Silicosis initially presenting with empyema.

The current global outbreak of artificial stone silicosis is a recrudescence of a major occupational disease in the context of a novel exposure source. Respirable crystalline silica exposure, even without frank pneumoconiosis, is associated with an increased risk of respiratory infection. Empyema is a well-recognized complication of bacterial pneumonia; pneumonia among working-age adults, in turn, has been epidemiologically linked to occupational exposure to fumes and dust, including silica. A connection between empyema and silica dust inhalation has not been reported, however, whether through antecedent pneumonia or another mechanism. We describe a case of silicosis initially presenting with empyema in a 31-year-old Computerized Numerical Control stone-cutting machine operator who had heavy exposure to artificial stone and other rock dust.

Pesticide exposure and lung function: a systematic review and meta-analysis.

BACKGROUND: Epidemiological studies have reported associations between pesticide exposure and respiratory health effects, but the quantitative impact on lung function is unclear. To fill this gap, we undertook a systematic review of the available literature on the association between pesticide exposure and pulmonary function. AIMS: To examine all available literature regarding the relationship between occupational and environmental exposure to pesticides and lung function. METHODS: We searched MEDLINE, EMBASE and Web of Science databases to 1 October 2017 without any date or language restrictions using a combination of MeSH terms and free text for 'pesticide exposure' and 'lung function'. We included studies that met the criteria of our research protocol registered in PROSPERO, and we assessed their quality using a modified Newcastle-Ottawa scale. RESULTS: Of 2356 articles retrieved, 56 articles were included in the systematic review and pooled in meta-analyses for forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC), FVC and FEV1. There was tentative evidence that exposure to cholinesterase (ChE) inhibiting pesticides reduced FEV1/FVC and no evidence that paraquat exposure affected lung function in farmers. CONCLUSIONS: Respiratory surveillance should be enhanced in those exposed to ChE-inhibiting pesticides which reduced FEV1/FVC according to the meta-analysis. Our study is limited by heterogeneity between studies due to different types of exposure assessment to pesticides and potential confounders. Further studies with a more accurate exposure assessment are suggested.

Follow-up survey of patients with occupational asthma.

BACKGROUND: Occupational asthma (OA) is often associated with a poor prognosis and the impact of a diagnosis on an individual's career and income can be significant. AIMS: We sought to understand the consequences of a diagnosis of OA to patients attending our clinic. METHODS: Using a postal questionnaire, we surveyed all patients attending our specialist occupational lung disease clinic 1 year after having received a diagnosis of OA due to a sensitizer (n = 125). We enquired about their current health and employment status and impact of their diagnosis on various aspects of their life. Additional information was collected by review of clinical records. RESULTS: We received responses from 71 (57%) patients; 77% were referred by an occupational health (OH) provider. The median duration of symptoms prior to referral was 18 months (interquartile range (IQR) 8-48). At 1 year, 79% respondents were no longer exposed to the causal agent. Whilst the unexposed patients reported an improvement in symptoms compared with those still exposed (82% versus 53%; P = 0.023), they had poorer outcomes in terms of career, income and how they felt treated by their employer; particularly those not currently employed. Almost all (>90%) of those still employed had been referred by an OH provider compared with 56% of those currently unemployed (P = 0.002)x. CONCLUSIONS: The negative impact of OA on people's careers, livelihood and quality of life should not be underestimated. However, with early detection and specialist care, the prognosis is often good and particularly so for those with access to occupational health.

Different definitions of atopic dermatitis: impact on prevalence estimates and associated risk factors.

