Use of induced sputum in the investigation of occupational asthma

The diagnosis of occupational asthma relies mainly on the demonstration of changes in airway calibre and airway responsiveness after exposure to occupational agents in the laboratory or at the workplace. However, spirometry or peak expiratory flow measurements may be open to misinterpretation when they are not performed optimally. As in non-occupational asthma, airway inflammation is one of the main characteristics of occupational asthma. Induced sputum, a non invasive method to assess airway inflammation, has been successfully used in the management of asthma. This article reviews the studies that have investigated and characterized the changes in sputum cell counts occurring in subjects with occupational asthma after exposure to occupational agents in the laboratory or at the workplace in order to assess the place of induced sputum in the investigation of occupational asthma. It also reviews the use of induced sputum during the follow-up of workers with occupational asthma after removal from exposure. This article also describes a new condition identified thanks to the use of induced sputum : occupational eosinophilic bronchitis. In conclusion, induced sputum is a useful tool in the investigation of occupational asthma. Its use on a regular basis in the investigation of occupational asthma also allows for the possibility of diagnosis of overlooked conditions such as occupational eosinophilic bronchitis. Its role in the surveillance of workers at risk to develop occupational asthma remains to be determined.     

Epidemiology in protection and prevention against environmental mutagens/carcinogens Examples from occupational medicine

Subjects occupationally exposed to potential mutagens/carcinogens represent the most suitable groups for epidemiological studies aimed at assessing the risk for the individual or the offspring. Several cancer risks to humans have been detected by epidemiological studies performed in occupational settings. Cancer epidemiology studies have been able (a) to identify specific occupations or agents associated with the risk; (b) to verify the results of experimental studies; (c) to test the effectiveness of changes in production or preventive measures in decreasing risks. Reproductive epidemiology has suggested a risk of spontaneous abortions or of malformation in the offspring of workers exposed to some chemicals or occupations, but data are often conflicting due to methodological problems. With the aim of early assessment of risk in mind, the epidemiological use of indicators of exposure or of the early effect of exposure to genotoxic agents is increasingly applied to occupational groups. Cytological monitoring of subjects at risk of occupational cancer of lung or bladder is carried out mainly to diagnose precancerous lesions of target tissues. Cytogenetic methods (chromosome aberrations, SCE, micronuclei) in somatic cells provide a means for detecting early effects of occupational exposure to known or potential mutagens/carcinogens in selected groups of individuals, but their significance is widely debated. Monitoring of urinary mutagenicity, as applied in nurses handling cytostatic drugs, is an example of how an indicator of exposure to genotoxins can be used to evaluate the impact of preventive measures. Among the perspectives, biochemical epidemiology seems to be promising in detecting individuals genetically susceptible to cancer.     

Diagnosing occupational asthma: insight from induced sputum

The diagnosis of occupational asthma needs to be made objectively using as many criteria as possible. The latter include laboratory exposure tests with occupational agent(s), which are only available in specialized centers. Another approach is to monitor peak expiratory flow (PEF) and (or) methacholine airway responsiveness during periods at work and away from work. However, these measurements are open to misinterpretation when they are not optimally performed. Airway inflammation is one of the main characteristics of asthma. Induced sputum, a non-invasive method to assess airway inflammation, has been successfully used in the management of asthma. However, airway inflammation is seldom assessed during the investigation of occupational asthma. This article reviews the studies that have investigated and characterized the changes in sputum cell counts occurring in subjects with occupational asthma after exposure to occupational agents in the laboratory, or at the workplace to assess to place of induced sputum in the investigation of occupational asthma.     

A pilot study about infertile men’s awareness of their reprotoxic exposures and the intervention of occupational medicine to assess them

Background

Male infertility related to professional reprotoxic exposure has been assessed in several studies. Collaboration between occupational physicians and patients can yield information about the preventive measures that can be taken to avoid such exposure. The use of preventive measures is determined by the collaboration between reproductive medicine and occupational medicine and also by the patient’s awareness of reprotoxic occupational exposures. Our andrology laboratory developed a systematic environmental interview that an occupational physician administers before semen analysis to assess patients’ occupational reprotoxic chemical and physical exposures. This observational prospective study evaluated patients’ feelings regarding this interview. The main outcome measure was the participants’ score to determine their general reprotoxicant knowledge. The study also evaluated the patients’ satisfaction about the interview with occupational physician and their attitude about reproductive toxicants.

