What is acute kidney injury?

Acute kidney injury (which used to be called acute renal failure) means that your kidneys have suddenly stopped working normally. Your kidneys remove waste products and help balance water and salt and other minerals (electrolytes) in your blood. When your kidneys stop working, waste products, fluids, and electrolytes build up in your body. This can cause problems that can be deadly.

Symptoms of acute kidney injury may include:

• Little or no urine when you try to urinate.
• Swelling, especially in your legs and feet.
• Not feeling like eating.
• Nausea and vomiting.
• Feeling confused, anxious and restless, or sleepy.
• Pain in the back just below the rib cage. This is called flank pain.

Some people may not have any symptoms. And for people who are already quite ill, the problem that's causing the kidney injury may be causing other symptoms.

Acute kidney injury is most often diagnosed during a hospital stay for another cause. If you are already in the hospital, tests done for other problems may find your kidney problem.

If you're not in the hospital but have symptoms of kidney injury, your doctor will ask about your symptoms, what medicines you take, and what tests you have had. Your symptoms can help point to the cause of your kidney problem.

Blood and urine tests can check how well your kidneys are working. A chemistry screen can show if you have normal levels of sodium (salt), potassium, and calcium. You may also have an ultrasound. This imaging test lets your doctor see a picture of your kidneys.

Your doctor or a kidney specialist (nephrologist) will try to treat the problem that is causing your kidney injury. Treatment can vary widely, depending on the cause. For example, your doctor may need to restore blood flow to the kidneys, stop any medicines that may be causing the problem, or remove or bypass a blockage in the urinary tract.

At the same time, the doctor will try to:

• Stop wastes from building up in your body. You may have dialysis. This treatment does the work of your kidneys until they recover. It will help you feel better.
• Prevent other problems. You may take antibiotics to prevent or treat infections. You also may take other medicines to get rid of extra fluid and keep your body's minerals in balance.

You can help yourself heal by taking your medicines as your doctor tells you to. You also may need to follow a special diet to keep your kidneys from working too hard. You may need to limit sodium, potassium, and phosphorus. A dietitian can help you plan meals.

• Talk to your doctor about how much fluid your child should drink.
• Be sure your child eats a healthy diet. Talk to your doctor or a dietitian about what type of diet may be best for your child. Your child may need to limit sodium, potassium, and phosphorus.
• If your child needs dialysis, follow the instructions and schedule for dialysis that your doctor gives you.
• Be safe with medicines. Read and follow all instructions on the label. Review all of your child's medicines with your doctor. Do not give your child any medicines, including nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin), unless your doctor says it is safe to do so.
• Make sure that anyone who treats your child for any health problem knows that your child has a history of acute kidney injury.