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BACKGROUND: At present there is no internationally agreed definition of occupational asthma and there is a lack of guidance regarding the resources that should be readily available to physicians running specialist occupational asthma services. AIMS: To agree a working definition of occupational asthma and to develop a framework of resources necessary to run a specialist occupational asthma clinic. METHOD: A modified RAND appropriateness method was used to gain a consensus of opinion from an expert panel of clinicians running specialist occupational asthma clinics in the UK. RESULTS: Consensus was reached over 10 terms defining occupational asthma including: occupational asthma is defined as asthma induced by exposure in the working environment to airborne dusts vapours or fumes, with or without pre-existing asthma; occupational asthma encompasses the terms 'sensitiser-induced asthma' and 'acute irritant-induced asthma' (reactive airways dysfunction syndrome (RADS)); acute irritant-induced asthma is a type of occupational asthma where there is no latency and no immunological sensitisation and should only be used when a single high exposure has occurred; and the term 'work-related asthma' can be used to include occupational asthma, acute irritant-induced asthma (RADS) and aggravation of pre-existing asthma. Disagreement arose on whether low dose irritant-induced asthma existed, but the panel agreed that if it did exist they would include it in the definition of 'work-related asthma'. The panel agreed on a set of 18 resources which should be available to a specialist occupational asthma service. These included pre-bronchodilator FEV1 and FVC (% predicted); peak flow monitoring (and plotting of results, OASYS II analysis); non-specific provocation challenge in the laboratory and specific IgE to a wide variety of occupational agents. CONCLUSION: It is hoped that the outcome of this process will improve uniformity of definition and investigation of occupational asthma across the UK. [ABSTRACT FROM AUTHOR]

Reproterol is a synthetic selective beta-adrenoceptor agonist with a xanthine side chain. The bronchial and cardiovascular responses to inhaled reproterol were studied in 14 asthmatics. The study was placebo controlled and double-blind, comparing doubling doses of reproterol from 500 micrograms-8 mg. The peak improvement in FEV1 showed a non- linear dose-response, with an initial plateau at the 1 mg dose producing a mean increase in FEV1 of 17%, but significant further improvement at the 8 mg dose, producing a mean improvement of 29% in FEV1. The time taken for improvement in airways obstruction to start shortened with increasing doses. The duration of bronchodilation was dose-dependent, with the 8 mg dose showing a significantly longer duration of action than the lower doses. The time to drop below 75% of the maximum achieved bronchodilation was 125 min, and was independent of the dose. There were no significant changes in pulse or blood pressure at any dose. The study shows that reproterol is a well tolerated selective beta 2-adrenoceptor agonist whose duration of action and peak effect can be significantly increased by increasing the dose to 8 mg, without producing more unwanted effects. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) is irreversible and causes a progressive reduction in physical functioning. There is evidence that emotional distress contributes to loss of function and that improvements may be obtained via psychologically based interventions to alleviate anxiety and panic. This systematic review examined the most effective interventions to date. A literature search revealed 25 studies; these were assessed using standardised criteria for inclusion and quality. Six randomised, controlled trials fulfilled the criteria, but the variety of methods, interventions and measures prevented the use of a meta-analysis. Two studies were unpublished doctoral theses, four were published studies. All of the studies had one or more deficiencies; failure to measure or report lung function, large variation in attrition, lack of blinding in assessment of treatment outcome, lack of use of standardised anxiety measures. Description of the intervention was not always sufficient to allow replication. There were no trials of interventions aimed at reducing panic. No study was adequately designed to provide an assessment of psychological intervention aimed at anxiety in COPD. Secondary outcomes included impacts on breathlessness, disability and quality of life. It can be concluded that currently there is insufficient research of quality on which to base recommendations for effective interventions for anxiety and panic in COPD. Future research should tie the design of evaluation to interventions based on theories of the relationship between dyspnoea and anxiety. [ABSTRACT FROM AUTHOR]