Results

The mean score for general knowledge of reprotoxicants was 9.6?±?2.7/16. The most frequently underestimated reprotoxic factor was excessive heat (34.7 % correct responses). In cases of semen parameter abnormalities AND recognized occupational reprotoxic exposure, 63.2 % of the patients said they would use individual protective devices, and 55.1 % said they would temporarily adapt their workstation. Regarding the interview with the laboratory’s occupational physician, 80.7 % considered it moderately or very useful. Of the interviewed patients, 46.2 % reported having changed their living habits 2 months after the interview, and 88.5 % were satisfied or very satisfied with the care they received. All of the respondents said it would be useful to extend the interview to include their wives.

Conclusions

The data suggest that patients’ knowledge about reprotoxic exposures can be improved, particularly knowledge related to physical exposure. The vast majority of patients were satisfied with the introduction of this new collaboration between reproductive and occupational medicine.

     

A Report on the Evaluation of Exhibits—Mediscope 1961

Thirty-two educational exhibits presented by the Ontario Medical Association at the 1961 Canadian National Exhibition in Toronto in the exhibit known as “Mediscope 1961” were subjected to an evaluative study. Applying the criteria of educational effectiveness to each exhibit, relative ratings for each exhibit as well as the educational value of Mediscope as a whole were obtained. Quantitative data indicated that this venture in health education was a highly successful endeavour, as 80% of the criteria for educational effectiveness were met by all exhibits. In addition, the study emphasized the potential of educational exhibits in the field of public health education as well as education of specific groups.The desirability of similar studies is stressed. In addition to quantitative assessment of educational exhibits, such studies would disclose the impact of health information on the attitudes and behavioural changes on the part of the public.     

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.     

Modeling the impact of genetic screening technologies on healthcare: theoretical model for asthma in children

BACKGROUND AND OBJECTIVE: This study focuses on the potential impact of genetic screening technologies on healthcare. Genetic screening for asthma in children was chosen as a case study to explore the cost effectiveness of applying early genetic screening to infants, and preventive treatment to the population at risk. Early intervention could prevent progression and facilitate clinical management of the disease. From the elite group of genetic markers that have been associated with asthma-related phenotypes, ADAM33 was the first published candidate gene detected by a positional cloning approach, marking the entry of asthma research into the genomic era. The model was, therefore, initially set for an ex ante analysis of the cost effectiveness of applying the preventive program to an infant population at risk, i.e. infants presenting wheezing episodes during the first year of life, and the ADAM33 ST+7 genetic marker, with the idea of expanding to further markers and their combinations lat a later date. METHODS: In accordance with the US National Heart, Lung, and Blood Institute, four categories of asthma were considered. A Markov model was constructed, consisting of six mutually exclusive disease states (including healthy and dead states) with a simulation horizon of 100 years and a cycle length of 1 year. We define a scenario where early genetic screening was applied to infants presenting wheezing episodes during the first year of life and a preventive treatment to those children within this group who tested positive for selected ADAM33 polymorphism (ST+7). The cost-effectiveness analysis was performed from the third-party payer and patient perspective after year 6. We applied our model to a hypothetical cohort of 100 European infants. RESULTS: The number of quality-adjusted life-years (QALYs) gained during the 6 years was 1.483, and the incremental cost-effectiveness ratio per QALY gained was euro 10,100/QALY. A sensitivity analysis was carried out that varied the discount rate and cost of genetic testing, and considered two different transition matrices for the preventive program. Three main conclusions were drawn from the sensitivity analysis. Firstly, if the discount rate for both cost and health outcomes is increased by 2%, the cost effectiveness of the preventive program does not vary significantly. Discounting costs and benefits at 5%, the preventive program appears cost effective (euro 11,100/QALY). Secondly, if the cost of genetic testing is increased to euro 100, the cost effectiveness of the preventive program remains within the limits of cost effectiveness. Thirdly, the cost of genetic screening, together with transition probabilities between health states, will determine the cost effectiveness of applying a preventive program based on genetic information. CONCLUSIONS: Preventive treatment based on an early genetic screening of those children who present wheezing episodes during the first year of life, with treatment applied to those who test positive for the asthma-associated genetic marker ADAM33 ST+7, is theoretically cost effective. The model is a valuable tool for the ex ante assessment of the cost effectiveness of preventive schemes based on genetic screening. The value of modeling prior to clinical trials lies in informing study design and setting priorities for future research.     

