User:Saltrabook/Diagnostic Guidelines/Occupational Asthma

OCCUPATIONAL ASTHMA

Asthma is ‘occupational’ when it has been caused directly by an agent encountered at work – usually an airborne allergen. Repeated inhalation causes a respiratory hypersensitivity in some people, which is similar to ordinary allergic asthma in response to house dust mites or cats. Risky jobs Around 400 workplace agents have been reported to cause occupational asthma. Fortunately, most of these are rarely encountered and about three-quarters of all the cases in the UK are attributable to only a handful of exposures https://en.wikipedia.org/wiki/Occupational_asthma

Identifying occupational asthma

Ask every asthma patient of working age what they do for a living, with details. ‘I work for a supermarket’ isn’t adequate. It is also worth asking whether their symptoms are better when they are not at work and whether there is anything at work that sets symptoms off. Be especially alert to patients whose asthma has begun – or relapsed – shortly after starting a new job. Also, remember that occupational asthma is often accompanied by occupational rhinitis. Patients may attribute this to hayfever or a cold. See the box, right, for a case history.

Implications of a diagnosis for the patient

It is usually recommended that patients with occupational asthma avoid further exposure to the causative agent. Even very small exposures will provoke continuing symptoms, and so it is often difficult for patients to avoid the asthmagen while remaining in the job. For example, wearing a face mask is seldom sufficient even if it is tolerable. Large, wellrun firms will attempt to find the employee alternative work in the organisation. Where this is impossible, as is often the case with smaller companies, your patient is likely to lose their job.

For the employer

Employers are required by law to report cases of occupational asthma in their workforce to the Health and Safety Executive. This usually results in a formal, external inspection that can be expensive for a business. And the patient will lose any anonymity they might have had, potentially making it an uncomfortable experience. For all of these reasons, it is easy to see why a false positive diagnosis of occupational asthma is potentially disastrous.