The aetiology and pathophysiology of sarcoidosis is ill defined-current hypotheses centre on complex genetic-immune-environmental interactions in an individual, triggering a granulomatous process. The aim of this systematic review is to define and describe which airborne occupational exposures (aOE) are associated with and precede a diagnosis of pulmonary sarcoidosis. The methodology adopted for the purpose was systematic review and meta-analyses of ORs for specified aOE associated with pulmonary sarcoidosis (DerSimonian Laird random effects model (pooled log estimate of OR)). Standard search terms and dual review at each stage occurred. A compendium of aOE associated with pulmonary sarcoidosis was assembled, including mineralogical studies of sarcoidosis granulomas. N=81 aOE were associated with pulmonary sarcoidosis across all study designs. Occupational silica, pesticide and mould or mildew exposures were associated with increased odds of pulmonary sarcoidosis. Occupational nickel and aluminium exposure were associated with a non-statistically significant increase in the odds of pulmonary sarcoidosis. Silica exposure associated with pulmonary sarcoidosis was reported most frequently in the compendium (n=33 studies) and was the most common mineral identified in granulomas. It was concluded that aOE to silica, pesticides and mould or mildew are associated with increased odds of pulmonary sarcoidosis. Equipoise remains concerning the association and relationship of metal dusts with pulmonary sarcoidosis., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Office work has a relative perception of safety for the worker. Data from surveillance schemes and population-based epidemiological studies suggest that office work carries a low risk of occupational asthma (OA). Office workers are frequently used as comparators in studies of occupational exposure and respiratory disease., Aims: We aimed to describe and illustrate our tertiary clinical experience of diagnosing OA in office workers., Methods: We searched the Birmingham NHS Occupational Lung Disease Service clinical database for cases of occupational respiratory disease diagnosed between 2002 and 2020, caused by office work or in office workers. For patients with OA, we gathered existing data on demographics, diagnostic tests including Occupational Asthma SYStem (OASYS) analysis of serial peak expiratory flow and specific inhalational challenge, and employment outcome. We summarised data and displayed them alongside illustrative cases., Results: There were 47 cases of OA (5% of all asthma) confirmed using OASYS analysis of PEFs in the majority. Sixty percent of cases occurred in healthcare, education and government sectors. The most frequently implicated causative exposures or agents were: indoor air (9), printing, copying and laminating (7), cleaning chemicals (4), mould and damp (4), and acrylic flooring and adhesives (4). Exposures were grouped into internal office environment, office ventilation-related and adjacent environment., Conclusions: Clinicians should be vigilant for exposures associated with OA in office workers who present with work-related symptoms, where respiratory sensitizing agents may be present. A structured approach to assessment of the workplace is recommended., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: The COVID-19 pandemic follows severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronavirus epidemics. Some survivors of COVID-19 infection experience persistent respiratory symptoms, yet their cause and natural history remain unclear. Follow-up after SARS and MERS may provide a model for predicting the long-term pulmonary consequences of COVID-19., Methods: This systematic review and meta-analysis aims to describe and compare the longitudinal pulmonary function test (PFT) and computed tomography (CT) features of patients recovering from SARS, MERS and COVID-19. Meta-analysis of PFT parameters (DerSimonian and Laird random-effects model) and proportion of CT features (Freeman-Tukey transformation random-effects model) were performed., Findings: Persistent reduction in the diffusing capacity for carbon monoxide following SARS and COVID-19 infection is seen at 6 months follow-up, and 12 months after MERS. Other PFT parameters recover in this time. 6 months after SARS and COVID-19, ground-glass opacity, linear opacities and reticulation persist in over 30% of patients; honeycombing and traction dilatation are reported less often. Severe/critical COVID-19 infection leads to greater CT and PFT abnormality compared to mild/moderate infection., Interpretation: Persistent diffusion defects suggestive of parenchymal lung injury occur after SARS, MERS and COVID-19 infection, but improve over time. After COVID-19 infection, CT features are suggestive of persistent parenchymal lung injury, in keeping with a post-COVID-19 interstitial lung syndrome. It is yet to be determined if this is a regressive or progressive disease., Competing Interests: Conflict of interest: C.C. Huntley reports receiving support for attending meetings and/or travel from Boehringer Ingelheim outside the submitted work. K. Patel reports receiving support for attending meetings and/or travel from GSK outside the submitted work. C.B. Knight reports support for the present manuscript received from The Sir Arthur Thomson Trust Vacation Studentship. The remaining authors have nothing to disclose., (Copyright ©The authors 2022.)

