EFFECTS ON THE SPLEEN 283 



excluded. These changes may affect the hemopoietic function of the spleen 

 and be related to the anemia occurring in rickets, as was also emphasized by 

 Saricinelli ('03). He found at first a hyperplasia of the splenic pulp followed 

 by a progressive proliferation of the connective tissue stroma, which gradually 

 replaces the parenchyma. Pfaundler ('22) holds that during rickets there is a 

 marked swelling of the lymphoid organs throughout the body. The spleen 

 is often enlarged, due to hyperplasia of pulp and follicles. 



Vitamin Deficiency.- — In some cases previously cited, such as infantile 

 atrophy, the effects are probably due in part to vitamin deficiencies. We may 

 consider these under the three well known vitamins — A, B and C. 



Deficiency of vitamin A alone has apparently no marked effect upon the 

 spleen, according to experiments on rats by Emmett and Allen ('20) and Cramer, 

 Drew and Mottram ('21a). Davis and Outhouse ('21) noted frequent conges- 

 tion of the splenic sinuses, but no degenerative changes. Meyerstein ('22) 

 made a few observations on the spleen in young white rats on diets deficient in 

 vitamins A and B. 



Vitamin B. — In 125 cases of human beriberi, Ellis ('98) found the average 

 weight of the spleen 9.27 ounces, in comparison with 6.28 ounces in 204 dying 

 from other causes, thus indicating a hypertrophy of the spleen in beriberi. 

 Strong and Crowell ('12) noted some congestion of the spleen, with relatively 

 small follicles. Andrews ('12), in 18 necropsies of infantile beriberi, likewise 

 found the spleen very hyperemic, and even hemorrhagic; but with no increase 

 of splenic tissue. Nagayo ('23) claimed that splenic passive congestion dis- 

 tinguishes human beriberi from experimental polyneuritis. 



In experimental beriberi (or polyneuritis) produced in pigeons by polished 

 rice diet (deficient in vitamin B), Funk and Douglas ('14) mentioned atrophy 

 and degenerative changes in the spleen, among other organs. . Tasawa ('15) 

 studied the effects in about 150 pigeons and 200 fowls, finding the body emaci- 

 ated and the spleen always atrophic; capsule wrinkled and thickened, and 

 trabecular conspicuous; the pulp atrophic and the follicles scarcely visible. 

 "Ein Bild wie die gewohnliche Stauungsmilz ist iiberhaupt nicht zu sehen." 

 Emaciation of the body and atrophy of the spleen were likewise noted by Mack- 

 enzie (' 1 5) in pigeons and by Drummond (' 1 6) in young chickens. 



Voegtlin and Lake ('19), in cats, dogs and rats with polyneuritis produced by 

 deficient diets, noted in the spleen degenerative changes similar to those (above 

 mentioned) found by Sundwall ('17), but less extensive. 



As previously mentioned, McCarrison ('19, '19a, '21) found that a diet of 

 milled and autoclaved rice gives rise to an atrophic degeneration of the spleen 

 and other organs in pigeons and monkeys. Atrophy of the lymphoid tissues 

 in general was observed. Brucco ('20) noted evidences of regenerative activity 

 in the spleen and bone marrow of dogs on a polished rice diet. Findlay ('21) 

 found a loss of 65-67 per cent in the spleen of fowls and pigeons with beriberi 

 (Table 13). Lopez-Lomba ('23) noted a brief increase preceding the marked 

 decrease in the weight of the spleen in adult pigeons on vitamin-free diet. 



Cramer, Drew and Mottram ('21) found in mice and rats that the spleen, 

 like the lymphoid tissue in general, undergoes a specific and profound atrophy 



