This section is from the book "The Human Body: An Elementary Text-Book Of Anatomy, Physiology, And Hygiene", by H. Newell Martin. Also available from Amazon: The Human Body.
The Kidneys, being the chief organs for the excretion of nitrogen waste, are among the most important organs of the body. Any defect in their healthy activity leads to serious interference with the working of many organs, due to the accumulation in the body of nitrogenous waste products.*
If both kidneys be cut out of an animal, it dies in a few hours from blood-poisoning, due to accumulation of waste poisonous substances which the kidneys should have got rid of. Serious kidney-disease amounts to pretty much the same thing as cutting out the organs, since they are of little use if not healthy. It is always fatal if not checked, and often kills in a short time. The things which most frequently cause kidney-disease are undue exposure to cold, and indulgence in alcoholic drinks.
Where does the ureter convey it?
Is the bulk of the renal secretion greater in summer or in winter ? Why? What is its average daily amount? How much urea does it contain ? How much nitrogen is contained in this quantity of urea?
Why are the kidneys important organs ? What follows when their physiological work is defective ?
* Bright's Disease, one of the commonest and most dangerous of maladies, consists essentially in an alteration of the kidney structure, in consequence of which these organs cease to eliminate urea from the blood, and drain off pure albumen from it instead. The three most common causes of Bright's disease are (1) an acute illness, as scarlet fever, of which it is a frequent result, (2) sud den exposure to cold when warm (this often drives blood in excessive amount from the skin to internal organs and leads to kidney disease); and (3) the habitual drinking of alcoholic liquids.
Cold Causes Kidney Disease partly by driving blood from the surface and congesting the kidneys, partly by throwing too much work on them. When the skin does not get rid of its proper share of the waste matters of the body, it is the kidneys which have to make up the deficiency.
Nearly all the infectious diseases which are accompanied by a rash on the skin, as measles and scarlet fever, also affect the kidneys. During these diseases the kidneys are more or less inflamed, and in the early stages of recovery they are still weak and easily injured. Under these circumstances, exposure to cold is very apt to cause incurable kidney-disease.
 
Continue to: