What is kidney failure?

Kidney failure occurs when your kidneys are not able to function properly. There are two types of kidney failure:

Acute kidney failure happens quickly over days or weeks and may occur due to dehydration, surgery, serious infections and certain drugs.
Chronic kidney failure, or chronic kidney disease (CKD), happens progressively over years. CKD is not reversible. It requires replacement of kidney function, with dialysis or transplantation, when the total kidney function is below 10-15%; this is often referred to as End Stage Renal Disease (ESRD).