new and persisting sensitization, symptoms, and bronchial hyperresponsiveness in relation with job history after ending apprenticeship and to examine characteristics significantly associated with the incidence and remission of these occupational outcomes.

METHODS

A respiratory symptom questionnaire, skin prick tests with work-related allergens (laboratory animals, flour, and latex), spirometry, and methacholine challenge were administered. The association between incidence or remission of these outcomes and individual characteristics at baseline and end of apprenticeship was examined.

MEASUREMENTS AND MAIN RESULTS

In subjects who at any time during follow-up held a job related to their training (78%), the incidence of sensitization, rhinoconjunctival and chest symptoms, and bronchial hyperresponsiveness at follow-up was 1.3, 1.7, 0.7, and 2.0 per 100 person-years, respectively. The remission of these outcomes acquired during apprenticeship was 18.5, 9.6, 9.6, and 12.4 per 100 person-years, respectively, in subjects no longer in a job related to training. Several clinical, immunological, and functional characteristics at baseline and acquired during apprenticeship were found to be significantly associated with the incidence and remission of the outcomes.

CONCLUSIONS

The incidence of sensitization, symptoms, and bronchial hyperresponsiveness was lower while at work than during the apprenticeship period. A high proportion of subjects in a job not related to training experienced remission of symptoms acquired during apprenticeship.

Prevalence of work-related symptoms and serum-specific antibodies to wheat flour in exposed workers in the bakery industry

BACKGROUND

Although baker's asthma (BA) is a common occupational asthma, there have been few reports on this disease in Korean subjects.

OBJECTIVES

We evaluated the prevalence of serum-specific IgE, IgG1, and IgG4 antibodies in relation to work-related respiratory symptoms in a single industrial bakery.

METHODS

Three hundred and ninety-two bakery workers were administered and taken a questionnaire regarding respiratory symptoms. For symptomatic workers, the methacholine bronchial challenge test and specific bronchoprovocation tests with wheat extracts were carried out. Skin prick tests were performed and serum-specific IgE, IgG1, and IgG4 antibodies to wheat flour were detected. The IgE- and IgG4-binding components were identified by immunoblotting.

RESULTS

Sixty-seven workers (17.1%) complained of work-related upper and lower respiratory symptoms. The prevalence of BA based on positive bronchoprovocation test results was 1.5%. The sensitization rate to wheat flour was 5.9% by skin prick test and 6.5% by ELISA, and was closely associated with the presence of atopy and work-related lower respiratory symptoms (P<0.001 for both). IgE immunoblotting revealed six major IgE-binding components (27, 31, 36, 43, 54, and 72 kDa). The presence of wheat-specific IgG1 and IgG4 antibodies was found to be significantly associated with exposure intensity (P<0.05 for both).

CONCLUSIONS

The overall prevalence of wheat sensitization in a Korean bakery was 5.9%. We confirmed that an IgE-mediated response is the major pathogenic mechanism for the induction of work-related symptoms in wheat-exposed workers. Wheat-specific IgG antibodies may represent current or previous exposure to wheat dust.

[Occupational rhinitis]

INTRODUCTION

Rhinitis is one of the most common occupational diseases. It is often neglected by those affected because it causes little disability. It is poorly understood by doctors who have insufficient experience of occupational diseases and their causes. However it is often the first manifestation of a respiratory disorder that may cause physical complications and socio-economic disability.

BACKGROUND

Numerous diverse agents are potential causes of rhinitis. The diagnosis of occupational rhinitis should be considered when sneezing, rhinorrhoea or nasal obstruction are associated with work. The causal agent can be identified by ta-king a careful history. When the mechanism of the disease is immunologic the suspected antigen can be confirmed by skin testing, specific IgE or nasal provocation. The respiratory disorder of which rhinitis is the first manifestation may progress to asthma if the exposure continues. The prevention of occupational rhinitis depends on the reduction of exposure to allergens and/or irritants. When it has developed removal of the causative agent is essential to prevent progression to asthma.

Sensitization to Empynase(pronase B) in exposed hospital personnel and identification of the Empynase allergen

BACKGROUND

Empynase is a proteolytic enzyme that is widely used as an anti-inflammatory drug in Korea. We evaluated the prevalence of sensitization to Empynase in association with respiratory allergy symptoms in exposed hospital personnel, and identified the IgE-binding components in the Empynase extract, using sera with high levels of specific IgE antibodies.

