DISEASES OF THE URINARY ORGANS. 



By James Law, F. R. C. V. S., 

 Formerly Professor of Veterinary Science, etc., in Cornell University. 



USES OF THE URINARY ORGANS. 



The urinary organs constitute the main channel through which are 

 excreted the nitrogenous or albuminoid principles, whether derived 

 directly from the feed or from the muscular and other nitrogenized 

 tissues of the body. They constitute, besides, the channel through 

 which are thrown out most of the poisons, whether taken _^in by the 

 mouth or skin or developed in connection with faulty or natural 

 digestion, blood-forming, nutrition, or tissue destruction ; or, finally, 

 poisons that are developed within the body, as the result of normal 

 cell life or of the life of bacterial or other germs that have entered the 

 body from without. Bacteria themselves largely escape from the 

 body through the kidneys. To a large extent, therefore, these organs 

 are the sanitary scavengers and purifiers of the system, and when 

 their functions are impaired or arrested the retained poisons quickly 

 show their presence in resulting disorders of the skin and connective 

 tissue beneath it, of the nervous system, or other organs. Nor is this 

 influence one-sided. Scarcely an important organ of the body can 

 suffer derangement without entailing a corresponding disorder of the 

 urinary system. Nothing can be more striking than the mutual bal- 

 ance maintained between the liquid secretions of the skin and kidneys 

 during hot and cold weather. In summer, when so much liquid ex- 

 hales through the skin as sweat, comparatively little urine is passed, 

 whereas in winter, when the skin is inactive, the urine is correspond- 

 ingly increased. This vicarious action of skin and kidneys is usually 

 kept within the limits of health, but at times the draining off of the 

 water by the skin leaves too little to keep the solids of the urine safely 

 in solution, and these are liable to crystallize out and form stone and 

 gravel. Similarly the passage, in the sweat, of some of the solids 

 that normally leave the body, dissolved in the urine, serves to irritate 

 the skin and produce troublesome eruptions. 



PROMINENT CAUSES OF URINARY DISORDERS. 



A disordered liver contributes to the production under different 



circumstances of an excess of biliary coloring matter which stains 



the urine; of an excess of hippuric acid and allied products which, 



being less soluble than urea (the normal product of tissue change) , 



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