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Kidney Biopsy

A biopsy is necessary to help in the diagnosis and/or treatment of your child’s kidney condition.

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How is the biopsy done?

The biopsy is done using a special needle to obtain a piece of kidney tissue. With your child lying on the tummy, ultrasound is used to find the kidneys. Almost all conditions requiring biopsy involve both kidneys and thus one will be chosen for biopsy. Using the ultrasound the lower part of one kidney is marked for best placement of the needle. Your child's back will be washed and draped and the needle guided to the surface of the kidney using the ultrasound. Usually 2 or 3 pieces of kidney tissue are obtained in this manner.

Will my child be awake during the procedure?

The degree of sedation necessary for the biopsy varies for each patient. Most kidney biopsies are done with the aid an anesthesiologist and done with your child asleep. The anesthesiology team will let you know whether your child is allowed to eat or drink the night before the procedure, and review the medications if your child is on any.

Who will be doing the biopsy?

Either a nephrologist or an interventional radiologist will be doing the biopsy. An ultrasound technician will be assisting with the procedure.

Who will be monitoring my child during the biopsy?

Depending upon the type of analgesia necessary, a nurse or anesthesiologist will be monitoring your child during the biopsy. Your child's breathing, heart rate and blood pressure will be constantly assessed during the procedure, like any other procedures requiring sedation.

What are the potential complications?

The major risk of the biopsy is bleeding. Kidneys receives about 20% of all the blood pumped out of the heart, and putting a needle in the kidney will cause some bleeding. Fortunately, the amount of bleeding is usually modest. Approximately 1 in 500 children will have enough bleeding after the biopsy to require a blood transfusion. However, those children usually have additional risks of bleeding.

Sometimes the urine will be bloody urine after the biopsy. However, it only needs a few drops of blood to make urine look pink or red. This usually clears within a few hours. More significant bleeding can occur around the kidney and is generally seen on ultrasound after the biopsy is done. In any case, your child will be monitored carefully for several hours after the biopsy for signs of bleeding.

It is important for you as a parent or guardian to understand that the biopsy is not risk-free, but that your child's doctor believes the benefits obtained are greater than these risks. You will be asked to sign a consent form for the biopsy. Please read this carefully and ask any questions before the procedure.

How will my child be monitored after the biopsy?

Your child's breathing, heart rate, and blood pressure will be carefully monitored after the biopsy by a nurse. All urine will be carefully evaluated for blood. Any problems will prompt the nurse to notify your doctor. When your child is fully awake, he or she will be allowed to eat and drink. The patients can go to the bathroom with assistance, but otherwise should remain in bed for at least 6 hours. If all vital signs are stable and urine clear (or unchanged in children with bloody urine before the biopsy) your child may be discharged home. If the biopsy is done late in the afternoon or there are any concerns, your child will stay overnight in the hospital for close observation.

What activities are allowed after we get back home?

For 2 days after the biopsy your child's activities should be limited to sitting, lying down and going to the bathroom. If there are no problems after 2 days, you child may return to school. However, he or she should not participate in physical education activities at school for 2 weeks. Similarly, your child should refrain from all significant physical activities for 2 weeks no jogging, bike riding, competitive sports, or other such activity.

When will we have the results?

The complete biopsy results will be known within approximately one week. Prior to discharge after biopsy, your doctor will discuss follow-up, including discussion of results and plans of treatment if they are indicated based on the biopsy results.