Article Text

Download PDFPDF

Case based discussion
Lesson of the month: extrinsic allergic (bronchiolo)alveolitis and metal working fluids
  1. Paul Cullinan1,
  2. Eva D'Souza2,
  3. Rachel Tennant3,
  4. Chris Barber4
  1. 1Department of Occupational and Environmental Medicine, Imperial College (NHLI) and Royal Brompton Hospital, London, UK
  2. 2Health Management Limited, London, UK
  3. 3Department of Respiratory Medicine, Northwick Park Hospital, London, UK
  4. 4Centre for Workplace Health, Northern General Hospital, Brearley Outpatient, Herries Road, Sheffield, UK
  1. Correspondence to Dr Paul Cullinan, Department of Occupational and Environmental Medicine, Imperial College (NHLI) and Royal Brompton Hospital, 1b Manresa Road, London SW3 6LR, UK; p.cullinan{at}

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


One of us was asked to consider a diagnosis of occupational asthma for a man who had worked for 20 years as a metal turner in a large, modern factory producing specialised machine parts. He described a 2 year history of severe breathlessness that improved when he was not at work. His spirometry was restrictive with a FEV1 of 1.35 L (40% predicted) and FVC of 1.8 L (45% predicted), a ratio of 75%. Other lung function measurements indicated gas trapping; his TLC was 5.01 L (79% predicted) and RV/TLC 170% predicted. A high resolution CT scan of his lungs revealed a widespread ‘mosaic’ pattern of attenuation indicative of small airflow obstruction. We made a diagnosis of occupational extrinsic allergic bronchioloalveolitis and recommended that he change his work. After 12 months working elsewhere in the same company, away from the machine shop, his dyspnoea was greatly improved but had not disappeared; his FVC had increased to 2.41 L, his FEV1 to 1.45 L and his TLC to 5.36 L.

Four months later we were referred a man who was also a metal turner in the same factory. For 2 years he had been a patient in a specialist interstitial lung disease clinic with a diagnosis of chronic hypersensitivity pneumonitis. A marked lymphocytosis in his bronchoalveolar lavage suggested ongoing exposure to an external cause. The nature of this had not been established although the positive findings of an autoimmune screen had led to conjecture of an ‘autoimmune’ aetiology, and of a high level of serum-specific IgG antibodies to Aspergillus species, that exposure to ‘mould at home or work’ might be relevant; an occupational history noted only that he worked for a machine parts manufacturer. While continuing to work …

View Full Text