Reference

Gautrin D, Ghezzo H, InfanteRivard C et al, Natural history of sensitisation, symptoms and occupational diseases in apprentices exposed to laboratory animals, Eur Respir J, 2001;17:904-908,

BOHRF Original Authors' Main Conclusions

The original authors' main conclusions are taken from Abstract, Results and Discussion. They are decided upon by the authors of the BOHRF occupational asthma guidelines and form part of the guidelines.

Study describes the time-course of the incidence of work-related symptoms, skin reactivity and occupational rhino-conjunctivitis (RC) and occupational asthma and assesses the predictive value of skin testing and RC symptoms in apprentices exposed to laboratory animals, in a 3-4-yr programme. Apprentices at five institutions were assessed prospectively with questionnaire, skin-testing with animal-derived allergens, spirometry and airway responsiveness. Depending on the school, students were seen 8, 20, 32 and 44 months after starting the programme. The positive predictive values (PPVs) of skin reactivity to work-related allergens for the development of work-related RC and respiratory symptoms were 30% and 9.0%, respectively, while the PPV of work-related RC for the development of occupational asthma was 11.4%. Sensitisation, symptoms and diseases occurred maximally in the first 2-3 yrs after starting exposure to laboratory animals. Skin reactivity to work-related allergens and rhino-conjunctivitis symptoms have low positive predictive values.

BOHRF Associated Evidence Statements

The BOHRF occupational asthma guidelines state that this reference is associated with the following evidence statements

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Atopy increases the risk of developing occupational asthma caused by exposure to many high molecular weight agents that induce the production of specific IgE antibodies.

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Occupational rhinitis and occupational asthma frequently occur as co-morbid conditions in IgE associated occupational asthma.

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Rhino-conjunctivitis is more likely to appear before the onset of IgE associated occupational asthma.

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Sensitisation and occupational asthma are most likely to develop in the first years of exposure for workers exposed to enzymes, complex platinum salts, isocyanates and laboratory animal allergens.