700 WALTER J. HIGHMAN AND JEFFREY C. MICHAEL 



cannot be arbitrarily gauged. This subject merits extensive study, as it is 

 quite likely that a deeper insight into these conditions would be no less 

 valuable to alert internists than to dermatologists. 



Dermatoses Conceived to be Due to or Associated with 



Renal Disease 



\ 



This subject is too difficult to analyze in detail. The physiological 

 balance between perspiration and urine is such that one would expect 

 renal disturbances to involve the skin more frequently than apparently 

 occurs. The subtler phenomena of the excretion of substances soluble 

 in the urine, namely, the end products of metabolic waste, would appar- 

 ently be related to many dermatoses. Thus, in the various forms of 

 nephritis, one would fancy that the skin would exhibit numerous changes, 

 This is not the case, though, except in the presumptive instances to be 

 indicated below, in connection with disturbed nitrogen metabolism. 



One condition, nevertheless, which clinically simulates prurigo, and 

 which is associated with chronic nephritis, must be mentioned. It is not 

 known, however, whether this is fact or only surmise, or with what type 

 of nephritis it is prevailingly associated. TJremic patients often scratch 

 themselves, but whether they really have a pruritus, or whether the scratch- 

 ing is a manifestation of lowered mentality, cannot be stated. If there 

 is any connection between nephritis and cutaneous reactions, its expression 

 must be most exceptional, for in hundreds of cases of kidney disease of 

 this sort, one rarely finds a single instance of skin involvement. 



In other renal diseases, such as hydro- and pyonephrosis, pyelitis, 

 perinephric diseases, and the like, skin diseases have never been reported. 

 Renal tumors cause none, but in other conditions a certain relationship 

 appears to exist. Scarlatina scarcely is a fair example, for the nephritis 

 appears long after the acute cutaneous phase of the disease has subsided. 

 On the other hand, the more marked forms of arsphenamin and mercury 

 dermatitis are at times associated with nephritis, sometimes hemorrhagic, 

 and occasionally accompanied by uremia, while in bichlorid poisoning 

 there may be cutaneous phenomena, with the well-known renal reaction. 



Dermatoses Conceived to be Due to or Associated with 



Nervous Diseases 



The relationship between the central and peripheral nervous system 

 and cutaneous diseases is not definite, except in few instances, although 

 it is surmised in many diseases of the cord, such as syringomyelia, Mor- 

 van's disease and tabes which produce well-known trophic ulcers, includ- 





