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Pyelonephritis: A Comprehensive Overview

Urinary tract infections (UTIs) can be uncomfortable, painful, and, for many women, all too common. There’s a certain kind of kidney infection called pyelonephritis that can be especially nasty. If you suffer from chronic UTIs, read on for more information about this condition.

Acute pyelonephritis is one of the most common kidney diseases, but that doesn’t mean it can’t be serious. This illness begins as a bacterial infection, travels through the urinary tract, and gets into the kidneys. Kidney infections from a UTI result in over 100,000 hospital visits in the United States each year.

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Pyelonephritis begins as a typical UTI caused by bacteria, most commonly E. coli, although other kinds of bacteria can reach the urinary tract from the skin around the genitals. It’s one of the main causes of kidney infection and can be especially dangerous if a woman is pregnant, resulting in pregnancy complications like preterm birth.

With this condition, the kidneys become inflamed and painful. Left untreated, chronic pyelonephritis can lead to kidney dysfunction and kidney failure.

The most recognizable symptom of pyelonephritis is urine that smells bad or is cloudy. Many people report a burning or itching sensation when they pee and feel the urge to go more strongly. Any time you feel pain when you urinate, you should seek medical advice. A simple bladder infection can usually be treated with a round of antibiotics, but those symptoms could also indicate a sexually transmitted infection.

Left untreated, bladder infections can quickly spread to your kidneys. Typical symptoms of acute pyelonephritis can include:

  • Fever and chills
  • Pain in the lower back, on one or both sides, or pain in the pelvic region
  • Nausea and vomiting — Often, patients with acute pyelonephritis experience loss of appetite and have trouble keeping food down.
  • Pus or blood in your urine
  • Frequent, painful urination
  • Foul-smelling, cloudy urine
  • Chronic fatigue

If you have a kidney infection and are exhibiting these symptoms, you need to seek immediate medical attention. It’s also important to note that very young children (under 3 years old) and the elderly (65 and older) have different symptoms with a kidney infection.

Young children may only develop a high fever, sometimes as high as 103 degrees Fahrenheit or more. They, too, may experience nausea and vomiting and difficulty eating. When your child is potty training, it’s important to help with wiping and cleaning to keep E. coli bacteria from their stools from reaching their urethra.

Elderly patients with a bladder or kidney infection may experience different symptoms as well. If a UTI reaches the kidneys, seniors may have difficulty focusing or concentrating and may have jumbled speech. They may also experience confusion and hallucinations or possible complications in another organ system. For older people with incontinence issues or who require adult diapers, cleanliness is also important to prevent bacteria from their stools reaching the bladder.

Typically, an untreated bladder infection is the cause of a kidney infection. Other causes of a kidney infection include:

  • Having urinary tract blockages, such as a kidney stone or unusually configured urethra, that slow the flow of urine from your body — An enlarged prostate gland can contribute to blockage, although enlarged Skene glands (or “female prostates”) don’t usually have this effect.
  • A compromised immune system, such as from diabetes, HIV, chemotherapy, or another treatment that affects your body’s ability to ward off infection — If you’re the recipient of an organ transplant, certain anti-rejection medications may also compromise your immune system.
  • Being female, especially if you’re pregnant — Because women have shorter and wider urethras, there’s less distance for the bacteria to travel into the bladder. Plus, the vagina and anus are all very close to the opening of the urethra, making the chances of bacteria ending up there greater.
  • Use of a urinary catheter — Catheters are tubes that drain urine from your bladder through the urethra into a collection bag. They’re common after surgery, such as a C-section, or may be used for patients on bed rest.
  • Nerve damage to the bladder and nerves around it. Certain spinal cord injuries can block the pain sensations associated with a bladder or kidney infection, which can make you unaware that you have an infection.
  • More rarely, a condition called vesicoureteral reflux causes urine to flow the wrong way. With this condition, small amounts of urine flow from the bladder back into the kidneys.

When you visit your doctor, they’ll examine you and ask about your history with bladder infections and your symptoms. Expect an external exam, where the doctor will feel for tenderness or swelling, and possibly a pelvic exam to rule out a sexually transmitted infection.

The doctor will also probably ask you for urine and blood samples. These will be examined for bacteria and inflammation, as people who have acute pyelonephritis will have bacteria in their urine and signs of inflammation in the blood sample. This can indicate how advanced your kidney infection is. The cultures taken from your blood and urine can also be used to assess whether the infection may be antibiotic-resistant.

Further testing could include imaging scans, for example a CT scan, MRI, or ultrasound, to detect hemorrhaging, inflamed masses, urinary tract obstructions, and other indications that the infection has compromised the kidneys.

Initial treatment for this infection is typically antibiotics, with a follow-up examination after you’ve completed the course. Expect to give additional blood and urine samples at this point. The antibiotics should help prevent the progression of kidney infection. This is usually successful for milder cases, and treatment is provided on an outpatient basis.

More severe cases of pyelonephritis require hospital care. Doctors will monitor your blood and urine (expect to give repeated samples while in the hospital) and check your other body systems to ensure that the infection isn’t spreading. You may also receive intravenous fluids for hydration or antibiotics.

In the most severe cases, or in cases where the pyelonephritis has been especially aggressive, you may be recommended for surgery to remove abscesses in the kidney area or drain extra fluid from the renal (kidney) area.

Prevention can also be key to reducing your risk for developing pyelonephritis, and many of these preventive options are part of overall treatment for the illness. These include:

  • Drink plenty of water, at least 64 ounces per day. Besides preventing dehydration, water also helps your kidneys flush out infection-causing bacteria and reduces your risk of kidney stones.
  • Wipe from front to back when using the bathroom to reduce fecal bacteria entering your urinary tract.
  • Don’t forget to pee after sex. After intercourse, urinating helps flush bacteria from the bladder.

Complications from a kidney infection can be severe and sometimes even life-threatening. Abscesses can form around or inside the kidneys, which may lead to kidney scarring, chronic kidney disease, or kidney failure. Untreated infections may also lead to blood poisoning. The kidneys filter waste from your blood, and bacteria in the kidneys can transfer back out, traveling to other organs in your body.

For pregnant women, a kidney infection may increase the risk of delivering a low-birth-weight baby or preterm delivery.

Any time you feel pain when urinating, your urine looks cloudy or smells bad, or there’s blood in it, it is better to see a doctor. If caught early enough, a bladder or kidney infection can usually be treated with a round of antibiotics. However, because the symptoms of a bladder infection are often similar to symptoms of sexually transmitted infections, it’s a good idea to protect your reproductive health with a comprehensive exam. 

Acute pyelonephritis is a bacterial infection of the kidneys that can have life-threatening complications. It occurs as a consequence of an untreated bladder infection and can lead to kidney disease or failure. If you are showing the symptoms we’ve discussed, it is better to visit your doctor.

https://emedicine.medscape.com/article/245559-overview

https://www.niddk.nih.gov/health-information/urologic-diseases/kidney-infection-pyelonephritis/symptoms-causes

https://www.mayoclinic.org/diseases-conditions/kidney-infection/symptoms-causes/syc-20353387

https://www.ncbi.nlm.nih.gov/books/NBK519537/

https://www.health.harvard.edu/a_to_z/pyelonephritis-a-to-z

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