BACKGROUND: There is no objective test that can unequivocally confirm the diagnosis of atopic dermatitis (AD), and no uniform clinical definition. OBJECTIVES: To investigate to what extent operational definitions of AD cause fluctuation in the prevalence estimates and the associated risk factors. METHODS: We first reviewed the operational definitions of AD used in the literature. We then tested the impact of the choice of the most common definitions of 'cases' and 'controls' on AD prevalence estimates and associated risk factors (including filaggrin mutations) among children aged 5 years in two population-based birth cohorts: the Manchester Asthma and Allergy Study (MAAS) and Asthma in Ashford. Model performance was measured by the percentage of children within an area of clinical indecision (defined as having a posterior probability of AD between 25% and 60%). RESULTS: We identified 59 different definitions of AD across 45 reviewed studies. Of those, we chose four common 'case' definitions and two definitions of 'controls'. The prevalence estimates using different case definitions ranged between 22% and 33% in MAAS, and between 12% and 22% in Ashford. The area of clinical indecision ranged from 32% to 44% in MAAS and from 9% to 29% in Ashford. Depending on the case definition used, the associations with filaggrin mutations varied, with odds ratios (95% confidence intervals) ranging from 1·8 (1·1-2·9) to 2·2 (1·3-3·7) in MAAS and 1·7 (0·8-3·7) to 2·3 (1·2-4·5) in Ashford. Associations with filaggrin mutations also differed when using the same 'case' definition but different definitions of 'controls'. CONCLUSIONS: Use of different definitions of AD results in substantial differences in prevalence estimates, the performance of prediction models and association with risk factors. What's already known about this topic? There is no objective test that can unequivocally confirm the diagnosis of atopic dermatitis (AD) and no uniform clinical definition. This results in different definitions utilized in AD studies, raising concerns on the generalizability of the results and comparability across different studies. What does this study add? This study has shown that different definitions of 'cases' and 'controls' have major impacts upon prevalence estimates and associations with risk factors, including genetics, in two population-based birth cohorts. These findings suggest the importance of developing a consensus on AD definitions of both 'controls' and 'cases' to minimize biases in studies.

Delayed occupational asthma from epoxy exposure.

BACKGROUND: A delayed asthma reaction occurring several hours after exposure is difficult to diagnose. AIMS: To confirm a delayed asthma reaction in five workers following epoxy exposure. CASE REPORT: Working conditions with exposure to epoxy encountered at the workplace were reproduced in a challenge chamber. Specific inhalation challenge (SIC) with epoxy was compared to a control challenge. All five cases had delayed a asthma response 6-15 h after epoxy exposure. CONCLUSIONS: Our study confirms that SIC is a useful tool in diagnosing delayed asthma response.

Diagnosing occupational asthma.

Making an accurate diagnosis of occupational asthma (OA) is, generally, important. The condition has not only significant health consequences for affected workers, but also substantial socio-economic impacts for workers, their employers and wider society. Missing a diagnosis of OA may lead to continued exposure to a causative agent and progressive worsening of disease; conversely, diagnosing OA when it is not present may lead to inappropriate removal from exposure and unnecessary financial and social consequences. While the most accurate investigation is specific inhalation challenge in an experienced centre, this is a scarce resource, and in many cases, reliance is on other tests. This review provides a technical dossier of the diagnostic value of the available methods which include an appropriate clinical history, the use of specific immunology and measurement of inflammatory markers, and various methods of relating functional changes in airway calibre to periods at work. It is recommended that these approaches are used iteratively and in judicious combination, in cognizance of the individual patient's circumstances and requirements. Based on available evidence, a working diagnostic algorithm is proposed that can be adapted to the suspected agent, purpose of diagnosis and available resources. For better or worse, many of the techniques - and their interpretation - are available only in specialized centres and where there is room for doubt, referral to such a centre is probably wise. Accordingly, the implementation or development of such specialized centres with appropriate equipment and expertise should greatly improve the diagnostic evaluation of work-related asthma.

Chronic obstructive pulmonary disease in Welsh slate miners.

BACKGROUND: Exposure to respirable crystalline silica (RCS) causes emphysema, airflow limitation and chronic obstructive pulmonary disease (COPD). Slate miners are exposed to slate dust containing RCS but their COPD risk has not previously been studied. AIMS: To study the cumulative effect of mining on lung function and risk of COPD in a cohort of Welsh slate miners and whether these were independent of smoking and pneumoconiosis. METHODS: The study was based on a secondary analysis of Medical Research Council (MRC) survey data. COPD was defined as forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) ratio <0.7. We created multivariable models to assess the association between mining and lung function after adjusting for age and smoking status. We used linear regression models for FEV1 and FVC and logistic regression for COPD. RESULTS: In the original MRC study, 1255 men participated (726 slate miners, 529 unexposed non-miners). COPD was significantly more common in miners (n = 213, 33%) than non-miners (n = 120, 26%), P < 0.05. There was no statistically significant difference in risk of COPD between miners and non-miners when analysis was limited to non-smokers or those without radiographic evidence of pneumoconiosis. After adjustment for smoking, slate mining was associated with a reduction in %predicted FEV1 [ß coefficient = -3.97, 95% confidence interval (CI) -6.65, -1.29] and FVC (ß coefficient = -2.32, 95% CI -4.31, -0.33) and increased risk of COPD (odds ratio: 1.38, 95% CI 1.06, 1.81). CONCLUSIONS: Slate mining may reduce lung function and increase the incidence of COPD independently of smoking and pneumoconiosis.

