alveolitis

inflammation of an ALVEOLUS or alveoli. Chronic inflammation of the walls of the alveoli of the lungs is usually caused by inhaled organic dusts ( extrinsic allergic alveolitis; see BIRD-FANCIER LUNG , FARMER'S LUNG ) but may occur spontaneously (cryptogenic fibrosing alveolitis). The latter may be associated with connective tissue diseases, such as rheumatoid arthritis or systemic sclerosis. Both types of alveolitis may progress slowly to a state of fibrosis, and both types usually respond to corticosteroid and immunosuppressant therapy if the fibrosis is not severe