
Your kidneys are 2 bean-shaped organs that produce urine. They’re about the size of your fist and are in the back of your abdomen, near your spine. Kidneys balance your body’s water and mineral levels and filter waste out of your blood.
What is acute kidney failure?
An acute problem is one that has just started and probably won't last too long. So, acute kidney failure is when one or both of your kidneys suddenly stop working for a few days or weeks. If your kidneys stop working for a long time, you have chronic kidney disease Chronic Kidney Disease Your kidneys are 2 bean-shaped organs that produce urine. They're about the size of your fist and are in the back of your abdomen, near your spine. Kidneys balance your body’s water and mineral... read more .
Doctors now use the term "acute kidney injury" to refer to acute kidney failure. But kidney failure is still the term most people know.
Damage to one kidney doesn't cause major problems as long as your other kidney works—both of your kidneys need to stop working for you to have serious problems
You may have swelling of your feet, ankles, or face, feel sick and tired, itch all over your body, have difficulty breathing, or urinate (pee) less than usual
Acute kidney failure can lead to serious problems, such as heart failure Heart Failure Your heart pumps blood to carry oxygen and nutrients to the rest of your body. Heart failure is when your heart doesn’t pump blood as well as it should. It doesn’t mean your heart has stopped... read more
The Urinary Tract
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What causes acute kidney failure?
Acute kidney failure can be caused by:
Not enough blood getting to your kidneys
Something that blocks urine from draining out of your kidneys
Certain kidney diseases
Certain drugs or poisons
Your kidneys need a lot of blood. Your kidneys may not get enough blood if you have a lot of bleeding, have gotten very dehydrated, or your heart isn't pumping enough blood.
If a cancer or a kidney stone blocks the flow of urine, pressure builds up in the kidney. If the pressure stays high for a long time, your kidneys will be damaged.
Many drugs and other substances can damage your kidneys, for example:
Some antibiotics
Contrast agents used for certain x-rays
Contrast agents are liquids given by vein that make blood vessels and organs easier to see on x-rays.
Doctors often can’t find a cause for a person's acute kidney failure.
What are the symptoms of acute kidney failure?
Your symptoms depend on:
How badly your kidney is injured
What caused your acute kidney failure
How quickly your kidney problems are getting worse
First, you may have symptoms that include:
Weight gain
Swelling in your feet and ankles
Puffiness in your face and hands
Urinating less or not at all—most healthy adults urinate between 3 cups and 2 quarts of urine per day
Later symptoms:
Feeling sick to your stomach, tired, and less hungry
Trouble focusing
Itchiness or rashes
You also may have symptoms of the problem that caused your kidney failure.
How can doctors tell if I have acute kidney failure?
Your doctor will do:
Blood tests to measure whether waste products are building up in your blood
Urine tests
Imaging tests, such as ultrasound Ultrasonography Ultrasonography is a safe imaging test that uses sound waves to create a moving picture of the insides of your body. Ultrasonography doesn't use radiation (x-rays). Ultrasonography is also called... read more
or CT (computed tomography) scan Computed Tomography A CT scan uses a large machine shaped like a large donut to take x-rays from many angles. A computer then takes the x-rays and creates many detailed pictures of the inside of your body. Each... read more
How do doctors treat acute kidney failure?
Doctors treat the problem that is causing your acute kidney failure. Your doctor may also:
Put you on a special diet that limits how much fluid, salt, phosphorus, and potassium you take in
Have you weigh yourself each day to tell whether you're retaining fluid
Give you medicine to balance the potassium or phosphorus levels in your blood
Put you on dialysis Dialysis Dialysis is an artificial process for removing waste products and excess fluids from the body, a process that is needed when the kidneys are not functioning properly. There are a number of reasons... read more
to help remove waste and excess water from your blood
Some kidney injuries are severe and life-threatening, and need to be treated in a special care unit in the hospital. You may need surgery, for example, if your kidneys and urine flow are blocked.