Pyelonephritis is the medical name for a kidney infection. It is an unpleasant illness that is usually caused by a urinary tract infection or cystitis - a common bladder infection. Most people with either a UTI or cystitis will not get a kidney infection, but occasionally the bacteria can travel up the urinary tract to one or both kidneys.  

Symptoms of a kidney infection often come on within a few hours. You may feel feverish, nauseous, and have a pain in your back or side. Symptoms from a UTI can include needing to pee suddenly or more often than usual, pain or a burning sensation when peeing, smelly or cloudy pee or blood in your pee.

A kidney infection is usually cased by bacteria, most commonly a type called E. coli. The bacteria gets into the urethra, the tube that carries urine out of your body, it then travels up to your bladder where it can cause UTI’s such as cystitis, and the up to your kidneys. E. Coli bacteria normally lives in your bowel, where it causes no harm. The bacteria can be transferred from your bottom to the genitals during sex, or after going to the toilet if you are not careful. Other kidney problems, such as kidney stones, diabetes, or a weakened immune system can also cause a kidney infection.

You should see a doctor if you have pain in your tummy, back or genitals that will not go away. Most kidney infections need quick treatment with oral antibiotics to stop the infection damaging the kidneys or spreading into the bloodstream. Oral painkillers may also be required. It is important to take the medication as directed by your doctor to ensure they work properly.

To prevent a kidney infection, it will help to drink plenty of fluids (plain water is best), going to the toilet as soon as you feel the need to pee, rather than holding it in. Going to the toilet after sex, wiping from front to back after going to the toilet and washing your genitals every day.