Key takeaways

• Kidney infections (pyelonephritis) are bacterial infections that can lead to serious complications and death.
  
• Common symptoms of kidney infections include high fever, pain during urination, lower back pain, and foul-smelling urine. Seek emergency care if you experience any of these symptoms at the same time.
  
• Risk factors for developing kidney infections include being female, urinary blockage, a weakened immune system, damage to the urinary system, and catheter use.
  
  
  

Kidney infections (pyelonephritis) are bacterial infections of the kidneys. If left untreated, these infections can cause serious health problems, even death. Because of this, a kidney infection requires urgent medical attention.

How can a kidney infection lead to death?

Kidney infections can cause serious complications such as kidney failure and death. They are bacterial infections that travel from the ureters to the kidneys. Here, the bacteria can multiply, making the infection more severe. Severe kidney infections may cause kidney damage or kidney failure. If kidney failure is not treated, it can lead to death within a few days or weeks.

If the infection moves from the urinary system to the bloodstream, a medical emergency known as sepsis may occur. Sepsis is an inflammatory response to an infection that can result in organ failure and death. You can die from sepsis within 12 hours of the earliest sign of infection.

Infections in the urinary system (which includes the kidneys) are responsible for 25% of sepsis cases. Between 30-40% of sepsis cases lead to death.

In addition to these two potentially life-threatening complications, kidney infections can cause serious complications, including:

• Renal abscess formation (pus-filled abscesses in the kidneys)
  
• High blood pressure
  
• Kidney scarring
  
• Chronic kidney disease
  
• Pregnancy complications (like low birth weight)
  
  

Because of the risk of these complications, you should seek medical attention at the first sign of symptoms.

What are the signs and symptoms of a kidney infection?

The early symptoms of a kidney infection are often similar to those of a urinary tract infection (like a bladder infection). Both conditions can seriously affect your health and should be treated immediately.

Kidney infection symptoms include:

• High fever
  
• Chills
  
• Pain during urination
  
• Frequent urination
  
• Lower back pain
  
• Blood or pus in the flow of urine
  
• Nausea
  
• Vomiting
  
• Foul-smelling urine
  
• Stomach pain
  
  

If you begin to notice any of the symptoms above, seek medical advice from a healthcare provider immediately.

What causes kidney infections?

Kidney infections often start out as lower urinary tract infections (UTIs) affecting the bladder or urethra. A bacteria (usually E. coli) infects the urethra (the passageway that carries urine out of the body) and travels up the urinary tractas lower urinary tract infections (UTIs) affecting the bladder or urethra. A bacteria (usually E. coli) infects the urethra (the passageway that carries urine out of the body), travels up the urinary tract, and infects theto theand infects the kidneys. This same process can also cause a bladder infection (cystitis).

Other causes of kidney infection but less common are bacteria entering the kidney through the bloodstream, urine flow blocked by kidney stones, urine flowing up into the kidney, catheters and surgery.

Kidney infections can happen to anyone. However, there are a number of risk factors that may increase your likelihood of developing a kidney infection.

Common risk factors include:

1. Gender: Women are more likely to develop kidney infections than men because their urethra is shorter. The urethra is also closer to the anus, which makes it easier for bacteria to pass between the genitals and cause infection. Pregnant women are at even greater risk of kidney infection than non-pregnant women due to their lower immune status.

2. Urinary blockage: Any blockage in the urinary tract, be it kidney stones, an enlarged prostate, or a narrowed urethra, can slow or stop the flow of urine. This can increase the risk of infection.

3. Weakened immune system: A weakened immune system can increase your risk of developing infections. People with health conditions like diabetes or HIV have been shown to beare at greater risk for developing kidney infections.

4. Damage to the urinary system: Structural or nerve damage to the urinary tract has been shown to increase your risk of developing a UTI or kidney infection.

5. Catheter use: People who use a urinary catheter (a tube that carries urine from the bladder) are at greater risk of developing a kidney infection.

