Kidney infection symptoms, common causes & treatments

If you have abdominal or side pain with a strong, persistent urge to urinate and are experiencing pain during urination, you may have a kidney infection.

While kidney infection causes are varied and anyone can get them, they are more common in women than men.

A kidney infection, which is a type of urinary tract infection (UTI), generally begins in your urethra (the tube that carries urine from your body) or bladder and travels to one or both kidneys.

Other kidney infection symptoms can include:

• Back or groin pain
• Frequent urination with little release
• Nausea and vomiting
• Pus or blood in your urine
• Foul-smelling urine

What causes a kidney infection?

The regular passage of urine usually flushes pathogens out of the urinary tract and prevents infections. Sometimes, however, bacteria can enter the urinary tract, causing a UTI that, if left untreated, can develop into a kidney infection. Usually, the infection is caused by bacteria in the bowel, most commonly E. coli bacteria. However, urethritis (inflammation of the urethra) can also occur due to sexually transmitted infections such as chlamydia and gonorrhea. In some cases, bacteria from an infection in another part of the body can enter the bloodstream to cause a kidney infection.

How does it differ from a urinary tract infection (UTI)?

To understand a kidney infection vs UTI, you must first understand how the urinary system works.

The main functions of the urinary tract are to extract, hold, and transport waste from your body in the form of urine. It’s comprised of:

• Two organs, located on either side of your body, filter out excess water and waste from your blood to create urine. They are the first part of the urinary tract.
• : Two thin tubes that transport urine from the kidneys to the bladder.  
• Bladder: Stores urine until it reaches a certain level, at which point you feel the need to urinate.
• Urethra: Thin tube that moves urine from the bladder to the outside of the body.

A kidney infection is a severe UTI, and the two conditions share some of the same symptoms, including:

• A painful or burning sensation when urinating
• Feeling like you need to urinate often
• Bad-smelling urine
• Cloudy urine or urine with blood in it
• Passing only a small amount of urine even though you have to urinate frequently
• Abdominal discomfort

A UTI may have moved into your kidneys if you experience the above symptoms as well as the following:

• Fever
• Chills
• Pain that’s localized in your lower back or side
• Nausea or vomiting

If left untreated, a kidney infection can lead to serious health complications, including kidney damage (and failure) or a life-threatening condition called sepsis.

Do men and women feel different symptoms?

Because of the female anatomy, women are more likely than men to develop a UTI. The female urethra is shorter and closer to the anus, which means bacteria have a shorter distance to travel in order to establish an infection. When a man gets a UTI, it is usually a more complicated condition commonly caused by an enlarged prostate or kidney stones. Both sexes experience the same uncomfortable UTI and kidney infection symptoms.

How do you treat a kidney infection?

To determine if you have a kidney infection, a doctor will analyze a sample of your urine. If you test positive for a kidney infection diagnosis, you’ll be prescribed antibiotics and, in some cases, a medication that helps relieve pain with urination. Your doctor can also have you tested for lupus since lupus is often a missed diagnosis and can have similar symptoms to kidney infection.

People with severe kidney infections may need to be hospitalized to receive antibiotics and fluids intravenously. While you may begin to feel better a day or two after starting antibiotics, it’s important to complete the entire course of prescribed medication to help prevent repeat infections.

After starting antibiotics, you can help alleviate kidney infection pain by taking over-the-counter pain medication. You can also try to ease the discomfort by trying several home remedies for kidney infections, including drinking plenty of water, using a heating pad, and taking vitamin C.

What is the best way to prevent kidney infections?

Although UTIs and kidney infections aren’t 100 percent preventable, there are several things you can do to reduce your risk:

• Regularly drink plenty of water to help flush your urinary tract. Cranberry juice can also help ward off UTIs.
• Eat a high-fiber diet, as constipation can lead to kidney infections.
• Perform pelvic exercises to help strengthen the bladder, which can prevent slow leaks that lead to bladder infections.
• Don’t “hold it.” Use the restroom as soon as you feel the need to urinate.
• Avoid using spermicide-coated condoms or diaphragms and choose lubrication to prevent pain and tearing that can lead to UTIs.

If you think you may have a UTI or kidney infection, visit your nearest urgent care, we're a team of healthcare professionals who can help diagnose and treat your symptoms.

Written by Sarah Thebarge, Physician Assistant