Consideration on a limit for lifetime occupational radiation exposure

Annual dose limits in occupational radiation exposure are merely a secondary constraint in addition to the primary rule of dose reduction and justification. The limits may, therefore, be reached only in rare, special cases. However, in principle, there might be cases in which the annual limit is continuously exhausted throughout a working life; a high total dose of 0.8 Sv could then be reached. In view of this possibility, there have been considerations of an added restriction by limiting the lifetime occupational dose to 0.4 Sv. The implications of such lifetime doses are considered, and it is shown that an exposure up to the maximum of 0.8 Sv will lead to the need for compensation, if a leukaemia were to occur in the exposed worker. A lifetime dose of 0.4 Sv equally spread over a working life will not lead to the critical value of the probability of causation in excess of 0.5. Nevertheless, it could cause such critical values when it is accumulated during shorter periods. More decisive than the probabilities of causation are, however, the absolute numbers of excess cases of leukaemia due to the occupational exposure. It is seen that less than one excess case would be expected if a group of 100 workers were all exposed to the maximum of 0.8 Sv. Since lifetime doses of 0.8 or 0.4 Sv will be accumulated in very few cases and only with special justification, there appears to be little need to introduce a further limit of lifetime exposure in addition to the current annual limit. Received: 15 November 1997 / Accepted in revised form: 1 April 1998     

Medical surveillance of allergy in laboratory animal handlers

Allergic disease is a serious occupational health concern for individuals who have contact with laboratory animals. The principal respiratory symptoms include allergic rhinitis, conjunctivitis, and asthma. Urticaria (" hives") is the most common skin manifestation. The overall prevalence of allergic disease among laboratory animal handlers is about 23%, and respiratory allergy is much more common than skin allergy. Various studies have found annual incidence rates ranging from 2% to 12%. Prevention of animal allergy depends on control of allergenic material in the work environment. Personal protective equipment such as air filtering respirators should be used in addition to the other exposure control technologies where conditions require. Pre-placement evaluation and periodic medical surveillance of workers are important pieces of the overall occupational health program. The emphasis of these medical evaluations should be on counseling and early disease detection. The article gives recommendations for the content of the medical evaluations.     

Occupational cancer: experience in Ontario.

This paper reviews the experience of the Workmen''s Compensation Board of Ontario in identifying cases of cancer that could be attributed to occupational hazards. Worker''s claims for compensation are allowed if there is reasonable medical evidence that their cancer was caused by exposure to risk factors associated with their occupation. Details of the types of cancer associated with specific carcinogens or fields of employment are discussed. About 50% of the cases were related to exposure in particular industrial operations that functioned for relatively brief periods. The number of deaths from cancer identified as being caused by occupational factors is compared with the total for cancer from all causes in Ontario during the period 1971 through 1975. Although all workers eligible for compensation may not have been identified, the data suggest that less than 1% of cancer is presently caused by occupational factors.     

Breaking new ground: challenging existing asthma guidelines

Background

While we have international guidelines and various national guidelines for asthma diagnosis and management, asthma remains poorly controlled in many children and adults. In this paper we review the limitations of current asthma guidelines and describe important issues and remaining questions regarding asthma guidelines for use, particularly in primary care.

Discussion

Clinical practice guidelines based on evidence from randomized controlled trials are considered the most rigorous and accurate. Current evidence-based guidelines are written predominantly from the perspective of the patient with a clear-cut asthma diagnosis, however, and tend not to consider the heterogeneity of asthma or to accommodate individual patient variations in response to treatment or their needs, differences in practice settings, or local differences in availability and cost of therapies. The results of randomized controlled trials, which are designed to establish efficacy of treatment under ideal conditions, may not apply to 'real-world' clinical practice, where patients are unselected, monitoring is less frequent, and effectiveness – the benefit of treatment in routine clinical practice – is the most relevant outcome. Moreover, most guidelines see asthma in isolation rather than considering other factors that may impact on asthma and response to asthma therapy, particularly age, allergic rhinitis, cigarette smoking, adherence, and genetic factors. When these links are recognized, guidelines rarely provide practical recommendations for treatment in these scenarios. Finally, there is some evidence that general practitioners are not convinced of the applicability of asthma guidelines to their practice settings, especially when those writing the guidelines principally work in specialist practice.

