Diagnosing kidney infection 

To work out if you have a kidney infection, your GP will ask you about your symptoms and your recent medical history.

They will usually also assess your general health by taking your temperature and measuring your blood pressure.

Urine test

A urine test can help to establish whether you have a urinary tract infection (UTI). The test involves taking a small sample of urine and checking it to see if there are any bacteria in it.

However, a urine test can't tell whether the infection – if you have one – is in your kidneys or another part of your urinary system, such as your bladder.

For your GP to be confident that you have a kidney infection, you need to have a positive urine test plus certain distinctive symptoms, such as a fever or a pain in your side.

Hospital scans

You may be referred to a hospital for further testing if:

  • your symptoms fail to respond to treatment with antibiotics
  • your symptoms suddenly get worse
  • you have additional symptoms that aren't usually associated with a kidney infection
  • you're prone to complications of a kidney infection

In these circumstances, scans can check your urinary tract for signs of problems. These include:

  • a computer tomography (CT) scan, where a scanner takes a series of X-rays and a computer is used to assemble them into a detailed image of your urinary tract
  • an ultrasound scan, which uses sound waves to build an image of the inside of your body
  • an isotope scan, where a dye is injected into the bloodstream and a series of X-rays are taken

Read more about treating a kidney infection.

Handing in a urine sample

If your GP asks for a urine sample, you'll be given a container and told how to collect the urine.  

You can do this in the surgery or at home. 

When you've collected the sample, screw the lid of the container shut, label it with your name, date of birth and the date, then wash your hands thoroughly. 

If you're at home, put the container in a  plastic bag, seal it and keep it in the fridge.

Ideally, hand the sample in at the surgery within four hours. 

Read more about how to collect and store a urine sample.

Page last reviewed: 11/12/2012

Next review due: 11/12/2014