Pathological Changes in Liver and Spleen in Nutritional Anemia in Rat

Abstract

Pure milk fed to young rats produces severe anemia which finally results in death in the majority of cases. In our studies of the pathological changes which take place during the course of nutritional anemia in the albino rat, the findings in the liver and spleen seem to have considerable value in the differential diagnosis of this type of anemia as contrasted with the infectious type caused by Bartonella muris. All our examined animals showed a severe degree of anemia with an erythrocyte count of less than 3 million per c.mm. and a Hb content of less than 4 gm. per 100 cc. Most of the animals died spontaneously, while 5 were killed during the course of the disease. The spontaneous death of the anemic animals was consistently preceded by a rapid loss of weight during the last days of life. The liver and spleen were weighed and fixed with the other organs in Zenker, alcohol and formalin. Slides for microscopic study were stained with hematoxylin-eosin, van Gieson, Mallory, Bielschovsky, Sudan III and Turnbull's Iron stain.

Changes in the Liver. Macroscopically, the changes were not marked. The size and weight were slightly decreased, the surface smooth and pale, the consistency soft. The cut surface showed a slight yellowish brown mottling and occasional small petechial hemorrhages.

The microscopic changes were most pronounced in those animals which died spontaneously from anemia. The central veins and the capillaries in the center of the lobule were greatly distended and filled with an edematous fluid. In the center of the liver lobule the cells were atrophied; those near the center were swollen and showed a marked vacuolization of the plasma. The majority of these vacuoles proved to be fat droplets when stained with Sudan III. They completely filled the cells surrounding the atrophic areas in the center of the lobule and were present even in livers in which atrophy of the central part of the lobules was just in the beginning stage. The periportal zones showed marked hypertrophy of the cells, with no fat, and an increase in the size of the cell and of the nucleus. Most of the cells contained 2 or more nuclei.