Prevalence of sensitization to 'improver' enzymes in UK supermarket bakers.

BACKGROUND: Supermarket bakers are exposed not only to flour and alpha-amylase but also to other 'improver' enzymes, the nature of which is usually shrouded by commercial sensitivity. We aimed to determine the prevalence of sensitization to 'improver' enzymes in UK supermarket bakers. METHODS: We examined the prevalence of sensitization to enzymes in 300 bakers, employed by one of two large supermarket bakeries, who had declared work-related respiratory symptoms during routine health surveillance. Sensitization was determined using radioallergosorbent assay to eight individual enzymes contained in the specific 'improver' mix used by each supermarket. RESULTS: The prevalence of sensitization to 'improver' enzymes ranged from 5% to 15%. Sensitization was far more likely if the baker was sensitized also to either flour or alpha-amylase. The prevalence of sensitization to an 'improver' enzyme did not appear to be related to the concentration of that enzyme in the mix. CONCLUSIONS: We report substantial rates of sensitization to enzymes other than alpha-amylase in UK supermarket bakers; in only a small proportion of bakers was there evidence of sensitization to 'improver mix' enzymes without sensitization to either alpha-amylase or flour. The clinical significance of these findings needs further investigation, but our findings indicate that specific sensitization in symptomatic bakers may not be identified without consideration of a wide range of workplace antigens.

Changes in the prevalence of cigarette smoking and quitting smoking determinants in adult inhabitants of rural areas in Poland between 2003 and 2012.

OBJECTIVES: We investigate trends in the prevalence of cigarette smoking among adults at all ages in two time points 9 years apart in two neighbouring rural populations and examine social and respiratory health determinants of quitting smoking. STUDY DESIGN: Repeated cross-sectional study. METHODS: Two cross-sectional surveys were conducted in the same rural area of lower Silesia in Poland in 2003 and 2012. A total of 1328 (91% of adult eligible individuals) in 2003 and 1449 (92% of eligible) in 2012 adult inhabitants were surveyed, 908 people (560 villagers and 348 town inhabitants) participated in both surveys. Participants completed a questionnaire on smoking behaviour, education level and respiratory diseases. RESULTS: Current smoking was higher in the villages than the town, among men than women and those with a middle level of education. The prevalence of current smokers decreased over time, although this decline was much more pronounced in the town than in the villages (30.2% vs 23% and 35.5% vs 33.7%, respectively). Men were more likely to stop smoking than women both in villages and in town. The prevalence of current smokers among village women even increased between the two surveys from 27.6% to 29.3%. Respiratory diseases did not influence quitting smoking. CONCLUSIONS: The degree of decreasing trend in smoking prevalence varied considerably within neighbouring populations. It was mainly seen in the town and among younger people. Men and those better educated were more willing to quit smoking. The discrepancies between two close rural populations indicates the need for an individual approach when designing programs of tobacco control.

A new spirometry-based algorithm to predict occupational pulmonary restrictive impairment.

