CHAPTER XVII 



EFFECTS ON THE SPLEEN 



The spleen, like the lymphatic system in general, usually undergoes atrophy 

 during conditions of inanition and malnutrition. The splenic enlargement 

 sometimes found is in most cases to be ascribed to complications, such as 

 tuberculosis, syphilis or other infections. After a brief summary, the effects of 

 inanition upon the spleen will be considered in detail under (A) effects of total 

 inanition and (B) effects of partial inanition. 



Summary or Effects on the Spleen 



As to the changes in the weight of the spleen during inanition, the great 

 normal variability makes it often difficult to reach conclusions. In general, 

 however, it is clear that during total inanition (likewise on water only) in human 

 and animal adults the spleen shares in the marked atrophy of the lymphoid 

 organs. The relative loss in the spleen weight is usually greater than the loss 

 in body weight, often twice as great; but the spleen loss may be slight in the 

 early stages of inanition (guinea pig) . In emaciated human adults, the spleen is 

 sometimes enlarged on account of complicating infections, such as tuberculosis 

 or syphilis. 



In the young, the results are more variable. In some cases there is a definite 

 decrease in the weight of the spleen, in others the inherent growth impulse may 

 overcome the tendency to atrophy during inanition. In atrophic human in- 

 fants, syphilis or other infections also may produce marked splenic enlargements. 



During hibernation and subsequent inanition, the changes in the weight of 

 the spleen appear very irregular. 



Upon ample refeeding after inanition, the normal weight of the spleen is 

 promptly restored, sometimes apparently with a transient over-compensatory 

 regeneration. 



During the various forms of partial inanition, the changes in the weight of 

 the spleen are variable. In human pellagra and famine edema, the spleen usu- 

 ally appears atrophic, but sometimes hypertrophied. In human rickets the 

 spleen usually presents an enlargement of doubtful significance (often due to 

 complications) . In experimental rickets of rats, the spleen is irregular in weight. 

 In human beriberi, the spleen is usually enlarged; whereas in animals on diets 

 deficient in vitamin B there is a very marked and constant splenic atrophy. In 

 human and animal scurvy, the spleen is variable in weight ; usually enlarged, but 

 often within normal range, or even subnormal in the early stages. During 

 thirst, there is a very marked loss in the weight of the spleen, comparable to that 

 during total inanition. 



During inanition in general, the structural changes of the spleen, though 

 varied in degree and character, usually present certain characteristic features. 



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