METHODS

A total of 154 hospital personnel (135 nurses and 19 pharmacists) who worked in a university hospital and 123 unexposed healthy control subjects were enrolled. A questionnaire was administered that addressed demographics, job category, history of atopic diseases, diverse symptoms including nasal and lower respiratory symptoms, and the association of symptoms with work. Skin prick tests (SPTs) to common aeroallergens and Empynase extract were performed. Empynase-specific IgE antibody was detected by ELISA, and ELISA inhibition tests were conducted. IgE-binding components were identified by SDS-PAGE and IgE immunoblotting.

RESULTS

Forty-two subjects (27.3%) complained of work-related respiratory symptoms (WRRS). Five nurses (3.7%) and one pharmacist (5.3%) had work-related asthma symptoms, and 34 nurses (25.2%) and six pharmacists (31.6%) had work-related rhinitis symptoms. The prevalence of sensitization to Empynase on SPTs was 20.1%, and tended to be higher in pharmacists (31.6%) than in nurses (18.5%). It was estimated that 3.9-8.4% of hospital personnel had WRRS attributable to Empynase. The duration of exposure was longer in positive SPT responders than in negative responders (51.9+/-27.5 vs. 39.2+/-27.3 months, respectively; P<0.05), and the prevalence of Empynase-positive SPTs was significantly higher in subjects with asthma than in those without asthma (57.1% vs. 18.4%, respectively; P<0.05). The levels of Empynase-specific IgE antibodies were significantly higher in pharmacists (76.1+/-83.4 OD units) and nurses (56.3+/-103.0 OD units) than in normal controls (39.8+/-12.7 OD units; P<0.05). Seven subjects (two pharmacists and five nurses) had high serum levels of Empynase-specific IgE antibodies; six of these subjects had WRRS. ELISA inhibition tests were performed with the sera of these six subjects, revealing significant inhibition only with the addition of Empynase. Four strongly staining protein bands (sizes: 36, 33, 16, and 10 kDa) from Empynase extract were observed to bind to the IgE antibodies of sensitized subjects. Conclusion Exposure to Empynase powder may cause rhinitis and asthma in hospital personnel, and the pathogenic mechanism appears to be IgE mediated.

Occupational rhinitis

PURPOSE OF REVIEW

This review updates existing knowledge on occupational rhinitis based on epidemiological and clinical research studies published from 2003 to 2005.

RECENT FINDINGS

The review covers new developments on the pathophysiology, diagnosis, monitoring and management of occupational rhinitis. This article also provides updated information on the prevalence and incidence of both occupational rhinitis and work-related symptoms of rhinitis, as well as on causal agents and personal risk factors associated with this condition.

SUMMARY

Occupational rhinitis is frequently under-diagnosed due to a lack of physician awareness. Diagnosis is suspected when symptoms occur in relation to work. Differentiating between immunological sensitization and irritation may be difficult. Given the high prevalence of rhinitis in the general population from all causes, objective tests confirming the occupational origin are essential. Measures of inflammatory parameters via nasal lavage and objective assessment of nasal congestion both offer practical means of monitoring responses. Growing experience with acoustic rhinometry and peak nasal inspiratory flow suggests that these methods will have an increasingly important role in monitoring and diagnosing in the future. Recent findings indicate that work-related rhinitis is to some extent preventable. Surveillance of sensitized workers may allow early detection of occupational rhinitis.

Occupational upper airway disease

PURPOSE OF REVIEW

This article reviews recent findings concerning occupational upper airway diseases, which, although very frequent, are usually not considered serious. However, the concept of the 'united airway', evoked during recent years, should change our attitude regarding these diseases. Moreover, new agents in the occupational environment must be characterized. Furthermore, exposure to carcinogens has changed over the years, and in most cases risk should be reassessed.

RECENT FINDINGS

Recent findings concerning work-related upper airway diseases caused by allergens and irritants, and their relationship to lower airway diseases, are reviewed. Findings of studies aimed at characterizing occupational allergens of plant and animal origin are presented. Recognition of work-related upper airway diseases both in clinic and in epidemiological studies is discussed. Current evidence on occupational cancer of the upper airways, its risk factors and changes in them over the years resulting from preventative measures are also described.

