Function of the Kidneys



The kidney system is often referred to as the filtering mechanism of the body. Right, and this is precisely what it manages to do. During its journey around the body, the blood constantly passes through this intricate network. An enormous amount of fluid is filtered off in the microscopic mechanism of the kidneys. Much of this is reabsorbed, and rejoins the blood as it courses around the system.

The blood contains large amounts of chemicals, foods, vitamins and nutrients that supply the cells with foods needed for normal wear and tear and repair. It also provides fuel and oxygen needed to produce energy. But as it yields these necessary items to the muscles and organs, in return it receives from them the unwanted by-products of the work they have been performing. These are called by-products of body metabolism. As the blood circulates, more and more are collected. They must be disposed of somewhere, and this is what the renal or kidney system is all about.



What happens when the unwanted material is screened out?

It is conveyed in the form of fluid, mostly water, from the internal part of the pelvis of the kidneys down a tube, one from each kidney, to the bladder. Here it accumulates until a suitable time occurs when it may be voided via another outlet tube called the urethra. This is called the act of micturition.

Doesn’t the kidney also have another function?

Yes. This is to maintain equilibrium of all the various other components of the blood system. It is sometimes referred to as homoeostasis. The body needs a delicate balance of a large variety of chemicals. The kidney manages to perform this in a wonderful way. It also manufactures hormones of its own, and these play a significant part in keeping the blood pressure normal. If too much is produced, it may lead to elevated readings, which may be serious. But in general, the two kidneys do a magnificent job in helping to keep the system normal throughout life.



Isn’t the kidney fairly susceptible to birth abnormalities?

Yes. The kidney and the heart are probably affected more commonly than most other internal organs. Sometimes swellings and cysts may form, or tubes may be partially or wholly blocked. Severe disorders (called hydronephrosis) may take place.

I might add that in the past few years with new sophisticated methods of checking babies before they are born, many of these can be detected prior to birth. In some cases, enterprising surgeons have actually operated on the baby before birth, rectified the abnormality, returned the baby to the womb, and waited for the birth to take place. Several successful attempts have been made. I am sure that in the future, more successes will also take place. It is an interesting and exciting new field.



Since it is in direct communication with the exterior, I suppose this system is also prone to infections, in the same way that the throat and lungs are at risk? Correct. Probably the most common problems are associated with recurring bacterial invasions of the bladder and kidney system.