Objectives: To identify the changes in serial 2-hourly forced expiratory volume in 1 s (FEV 1 ) measurements required to identify occupational asthma (OA) using the Oasys Area Between Curves (ABC) score., Methods: The ABC score from 2-hourly measurements of FEV 1 was compared between workers with confirmed OA and asthmatics without occupational exposure to identify the optimum separation using receiver operator characteristic (ROC) analysis. Separate analyses were made for plots using clock time and time from waking to allow for use in shift workers. Minimum record criteria were ≥6 readings per day, >4 day shifts and >4 rest days (or >9 days for controls)., Results: A retrospective analysis identified 22 workers with OA and 30 control asthmatics whose records reached the quality standards. Median FEV 1 diurnal variation was 20.3% (IQR 16.1-32.6) for OA and 19.5% (IQR 14.5-26.1) for asthmatic controls. ROC curve analysis identified that a difference of 0.056 L/hour gave a ROC score of 0.821 for clock time and 0.768 for time from waking with a sensitivity of 73% and a specificity of 93% for the diagnosis of OA., Conclusions: The diagnosis of OA requires objective confirmation. Unsupervised serial FEV 1 measurements are more difficult to obtain reliably than measurements of peak expiratory flow, which are likely to remain the standard for general use. A FEV 1 ABC score >0.056 L/hour provides a valid cut-off for those who wish to use FEV 1 rather than peak expiratory flow., Competing Interests: Competing interests: PSB and VCM have developed with others the Oasys analytical system used in this paper. It is open access on www.occupationalasthma.com without payment or qualification., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Specific inhalation challenge (SIC) is the reference standard for the diagnosis of occupational asthma. Current guidelines for identifying late asthmatic reactions are not evidence based., Objectives: To identify the fall in forced expiratory volume in 1 s (FEV 1 ) required following SIC to exceed the 95% CI for control days, factors which influence this and to show how this can be applied in routine practice using a statistical method based on the pooled SD for FEV 1 from three control days., Methods: Fifty consecutive workers being investigated for occupational asthma were asked to self-record FEV 1 hourly for 2 days before admission for SIC. These 2 days were added to the in-hospital control day to calculate the pooled SD and 95% CI., Results: 45/50 kept adequate measurements. The pooled 95% CI was 385 mL (SD 126), or 14.2% (SD 6.2) of the baseline FEV 1 , but was unrelated to the baseline FEV 1 (r=0.06, p=0.68), or gender, atopy, smoking, non-specific reactivity or treatment before or during SIC. Thirteen workers had a late asthmatic reaction with ≥2 consecutive FEV 1 measurements below the 95% CI for pooled control days, 4/13 had <15% and 9/13 >15% late fall from baseline. The four workers with ≥2 values below the 95% CI all had independent evidence of occupational asthma., Conclusion: The pooled SD method for defining late asthmatic reactions has scientific validity, accounts for interpatient spirometric variability and diurnal variation and can identify clinically relevant late asthmatic reactions from smaller exposures. For baseline FEV 1 <2.5 L, a 15% fall is within the 95% CI., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Establishing whether patients are exposed to a 'known cause' is a key element in both the diagnostic assessment and the subsequent management of hypersensitivity pneumonitis (HP)., Objective: This study surveyed British interstitial lung disease (ILD) specialists to document current practice and opinion in relation to establishing causation in HP., Methods: British ILD consultants (pulmonologists) were invited by email to take part in a structured questionnaire survey, to provide estimates of demographic data relating to their service and to rate their level of agreement with a series of statements. A priori 'consensus agreement' was defined as at least 70% of participants replying that they 'Strongly agree' or 'Tend to agree'., Results: 54 consultants took part in the survey from 27 ILD multidisciplinary teams. Participants estimated that 20% of the patients in their ILD service have HP, and of these, a cause is identifiable in 32% of cases. For patients with confirmed HP, an estimated 40% have had a bronchoalveolar lavage for differential cell counts, and 10% a surgical biopsy. Consensus agreement was reached for 25 of 33 statements relating to causation and either the assessment of unexplained ILD or management of confirmed HP., Conclusions: This survey has demonstrated that although there is a degree of variation in the diagnostic approach for patients with suspected HP in Britain, there is consensus opinion for some key areas of practice. There are several factors in clinical practice that currently act as potential barriers to identifying the cause for British HP patients., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: Occupational exposures are a common cause of adult-onset asthma; rapid removal from exposure to the causative agent offers the best chance of a good outcome. Despite this, occupational asthma (OA) is widely underdiagnosed. We aimed to see whether chances of diagnosis were missed during acute hospital attendances in the period between symptom onset and the diagnosis of OA., Methods: Patients diagnosed with OA at the regional occupational lung disease service in Birmingham between 2007 and 2018 whose home address had a Birmingham postcode were included. Emergency department (ED) attendances and acute admission data were retrieved from acute hospitals in the Birmingham conurbation for the period between symptom onset and diagnosis., Results: OA was diagnosed in 406 patients, 147 having a Birmingham postcode. Thirty-four percent (50/147) had acute hospital attendances to a Birmingham conurbation hospital preceding their diagnosis of OA, including 35 (24%) with respiratory illnesses, which resulted in referral for investigation of possible OA in 2/35. The median delay between symptom onset and diagnosis of OA was 30 months (IQR = 13-60) and between first hospital attendance with respiratory illness and diagnosis 12 months (IQR = 12-48, range 3-96 months) CONCLUSIONS: The chance to reduce the delay in the diagnosis of OA was missed in 33/35 patients admitted or seen in ED with respiratory symptoms in the period between symptom onset and diagnosis of OA. The diagnosis of OA was delayed by a median of 12 months by failure to ask about employment and work relationship of symptoms.

