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Kidney injuries



Each person has two kidneys, which are located on either side of the spine, behind the intestines and just above the waist.

The kidney cleans the blood by filtering out waste materials and getting rid of any water the body doesn't need. The liquid waste made by the kidneys is called urine. The kidneys are part of the renal system. The renal system also includes the ureters, bladder and urethra.

Urine is made in the kidneys and it passes through the ureters. The ureters are small tubes that connect the kidneys to the bladder. The bladder stores the urine. The urine then goes from the bladder through a tube called the urethra to the outside of the body.

Signs & symptoms

Renal or kidney injuries in children are usually minor. A child's kidney is more likely to be injured than an adult's kidney because there is less protection from the bones and muscle around it.

The most likely cause of renal injuries is motor vehicle crashes. A hard blow to the upper abdomen or back such as from a fall, sports injury or violent act can cause injury to the kidney or bladder as well.

A kidney injury may also result from a gunshot wound or knife wound that tears and cuts the organ. These types of injuries are known as penetrating injuries.


Children with renal injuries may have bruising, pain in their back, or there may be no marks at all.

If renal injury (an injury involving, affecting, or located in the region of the kidneys) is suspected, your child will be given a physical examination. A urinalysis (urine test) will test if there is blood in the urine. X-rays, CAT scan (a picture with more detail than an X-ray), and ultrasound (special test that shows pictures of the kidney) or blood tests may be done to determine how badly your child's kidney is damaged.

Kidney injuries are graded based upon the information received from testing. Grade 1 kidney injuries are the least serious, while Grade 5 injuries are the most serious.


Most kidney injuries do not require surgery. A child with a small injury to the kidney will go to the general care unit for a few days of strict bed rest. Children with major kidney injuries may go to the ICU (Intensive Care Unit) for a day or two on strict bed rest and then to the general care unit. The urologist (kidney doctor) may also be caring for your child when the injury to the kidney is serous.

Decreasing the amount of bed rest and increasing the child's activity level will happen gradually as the child's injury heals. Each child is different in the time required to heal.

If a child's kidney is badly damaged, surgery may be needed to fix the damage and to stop the bleeding. The surgical incision may be closed with small metal staples or stitches. The child may need some extra blood before or after surgery. He or she will also not be allowed to eat right away. However, the child will receive fluids through an IV (a small tube in their vein). The child will be closely monitored and cared for in Children’s Intensive Care Unit after surgery for a few days for any bleeding, pain, or infection. The child is then transferred to the general care unit as healing continues.

After discharge

After you leave the hospital, your child will need to be watched for any problems. Complications do not happen very often but as a precaution, you should be able to recognize warning signs and symptoms.

You will need to call your doctor right away if your child has:

  • Any blood in the urine
  • Fever greater than 100.5 degrees
  • Belly pain and tenderness

Medications and pain

Speak to your healthcare provider about medications your child has previously taken. Your child may have some pain or soreness at home.

Give acetaminophen (also known as Tylenol) for pain. Your child's doctor may write a prescription for stronger pain medication. First administer Acetaminophen and if the pain does not go away one hour after giving acetaminophen, give the prescription pain reliever. Follow the directions on the bottle.

However, do not give your child ibuprofen (also known as Motrin, Advil, Aleve, etc.) until the doctor says that it is OK.

Wound and skin care

Your child may shower or take a bath, but he or she may need help for several days after going home. Check with your doctor about taking baths if your child has had surgery.

If your child has cuts or scrapes on the skin from other injuries, wash the areas with warm, soapy water and pat dry. If your child has stitches or staples, follow the specific instructions for caring for them.

Emotional recovery

After the injury, your child may be tired and irritable. It takes time to heal. Use this time for rest and quiet activities. Tell your child that they will feel better soon. Have your child play board games, read, or do small craft projects for short periods of time.

Infants and toddlers are harder to distract and will be more difficult to confine. Try putting your infant or toddler in a large crib or playpen. Ask family and friends to visit, but for short periods of time and not at the same time to minimize activity.

Preventive action

It is very important to teach your child about all types of safety. Your child watches you and will tend to do what you do. You should always practice proper safety precautions. Your child should learn to wear a helmet when riding a bike, in-line skating or skate boarding.

You should also teach your child to always wear a seatbelt when riding in a car. Remember that children 12 years and younger should wear correct safety restraints in the back seat when the car has a passenger side airbag.


All children with kidney injuries are seen in either the Trauma / Surgery Clinic or Urology Clinic about two weeks after they leave the hospital. Your doctor will decide then whether your child will need follow-up testing. Your child may need a pediatrician to monitor his or her blood pressure.


Your child may not feel like eating regular foods right away, but it is important to eat a balanced diet and drink as much fluid as before he / she was hurt.

Activity after a kidney injury

Plan quiet activities for the first several days at home. Your child does not need to stay in bed, but should walk and play quietly. Your child should not play rough with family, friends, or pets. He or she should not participate in any activities or sports that involve jumping, climbing, or running such as bike riding, in-line skating, dance, gymnastics, football, basketball, soccer or track. Activities like gym class and contact sports are not allowed for some time after leaving the hospital. Returning to such activities will depend on the grade of injury.

Your child can go back to day care or school usually one to two weeks after the injury. Your nurse or doctor will help you decide when it is time to send your child back to school.

If surgery was needed or your child has other injuries, he or she may be out of school longer. The trauma team will help you with your child returning to school. At school, your child should not be taking gym class until the doctor says it's OK. It's best for your child to leave class five minutes before the other students, to avoid bumping into children in the halls. Your child should not carry or lift more than one to two textbooks at a time, even if carrying a book bag or backpack.

UCSF Benioff Children's Hospitals medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your child's doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your child's provider.

Where to get care (2)


Trauma Care Center

Trauma Care Center

747 52nd St.
Oakland, CA 94609

emergency-room-er-320x320-2x 2

Emergency Department

Emergency Department

San Francisco / Oakland

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