Kidney function

Kidney function is critical to health and survival.

The kidneys excrete waste products and chemicals (including drugs), regulate body fluid, maintain acid-base balance and control blood electrolyte levels. They achieve this by closely regulating the volume and composition of urine. In addition the kidneys have several endocrine functions - they activate vitamin D (needed for calcium balance), facilitate red cell formation (through the secretion of erythropoietin) and regulate blood pressure (through the production of renin).

To function the kidneys need adequate renal blood flow and oxygenation. The parenchyma or 'substance' of the kidneys must be healthy, rather than damaged or inflamed by disease processes. Finally, the kidneys must be able to drain urine freely through a functioning urinary tract.