What is Chronic Kidney Failure?

The kidneys are formed by a twin pair of bean-shaped, fist-sized organs. They are located in the middle of the back, just above the waist. They are vital for survival, but humans can live and follow a normal life with just one kidney. Their main functions are to filter waste products from the blood and maintain the balance between the body’s salt (electrolyte) and water levels. The kidneys are part of the urinary system along with the urethra, urinary bladder and ureters.

In function of their weight, the average adult has between 4 and 6 litres of blood circulating around their body. The renal arteries supply and circulate blood through the kidneys. Each kidney relies on over 1 million tiny filters (nephrons) to purify/filter approximately 1500 litres of blood per day. The substances filtered by the kidneys, along with water, are transformed into urine. Urine leaves the kidneys via some small tubes (ureters) and then accumulates in the bladder. If the kidneys do not eliminate the by-products they accumulate in the blood and have a negative impact on the body.

The kidneys also produce hormones: active vitamin D, required to absorb calcium from foods; and erythropoietin, which regulates blood pressure and stimulates red blood cell production.

Els ronyons també produeixen hormones: la vitamina D activa necessària per absorbir el calci dels aliments i l’eritropoetina, important per regular la tensió arterial i estimular la producció de glòbuls rojos.