Learn how and why kidney failure can happen, and why kidney failure hurts your body. Find out the symptoms of kidney failure, like retention of fluids, less urine, and confusion.

What is kidney failure?

The kidneys are two bean-shaped organs that lie on the left and right side of your spine, below your ribs and behind your belly. Each kidney is about the size of a fist: 4 or 5 inches long.

The kidneys' job is to filter your blood. They remove waste from the body, control your fluid balance, and maintain the correct levels of electrolytes. Each kidney has around a million tiny filters called nephrons to help with this. Even if 90% of your kidneys aren’t doing their job correctly, you might not notice any symptoms or problems.

However, if blood stops flowing into a kidney, part or all of it could die. That can lead to kidney failure.

When your kidneys lose the ability to effectively filter waste from your blood, kidney failure will occur. Some factors that can interfere with the health and function of your kidney include:

  • Exposure to toxins like environmental pollutants or certain medications
  • Trauma to your kidney
  • Certain acute and chronic diseases
  • Severe dehydration

What are the symptoms of kidney failure?

Kidney failure can give a person a wide range of symptoms. Normally, someone with kidney failure will have a few symptoms of the disease, but it’s also possible that a patient will not have any of the following symptoms. Possible symptoms include:

  • Reduced urine production
  • Retention of fluids because your kidney can’t eliminate water waste, which causes swelling in the legs, ankles, and feet
  • Shortness of breath
  • Seizures
  • More drowsiness or fatigue than usual
  • Constant and persistent nausea
  • Confusion
  • Chest pain or pressure
  • Coma

What are the causes of kidney failure?

Kidney failure can occur due to a variety of reasons. Some of the most common include:

  • Loss of blood flow to the kidneys, oftentimes due to a heart attack, liver failure, or dehydration
  • Urine elimination problems through obstructing tumors or through conditions such as kidney stones or a blood clot

How do doctors diagnose kidney failure?

There are several tests your doctor can use to diagnose kidney failure. These include:

  • Urinalysis, which uses a urine sample to test for kidney abnormalities
  • Urine volume measurements, during which your doctor measures your urine output to see if there’s blockage
  • Blood samples, which are used to measure substances normally filtered by your kidneys
  • Imaging tests such as ultrasounds, MRIs, and CT scans are used to provide your doctor with a clear picture of the kidneys urinary tract, which can show any blockages or abnormalities in the area
  • Kidney tissue sample, which is taken during a surgical procedure by your doctor to look for abnormal deposits, scarring, or infectious organisms

How do doctors treat kidney failure?

There are several treatments for kidney failure. Your doctor will determine the best treatment option for you, which may include:

  • Dialysis, which filters and purifies your blood using a machine in place of your kidneys. Dialysis cannot cure kidney failure, but it can keep your body stable if you go to regularly scheduled treatments as you await a transplant.
  • A kidney transplant, which replaces your unhealthy kidney with a healthy one. There’s usually a long wait to receive a donor that’s compatible with your body, but if you have a friend or family member who is willing to be a living donor, the process may go more quickly.