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Denyse Gautrin

Publications and source records attributed to Denyse Gautrin.

7 recordsLinked to original sources

Occupational asthma.

PURPOSE OF REVIEW: The scientific literature on occupational asthma is steadily increasing and no longer only describes case reports with prevalence figures and limited physiopathologic and immunologic data. Prospective cohort studies are currently carried out with relevant incidence figures and risk factors. Genetic susceptibility is explored. New diagnostic means are described. Surveillance programs are conducted and preventive measures are proposed. RECENT FINDINGS: A relevant account was published on the respiratory consequences (irritant-induced asthma, a type of occupational asthma) of exposure of firefighters at the World Trade Center site. Glutathione-S-transferase appears to be an interesting susceptibility gene for occupational asthma as a result of isocyanates. Inflammation caused by neutrophils and not only by eosinophils is more often associated with occupational asthma. Examination of induced sputum and assessment of exhaled nitric oxide are becoming useful diagnostic tools. Cleaners are at increased risk of developing occupational asthma, although the causal agents are unknown. Surveillance programs currently combine strategies that aim to reduce exposure and identify cases early. SUMMARY: New scientific information provides better, accurate figures on the frequency of occupational asthma and on risk factors, proposes relevant diagnostic tools more directly related to the physiopathology of the disease, and suggests effective surveillance programs in high-risk workplaces.

Asthma↗

Chlorine-induced injury to the airways in mice.

Exposure to chlorine gas (Cl2) causes occupational asthma that we hypothesized occurs through the induction of airway inflammation and airway hyperresponsiveness by oxidative damage. Respiratory mechanics and airway responsiveness to methacholine were assessed in A/J mice 24 hours after a 5-minute exposure to 100, 200, 400, or 800 ppm Cl2 and 2 and 7 days after inhalation of 400 ppm Cl2. Airway responsiveness was higher 24 hours after 400 and 800 ppm Cl2. Responsiveness after inhalation of 400 ppm Cl2 returned to normal by 2 days but was again elevated at 7 days. Airway epithelial loss, patchy alveolar damage, proteinaceous exudates, and inflammatory cells within alveolar walls were observed in animals exposed to 800 ppm Cl2. Macrophages, granulocytes, epithelial cells, and nitrate/nitrite levels increased in lung lavage fluid. Increased inducible nitric oxide synthase expression and oxidation of lung proteins were observed. Epithelial cells and alveolar macrophages from mice exposed to 800 ppm Cl2 stained for 3-nitrotyrosine residues. Inhibition of inducible nitric oxide synthase with 1400W (1 mg/kg) abrogated the Cl2-induced changes in responsiveness. We conclude that chlorine exposure causes functional and pathological changes in the airways associated with oxidative stress. Inducible nitric oxide synthase is involved in the induction of changes in responsiveness to methacholine.

Administration, Inhalation↗

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

BACKGROUND: Exposure to laboratory animals often causes the appearance of immunologic sensitization and symptoms. OBJECTIVE: Our aim was to determine the incidence of occupational rhinoconjunctivitis and the timing of symptoms and their determinants in apprentices starting exposure to laboratory animals. METHODS: Data from 387 (92.8%) of 417 students entering career programs in animal health in 5 schools were kept for analysis. Questionnaires and skin prick tests with common and occupational inhalants were carried out on entry and at follow-up visits scheduled at 8, 20, 32, and 44 months, depending on the schools. Responsiveness to inhaled methacholine was assessed at entry. RESULTS: Ninety-three (24%) subjects showed incident occupational rhinoconjunctivitis symptoms, and 37 (9.6%) had symptoms combined with skin sensitization to an animal-derived allergen. Symptoms such as sneezing, rhinorrhea, and itchy eyes tended to develop early in the course of exposure. In two thirds of the subjects, symptoms persisted at subsequent visits. In a multivariate analysis the determinants of the appearance of rhinoconjunctivitis with or without allergic sensitization included sensitization to grass pollens (odds ratio [OR], 1.78; 95% CI, 0.99-3.19), as well as nasal (rhinorrhea in contact with dust: OR, 1.79; 95% CI, 1.05-3.05) and bronchial symptoms (chest tightness: OR, 3.31; 95% CI, 0.98-11.25; cough on exposure to strong odors: OR, 1.88; 95% CI, 0.98-3.59). CONCLUSION: The incidence of occupational rhinoconjunctivitis symptoms with or without immunologic sensitization is high in apprentices starting exposure to laboratory animals. Symptoms related to histamine release are common in the early course of exposure. Determinants include immunologic and target-organ susceptibility.