Conclusion

Developing country-specific guidelines or, ideally, local guidelines could provide more practical solutions for asthma care and could account for regional factors that influence patient choice and adherence to therapy. Pragmatic clinical trials and well-designed observational trials are needed in addition to randomized controlled trials to assess real-world effectiveness of therapies, and such evidence needs also to be considered by guideline writers. Finally, practical tools to facilitate the diagnosis and assessment of asthma and factors responsible for poor control, such as associated allergic rhinitis, limited adherence, and smoking behavior, are needed to supplement treatment information provided in clinical practice guidelines for asthma.

     

Known occupational carcinogens and their significance.

Although rates of occupational cancer can be excessive in certain industries, less than 5% of all cancers seem attributable to exposure to carcinogens in the workplace. For example, workers in hard-rock mining and the woodworking industries are at increased risk; cigarette smoking has a synergistic effect. There is conclusive evidence of carcinogenicity for fewer than 20 substances, including asbestos, arsenic, chromium, nickel, cadmium, radon, several aromatic hydrocarbons and certain herbicides. Most of the hundreds of organic compounds known to be mutagenic in in-vitro tests have not been shown to be carcinogenic in epidemiologic studies. Both laboratory and epidemiologic approaches, however, can identify probable causes of cancer and permit the application of effective preventive measures. In addition, it is still possible for the alert individual clinician to make the initial discovery of an occupational hazard.     

Assessment and treatment of laboratory animal allergy

Laboratory animal allergy (LAA) is a form of occupational sensitivity affecting up to one third or more of exposed workers. Symptoms involve the eyes, nose, skin, and lower respiratory tract. Asthma may develop in 20 to 30% of sensitized individuals. An occupational medical history is the primary tool if a diagnosis of LAA is suspected. The diagnosis is confirmed by demonstrating the presence of immunoglobulin E antibodies to laboratory animal allergens by skin testing or in vitro assays. If laboratory animal allergen-induced asthma is suspected, measurements of lung function are necessary for confirmation and assessing the degree of impairment. One approach to the problem is presented in this article. For individuals with LAA, avoidance of exposure is the primary treatment. For individuals who continue to work in the environment, pharmacological treatment of their symptoms may be necessary. Methods to prevent the development of LAA are also discussed.     

Banding carcinogenic risks in developed countries: A procedural basis for qualitative assessment

Readily achieved comparative assessment of carcinogenic risks consequent upon environmental exposures may increase understanding and contribute to cancer prevention. Procedures for hazard identification and quantitative risk assessment are established, but limited when addressing novel exposures to previously known carcinogens or any exposure to agents having only suspected carcinogenic activity. To complement other means of data evaluation, a procedure for qualitative assessment of carcinogenic risk is described. This involves categorizing the relevant carcinogen and circumstances under which exposure occurs. The categories for carcinogens are those used for hazard identification and involve whether the agent is (1) a recognized carcinogen for humans; (2) probably or (3) possibly carcinogenic for humans; (4) characterized by inadequate evidence of carcinogenicity; or (5) lacking carcinogenicity. Exposure is categorized by whether it is one which (1) establishes the agent as a recognized carcinogen; (2) is taken into account in establishing carcinogenicity status; (3) is distinct from those providing clearest evidence of carcinogenicity; (4) is not characterized in relation to carcinogenicity; or (5) involves an exposure in which absence of carcinogenic outcome is observed. These two categories of evidence allow the risk inherent in a situation to be banded as indicative of a proven, likely, inferred, unknown or unlikely carcinogenic outcome, and further characterized using sub-bands. The procedure has been applied to about fifty situations. For recognized carcinogens, including asbestos and polycyclic aromatic hydrocarbons, risks consequent upon occupational exposure, the impact of point source pollution, residence near contaminated sites and general environmental exposure are allocated across the proven band and a likely sub-band. For solvents, pesticides and other compounds having less clearly established carcinogenicity, impact on residents living near a production site, or near earlier related industrial activity is allocated to certain inferred sub-bands. Unknown carcinogenic outcome, which identifies exposure to an agent with inadequate evidence of carcinogenicity rather than being indicative of equivocal or negative data in any context, indicates both the impact of certain pollutants and user-exposure to some consumer products. Situations allocated to the unlikely risk band principally involve certain consumer products. Overall, such risk assessment may be of greatest worth in focusing community attention on proven causes of cancer and associated preventive measures.     