Background: Evidence-based reviews have found that evidence for the efficacy of respiratory protective equipment (RPE) in the management of occupational asthma (OA) is lacking., Aims: To quantify the effectiveness of air-fed RPE in workers with sensitizer-induced OA exposed to metal-working fluid aerosols in a car engine and transmission manufacturing facility., Methods: All workers from an outbreak of metal-working fluid-induced OA who had continuing peak expiratory flow (PEF) evidence of sensitizer-induced OA after steam cleaning and replacement of all metal-working fluid were included. Workers kept 2-hourly PEF measurements at home and work, before and after a strictly enforced programme of RPE with air-fed respirators with charcoal filters. The area-between-curve (ABC) score from the Oasys plotter was used to assess the effectiveness of the RPE., Results: Twenty workers met the inclusion criteria. Records were kept for a mean of 24.6 day shifts and rest days before and 24.7 after the institution of RPE. The ABC score improved from 26.6 (SD 16.2) to 17.7 (SD 25.4) l/min/h (P > 0.05) post-RPE; however, work-related decline was <15 l/min/h in only 12 of 20 workers, despite increased asthma treatment in 5 workers., Conclusions: Serial PEF measurements assessed with the ABC score from the Oasys system allowed quantification of the effect of RPE in sensitized workers. The RPE reduced falls in PEF associated with work exposure, but this was rarely complete. This study suggests that RPE use cannot be relied on to replace source control in workers with OA, and that monitoring post-RPE introduction is needed., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Introduction: The causes of hypersensitivity pneumonitis (HP) in the UK are changing as working practices evolve, and metalworking fluid (MWF) is now a frequently reported causative exposure. We aimed to review and describe all cases of HP from our UK regional service, with respect to the causative exposure and diagnostic characteristics., Methods: In a retrospective, cross-sectional study, we collected patient data for all 206 cases of HP diagnosed within our UK-based regional NHS interstitial and occupational lung disease service, 2002-17. This included demographics, environmental and occupational exposures, clinical features, and diagnostic tests (CT imaging, bronchiolo-alveolar cell count, lung function, histology). We grouped the data by cause (occupational, non-occupational and unknown) and by presence or absence of fibrosis on CT, in order to undertake hypothesis testing., Results: Cases were occupational (n = 50), non-occupational (n = 56) or cryptogenic (n = 100) in aetiology. The commonest causes were birds = 37 (18%) and MWF = 36 (17%). Other occupational causes included humidifiers and household or commercial waste, but only one case of farmers' lung. Cryptogenic cases were associated with significantly older age, female gender, lower lung function parameters, fewer alveolar lymphocyte counts >20%, and fibrosis on CT; exposure information was missing in 22-33% of cryptogenic cases., Conclusion: MWF is the commonest occupational cause of HP, where workers usually present with more acute/subacute features and less fibrosis on CT; refuse work is an emerging cause. Cryptogenic HP has a fibrotic phenotype, and a full occupational history should be taken, as historical workplace exposures may be relevant., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

Background: Healthcare practice in the UK has moved away from using aldehyde disinfectants for the decontamination of endoscopes, in part due to the risk of respiratory sensitization. Peracetic acid (PAA) in combination with hydrogen peroxide (HP) is a commonly used alternative., Aim: We describe a case of occupational asthma (OA) diagnosed at our specialist occupational lung disease clinic and caused by occupational exposure to PAA-HP mixture, used as a disinfectant in an endoscope washer-disinfector machine., Case Report: A 48-year-old man employed as a mycologist and environmental microbiologist at a Birmingham city hospital, UK, presented following an acute exposure to PAA-HP mixture causing lacrimation, burning optic pain and headache. He had also experienced symptoms suggestive of OA for the preceding 10 months, and the diagnosis was confirmed through OASYS analysis of serial peak expiratory flow measurements. He had been exposed to PAA-HP mixture whilst working in the endoscopy department for 12 months prior to the acute episode, and a subsequent specific inhalation challenge test was positive with a late asthmatic response to PAA-HP mixture., Conclusion: This case provides evidence for a sensitization mechanism in OA caused by PAA-HP mixture., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Cleaning agents are now a common cause of occupational asthma (OA) worldwide. Irritant airway and sensitization mechanisms are implicated for a variety of old and new agents., Aims: To describe the exposures responsible for cleaning agent OA diagnosed within a UK specialist occupational lung disease service between 2000 and 2016., Methods: The Birmingham NHS Occupational Lung Disease Service clinical database was searched for cases of OA caused by cleaning agents, and data were gathered on age, gender, atopic status, smoking history, symptom onset, diagnostic investigations (including Occupational Asthma SYStem analysis of workplace serial peak expiratory flow measurements and specific inhalational challenge), proposed mechanism, industry, occupation and causative agent., Results: Eighty patients with cleaning agent OA (77% female, 76% arising de novo) were identified. The median annual number of cases was 4 (interquartile range = 2-7). The commonest cleaning agents causing OA were chloramines (31%), glutaraldehyde (26%) and quaternary ammonium compounds (11%) and frequently implicated industries were healthcare (55%), education (18%) and leisure (8%)., Conclusions: Certain cleaning agents in common usage, such as chlorine-releasing agents, quaternary ammonium compounds and aldehydes, are associated with sensitization and asthma. Their use alters over time, and this is particularly evident in UK healthcare where cleaning and decontamination practice and policy have changed. Vigilance for OA in workplaces such as hospitals, nursing homes, leisure centres and swimming pools, where these cleaning agents are regularly used, is therefore essential.

A young female vaper presented with insidious onset cough, progressive dyspnoea on exertion, fever, night sweats and was in respiratory failure when admitted to hospital. Clinical examination was unremarkable. Haematological tests revealed only thrombocytopenia, which was long standing, and her biochemical and inflammatory markers were normal. Chest radiograph and high-resolution CT showed diffuse ground-glass infiltrates with reticulation. She was initially treated with empirical steroids and there was improvement in her oxygenation, which facilitated further tests. Since the bronchoscopy and high-volume lavage was unyielding, a video-assisted thoracoscopicsurgical biopsy was done later and was suggestive of lipoid pneumonia. The only source of lipid was the vegetable glycerine found in e-cigarette (EC). Despite our advice to quit vaping, she continued to use EC with different flavours and there is not much improvement in her clinical and spirometric parameters., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2018. No commercial re-use. See rights and permissions. Published by BMJ.)

