Fatal anhydrous ammonia inhalation

The morphologic and morphometric pulmonary alterations in a patient with anhydrous ammonia inhalation dying two months after exposure are described. Major pathologic findings included cylindrical bronchiectasis of the lower lobes, fibrous obliteration of small airways, and terminal nocardial pneumonia. Normal density of small airways was found, but the average diameter (0.50 mm.) was significantly less than that of controls (0.66 +/- 0.02). Fibrous obliteration of small airways may be characteristic of a late stage of bronchiolitis obliterans and is probably responsible for the chronic obstructive lung disease in the survivors of an episode of ammonia inhalation.