TNF-blockade has been increasingly used in the treatment of rheumatoid arthritis (RA). However, the safety is unclear and an increased risk of both tuberculosis and other infections has been identified. Recently severe fibrosing alveolitis has also been reported in RA-patients treated with TNF-blockade. We report a further six RA patients, who during treatment with infliximab or etanercept developed fulminant lung fibrosis with alveolitis. For four of the patients, the fibrosing alveolitis was fatal. All patients were RF positive and above 60 years and five had mild fibrosis associated with RA before TNF-blockade treatment. Duration of TNF-blockade treatment was for three patients only two months and for the other three, 20-51 months. Age above 60 years and previous lung fibrosis appear to be risk factors for developing fibrosing alveolitis in RA patients treated with TNF-blockade.