Specific inhalation challenge (SIC) is the diagnostic reference standard for occupational asthma; however, a positive test cannot be considered truly significant unless it can be reproduced by usual work exposures. We have compared the timing and responses during SIC in hospital to Oasys analysis of serial peak expiratory flow (PEF) during usual work exposures.All workers with a positive SIC to occupational agents between 2006 and 2015 were asked to measure PEF every 2 h from waking to sleeping for 4 weeks during usual occupational exposures. Responses were compared between the laboratory challenge and the real-world exposures at work.All 53 workers with positive SIC were included. 49 out of 53 had records suitable for Oasys analysis, 14 required more than one attempt and all confirmed occupational work-related changes in PEF. Immediate SIC reactors and deterioration within the first 2 h of starting work were significantly correlated with early recovery, and late SIC reactors and a delayed start to workplace deterioration were significantly correlated with delayed recovery. Dual SIC reactions had features of immediate or late SIC reactions at work rather than dual reactions.The concordance of timings of reactions during SIC and at work provides further validation for the clinical significance of each test., Competing Interests: Conflict of interest: None declared., (Copyright ©ERS 2018.)

A diagnosis of asbestosis, which is a long-latency, fibrotic lung disease, has implications for the patient in terms of prognosis, treatment and compensation. Identifying and quantifying asbestos exposure is difficult without a detailed occupational history, and the threshold dose of asbestos required to cause asbestosis is not well understood. We reviewed all cases of asbestosis diagnosed between 2001 and 2016 at the Birmingham Regional NHS Occupational Lung Disease Service to determine the industries and occupations most frequently implicated in causation, in order to help clinicians identify where asbestosis might enter the differential diagnosis for a patient with chronic respiratory symptoms. A variety of construction trades were frequently reported including carpenters and joiners, pipe fitters, laggers, labourers, painters and shop fitters. Traditionally heavily exposed occupations such as shipbuilding were not commonly seen.

Competing Interests: Competing interests: None declared.

Background: We present the case of a 35-year-old male who developed a chronic hypersensitivity pneumonitis (HP) following inhalational exposure to a fluorocarbon waterproofing aerosol spray, caused by his work for an upholstery and soft furnishings retailer. This is the first case report from inhalational fluorocarbon exposure with histological evidence of chronic HP. This is then discussed in the context of previous reports of interstitial lung disease and lung injury, caused by similar occupational and non-occupational exposures., (© The Author 2017. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

Background: Acrylic monomers (acrylates), methacrylates and cyanoacrylates all cause asthma by respiratory sensitization. Occupational inhalation exposures occur across a variety of industries including health care and dental work, beauty, laboratory science, assembly and plastic moulding., Aims: To examine notifications of occupational asthma caused by acrylic compounds from a UK-based regional surveillance scheme, in order to highlight prevalent exposures and trends in presentation., Methods: Retrospective review of all cases reported to the SHIELD surveillance scheme for occupational asthma, West Midlands, UK between 1989 and 2014. Patient data were gathered on demographics, employment, asthma symptoms and diagnostic investigations including serum immunological testing, serial peak flow analysis and specific inhalation challenge tests. Descriptive statistics were used to illustrate worker characteristics and evidence for sensitization to acrylic compounds., Results: There were 20 affected patients out of 1790 total cases of occupational asthma (1%); all cases were confirmed by OASYS (Occupational Asthma SYStem) analysis of serial peak flow measurements, with three additional positive specific inhalation challenge tests. Three out of 20 (15%) patients were current smokers and 11/20 (55%) were atopic. A variety of exposures and industries were implicated including: manufacturing, health care, beauty and printing and a novel presentation seen in teachers exposed to floor adhesives., Conclusions: This is the largest reported series of occupational asthma caused by acrylic compounds, which remain an important aetiological factor in this disease. Exposure occurs in a variety of industries, particularly in manufacturing and is seen with other, perhaps better recognized sensitizing agents such as isocyanates and epoxy resins., (© The Author 2017. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

