[Ultrastructure of the red pulp of the spleen in various anemias].

Eighteen tissue samples of human spleens obtained from patients suffering from hereditary sphaerocytosis, acquired haemolytic anaemia, hypersplenism, Banti's syndrome and extralienal neoplastic disease were subjected to electron microscopical examinations. Lesioned erythrocytes were removed with the aid of the macrophages of the red pulp and in cases of a high number of injured erythrocytes the cells lining the sinuses were also involved. The proliferation of collagen connective tissue was possibly also involved in injuring the blood cells. The spleens obtained from patients with neoplastic disease not affecting the spleen could not be regarded as normal.