6. Urinary tract conditions: Vesicoureteral reflux, a rare condition in which urine flows backward from the bladder and into the kidneys, can increase one's risk of kidney infections.

Less common causes of kidney infection are bacteria entering the kidney through the bloodstream or infections from an artificial joint or implanted medical device.

When should I see a doctor about a kidney infection?

In some cases, a kidney infection might go away on its ownThere are no studies that show a kidney infection will go away on its own. HoweverMore importantly, if a kidney infection is left untreated, kidney infectionsit can lead to serious complications and death. Because of this, it is crucial that you seek medical treatment as soon as you start to notice the signs of an infection.

If you are experiencing the signs of a kidney infection, book a visit with a primary care provider to discuss your symptoms.

Mild symptoms of a kidney infection include:

• An urgent need to pee
  
• Frequent urination
  
• Pain or burning while peeing
  
• Cloudy or hazy urine
  
• Foul-smelling urine
  
  

Kidney infections require urgent treatment. Seek immediate medical care from the nearest emergency room if you experience more severe symptoms like:

• Back or side pain
  
• Stomach pain
  
• Fever
  
• Chills
  
• Nausea
  
• Vomiting
  
  

How are kidney infections diagnosed?

Healthcare providers use a test called urinalysis to diagnose kidney infections. Urinalysis measures the level of white blood cells and the acid content of a urine sample. These substances can indicate the presence of an infection.

In addition to a urine test, you may be asked to undergo imaging tests like an X-ray or CT scan. These imaging tests allow healthcare providers to visually examine the kidneys or other internal organs. You may be asked to prepare for these tests. Your provider will give directions as to how you should do so.

How do I treat a kidney infection?

Kidney infections require a course of antibiotics for treatment. Severe kidney infections may require hospitalization.

After a few days of antibiotic treatment, you should start to feel betterYou should start feeling better after a few days of antibiotic treatment. Continue to take your medication even after symptoms begin to go away. Taking the full course of treatment will ensure that The full course of treatment will ensure the infection is completely treated.

How do I prevent kidney infections?

There are several home remedies and self-care steps you can take You can take several home remedies and self-care steps to prevent UTIs and kidney infections. These include:

1. Drink plenty of fluids: Fluids, especially water, can help wash away bacteria from the kidneys and urinary tract through urine flow.

2. Urinate after intercourse: Going pee as soon as possible after sexual intercourse can help cleanse the urethra of bacteria.

3. Empty your bladder: Urinate as soon as you feel the urge to, and make sure you empty your bladder completely. This cleanses the urinary tract of bacteria.

4. Practice good genital hygiene: Keep the genital area clean, but avoid using harsh soaps or douching as scented products can irritate the area. Women should also wipe front to back to decrease the risk of fecal bacteria getting closer to the urethra.
   
   

How Sesame can help

If you’re experiencing the warning signs of a UTI, don’t wait to get treatment. Book an online UTI appointment on Sesame to talk to a provider right away. These convenient video visits connect you with a licensed healthcare provider who can address your symptoms, offer medical advice, and prescribe medication if appropriate.

Sources:

• What is Kidney (Renal) Infection - Pyelonephritis?. Urology Care Foundation.
  
• (2008). If You Choose Not to Start Dialysis Treatment. National Kidney Foundation.
  
• (2017). Definition & Facts of Kidney Infection. National Institute of Diabetes and Digestive and Kidney Diseases.
  
• (2017). Diagnosis of Kidney Infection. National Institute of Diabetes and Digestive and Kidney Diseases.
  
• (2017). Treatment for Kidney Infection. National Institute of Diabetes and Digestive and Kidney Diseases.
  
• Belyayeva M, Leslie SW, Jeong JM. (2024). Acute Pyelonephritis. NIH.gov.
  
• Berg, S. (2023). What doctors wish patients knew about UTI prevention. American Medical Association.
  
• Porat A, Bhutta BS, Kesler S. (2023). Urosepsis. NIH.gov.
  

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