Objectives: The use of genetically engineered enzymes in the synthesis of flavourings, fragrances and other applications has increased tremendously. There is, however, a paucity of data on sensitisation and/or allergy to the finished products. We aimed to review the use of genetically modified enzymes and the enormous challenges in human biomonitoring studies with suitable assays of specific IgE to a variety of modified enzyme proteins in occupational settings and measure specific IgE to modified enzymes in exposed workers., Methods: Specific IgE antibodies against workplace-specific individual enzymes were measured by the specific fluorescence enzyme-labelled immunoassay in 813 exposed workers seen in cross-sectional surveys., Results: Twenty-three per cent of all exposed workers showed type I sensitisation with IgE antibodies directed against respective workplace-specific enzymes. The highest sensitisation frequencies observed were for workers exposed enzymes derived from α-amylase (44%), followed by stainzyme (41%), pancreatinin (35%), savinase (31%), papain (31%), ovozyme (28%), phytase (16%), trypsin (15%) and lipase (4%). The highest individual antibody levels (up to 110 kU/L) were detected in workers exposed to phytase, xylanase and glucanase. In a subgroup comprising 134 workers, detailed clinical diagnostics confirmed work-related symptoms. There was a strong correlation (r=0.75, p<0.0001) between the symptoms and antibody levels. Workers with work-related respiratory symptoms showed a higher prevalence for the presence of specific IgE antibodies against workplace-specific enzymes than asymptomatic exposed workers (likelihood ratio 2.32, sensitivity 0.92, specificity 0.6)., Conclusions: Our data confirm the previous findings showing that genetically engineered enzymes are potent allergens eliciting immediate-type sensitisation. Owing to lack of commercial diagnostic tests, few of those exposed receive regular surveillance including biomonitoring with relevant specific IgE assays., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Purpose of Review: This review summarises the clinical knowledge of hypersensitivity pneumonitis in workers exposed to aerosols of metalworking fluid, reviewing published outbreaks and clinical cases., Recent Findings: Metalworking fluid exposure has become the commonest recognised cause of occupational hypersensitivity pneumonitis, having been rare before 2000. There are many possible agents in the metalworking fluid which may be the cause of disease including bacteria, mycobacteria, fungae, biocides, emulsifiers, reodorants and dissolved chrome and cobalt. Causes are likely to be different in different outbreaks. Mycobacteria growing in the metalworking fluid have generated immune responses in some workers, but their role in disease causation is not yet established. Many outbreaks have been identified in large workplaces using common sumps. It is not possible to prevent microbial contamination of metalworking fluids in use. Disease prevention should focus on stopping inhalation of aerosols, particularly by re-engineering to remove recirculation.

Introduction: Since 2000 a decline in the incidence of occupational asthma (OA) has been reported in the UK and Europe. We aimed to describe and account for trends in the incidence of OA in the West Midlands, UK using annual notification data from the SHIELD voluntary surveillance scheme over the period 1991-2011., Methods: All notifications to the SHIELD database between January 1991 and December 2011 were identified, along with patients' demographic data, occupations, causative agents and confirmatory tests. Annual notifications were scaled to give an annual count per million workers, giving a measure of incidence, and also standardised against those of bakers' asthma. Non-parametric analyses were undertaken between annual incidence and time (years) for common causative agents using (1) a negative binomial regression univariate model and (2) a logistic regression model calculating annual reporting ORs. A step-change analysis was used to examine time points at which there were marked reductions in incidence., Results: A decrease in annual incidence of OA was observed over the study period (incident rate ratio=0.945; 95% CI 0.933 to 0.957; p<0.0001), an effect that was lost after standardising for bakers' asthma. Decreases in incidence were seen for most common causative agents, with only cleaning product-related OA increasing over 21 years. Marked fall in incidence was seen in 2004 for isocyanates, and in 1995 for latex. Most notifications came from a regional specialist occupational lung disease unit, with notifications from other sites falling from 16 cases/million workers/annum in 1995 to 0 in 2004., Conclusions: Reporter fatigue and increasing under-recognition of OA are both factors which contribute to the apparent fall in incidence of OA in the West Midlands. There is a future need for interventions that enable health professionals to identify potential cases of OA in the workplace and in healthcare settings., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Occupational asthma commonly results in work-related changes in serial peak expiratory flow (PEF) measurements. Whether alveolitis can result in similar changes is unknown., Aims: To identify differences and similarities of serial PEF between workers with occupational alveolitis and asthma seen during an outbreak investigation in a factory with metal-working fluid exposure., Methods: Workers with respiratory symptoms and rest-day improvement were identified by questionnaire. Each was asked to measure PEF 8 times daily for 4 weeks at home and work. Alveolitis was subsequently diagnosed from a validated scoring system including radiological changes, carbon monoxide diffusing capacity, bronchoalveolar lavage and biopsy results. Occupational asthma was confirmed with a positive Oasys score >2.5 and a mean rest-work PEF >16 l/min from serial 2-hourly PEF measurements. The Oasys PEF plotter calculated differences between rest and workdays for mean PEF, diurnal variation and the scores were used to confirm an occupational effect (Oasys, area between curve and time point). Records were compared between the alveolitis group and the group with occupational asthma without alveolitis., Results: Forty workers with occupational asthma and 16 with alveolitis had indistinguishable PEF changes on workdays in terms of magnitude (median reduction 18.5 and 16.1 l/min, respectively) and diurnal variation. Immediate reactions were more common with occupational asthma and late reactions more common with alveolitis., Conclusions: PEF responses to metal-working fluid aerosols do not distinguish occupational asthma from alveolitis except in timing. They can be used to identify the workplace as the cause of asthma and also alveolitis., (© The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Introduction: Long delays from symptom onset to the diagnosis of occupational asthma have been reported in the UK, Europe and Canada and workers are often reluctant to seek medical help or workplace solutions for their symptoms. Reducing this delay could improve workers' quality of life, and reduce the societal cost of occupational asthma. This study aimed to explore reasons behind such delays., Methods: A purposive sample of 20 individuals diagnosed with, or under investigation for, occupational asthma (median age = 52; 70% male; 80% white British) undertook a single semi-structured interview. Interviews were transcribed verbatim and thematic analysis was undertaken in order to explore health beliefs and identify barriers to diagnosis., Results: Four themes were identified: (1) workers' understanding of symptoms, (2) working relationships, (3) workers' course of action and (4) workers' negotiation with healthcare professionals. Understanding of symptoms varied between individuals, from a lack of insight into the onset, pattern and nature of symptoms, through to misunderstanding of what they represented, or ignorance of the existence of asthma as a disease entity. Workers described reluctance to discuss health issues with managers and peers, through fear of job loss and a perceived lack of ability to find a solution. The evolution of workers' understanding depended upon how actively they looked to define symptoms or seek a solution. Proactive workers were motivated to seek authoritative help and negotiate inadequate healthcare encounters with GPs., Conclusion: Understanding workers' health beliefs will enable policy makers and clinicians to develop better workplace interventions that may aid diagnosis and reduce delay in identifying occupational asthma., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: This study used data from a large UK outbreak investigation, to develop and validate a new case definition for hypersensitivity pneumonitis due to metalworking fluid exposure (MWF-HP)., Methods: The clinical data from all workers with suspected MWF-HP were reviewed by an experienced panel of clinicians. A new MWF-HP Score was then developed to match the "gold standard" clinical opinion as closely as possible, using standard diagnostic criteria that were relatively weighted by their positive predictive value., Results: The new case definition was reproducible, and agreed with expert panel opinion in 30/37 cases. This level of agreement was greater than with any of the three previously utilized case definitions (agreement in 16-24 cases). Where it was possible to calculate, the MWF-HP Score also performed well when applied to 50 unrelated MWF-HP cases., Conclusions: The MWF-HP Score offers a new case definition for use in future outbreaks., (© 2014 The Authors. American Journal of Industrial Medicine Published by Wiley Periodicals, Inc.)

