METABOLISM IN NEPHRITIS 399 



This differentiation from the clinical point of view depends largely upon 

 the fact that in nephrosis blood pressure is not raised above the normal 

 level while in acute diifuse nephritis it is. In most instances this is cor- 

 rect. When there is an acute toxic lesion in the renal epithelium as 

 occurs with arsenic, bichlorid of mercury or phosphorous poisoning, or 

 with some of the acute infections as diphtheria,- sepsis or typhoid fever, 

 no hypertension develops (Krehl(c) (e)). 



On the other hand, in some cases of bichlorid of mercury poisoning 

 when anuria develops, the blood pressure may rise. (Janeway, Volhard). 

 This may be explained on the basis that extreme renal insufficiency will 

 raise the arterial pressure irrespective of the type of kidney lesion. The 

 kidney affections characteristic of pregnancy are of the nephrosis type. 

 In this condition a marked rise of blood pressure, which evidently precedes 

 the development of albuminuria, is usually found. It seems probable that 

 this is an instance in which the hypertension and the renal disease depend 

 upon the same cause and that the rise in blood pressure is not brought about 

 by the kidney lesions. Some of the experimental animal nephroses have 

 been accompanied by a slight increase in arterial pressure; this has been 

 found in uranium, mercury, chromate and cantharidin poisoning (Zon- 

 dek(a), Mayet, Mosenthal(a)). 



Chronic Diffuse (Parenchymatous) Nephritis. Hypertension is absent 

 in many cases of chronic diffuse nephritis. This is the finding of Butter- 

 man to which the author agrees. In this type of nephritis, there is marked 

 albuminuria and no renal insufficiency except the retention of water and 

 salt at times, Volhard, in contradistinction to what has just been stated, 

 believes that increased blood pressure is a necessary accompaniment of 

 this form of kidney disease. Even he admits that the blood pressure usu- 

 ally drops to normal during rest in bed; until the arterial tension rises, 

 when the upright position is resumed, these cases are not to be differenti- 

 ated from "those partially healed instances of chronic diffuse nephritis 

 that exhibit a 'Restalbuminurie' and the chronic glomerulonephritis of 

 the focal infectious type." Here, as in acute nephritis, it may be said that 

 if we regard an augmented blood pressure as a pathognomonic sign of 

 chronic diffuse nephritis the truth of Volhard's conceptions is self-evident, 

 otherwise we are privileged to believe that the blood pressure may continue 

 at a normal level during the course of this malady. 



It is well established that the height of the blood pressure usually does 

 not rise above 180 mm. of mercury, and very rarely above 200 (Volhard 

 and Fahr). 



Secondary Contracted Kidney. Clinically and anatomically, it is 

 at times extremely difficult to differentiate the sclerotic, contracted kidney 

 which is the end result of acute and chronic diffuse nephritis (secondary 

 contracted kidney) from that following arteriosclerosis (primary con- 

 tracted kidney). Under the circumstances it is not to be wondered at that 



