The clinical examination of the urine in relation to disease / by C. Black.

  • Black, C.
Date:
1870
Catalogue details

Licence: Public Domain Mark

Credit: The clinical examination of the urine in relation to disease / by C. Black. Source: Wellcome Collection.

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    functional nature, as well as in other diseases in which these organs are wont to he greatly disturbed, as in gout and acute rheumatism, the specific gravity of the urine varies considerably. In dyspepsia the tendency of the affection is, to raise the specific gravity of the urine, because the food taken into the stomach cannot undergo that complete digestion which is necessary for the formation of healthy blood; and being, therefore, incapable of assimilation by the tissues of the body, it simply undergoes those transformations which direct its elimination by the kidneys, through which it passes more especially as the urates of the alkalies, and thus increases the specific gravity of the ui-ine. In that form, however, of dyspepsia which is distinguished by the epithet “ irritable,” the specific gravity of the urine is often suddenly diminished. When such is the case, it follows pain of the stomach consequent on the ingestion of food, the excitement of which, being apparently trans- mitted through the great sympathetic to the renal plexus of nerves, rouses the secretory action of the kidneys, and thus induces an increased secretion of urine, the specific gravity of which is conse- quently below the natural standard. In the early stage of organic disease of the stomach, as in scirrhus of that organ, the urine is generally either of the natural density or several degrees below it; but no sooner has the stage of ulceration arrived, than the specific gravity shows a tendency to increase. For this change an easy explanation is found in the fact, that the dis- integration which, at this stage, is advancing in the walls of the stomach, and the, probably, consequent absorption of morbid matter into the veins—the powerful impression which is, by the presence of cancerous elements in the blood, made upon the structures of the body in diminishing their vitality, and in thus favouring their dissolution—and the effect of a diminished supply of food and of the imperfect digestion and assimilation of the very small quantity which the stomach is, at this juncture, able to retain, determine an increased amount of solids to the kidneys, through which, in their transformations into urea, uric acid and its resultant salts with ammonia, potash, and soda, as also into purpurine, pass off by the urine with a necessary increase in the density of that secretion. Hence the daily observation of the specific gravity of the urine would, in such instances, become, to a certain extent, the measure of the progress of the disease. This fact, true with respect to disease of the stomach, is no less true of the morbid affections of the liver. In hypertrophy, in cirrhosis, in cancer, in tubercle, in