CYTOST IN MEDICINE 259 



presently, they may be caused by cytost also. For 

 an example we may consider nephritis, which may 

 be caused experimentally by various means. Various 

 metallic poisons, such as mercury and uranium, may 

 cause the onset of this condition. Likewise there is 

 considerable evidence that kidney damage may re- 

 sult from infections of one sort or another. In the case 

 of nephritis following burns, however, it is clear that 

 such factors are not the causative agent, and one is 

 forced to assign this role to cytost. One may reason 

 similarly concerning the other pathological conditions 

 enumerated above. 



In the case of arthritis deformans, this has been 

 recognized by Nathan (1917), for he states: 



"The principal gross and microscopical findings 

 in both acute and chronic joint disease, whether of 

 known or unknown origin, are fundamentally simply 

 phenomena of inflammatory reaction. 



"They are all of osseous origin. There are certain 

 peculiarities characteristic of so-called Arthritis De- 

 formans which are apparently very difficult to bring 

 into correlation with an infectious origin. Indeed the 

 peculiar deformities of hands and fingers, the acro- 

 paresthesia and premonitory weakness and spasm, 

 cannot be ascribed to an infectious focus within the 

 joint at all. It may show involvement of cord and 

 spinal roots, definite signs of peripheral nerve ab- 

 normalities, — at most Perineuritis, Ulnar neuritis, 

 etc. 



"It must be assumed that all polyarthritis (neu- 

 ritis) , is due to infections, or, that all deleterious sub- 

 stances cause fundamentally the same general changes 

 in articular structures. It cannot be denied that there 



