Diagnostic failures in occupational asthma
By Emma Wilkinson
Many key tests needed to diagnose occupational asthma are only available in specialist centres, which patients may have to travel up to 100 miles to access, according to UK researchers.
A survey of hospital respiratory departments has highlighted that although basic spirometry tests are available for those referred by GPs, facilities for an accurate diagnosis of occupational disease are lacking.
The team from the Centre for Workplace Health said inaccurate diagnoses were damaging for the patient – either by keeping them in an unhealthy environment or unnecessarily removing them from work.
An estimated one in 10 cases of adult asthma is a direct result of workplace exposure – for example, to flour dust in bakeries, or isocyanate paint spray.
The survey of 100 UK respiratory units found that two-thirds of consultants had seen a case of occupational asthma in the past month.
Of a list of tests deemed essential for diagnosis, only 15% of departments had software to analyse serial peak flow records and non-specific airway responsiveness assessment was only available in half the departments.
Only two departments questioned were able to offer a workplace or in-hospital specific airway challenge.
Tertiary centres where the tests could be done were between four and 100 miles away.
Dr Chris Barber, study leader and honorary consultant in respiratory health at the Royal Hallamshire Hospital in Sheffield, said GPs should be asking all adult asthma patients about workplace exposure but said there was great variation in access to specialists.
‘It's a very important diagnosis to get right – you don't want to miss it,' he said.
‘We want GPs to ask adults who have developed asthma or who have worsening symptoms if their symptoms are worse at work and ideally they would get referred to secondary care.'
New guidance on investigating occupational asthma is due to be published soon and Dr Barber will also be issuing an e-learning tool for GPs.
But Dr Hilary Pinnock, a GP in Whitstable, Kent, and member of the General Practice Airways Group, said hospital services would improve once GPs started driving demand through practice-based commissioning.
‘If we do wake up to it a bit more there will be more of a push for adequate facilities and we have the drivers through practice-based commissioning to encourage that.'
The research was published online by Occupational Medicine.Essential tests for occupational asthmaEssential tests for occupational asthma Essential tests for occupational asthma
• Software to analyse peak serial flow and non-specific airway responsiveness
• Workplace or in-hospital specific airway challenge