May also be called: Renal Failure; Acute Renal Failure; Acute Kidney Failure; Acute Kidney Injury; Chronic Kidney Failure; Chronic Renal Failure; Chronic Kidney Disease

Kidney failure is a condition that happens when the kidneys lose their ability to filter waste products from the blood.

More to Know

Kidneys are bean-shaped organs located near the middle of the back, just below the ribs. They help to clean the blood by removing things like excess fluids, salts, and waste products from the blood. The waste products then leave the body as urine.

If the kidneys stop working correctly, harmful waste products and excess fluid build up. Blood pressure may also rise and the body might not make enough red blood cells. This is called kidney failure. If left untreated, it quickly can become life threatening.

Diabetes and high blood pressure are the most common causes of kidney failure in adults. It can also be due to genetic diseases, birth defects of the kidneys or urinary tract, and diseases that damage the glomeruli, which are the tiny filtering units in the kidneys. Kidney failure can happen suddenly (acute kidney failure) or over time (chronic kidney disease).

Treating the underlying condition that's causing the kidney failure can sometimes help heal the kidneys. But this isn't possible if someone has lost too much function in both kidneys. When this happens, doctors may recommend a kidney transplant or dialysis, a process that does the work of the kidneys by artificially cleaning the blood.

Keep in Mind

The damage to kidneys from acute kidney failure can sometimes be reversed, and people in good health may recover normal kidney function. If the kidneys do not recover, a kidney transplant may be needed. Transplants are becoming more and more successful because of advances in surgery and medications that help the body accept a transplanted kidney.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.