Medically Reviewed By William C. Lloyd III, MD, FACS
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What is pyelonephritis?

Pyelonephritis is a kidney infection. It is usually bacterial in origin and stems from an infection in another part of the urinary tract, such as the bladder. Pyelonephritis can occur in anyone, although it is more likely to occur in women.

Symptoms of pyelonephritis include pain or burning during urination, an urgent need to urinate, fever, nausea with or without vomiting, hematuria (blood in the urine), and pain, particularly in the sides and groin. Left untreated, pyelonephritis can lead to further kidney infections, scarring, chronic kidney disease, or permanent damage. Serious infections can spread to other parts of the body, including the blood (sepsis).

Pyelonephritis is easily diagnosed with a physical examination and urine tests. In cases of bacterial infection, pyelonephritis can be treated with antibiotics. For mild pain with pyelonephritis, home remedies, including heating pads, may be helpful. Fluid therapy and pain medications may also be administered as needed. Any permanent damage caused by pyelonephritis may require surgery.

Preventing urinary tract infections may be the best way to prevent pyelonephritis. Good personal hygiene is critical in preventing urinary tract infections.

Seek immediate medical care (call 911) for serious symptoms of pyelonephritis, such as a high fever (higher than 101 degrees Fahrenheit), fainting or change in level of consciousness, severe or uncontrolled pain, or persistent vomiting.

Seek prompt medical care for painful or persistent symptoms of pyelonephritis, such as painful or frequent urination.

What are the symptoms of pyelonephritis?

Symptoms of pyelonephritis occur due to infection of the kidneys and include pain, problems with urination, and other symptoms of general infection.

Common symptoms of pyelonephritis

You may experience pyelonephritis symptoms daily or only occasionally. Any of these symptoms can be severe:

Symptoms that might indicate a serious condition

In some cases, pyelonephritis can be a serious condition that should be immediately evaluated in an emergency setting. Seek immediate medical care (call 911) if you, or someone you are with, have any of these serious symptoms including:

  • Confusion or loss of consciousness for even a brief moment
  • High fever (higher than 101 degrees Fahrenheit)
  • Inability to urinate
  • Persistent vomiting
  • Severe pain

What causes pyelonephritis?

Pyelonephritis results from an infection, generally bacterial, of the kidneys. Oftentimes, this infection spreads from the urinary tract to the bladder and progresses to the kidneys. Left untreated, it can lead to permanent damage. In very serious cases, the infection can spread to the bloodstream (sepsis).

What are the risk factors for pyelonephritis?

A number of factors increase the risk of developing pyelonephritis. Not all people with risk factors will get pyelonephritis. Risk factors include:

  • Diabetes (chronic disease that affects your body’s ability to use sugar for energy)

  • Enlarged prostate

  • Fecal incontinence (inability to control stools)

  • Hospitalization

  • Immobility

  • Immunocompromised health status

  • Kidney stones

  • Narrow urethra

  • Older age

  • Pregnancy

  • Previous bout of pyelonephritis

  • Problems voiding the bladder

  • Recent urinary tract infection

  • Surgery

  • Urinary catheter

Reducing your risk of pyelonephritis

The best prevention for pyelonephritis is obtaining prompt treatment for any urinary tract infection. You may also be able to lower your risk of pyelonephritis by:

  • Avoiding alcohol and caffeine

  • Avoiding tight-fitting pants

  • Avoiding undergarments made from synthetic materials

  • Avoiding use of scented products around the genital area

  • Bathing the opening of the urethra thoroughly and regularly

  • Drinking cranberry juice (unless you have kidney stones)

  • Drinking plenty of fluids

  • Seeing your doctor to treat urinary tract infections

  • Taking showers instead of baths

  • Urinating before and after sexual intercourse

  • Wiping from front to back after a bowel movement

How is pyelonephritis treated?

Pyelonephritis is generally treated with antibiotics. In addition to antibiotics, fluid therapy and medications to control pain and nausea may be used to treat symptoms of pyelonephritis.

Medications for pyelonephritis

Generally, oral antibiotic regimens are recommended for clearing uncomplicated pyelonephritis infections, as well as other medications including:

  • Antibiotics, such as amoxicillin, doxycycline, fluroquinolones, and trimethoprim-sulfamethoxazole

  • Medications to reduce fever or control nausea

  • Pain medications such as phenazopyridine hydrochloride

Other treatments for pyelonephritis

In addition to medication, other treatments for pyelonephritis may include:

  • Fluid therapy to replace fluids lost from excessive urination

  • Surgery for severe and permanent damage due to pyelonephritis

What you can do to improve your pyelonephritis

In addition to prescribed treatments, you may be able to improve symptoms of pyelonephritis, including pain, by:

  • Using home remedies such as heating pads
  • Using over-the-counter pain medication

What are the potential complications of pyelonephritis?

If promptly treated, pyelonephritis may clear without complications. Pyelonephritis is an infection, however, and this infection can spread and become very severe. Complications of untreated or poorly controlled pyelonephritis can be serious, even life threatening in some cases. You can help minimize your risk of serious complications by following the treatment plan you and your health care professional design specifically for you. Complications of pyelonephritis include:

  • Adverse effects of treatment

  • Kidney abscess

  • Kidney failure

  • Kidney scarring

  • Sepsis (life-threatening bacterial blood infection)

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Jan 18
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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