How to Treat It and What to Know

Bacteria from a urinary tract infection (UTI) can travel into the kidneys and cause an infection. Back pain can be a symptom of a kidney infection. The pain can appear in the lower or upper back or on either side. 

A UTI occurs when bacteria, sometimes from the skin or rectum, get into the urinary tract, kidneys, bladder, or urethra. Approximately 60% of people assigned female at birth and 12% of people assigned male at birth will have at least one UTI in their lives. 

There are different types of UTIs, including:

Pyelonephritis occurs when bacteria spread into the kidney from the bloodstream. Pyelonephritis is less common, but it can cause back pain and can be a serious health condition. 

This article discusses back pain as a symptom of a UTI or kidney infection, treatments, and more.

Back pain is not usually a symptom of a UTI. However, back pain can be a symptom of a kidney infection resulting from a UTI. 

Inflammation of the kidneys can cause pain in the back or on either of the sides. The pain may continue or worsen until you take a course of antibiotics. With antibiotics, you may start to feel better after 24 hours. You may feel completely better after 2 weeks. 

Learn about other causes of back pain.

Your doctor will likely prescribe antibiotics if you have a UTI or kidney infection. They may also recommend strong pain relief medications.

Your doctor may also suggest:

• drinking plenty of water
• taking nonsteroidal anti-inflammatory drugs
• using a heating pad to ease pain 

Learn more about treatments for kidney infections.

The main symptoms of a kidney infection are back pain and fever. Other symptoms may include:

• nausea
• vomiting
• burning or stinging feeling when urinating
• increased need to urinate
• cloudy or foul-smelling urine
• blood in the urine

These symptoms may start within a few hours or over the course of a 24-hour period. 

Learn more about the symptoms of pyelonephritis.

It is important to contact your doctor as soon as you think you may have a UTI. This is to prevent it from developing into a kidney infection. 

If you already have a kidney infection, it is important that you start treatment as soon as possible. If not treated, a kidney infection can cause lasting kidney damage or spread to other parts of the body. 

Contact your doctor if you have any of the following symptoms:

• fever 
• constant pain in the stomach, lower back, side, or around the genitals
• changes in your urination pattern

Find out more about when to see a doctor for a UTI.

In order to confirm the diagnosis, your doctor may carry out tests including:

• urine test, to look for bacteria 
• blood test 
• ultrasound scan 
• CT scan 
• isotope scan 

Risk factors for a UTI include:

• history of UTIs
• being sexually active
• bacterial changes inside the vagina resulting from menopause or the use of spermicides
• pregnancy 
• difficulty maintaining personal hygiene
• older age 
• having an enlarged prostate 

Risk factors for a kidney infection include: 

• having a current UTI 
• having had a UTI in the past year
• being a person assigned female at birth 
• pregnancy
• blockages in the urinary tract that stop the flow of urine
• a weakened immune system
• struggling to fully empty your bladder 
• having diabetes

If you have a UTI and are experiencing back pain, it may be a sign of a kidney infection. This can be serious and may require urgent medical attention.

It can take from a few hours to 24 hours for a UTI infection to become a kidney infection.

You may have a kidney infection if you begin to experience lower or upper back pain, pain on your sides, fever, nausea, or vomiting. It is important to contact your doctor for advice if this is the case.

If you do not receive treatment for a UTI, it may develop into a kidney infection. Back pain can be a symptom of a kidney infection.

Your doctor may prescribe antibiotics for a kidney infection. You can also use pain relief medication to help manage back pain.

If you think you may have a kidney infection, contact your doctor for advice. Left untreated, a kidney infection can become life threatening. Your doctor can recommend treatments for the infection and advise you on managing the pain.