Copyright © 2004, Elsevier Science (USA) All rights reserved.

The kidney is of paramount importance in the maintenance of homeostasis. Despite its relatively small mass, the kidney processes enormous amounts of solute and water daily and finely regulates the excretion of most substances to match their rates of ingestion and production by metabolism.

Data compiled for the 2002 Annual Report of U.S. Renal Data System ( show that in 2000 (the latest year for which complete data were available) more than 96,000 people in the United States developed end-stage renal disease (ESRD), a condition in which the patient has little or no kidney function and would die without hemodialysis or a kidney transplant. In that same year, more than 275,000 patients received hemodialysis and more than 103,000 were sustained by a successful renal transplant. Treatment of ESRD in 2000 cost more than $12.3 billion in Medicare and even more in private, charitable, and other public health care funds! The increasing prevalence and incidence of ESRD are especially disappointing in view of the fact that diabetes mellitus (especially type 2 diabetes) and hypertension accounted for, respectively, ~44% and ~25% of the cases. Early treatment in both types of cases would greatly reduce the enormous human and monetary costs of ESRD. Furthermore, ESRD represents only the tip of the iceberg among chronic and acute renal diseases. Many nonfatal conditions such as urinary incontinence and other disorders of urination severely compromise the quality of life for millions.

One usually thinks of the kidney in terms of its role in ridding the body of metabolic by-products, and this function is certainly important. When the operation of the kidneys is compromised to a sufficient extent, numerous metabolites such as urea, creatinine, uric acid, sulfate, and phosphate begin to accumulate in the body fluids. The accumulation of these and other substances in blood leads to the syndrome called uremia, which signals the progression of renal failure. The kidneys are also a primary component of the body's defense against toxins and other foreign substances in the environment. The kidney excretes many of these substances and their metabolites, whether they are taken into the body directly or produced by the metabolism of other substances.

Despite the importance of the excretion of metabolic waste products and potential toxins, the threat to life in renal failure typically comes not from the accumulation of metabolic wastes or environmental toxins, but from the loss of the body's ability to balance the daily intake of salts and water by an appropriate rate of excretion. In the patient with renal failure, a frequent presenting symptom is the edema that results from the resulting retention of salt and water. The expansion of the blood plasma volume increases the workload of the heart and eventually leads to heart failure and pulmonary edema. These events are often complicated by acidosis and hyperkalemia (a high blood K+ concentration), which result from the inability of the kidneys to excrete acids and potassium at the proper rates.

To understand the progression of these disorders and their management, it is necessary to understand the normal functions of the kidney and the location and mechanisms that underlie those functions. But even more important is an understanding of how these processes are regulated by a variety of hormonal, neural, and local control mechanisms to respond appropriately to various factors that tend to disturb homeostasis.

Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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