Acute kidney injury is a sudden worsening of kidney function. The kidneys are organs that have several jobs. They filter the blood to remove waste products and extra fluid. They also maintain a healthy balance of minerals and hormones in the body, which helps control blood pressure and keep bones strong. With this condition, the kidneys do not do their jobs as well as they should.

This type of kidney injury develops within a few hours or days. Some children recover fully. Others may develop long-term problems.

What are the causes?

This condition may be caused by:

  • A sudden drop in blood or oxygen flow to the kidneys.

  • A direct injury to the kidneys.

  • A blockage in the urinary tract.

These causes can result from:

  • Medicines, including some antibiotics or chemotherapy drugs.

  • Contrast dye used in imaging tests.

  • Overuse of pain medicines called nonsteroidal anti-inflammatory drugs (NSAIDs).

  • Surgery.

  • Severe dehydration.

  • A bloodstream infection (sepsis).

  • Organ failure, including heart or liver failure.

  • Kidney disease.

What increases the risk?

This condition is more likely to develop in children who:

  • Had some surgeries, such as heart surgery or stem cell transplant.

  • Had certain conditions at birth, such as low blood oxygen levels or low birth weight.

  • Were born to a mother who took certain antibiotics or NSAIDs while pregnant.

  • Have had certain medical conditions, such as:

    • Certain forms of cancer, including acute lymphocytic leukemia and B-cell lymphoma.

    • Low blood platelets (thrombocytopenia).

    • Infection in the bloodstream.

  • Were treated with certain medicines, including some antibiotics, chemotherapy, or acetaminophen.

  • Are dehydrated.

What are the signs or symptoms?

Symptoms of this condition depend on the cause and may not be obvious until the condition becomes severe. They may seem unrelated to the kidneys. Symptoms may include:

  • Tiredness (lethargy) or difficulty staying awake.

  • Nausea and vomiting.

  • Swelling in the legs, ankles or feet, or around the eyes.

  • Problems with urination, such as producing little or no urine.

  • Pain in the abdomen, or pain along the side of the stomach (flank).

  • Muscle twitches and cramps, especially in the legs.

  • Confusion or trouble concentrating.

  • Loss of appetite.

  • Fever.

How is this diagnosed?

This condition is diagnosed based on your child’s symptoms, medical history, and a physical exam.

Other tests may be done, such as:

  • Blood tests.

  • Urine tests.

  • Imaging tests.

  • Removing a sample of tissue from the kidneys to be checked under a microscope (kidney biopsy).

How is this treated?

Treatment for this condition depends on the cause and how severe the condition is. Treatment may include:

  • Fluids if your child is dehydrated. They will be given by mouth or through an IV.

  • Stopping certain medicines or starting new ones. They include:

    • Medicines to lower blood pressure.

    • Antibiotics to treat infection.

    • Corticosteroids to reduce swelling and suppress the body’s defense system (immune system).

  • Dialysis or renal replacement therapy (continuous renal replacement therapy, CRRT). This treatment uses a machine to do the job of the kidneys.

  • Diet changes. Your child may need to:

    • Increase fluids.

    • Eat less food that contains protein, sodium, potassium, and phosphorus.

    • Receive special nutrition through an IV.

  • Surgery to remove a blockage in the urinary tract.

Follow these instructions at home:


  • Give you child over-the-counter and prescription medicines only as told by your child’s health care provider.

  • If your child was prescribed an antibiotic medicine, give it as told by his or her health care provider. Do not stop giving the antibiotic even if your child starts to feel better.

  • Do not give your child new medicines without the health care provider’s approval. Many medicines can worsen kidney damage.

  • Do not give any vitamin and mineral supplements without the health care provider’s approval. Many nutritional supplements can worsen kidney damage.


  • Make changes to your child’s diet as told by your child’s health care provider.

  • Have your child start or continue an exercise plan. He or she should exercise at least 30 minutes a day, 5 days a week.

  • Help your child achieve and maintain a healthy weight. If you need help with this, ask your child’s health care provider.

General instructions

  • Keep track of your child’s blood pressure. Report changes as told by the health care provider.

  • Keep your child up to date with vaccines. Ask the health care provider which vaccines your child needs.

  • Keep all follow-up visits as told by your child’s health care provider. This is important.

How is this prevented?

  • Have your child drink enough fluids to keep his or her urine pale yellow.

  • If your child has an infection, let him or her get treatment early.

  • Make sure your child is closely monitored if he or she is taking medicines that may be dangerous for the kidneys.

Where to find more information

  • American Association of Kidney Patients:

  • National Kidney Foundation:

  • American Kidney Fund:

  • Life Options Rehabilitation Program:



Contact a health care provider if your child:

  • Has symptoms that do not improve.

  • Has symptoms that are getting worse.

  • Has a fever.

Get help right away if your child:

  • Is younger than 3 months and has a temperature of 100.4°F (38°C) or higher.

  • Has pain in the abdomen or back.

  • Develops symptoms of worsening kidney disease, which include:

    • Confusion, loss of alertness, or memory loss (altered mental status).

    • Headaches.

    • Abnormally dark or light skin.

    • Bruising.

    • Frequent hiccups.

    • Shortness of breath.

    • Chest pain.

    • Seizure.

  • Is producing less urine.

  • Has pain or bleeding when he or she urinates.


  • Acute kidney injury is a sudden worsening of kidney function. This leaves the kidneys unable to remove waste and extra fluid from the body.

  • This condition may be caused by a drop in blood or oxygen flow to the kidneys, injury to the kidneys, or a blockage in the urinary tract.

  • Signs of this condition include reduced urination, swelling in the legs, ankles or feet, or around the eyes, nausea and vomiting, or unusual tiredness.

  • This condition is treated with fluids, medicines, dialysis, diet changes, or surgery.

  • Follow instructions about your child’s medicines, diet, and follow-up visits. This is important.

This information is not intended to replace advice given to you by your health care provider. Make sure you discuss any questions you have with your health care provider.