At hospital

Your child will go back to the hospital ward to rest in bed, usually for about 6 hours. After a biopsy, children often need to lie flat for 2 hours and then sit up for 4 hours – this helps avoid bleeding from their kidney.

On the hospital ward after the biopsy

  • If your child has had general anaesthetic or sedation, he or she may feel drowsy for a little while, as they “wake up”.
  • Your child can read or look at books, do homework, or play with toys – as long as they stay resting.
  • Your doctor will let you and your child know what he or she can eat and drink.

A team of healthcare professionals will monitor your child after the biopsy to make sure they are recovering well.

A team of healthcare professionals will monitor:

  • your child’s heart rate
  • his or her breathing
  • his or her blood pressure
  • the biopsy site – to see that it is not bleeding
  • that your child is eating and drinking
  • that your child is passing urine (weeing)

The urine that your child passes will be collected in a pot, and the nurse will test it for blood.

Going home

If your child is well after the biopsy, has no complications, and no or little blood in his or her urine, he or she can probably go home about 6 hours after the procedure.

If the biopsy took place late in the afternoon, your child may need to stay overnight and go home the following morning.

Recovering at home

Blood in the urine

Your child’s healthcare team will have checked for any blood in his or her urine. Some children will continue to have a little blood in their urine after they get home – the urine may be dark brown (like a cola drink) or red (like Ribena).

This should stop after a day.

If your child continues to have visible blood in his or her urine after 24 hours, contact the hospital.


Keep the dressing dry and in place for 2-3 days after the biopsy. This will help it to heal. The scar from the needle is very small.

Other medicines

Check with your doctor or pharmacist before giving any other medicines to your child, for a few weeks after the biopsy. This includes herbal and complementary medicines, and medicines that you can get over the counter.

School and nursery, and sport

Your hospital staff will give you more information about when your child can go back to school or nursery – this is usually after 2 days – and start doing their usual activities. Often your child will need to avoid running around or riding a bike for 1 or 2 weeks, and avoid contact or impact sports for up to 4 weeks – these include rugby, football, jumping on a trampoline or horse riding.

Call the ward if

  • your child complains that the biopsy site is very painful – for example, if normal pain relief is not helping and your child is unable to play, get up or walk in the days after they go home
  • you can see blood, or blood clots, in your child’s urine
  • there is any oozing or bleeding from the biopsy site, or if it becomes red
  • your child cannot wee
  • your child gets a fever (temperature above 38°C)
  • your child feels faint or dizzy.

Examination and results

It can take several weeks to get the full results because of the different ways in which the kidney samples are examined. The amount of time depends on your hospital. 

The results will give your doctor more information to help them give a diagnosis or find out the best treatment for your child. Your doctor will let you know about a follow-up visit to talk about the biopsy results and what they mean.

How the kidney sample is examined

The small pieces of kidney that are removed in a biopsy must contain several glomeruli and one or more arteries, a type of blood vessel. The glomeruli are like the tiny filters of the kidney. They are in the outer part of the kidney, which is called the renal cortex. Because the kidneys have about one million glomeruli, just taking several from one kidney will not affect how it works.

Hospital staff will look at the sample from your child’s kidney in three stages. 

  • Light microscopy – first, the sample is looked at under a microscope, usually within 1 or 2 days of the biopsy.
  • Immunofluorescence – next, a special stain is added to the sample to show any chemicals that may be harming the kidney – this usually happens within several days.
  • Electron microscopy – a special, large microscope called an electron microscope is used to see the glomeruli in fine detail – this usually happens within several weeks.

Readmission for another biopsy

Occasionally, the doctor is not able to get a good enough sample for the biopsy to make a diagnosis. If that is the case, your child may need another biopsy. Your doctor will explain what should happen next.