Occupational Skin Diseases in the San Francisco Bay Area

From answers by one-third of the practicing dermatologists in the San Francisco Bay Area to a questionnaire on occupational skin diseases, contact dermatitis due to irritants and sensitizers was found to rank first. Poison oak, which is the leading reported cause on “Doctor''s First Report of Work Injury” received by the California Department of Industrial Relations, was sixth on the list of the survey, trailing solvents, cleansing agents, petroleum products and epoxy resins. A history of atopic dermatitis was often noted in current cases of occupational diseases of the skin.Avoidance of exposure or limiting the contact with pathogenic substances—through engineering changes, observation of working conditions by physicians, education of workers—appeared to be the best preventive measures.     

Occupational injuries,illness affect 1 in 13 Canadians.

One in every 13 Canadian workers has experienced a work-related illness or injury, federal data indicate. Occupational-health clinics in Ontario report a growing number of cases of sick-building syndrome, repetitive-strain injury, asthma and chemical exposure, as well as injuries related to the use of construction equipment. In the past the medical profession assumed that men incurred most work-related injuries, but today, says an occupational-health specialist, "work-related illness and injuries are just as likely to happen to women or to white-collar professionals."     

Evaluation of the returned traveler.

Recognition of clinical syndromes in returned travelers is an important part of providing care to international travelers. The first step is to take a history with attention to pre-travel preventive measures, the patient's itinerary, and potential exposure to infectious agents. The patient should then be examined to document physical signs, such as fever, rash, or hepatosplenomegaly, and to have basic laboratory data obtained. This evaluation will provide most physicians with the necessary information to generate a differential diagnosis. Each diagnosis should be matched against the incubation period of the disease, the geographic location of illness, the frequency of illness in returned travelers, and the pre-travel preventive measures. Careful attention to these aspects of patient care should result in the appropriate diagnosis and therapeutic intervention for the ill returned traveler.     

Occupational diseases, working ability and employment status in the working population of Croatia

The paper gives insight into the working ability and employment status of workers with recognized occupational diseases in Croatia. The analysis based on working ability data from 212 workers shows that 12 (5.5%) workers have general disability for work, 75 (35.5%) occupational disability for work, 98 (46.4%) danger of disability onset, 13 (6%) no disability and 14 (6.5%) are sent for further medical treatment. The highest frequency of occupational diseases is in the group of workers with 41-50 years of age, in the category of 20-24 exposure years. Official data imply that the incidence rate of occupational diseases in Croatia is 4 times lower than in European Union. Such a low incidence rate derives from problems in the system of healthcare and health insurance, and also from problems in the system of monitoring and registering of occupational diseases.     

Early education and health outcomes of a 2001 U.S. Birth Cohort

This paper looks at health outcomes, health behaviors, and health screening with respect to participation in Early Childhood Care and Education. With information on health status at multiple periods in time, we are able to look at whether healthier children select into early childhood education (as measured by center-based preschool care and Head Start), as well as whether early childhood education has immediate and near-term effects on a range of health status measures. There is some evidence that child obesity is ameliorated by participation in center-based preschool or Head Start and this finding is supported by clear evidence of improved nutrition and increased levels of health screening. Effects on other health outcomes such as asthma, ear infections, and respiratory problems may be partially masked by unobserved heterogeneity.     

Healthcare Workers' Challenges in the Implementation of Tuberculosis Infection Prevention and Control Measures in Mozambique

Objective

Healthcare Workers (HCWs) have a higher frequency of TB exposure than the general population and have therefore an occupational TB risk that infection prevention and control (IPC) measures aim to reduce. HCWs are crucial in the implementation of these measures. The objective of the study was to investigate Mozambican HCWs'' perceptions of their occupational TB risk and the measures they report using to reduce this risk. In addition, we explored the challenges HCWs encounter while using these TBIPC measures.

Methods

Focus group discussion. Analysis according content method.

Participants

Four categories of HCWs: auxiliary workers, medical (doctors and clinical officers), nurses and TB program staff.

Results

HCWs are aware of their occupational TB risk and use various measures to reduce their risk of infection. HCWs find it challenging to employ measures that minimize such risks and a lack of clear guidelines contributes to these challenges. HCWs'' and patient behavior further complicate the use of TBIPC measures.

Conclusion

HCWs in Mozambique perceive a high occupational risk of TB infection. They report several challenges using measures to reduce this risk such as shortage of material, lack of clear guidelines, insufficient motivation and inadequate training. Robust training with motivational approaches, alongside supervision and support for HCWs could improve implementation of TBIPC measures. Healthcare management should address the areas for improvement that are beyond the individual HCW''s control.