Symptoms of kidney infection 

The symptoms of a kidney infection usually develop quite quickly over a few hours or days.

Common symptoms include:

  • pain in your side
  • pain and discomfort in your lower back and around your genitals
  • high temperature (it may reach 39.5ºC or 103.1ºF)
  • shivering
  • chills
  • feeling very weak or tired
  • loss of appetite
  • feeling sick
  • being sick
  • diarrhoea

You can also have other symptoms if you also have cystitis or urethritis (an infection of the urethra). These additional symptoms may include:

  • pain or a burning sensation during urination
  • the need to urinate frequently or urgently
  • feeling that you're unable to urinate fully
  • blood in your urine
  • cloudy or foul smelling urine
  • pain in your lower abdomen


Children with a kidney infection may also have additional symptoms such as:

  • a lack of energy
  • irritability
  • poor feeding and/or vomiting
  • not growing at the expected rate
  • abdominal pain
  • jaundice (yellowing of the skin and whites of the eyes)
  • blood in the urine
  • unpleasant smelling urine
  • bedwetting

When to seek medical advice

Contact your GP if you have a high temperature, persistent pain, or if you notice a change to your usual pattern of urination. Contact your GP immediately if you think your child may have a kidney infection.

If you have blood in your urine, you should always see your GP so that the cause can be investigated.

Kidney infections require prompt treatment with antibiotics to help relieve symptoms and prevent complications developing.

Your GP can carry out some simple tests to help diagnose a kidney infection.

See diagnosing kidney infections for more information.

If you have a kidney infection

Make sure that you get plenty of rest. A kidney infection can be physically draining, even if you're normally healthy.

It may take up to two weeks before you're fit enough to return to work.

Page last reviewed: 11/12/2012

Next review due: 11/12/2014