Abstract

A 66 year old man had inhaled cotton fibre for 50 years at his workplace. He did not have any respiratory symptoms. Chest CT scans revealed diffuse centrilobular and peribronchovascular interstitial thickening. Lung biopsy specimens confirmed the presence of string-like foreign bodies as well as granulomas and fibrosis in the peribronchial region. Infrared spectrophotometry confirmed that the foreign bodies were composed of natural cellulose. This is the first study to show directly by examination of biopsy samples that cotton fibre inhalation can cause diffuse lung disease. The clinical features of the disease were entirely different from those of byssinosis.