Background: Cobalt asthma has previously been described in cobalt production workers, diamond polishers and glassware manufacturers., Aims: To describe a case series of occupational asthma (OA) due to cobalt, identified at the Birmingham Heartlands Occupational Lung Disease Unit, West Midlands, UK., Methods: Cases of cobalt asthma from a West Midlands' manufacturer of automotive engine valves, diagnosed between 1996 and 2005, were identified from the SHIELD database of OA. Case note data on demographics, employment status, asthma symptoms and diagnostic tests, including spirometry, peak expiratory flow (PEF) measurements, skin prick testing (SPT) and specific inhalational challenge (SIC) tests to cobalt chloride, were gathered, and descriptive statistics used to illustrate the data., Results: The natural history of presentations has been described in detail, as well as a case study of one of the affected workers. Fourteen metalworkers (86% male; mean age 44.9 years) were diagnosed with cobalt asthma between 1996 and 2005. Workers were principally stellite grinders, stellite welders or machine setter-operators. All workers had positive Occupational Asthma SYStem analyses of serial PEF measurements, and sensitization to cobalt chloride was demonstrated in nine workers, by SPT or SIC., Conclusions: We have described a series of 14 workers with cobalt asthma from the automotive manufacturing industry, with objective evidence for sensitization. Health care workers should remain vigilant for cobalt asthma in the automotive manufacturing industry., (© The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

This consensus statement provides practical recommendations for specific inhalation challenge (SIC) in the diagnosis of occupational asthma. They are derived from a systematic literature search, a census of active European centres, a Delphi conference and expert consensus. This article details each step of a SIC, including safety requirements, techniques for delivering agents, and methods for assessing and interpreting bronchial responses. The limitations of the procedure are also discussed. Testing should only be carried out in hospitals where physicians and healthcare professionals have appropriate expertise. Tests should always include a control challenge, a gradual increase of exposure to the suspected agent, and close monitoring of the patient during the challenge and for at least 6 h afterwards. In expert centres, excessive reactions provoked by SIC are rare. A positive response is defined by a fall in forced expiratory volume in 1 s ≥ 15% from baseline. Equivocal reactions can sometimes be clarified by finding changes in nonspecific bronchial responsiveness, sputum eosinophils or exhaled nitric oxide. The sensitivity and specificity of SIC are high but not easily quantified, as the method is usually used as the reference standard for the diagnosis of occupational asthma., (©ERS 2014.)

Background: There is a disproportionately high number of cases of work-related asthma occurring in health care occupations due to agents such as glutaraldehyde, latex and cleaning products., Aims: To understand the causes and measure trends over time of occupational asthma (OA) in health care workers (HCWs)., Methods: We reviewed OA notifications from the Midland Thoracic Society's Surveillance Scheme of Occupational Asthma (SHIELD) database in the West Midlands, UK, from 1991 to 2011 and gathered data on occupation, causative agent and annual number of notifications., Results: There were 182 cases of OA in HCWs (median annual notifications = 7; interquartile range [IQR] = 5-11), representing 5-19% of annual SHIELD notifications. The modal annual notification was 20 (in 1996); notifications have declined since then, in line with total SHIELD notifications. The majority of cases (136; 75%) occurred in nursing, operating theatre, endoscopy and radiology staff. The most frequently implicated agents were glutaraldehyde (n = 69), latex (n = 47) and cleaning products (n = 27), accounting for 79% of the 182 cases. Cleaning product-related OA was an emerging cause with 22 cases after 2001 and only 5 cases between 1991 and 2000., Conclusions: Control measures within the UK National Health Service have seen a decline in OA in HCWs due to latex and glutaraldehyde, though OA remains a problem amongst HCWs exposed to cleaning products. Continuing efforts are required to limit the number of cases in this employment sector.