SUMMARY

There is significant evidence that occupational allergic diseases of the upper airways can pose important health problems because they represent an early stage of allergy throughout the respiratory system. However, how to detect those rhinitic patients who will develop asthma remains unresolved. New occupational health problems due to irritants were recently reported, and both follow-up studies and evaluations of their implications for the lower airways are warranted. Although preventative measures have been effective to some extent, risk for occupational cancer of the upper airways persists and more targeted epidemiological studies in this area are needed.

Ocular and airway symptoms related to organic acid anhydride exposure--a prospective study

BACKGROUND

Organic acid anhydrides (OAA) are used as hardeners in epoxy resin systems. They are powerful sensitizers giving frequent rhinitis and asthma in exposed workers. Incidence of symptoms is unknown. Here we present the first prospective study on the associations between OAA exposure, symptoms, and effects of confounding factors.

METHODS

All new employees in three plants handling OAA were followed for up to 8.5 years. Before the employment, a questionnaire reporting about symptoms of eyes and airways, smoking habits, and atopy was answered. The subjects were asked at regular medical examinations about work tasks and work-related symptoms. Serum was analysed for specific OAA antibodies.

RESULTS

Mean exposures varied between 6 and 39 microg/m3. The incidence for work-related symptoms of the eyes, nose, pharynx, and lower airways was 91, 64, 46, and 31 per 1000 years of exposure, respectively. Symptoms were found frequently, even at mean exposure level at <10 microg/m3. Smoking and atopy increased the risk of symptoms. Immunoglobulin (Ig)E sensitized workers had a significant increased risk for symptoms of the eyes and pharynx and for running nose/sneezing.

CONCLUSIONS

Organic acid anhydrides exposure is associated with frequent ocular and airway symptoms even at mean exposure levels at <10 microg/m3. There is an important need for establishment of an occupational threshold limit. A limit value of below 5 microg/m3 is proposed.

Respiratory allergy in apprentice bakers: do occupational allergies follow the allergic march?

BACKGROUND

This prospective study describes the incidence, risk factors and natural history of occupational respiratory allergy in apprentice bakers.

METHODS

Two hundred and eighty-seven apprentice bakers were examined using a questionnaire, skin prick tests (SPTs) to common and occupational allergens, evaluation of total serum IgE level and specific anti-flour and alpha-amylase IgE, before, 1 year and 2 years after the onset of vocational training. To diagnose occupational respiratory disease, spirometry, histamine and allergen-specific inhalation challenge tests were performed.

RESULTS

The incidence of work-related chest symptoms was 4.2% in the first year and 8.6% in the second year of exposure. Hypersensitivity to occupational allergens developed in 4.6 and 8.2% of subjects, respectively. The incidence of occupational allergic rhinitis was 8.4% after 1 year and 12.5% after 2 years, and that of occupational asthma/cough-variant asthma 6.1 and 8.7%, respectively. The latency period of work-related rhinitis symptoms was 11.6 +/- 7.1 months and chest symptoms 12.9 +/- 5.5 months. Only in 20% of occupational asthmatics could allergic rhinitis be diagnosed a stage earlier. In 21 out of 25 subjects with occupational asthma, chronic cough was the sole clinical manifestation of the disease. Stepwise logistic regression analysis revealed that positive SPT to common allergens was a significant risk factor of hypersensitivity to occupational allergens (OR = 10.6, 95% CI 5.27; 21.45), occupational rhinitis (OR = 3.9, 95% CI 1.71; 9.14) and occupational asthma (OR = 7.4, 95% CI 3.01; 18.04). Moreover, positive SPT to occupational allergens on entry to the training was a significant risk factor of asthma (OR = 6.9, 95% CI 0.93; 51.38).

CONCLUSIONS

The incidence of occupational asthma and rhinitis in apprentice bakers is high and increases z with the duration of exposure. Skin reactivity to common and occupational allergens is the main risk factor of bakers' asthma. Most cases of work-related respiratory symptoms among apprentice bakers are related to a specific sensitization. In most subjects who developed occupational asthma, rhinitis occurred at the same time as the chest symptoms did.

