Pyelonephritis

Pyelonephritis is a kidney infection that happens when bacteria travel up from the bladder. It can make you feel very unwell, with symptoms like fever, back pain, nausea, and pain when peeing. It’s more serious than a regular urinary tract infection (UTI) and needs medical treatment, usually with antibiotics. If it’s not treated, it can cause serious problems like damage to the kidneys or septicaemia (blood poisoning). 

The symptoms of a kidney infection can come on suddenly and may include:

• Fever and chills.
• Pain in your lower back or side (usually on one side).
• Pain in your lower belly.
• Nausea or vomiting.
• Pain or a burning feeling when peeing.
• Feeling the need to pee more often.
• Cloudy, dark, or bad-smelling urine.
• Blood or pus in your urine.
• Feeling tired or unwell.

Older adults might not have the usual symptoms of a kidney infection. Instead, they may feel confused or suddenly seem different mentally. If this happens to you or someone you care about, it’s important to see a doctor right away.

A bad kidney infection, or having kidney infections often, can hurt your kidneys and cause long-term kidney problems.

The treatment for a kidney infection usually involves one or more of the below. 

If kidney infections keep coming back, they can damage your kidneys over time. The repeated infections may cause scars on your kidneys, making them not work as well. This can lead to long-term kidney problems. It’s important to treat the infections quickly to avoid more damage.

Is there anything else that can help stop kidney infection from coming back?

There isn’t much strong evidence that changes in your daily routine (lifestyle changes) work, but some people find these tips helpful:

• Drink lots of water throughout the day to help flush out bacteria.
• Wipe from front to back after using the toilet.
• Go to the bathroom when you feel the need to pee, instead of holding it.
• Pee right after sex.
• Take showers instead of baths and wash yourself every day.
• Try not to use products that can irritate your genital area, like soap, deodorants, powders, or gels used for birth control.

The information provided here is general and may vary based on where you live. You may want to ask your doctor for advice that's specific to your situation.

Here are some simple questions to ask your doctor about kidney infections:

• What caused my kidney infection?
• What treatments are there, and which one is best for me?
• How long will it take for me to feel better with treatment?
• Are there any other problems I should worry about?
• How can I keep kidney infection from happening again?
• Are there any lifestyle changes I should make to help me get better?
• Are there any side effects from the medicine I’m taking?
• How can I tell if the infection is getting worse or if I need to see you again?
• Can a kidney infection cause permanent damage to my kidneys?
• Do I need any tests to check for other problems caused by this infection?

These questions can help you understand your condition and get the right care.

This chapter contains general information about pyelonephritis. If you have any specific questions about your own medical situation you should consult your doctor or other professional healthcare provider. No website or leaflet can replace a personal conversation with your doctor.

Last updated: February 2025