388 HERMAN O. MOSENTHAL 



The diagnosis of this condition is not difficult. If the symptoms of 

 irritation or depression of the central nervous system are present, a dis- 

 tinctly elevated blood pressure exists, and the tests for renal function 

 indicate little or no curtailment of kidney efficiency, then it is justifiable 

 to assume that a cerebral arteriosclerosis is responsible for the symptoms. 

 The inability of clinicians to carry out tests for renal function in the past 

 few years has led to the inclusion of many of these cases among those re- 

 ported, described and discussed as uremia. For instance, Ascolis' famous 

 book on uremia evidently has many such instances in it. 



One of the very interesting and important aspects of this later ex- 

 planation of uremia is whether all the bizarre palsies of a fleeting or perma- 

 nent character that may affect many muscles, or only one limb or even a 

 single muscle, are not due to cerebral arteriosclerosis, and whether it is 

 necessary to invoke the aid of toxins of any sort to explain them. It is 

 unnecessary to add any further evidence to that already furnished by 

 Cohnheim (see preceding section) to deny that cerebral edema can have 

 any bearing. The whole matter can be cleared up only by careful clinical 

 observation followed by thorough and painstaking anatomical studies. 

 Such authorities as Krehl and Munk admit that grievous errors have been 

 made in confusing cerebral arteriosclerosis and uremia. The author is 

 of the opinion that, as time passes by, the focal lesions of the central nerv- 

 ous system attributed to "uremic poisoning" will in large part be traced 

 back to pathological changes in the cerebral arteries, occurring as an af- 

 fection entirely independent of Bright's disease. 



Renal Insufficiency. The poisoning characteristic of renal insufficien- 

 cy has been elucidated in several particulars during the past few years. 

 Intensive studies in blood chemistry by innumerable workers in many 

 institutions have made some of these conclusions possible. In the first 

 place, it is necessary to have the symptoms produced by marked renal in- 

 sufficiency clearly in mind. 



Foster(c)(1921) describes this condition very well: "I studied with 

 the greatest care from day to day, three patients who had been deprived 

 of the only functioning kidney by emergency operations. In none of 

 these was there the slightest evidence of irritability of the motor nervous 

 system, or impairment of the psychic functions until the last days of life. 

 None had amaurosis, muscle spasms, paralysis or convulsions. All alike 

 experienced first, weakness, slight vertigo and mental dullness; then a 

 tendency to sleep which lapsed into coma, with death on the ninth to 

 eleventh day after the operation." The author agrees with these findings 

 except in one particular: when the kidney becomes absolutely insufficient, 

 or nearly so, and the waste products accumulate within the body, an almost 

 constant symptom is rather fine muscular twitehings, noted in any of the 

 voluntary muscles and especially the forearms, hands and fingers ; this mus- 

 cular twitching will frequently precede the onset of coma for several days 



