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DISEASES OF THE URINARY ORGANS. 



USES OF THE URINARY ORGANS. 



The urinary organs constitute the main channel through which 

 are excreted the nitrogenous or albuminoid principles, whether de- 

 rived directly from the food or from the muscular and other nitro- 

 genized 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 nat- 

 ural 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 bacteria 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 poi- 

 sons quickly show their presence in resulting disorders of the skin 

 and connective tissue beneath it, of the nervous system, or other or- 

 gans. Nor is this influence one-sided. Scarcely an important organ 

 of the body can suffer derangement without entailing a correspond- 

 ing disorder of the urinary system. Nothing can be more striking 

 than the mutual balance maintained between the liquid secretions 

 of the skin and kidneys during hot and cold weather. In summer, 

 when so much liquid exhales through the skin as sweat, compara- 

 tively little urine is passed, whereas in winter, when the skin is in- 

 active, the urine is correspondingly 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, dis- 

 solved in the urine, serves to irritate the skin and produce trouble- 

 some 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), 

 favor the formation of stone, of taurocholic acid, and other bodies 

 that tend, when in excess, to destroy the blood globules and to cause 

 irritation of the kidneys by the resulting hemoglobin excreted in the 

 urine, and of glycogen too abundant to be burned up in the system, 

 which induces diabetes. Any disorder leading to impaired func- 

 tional activity of the lungs is causative of an excess of hippuric acid 

 and allied bodies, of oxalic acid, of sugar, etc., in the urine, which 

 irritate the kidneys even if they do not produce solid deposits in the 

 urinary passages. Diseases of the nervous system, and notably of the 

 base of the brain and of the spinal cord, induce various urinary dis- 

 orders, prominent among which is diabetes. In all extensive inflam- 

 mations and acute fevers the liquids of the urine are diminished, 

 while the solids (waste products), which should form the urinary 