BACKGROUND: Spirometry is often included in workplace-based respiratory surveillance programmes but its performance in the identification of restrictive lung disease is poor, especially when the prevalence of this condition is low in the tested population. AIMS: To improve the specificity (Sp) and positive predictive value (PPV) of current spirometry-based algorithms in the diagnosis of restrictive pulmonary impairment in the workplace and to reduce the proportion of false positives findings and, as a result, unnecessary referrals for lung volume measurements. METHODS: We re-analysed two studies of hospital patients, respectively used to derive and validate a recommended spirometry-based algorithm [forced vital capacity (FVC) < 85% predicted and forced expiratory volume in 1 s (FEV1)/FVC > 55%] for the recognition of restrictive pulmonary impairment. We used true lung restrictive cases as a reference standard in 2×2 contingency tables to estimate sensitivity (Sn), Sp and PPV and negative predictive values for each diagnostic cut-off. We simulated a working population aged <65 years and with a disease prevalence ranging 1-10% and compared our best algorithm with those previously reported using receiver operating characteristic curves. RESULTS: There were 376 patients available from the two studies for inclusion. Our best algorithm (FVC < 70% predicted and FEV1/FVC ≥ 70%) achieved the highest Sp (96%) and PPV (67 and 15% for a disease prevalence of 10 and 1%, respectively) with the lowest proportion of false positives (4%); its high Sn (71%) predicted the highest proportion of correctly classified restrictive cases (91%). CONCLUSIONS: Our new spirometry-based algorithm may be adopted to accurately exclude pulmonary restriction and to possibly reduce unnecessary lung volume testing in an occupational health setting.

Changes in atopy prevalence and sibship effect in rural population at all ages.

BACKGROUND: We examined the associations of family size and birth order with atopy prevalence in rural Poland at two time periods. METHODS: Two cross-sectional surveys were conducted in the same villages and a small town of lower Silesia at an interval of 9 years. In 2003, 1700 (88% of eligible individuals), and in 2012, 1730 (86%) inhabitants aged 5 years or more completed a questionnaire and had a skin prick test for atopy. RESULTS: There was an inverse association between family size and atopy in the village population in 2003; the prevalence of atopy was the highest for those with no siblings (15.2%) and decreased to 5.4% for those with three and more siblings (OR = 0.22; 0.07-0.66). In contrast, there was little or no such protective effect in the town population where the prevalence of atopy was much higher (7.3% in the villages, 20.0% in the town). Nine years later, the prevalence of atopy had increased in the village to be similar to that in the town (19.6% and 19.9% respectively), and the protective effects of family size and birth order in the villages were much weaker (OR = 0.64; 95% CI 0.33-1.27 for three or more siblings). Both protective effects were strongest among children. CONCLUSIONS: The protective effects of family size and birth order on atopy were much stronger in children than in adults and among those living in a village. They largely disappeared with the steep increase in atopy prevalence at all ages; this followed environmental changes on the village farms.

Occupational asthma from tafenoquine in the pharmaceutical industry: implications for QSAR.

We report occupational asthma and rhinitis in a formulation pharmacist, employed in the development of tafenoquine. Tafenoquine is a new anti-malarial drug in development; the pure drug substance has an asthma hazard index of zero and previously was not known to be a respiratory sensitizing agent. The implications of this finding for the refinement of quantitative structural analysis of asthmagenic chemicals are discussed.

EAACI Position Paper on assessment of cough in the workplace.

Cough is a nonspecific and relatively common symptom that can present difficulties in diagnosis and management, particularly when it is reported to be associated with the workplace. The present consensus document, prepared by a taskforce of the Interest Group on Occupational Allergy of the European Academy of Allergy and Clinical Immunology by means of a nonsystematic review of the current literature, is intended to provide a definition and classification of work-related chronic cough (WRCC) to assist the daily practice of physicians facing with this symptom. The review demonstrates that several upper and lower airway work-related diseases may present with chronic cough; hence, the possible link with the workplace should always be considered. Due to the broad spectrum of underlying diseases, a multidisciplinary approach is necessary to achieve a definite diagnosis. Nevertheless, more epidemiological studies are necessary to estimate the real prevalence and risk factors for WRCC, the role of exposure to environmental and occupational sensitizers and irritants in its pathogenesis and the interaction with both upper and lower airways. Finally, the best management option should be evaluated in order to achieve the best outcome without adverse social and financial consequences for the worker.

Rat-specific IgG and IgG4 antibodies associated with inhibition of IgE-allergen complex binding in laboratory animal workers.

