22 DISEASES OF THE KIDNEY. 



become the practice of the better class of physicians to make careful 

 examination of the urine. Hospital patients do not generally apply 

 for aid until the dropsy has appeared. Exclusion of other causes of 

 dropsy will establish a strong presumption that we have a case of 

 Bright's disease to deal with. Examination of the urine places the 

 diagnosis beyond a doubt. In private practice, the observant and ex- 

 perienced practitioner will have recognized the disease before the 

 dropsy sets in. The history of the case is almost invariably as follows : 

 The patients have long remarked a failure of their strength, and a 

 pallor and anaemic aspect of their skin, and visible mucous membranes. 

 As all their functions are apparently normal, they are unable to ac- 

 count for this paleness and debility. The physician, after careful ex- 

 amination of all other organs, can find no appearance of disease to 

 which the loss of strength and impoverishment of the blood can be 

 ascribed. He examines the urine, and finds it to be loaded with albu- 

 men, and the symptoms are accounted for. No elaborate demonstra- 

 tion is required to show that, in addition to the other expenditures of 

 the blood, a daily loss from the blood of large quantities of albumen, 

 which may amount to from twelve to twenty grammes in the twenty- 

 four hours, cannot be made good by the daily supply of nourishment ; 

 or, in other words, a person subject to a daily drain from his blood of 

 from twelve to twenty grammes of albumen necessarily becomes pale, 

 bloodless, and enfeebled. As an examination of the urine reveals the 

 existence of the disease before the occurrence of the dropsy as well as 

 after it, it will be well to give a more detailed account of the charac- 

 teristics of the urine secreted in parenchymatous nephritis. It is gen- 

 erally of a pale-yellow color, and often exhibits a somewhat opalescent 

 reflection. As it is more viscid than common urine, on account of the 

 albumen which it contains, it is more easily made frothy than urine 

 free from albumen, and the froth lasts longer. When there is no in- 

 tercurrent febrile disease, its specific gravity is remarkably low, and 

 may sink to 1005. This is principally on account of a decrease in its 

 urea, and in a lesser degree owing to a diminution of the salts, especial- 

 ly the alkaline chlorides. The reduction in the amount of urea cannot 

 at first be ascribed to its retention in the blood. It would seem 

 rather that, just as in other hydrsemic conditions in which the urine is 

 abnormally light, the metamorphosis of material in the body is going 

 on more slowly than is natural, thus retarding the production of urea. 

 The explanation of Schmidt as to the decrease in the saline constitu- 

 ents of the urine, especially its alkaline chlorides, is less satisfactory, 

 namely, that the saline ingredients of the blood augment as its albu- 

 men diminishes, and vice versa. When the patients are already drop- 

 sical, the transfer of the chlorides into their dropsical effusion is a 