Adolescent↗

Time course of onset of sensitization to common and occupational inhalants in apprentices.

BACKGROUND: Incident sensitization to common allergens in the setting of sensitization to an occupational allergen has not been described. OBJECTIVE: Our aim was to determine the risk and timing of development of sensitization to common allergens in subjects with incident sensitization to a work-related allergen. METHODS: Data from a cohort of 769 apprentices in animal-health technology, pastry making, and dental hygiene were used. Skin prick tests to work-related allergens (laboratory animal, flour, and latex) and common allergens (mites, molds, pets, and pollen) were administered at baseline and at up to 3 subsequent annual visits. Risk ratios (RRs) and 95% CIs were calculated. RESULTS: Eighty-three subjects had sensitization to a work-related allergen. Four (4.8%) subjects became sensitized to common and then occupational allergens. Nine (10.8%) subjects had sensitization to a common allergen after sensitization to a work-related allergen. In 20 (24.1%) subjects new sensitizations to specific and common allergens were detected simultaneously. Fifty subjects remained free from new sensitization to occupational allergen during development of sensitization to common allergens. An increased risk of development of sensitization to molds (RR = 3.49) and pets (RR = 2.51) was found in subjects with incident sensitization to occupational allergens relative to the risk in subjects without sensitization. CONCLUSION: New sensitization to common aeroallergens is frequent in subjects not previously exposed to work-related allergens; it often occurs around the same time as sensitization to work-related agents. Subjects with new occupational sensitization are at a greater risk of development of sensitization to common aeroallergens than subjects without sensitization.

Administration, Inhalation↗

Socioeconomic status and utilization of health care services among asthmatic children.

We evaluated the relation between socioeconomic factors and hospitalization as well as emergency department (ED) visits among asthmatic children who had universal access to health care. Newly diagnosed asthmatic children 3-4 years of age were followed up for a period of 6 years. Information on hospitalization and ED visits was obtained by interviewing parents. Socioeconomic status (SES) was measured by paternal occupation, race, type of dwelling, and an index of crowding. After adjusting for asthma severity, logistic regression analysis showed that children with fathers in the economically least advantaged occupations were more likely to be hospitalized due to their asthma [father's occupation group 3 (FOG3), odds ratio (OR)=2.1, 95% confidence interval (95% CI)=0.2-19.8; father's occupation group 4 (FOG4), OR=13.9, 95% CI=1.1-181.4]. The probability of emergency department visits was not significantly different according to the studied variables. Emergency department visits were not influenced by SES variables, probably due to the absence offinancial barriers to access health care. However, SES differences in hospitalization may suggest differential management and/or treatment practices according to socioeconomic status at the emergency departments.

Adult↗

Persistence of airway responsiveness to occupational agents: what does it matter?

In the majority of workers with occupational asthma, the disease remains active even several years after removal from exposure or diminution of the levels of exposure to the causal agent. Only 25% or so normalize their lung function and their bronchial responsiveness to nonspecific agents. The aim of this review is to present recent findings illustrating the persistence of specific bronchial responsiveness and the associated factors in workers who apparently have recovered from occupational asthma. This subject is also examined from a socioeconomic perspective.

Asthma↗