Pyelonephritis
A kidney infection (pyelonephritis) is a painful and unpleasant illness caused by bacteria travelling from your bladder into one or both of your kidneys
The symptoms of a kidney infection usually develop quite quickly over a few hours or days.
A kidney infection happens when bacteria enters and infects one or both of your kidneys.
To work out if you have a kidney infection, your GP will ask you about your symptoms and your recent medical history.
Most people with a kidney infection can be treated at home by taking a course of antibiotics, and possibly painkillers as well.
Most kidney infections are treated successfully without any complications, although some people may develop further problems.
The best way to prevent a kidney infection is to keep your bladder and urethra free from bacteria.