Pulmonary interstitial fibrosis associated with alveolar proteinosis.

Abstract

Alveolar proteinosis is characterised by the presence of an amorphous lipoproteinaceous material that fills the alveolar space and stains positively by the periodic acid Schiff. (PAS) method.' Alveolar walls are usually normal or only slightly thickened by cellular infiltrate, and interstitial fibrosis is unusual. We report a patient in whom severe interstitial fibrosis occurred early in the course of the dis- ease and led to a delay in correct diagnosis and to inappropriate treatment with corticosteroids.