OBJECTIVES: The relationship between exposure to rodent allergens and laboratory animal allergy is complex; at highest allergen exposures there is an attenuation of sensitisation and symptoms which are associated with increased levels of rat-specific immunoglobulin (Ig)G and IgG4 antibodies. We set out to examine whether the increased levels of rat-specific IgG and IgG4 antibodies that we have previously observed at high allergen exposure in our cohort of laboratory animal workers play a functional role through blockage of the binding of IgE-allergen complex binding to CD23 receptors on B cells. METHODS: Cross-sectional survey of laboratory animal workers (n=776) in six UK pharmaceutical companies were surveyed. IgE-allergen complex binding to B cells was measured in 703 (97.9%) eligible employees; their exposure was categorised by either job group or number of rats handled daily. RESULTS: We observed a significant decrease in IgE-allergen complex binding to B cells with increasing quartiles of both rat-specific IgG and IgG4 antibodies (p<0.001). IgE-allergen complex binding to B cells was lower in workers with high allergen exposure, and significantly so (p=0.033) in the subgroup with highest exposures but no work-related chest symptoms. CONCLUSIONS: These findings demonstrate a functional role for rat-specific IgG/G4 antibodies in laboratory animal workers, similar to that observed in patients treated with high dose immunotherapy who become clinically tolerant, suggesting a potential explanation for the attenuation of risk at highest allergen exposures.

Respiratory protective equipment reduces occurrence of sensitization to laboratory animals.

BACKGROUND: Respiratory protective equipment (RPE) has been shown to reduce exposure to laboratory animal allergens, but there are no studies that have examined its effect on the development of sensitization. AIMS: To examine the effect of RPE on the risk of sensitization to laboratory animals. METHODS: Survey of UK laboratory animal workers conducted between 1999 and 2001. Information was recorded on the type of RPE used when first exposed to animals and at the time of the survey. Sensitization to rat urinary proteins was assessed using skin-prick tests and assays of specific serum IgE antibodies. RESULTS: There were 776 workers surveyed of whom 228 had been exposed for fewer than 5 years. Those more recently employed were more likely to have used RPE. In employees with <5 years of exposure the use of face masks at first employment was associated with a lower prevalence of sensitization, irrespective of the intensity of exposure to laboratory animals. This reduction was significant only in those who entered the animal house daily. CONCLUSIONS: The use of simple RPE at first exposure to laboratory animals may help to reduce the incidence of specific sensitization.

Consumption of unpasteurized milk and its effects on atopy and asthma in children and adult inhabitants in rural Poland.

BACKGROUND: Consumption of unpasteurized cow's milk has been identified as a possible protective factor for atopy and asthma. Most studies have been conducted among children and in farming populations. We investigated the effects of consumption of unpasteurized milk in early life on atopy, asthma, and rhinitis in village and town inhabitants in a region of Poland and assessed whether any protective effects of milk consumption differed according to place of residence and farming status. METHODS: We surveyed the inhabitants (aged >5 years) of a small town and seven nearby villages in southwest Poland (n = 1700, response rate 88%). Participants (or their parents for those <16 years of age) completed a questionnaire on farm exposures and symptoms of asthma and rhinitis. In particular, information was collected on unpasteurized milk consumption in early life. Atopy was assessed using skin prick tests. RESULTS: Consumption of unpasteurized milk in the first year of life was inversely associated with atopy and asthma both among town and village inhabitants - town: adjusted odds ratio (aOR) for atopy 0.46 [95% confidence interval (CI) 0.37-0.52] asthma 0.51 (0.32-0.74); villages: atopy 0.59 (0.44-0.70) and asthma 0.59 (0.42-0.74). For atopy, the protective effect was more clearly seen among nonfarmers (0.42; 0.34-0.46) than in farmers (0.82; 0.54-1.11). For doctor-diagnosed hay fever and current rhinitis symptoms, the protective effect was only observed among town inhabitants and/or nonfarmers. CONCLUSIONS: Early-life exposure to unpasteurized milk may protect against atopy, asthma, and related conditions, independently of place of residence and farming status, and in both children and adults.

Airway dysfunction in elite athletes--an occupational lung disease?

Airway dysfunction is prevalent in elite endurance athletes and when left untreated may impact upon both health and performance. There is now concern that the intensity of hyperpnoea necessitated by exercise at an elite level may be detrimental for an athlete's respiratory health. This article addresses the evidence of causality in this context with the aim of specifically addressing whether airway dysfunction in elite athletes should be classified as an occupational lung disease. The approach used highlights a number of concerns and facilitates recommendations to ensure airway health is maintained and optimized in this population. We conclude that elite athletes should receive the same considerations for their airway health as others with potential and relevant occupational exposures.