Background: Work-related asthma (WRA) is a major cause of respiratory disease in modern societies. The diagnosis and consequently an opportunity for prevention are often missed in practice., Methods: Based on recent studies and systematic reviews of the literature methods for detection of WRA and identification of specific causes of allergic WRA are discussed., Results and Conclusions: All workers should be asked whether symptoms improve on days away from work or on holidays. Positive answers should lead to further investigation. Spirometry and non-specific bronchial responsiveness should be measured, but carefully performed and validly analysed serial peak expiratory flow or forced expiratory volume in one second (FEV1) measurements are more specific and confirm occupational asthma in about 82% of those still exposed to the causative agent. Skin prick testing or specific immunoglobulin E assays are useful to document allergy to high molecular weight allergens. Specific inhalational challenge tests come closest to a gold standard test, but lack standardisation, availability and sensitivity. Supervised workplace challenges can be used when specific challenges are unavailable or the results non-diagnostic, but methodology lacks standardisation. Finally, if the diagnosis remains unclear a follow-up with serial measurements of FEV1 and non-specific bronchial hyperresponsiveness should detect those likely to develop permanent impairment from their occupational exposures.

The role of bronchoalveolar lavage (BAL) in the assessment of interstitial lung disease (ILD) remains controversial. Previous studies have demonstrated that BAL cell differential is useful in predicting disease progression in many forms of ILD. We wished to investigate whether BAL had a similar use in predicting disease progression in asbestosis. 21 patients who had significant asbestos exposure, findings of UIP radiologically and BAL performed as part of their investigation were reviewed. There was a significant inverse correlation between percentage BAL neutrophils and percentage predicted DLCO at diagnosis (n=21; P=0.02; r(2)=(-)0.25; CI, (-)0.77(-)0.08), but not with DLCO decline over 1 year. Unlike previous reports in IPF, BAL cell differential is not predictive of decline in classic asbestosis with a UIP pattern and its routine use in this cohort of patients provides little if any additional benefit.

Rationale and Objectives: Obliterative bronchiolitis (OB) is a rare disease with a small number of established occupational aetiologies. We describe a case series of severe OB in workers making glass-reinforced plastics., Methods: Workplace exposures were the likely cause after the independent diagnosis of OB in two workers laying up the fibreglass hulls of yachts; the second worker took over the job of the first after he left following a lung transplant. Presentation of these two cases at international meetings led to others identifying similar workers., Main Results: We identified six workers with good evidence of OB. All were involved in preparing fibreglass with styrene resins, five as boat builders laying up fibreglass hulls and one during cooling-tower fabrication. The disease came on rapidly without unusual acute exposures. Two patients had lung transplants, while another died while waiting for one. Histology confirmed OB in the four with biopsies/post-mortem examinations or explanted lungs., Conclusions: A rare, potentially fatal disease occurring in six workers laying up fibreglass with styrene resins from five different worksites suggests that work exposures were the cause of their OB. The precise agent responsible awaits identification.

Background: Five metal turners employed by an aerospace manufacturer presented to the Birmingham Chest Clinic occupational lung disease unit. Four cases of occupational asthma (OA) due to chromium salt (3) and cobalt (1) were diagnosed by serial peak-expiratory flow measurements and specific inhalation challenge testing., Aims: To measure the extent of the outbreak and to provide epidemiological data to ascertain the aetiology., Methods: Participants answered a detailed, self-administered questionnaire, designed to detect occupational lung disease. Urine chromium and cobalt excretion, spirometry and exhaled nitric oxide measurements were taken. Those with possible, probable or definite non-OA or OA, after questionnaire, were invited to undertake two-hourly peak flow measurements and received specialist follow-up., Results: A total of 62 workers (95% of workforce) participated. Sixty-one per cent of employees were working in higher metalworking fluid (MWF) exposure areas. Ninety per cent of workers had urinary chromium excretion indicating occupational exposure. Sixty-six per cent of workers reported active respiratory symptoms, although there were no significant differences between exposure groups. Two further workers with probable OA were identified and had significantly higher urinary chromium and cobalt concentration than asymptomatic controls. Eighteen cases of occupational rhinitis (OR) were identified, with significantly raised urinary chromium concentration compared with asymptomatic controls., Conclusions: Chromium salt and cobalt can be responsible for OA and OR in workers exposed to MWF aerosols. Onset of symptoms in those with positive specific challenges followed change in MWF brand. Workers with OA had increased urinary concentrations of chromium and cobalt, and those with OR had increased urinary concentrations of chromium.