Definition Diseases Symptoms Tests Treatment Sources

What are they?
The urinary system cleanses the blood and rids the body of excess water and waste in the form of urine. The urinary tract consists of two kidneys, two ureters (one from each kidney), tubes that drain urine from the kidneys into the bladder (a storage sac), and the urethra (the tube that transports the urine out of the body). Muscles help control the release of urine from the bladder.

The kidneys, a pair of bean-shaped organs, are located at the bottom of the ribcage in the right and left sides of the back. Although the body is equipped with two kidneys, you can function with one reasonably healthy kidney if the other is damaged or removed. The kidneys receive blood from the aorta, filter it, and send it back to the heart with the right balance of chemicals and fluid for use throughout the body. The urine created by the kidneys is moved out of the body via the urinary tract.

The kidneys control the quantity and quality of fluids within the body. They also produce hormones and vitamins that direct cell activities in many organs; the hormone renin, for example, helps control blood pressure. When the kidneys are not working properly, waste products and fluid can build up to dangerous levels, creating a life-threatening situation. Among the important substances the kidneys help to control are sodium, potassium, chloride, bicarbonate HCO3- (measured indirectly as CO2), pH, calcium, phosphate, and magnesium.

On This Site

Tests: albumin, calcium, creatinine, estimated GFR, creatinine clearance, electrolytes, erythropoietin, microalbumin, parathyroid hormone, phosphate, potassium, prealbumin, renin, urinalysis, urine culture, vitamin D
Conditions: Diabetes, Autoimmune disorders, Lupus, Acidosis and Alkalosis, Proteinuria
In the News: Earlier Kidney Screening Recommended, Cystatin C: a kidney test that predicts cardiovascular problems and death in the elderly

Elsewhere On The Web

American Association of Kidney Patients
American Foundation for Urologic Disease
American Kidney Fund: Important Facts about Kidney Disease
National Institute of Diabetes & Digestive & Kidney Diseases: National Kidney Disease Education Program
National Kidney Foundation: About Kidney Disease
National Kidney Foundation Information Center
National Kidney and Urologic Disease Information Clearinghouse, National Institutes of Health
The Life Options Rehabilitation Program
Kidney School
Home Dialysis Central
Information on diabetic kidney disease:
National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health
National Kidney Foundation
Information on high blood pressure and kidney disease:
National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health
American Kidney Fund