IDIOPATHIC PULMONARY CEROIDOSIS

An autopsy case of diffuse pulmonary ceroidosis was presented in a 55 year‐old man who had died suddenly. Autopsy, revealed noteworthy findings only in the lungs. Light microscopically, brown pigmented cells were proved to diffusely proliferate in the pulmonary tissue, particularly in the alveolar spaces. Histochemically, intracytoplasmic accumulation of ceroid‐like pigment was confirmed in the majority of the pigmented storage cells. Hemo‐siderin‐laden cells were less frequent or rare. Ultrastructurally, numerous osmiophilic inclusions delimited by a single membrane were present in the cytoplasm of the storage cells. No evidences of any basic disorders to induce such a pulmonary ceroidosis were detected at autopsy. From these findings, this case should be called "idiopathic pulmonary ceroidosis". In reviewing the literature, such a peculiar pulmonary disorder has never been recorded to date. Pathological distinction of this disorder from various pulmonary hemosideroses was discussed.