Association of maternal anti-HLA class II antibodies with protection from allergy in offspring.

BACKGROUND: Recent studies have suggested that the birth order effect in allergy may be established during the prenatal period and that the protective effect may originate in the mother. HLA class II disparity between mother and foetus has been associated with significantly increased Th1 production. In this study, we investigated whether production of HLA antibodies 4 years after pregnancy with index child is associated with allergic outcomes in offspring at 8 years. METHODS: Anti-HLA class I and II antibodies were measured in maternal serum (n = 284) and levels correlated to numbers of pregnancies and birth order, and allergic outcomes in offspring at 8 years of age. RESULTS: Maternal anti-HLA class I and II antibodies were significantly higher when birth order, and the number of pregnancies were larger. Anti-HLA class II, but not class I antibodies were associated with significantly less atopy and seasonal rhinitis in the offspring at age 8 years. Mothers with nonatopic (but not atopic) offspring had a significant increase in anti-HLA class I and II antibodies with birth order. CONCLUSION: This study suggests that the 'birth order' effect in children may be due to parity-related changes in the maternal immune response to foetal antigens. We have observed for the first time an association between maternal anti-HLA class II antibodies and protection from allergy in the offspring. Further work is required to determine immunologically how HLA disparity between mother and father can protect against allergy.

Asthma and allergies: is the farming environment (still) protective in Poland? The GABRIEL Advanced Studies.

BACKGROUND: Evidence exists that a farming environment in childhood may provide protection against atopic respiratory disease. In the GABRIEL project based in Poland and Alpine regions of Germany, Austria and Switzerland, we aimed to assess whether a farming environment in childhood is protective against allergic diseases in Poland and whether specific exposures explain any protective effect. METHODS: In rural Poland, 23 331 families of schoolchildren completed a questionnaire enquiring into farming practices and allergic diseases (Phase I). A subsample (n = 2586) participated in Phase II involving a more detailed questionnaire on specific farm exposures with objective measures of atopy. RESULTS: Farming differed between Poland and the Alpine centres; in the latter, cattle farming was prevalent, whereas in Poland 18% of village farms kept ≥1 cow and 34% kept ≥1 pig. Polish children in villages had lower prevalences of asthma and hay fever than children from towns, and in the Phase II population, farm children had a reduced risk of atopy measured by IgE (aOR = 0.72, 95% CI 0.57, 0.91) and skin prick test (aOR = 0.65, 95% CI 0.50, 0.86). Early-life contact with grain was inversely related to the risk of atopy measured by IgE (aOR = 0.66, 95% CI 0.47, 0.92) and appeared to explain part of the farming effect. CONCLUSION: While farming in Poland differed from that in the Alpine areas as did the exposure-response associations, we found in communities engaged in small-scale, mixed farming, there was a protective farming effect against objective measures of atopy potentially related to contact with grain or associated farm activities.

Occupational management of type I latex allergy.

BACKGROUND: Although the incidence of type 1 latex allergy has decreased in recent years with the introduction of powder-free low-protein (PFLP) latex gloves, type 1 latex allergy is still commonly found among workers who use natural rubber latex (NRL) gloves at work. AIMS: To elucidate the optimal management of workers with type 1 latex allergy whose work necessitates the use of NRL gloves in the workplace. METHODS: A sensitive electronic search of relevant bibliographic databases was performed with related search terms for articles from 1 January 1990 to 1 September 2010. Relevant abstracts were reviewed, and studies that furnished data on the management of type 1 latex allergy in the workplace were extracted. Articles for inclusion in the review were appraised using the Scottish Intercollegiate Guideline Network methodology. RESULTS: A total of 7041 abstracts were retrieved; 12 articles met the inclusion criteria for the review. We found moderately strong and consistent evidence that avoidance of NRL in the workplace reduces both symptoms and markers of sensitization in latex-allergic individuals. There is limited evidence that latex-allergic workers can continue to use PFLP gloves with no worsening of symptoms, provided that their co-workers also use PFLP latex or non-latex gloves. CONCLUSIONS: Individuals with type 1 latex allergy whose work necessitates them wearing latex gloves may continue in their job provided that adjustments are made to ensure that they are not exposed to powdered latex gloves.