Occupational asthma

PURPOSE OF REVIEW

The scientific literature on occupational asthma is steadily increasing and no longer only describes case reports with prevalence figures and limited physiopathologic and immunologic data. Prospective cohort studies are currently carried out with relevant incidence figures and risk factors. Genetic susceptibility is explored. New diagnostic means are described. Surveillance programs are conducted and preventive measures are proposed.

RECENT FINDINGS

A relevant account was published on the respiratory consequences (irritant-induced asthma, a type of occupational asthma) of exposure of firefighters at the World Trade Center site. Glutathione-S-transferase appears to be an interesting susceptibility gene for occupational asthma as a result of isocyanates. Inflammation caused by neutrophils and not only by eosinophils is more often associated with occupational asthma. Examination of induced sputum and assessment of exhaled nitric oxide are becoming useful diagnostic tools. Cleaners are at increased risk of developing occupational asthma, although the causal agents are unknown. Surveillance programs currently combine strategies that aim to reduce exposure and identify cases early.

SUMMARY

New scientific information provides better, accurate figures on the frequency of occupational asthma and on risk factors, proposes relevant diagnostic tools more directly related to the physiopathology of the disease, and suggests effective surveillance programs in high-risk workplaces.

Incidence of occupational rhinoconjunctivitis and risk factors in animal-health apprentices

BACKGROUND

Exposure to laboratory animals often causes the appearance of immunologic sensitization and symptoms.

OBJECTIVE

Our aim was to determine the incidence of occupational rhinoconjunctivitis and the timing of symptoms and their determinants in apprentices starting exposure to laboratory animals.

METHODS

Data from 387 (92.8%) of 417 students entering career programs in animal health in 5 schools were kept for analysis. Questionnaires and skin prick tests with common and occupational inhalants were carried out on entry and at follow-up visits scheduled at 8, 20, 32, and 44 months, depending on the schools. Responsiveness to inhaled methacholine was assessed at entry.

RESULTS

Ninety-three (24%) subjects showed incident occupational rhinoconjunctivitis symptoms, and 37 (9.6%) had symptoms combined with skin sensitization to an animal-derived allergen. Symptoms such as sneezing, rhinorrhea, and itchy eyes tended to develop early in the course of exposure. In two thirds of the subjects, symptoms persisted at subsequent visits. In a multivariate analysis the determinants of the appearance of rhinoconjunctivitis with or without allergic sensitization included sensitization to grass pollens (odds ratio [OR], 1.78; 95% CI, 0.99-3.19), as well as nasal (rhinorrhea in contact with dust: OR, 1.79; 95% CI, 1.05-3.05) and bronchial symptoms (chest tightness: OR, 3.31; 95% CI, 0.98-11.25; cough on exposure to strong odors: OR, 1.88; 95% CI, 0.98-3.59).

CONCLUSION

The incidence of occupational rhinoconjunctivitis symptoms with or without immunologic sensitization is high in apprentices starting exposure to laboratory animals. Symptoms related to histamine release are common in the early course of exposure. Determinants include immunologic and target-organ susceptibility.

Rhinoconjunctivitis, bronchial responsiveness, and atopy as determinants for incident non-work-related asthma symptoms in apprentices exposed to high-molecular-weight allergens

OBJECTIVE

The aim of this study was to explore the role of rhinoconjunctivitis (RC), taking into account atopy and the level of bronchial responsiveness to methacholine, on the incidence of respiratory symptoms and in the development and/or worsening of asthma.

METHODS

We examined data from a prospective study in 769 students starting exposure to high-molecular-weight occupational allergens and who were serially followed for up to 44 months.

RESULTS

The presence of RC symptoms at baseline was significantly associated with an increased risk of developing shortness of breath and wheezing in atopic subjects regardless of PC20 level and in subjects with a PC20 <or= 32 mg/ml regardless of atopic status. RC symptoms were significantly associated with the development of exercise-induced respiratory symptoms. Multivariate analyses indicated that having a measurable PC20 was significantly associated with the incidence of all respiratory symptoms studied, whereas baseline seasonal RC was associated only with incident exercise-induced respiratory symptoms; atopy played a minimal role, and only through an interaction with seasonal RC.

CONCLUSION

Of the three potential factors for the development of respiratory symptoms that we considered, i.e. RC symptoms, having a measurable PC20 and atopy, having a measurable PC20 is the most significant one.