Review of cryptogenic fibrosing alveolitis, including current treatment guidelines
- aSir William Leech Centre for Lung Research, Freeman Hospital, Newcastle Upon Tyne NE7 7DN, UK, bSunderland Royal Hospital, Sunderland, UK
- Dr Bourke
- Received 13 July 1999
- Accepted 20 January 2000
- cryptogenic fibrosing alveolitis
- idiopathic pulmonary fibrosis
- desquamative interstitial pneumonia
- usual interstitial pneumonia
Cryptogenic fibrosing alveolitis (CFA), known as idiopathic pulmonary fibrosis in the USA, is characterised by inflammation and fibrosis of the alveoli and interstitium of the lungs, favouring the subpleural and basal regions. By definition the diagnosis demands that all known causes of pulmonary fibrosis have been excluded. It is now clear that the CFA population is comprised of a heterogeneous group, with varying clinical, radiological and histological features, which in turn may be used to predict response to treatment and prognosis. The British Thoracic Society has recently produced guidelines on the investigation and management of diffuse parenchymal lung disease, including CFA.1
Epidemiology
Epidemiological data on CFA is limited. A population based registry of patients with interstitial lung disease was established in Bernalillo County, New Mexico, between 1 October 1988 and 30 September 1990.2 The incidence of idiopathic pulmonary fibrosis (excluding undefined pulmonary fibrosis) for men and women was 10.7 and 7.4/100 000/year respectively, and increased dramatically with age, reaching 102/100 000/year in men ≥75 years. Overall prevalence was 16.7/100 000 (reaching 28/100 000 including undefined pulmonary fibrosis); in contrast the prevalence in the UK has been estimated at 6/100 000.3 Population differences and more strict diagnostic criteria in the UK study may explain the difference.
The British Thoracic Society conducted a prospective observational study involving 588 newly diagnosed cases of CFA between 1 December 1990 and 31 November 1992. The mean age at presentation was 67.4 years, with a male:female ratio of 1.7:1.4 An earlier retrospective analysis of 220 cases in a tertiary centre UK study reported a 2:1 male preponderance, with an earlier mean age of onset of symptoms of 55 years (perhaps reflecting referral bias), and median survival of 40 months and 77.5 months for men and women respectively.5 Overall mean survival in the British Thoracic Society study was …
