Kidney infections are a type of urinary tract infection (UTI) and are common, especially among those with kidney disease, diabetes, and weakened immune systems. Since kidney infections can vary in severity, it is important to learn all the expected symptoms, when to seek medical attention, and treatment options.* 

How Does a Kidney Infection Occur?

Also known as pyelonephritis, kidney infections are believed to start at the lower parts of the urinary tract, such as the bladder or urethra. It often occurs when bacteria from bowel movements enter the urinary tract. As it moves up the urinary tract, it progresses to the bladder and then the kidneys. 

What Are the Symptoms of a Kidney Infection?

A kidney infection symptoms will usually arise over several hours and may include:

• Pain in the back, side, or abdomen
• Urine changes, such as urine being cloudy, smelling bad, or containing blood
• Fever
• Chills
• Nausea and/or vomiting

When Should I Seek Medical Attention?

Kidney infections can vary in severity but should always be taken seriously. According to a 2019 study, kidney infections lead to 250,000 office visits and 200,000 hospital admissions in the United States. 

Schedule a doctor’s appointment if you are experiencing less severe symptoms such as:

• Urgent, painful urination
• Cloudy, foul-smelling, or bloody urine
• Abdominal pain
• Pelvic or bladder pressure

Seek an urgent care center or hospital when your symptoms indicate a severe infection, including: 

• Severe back or side pain
• Fever
• Chills
• Nausea or vomiting

What Happens to Untreated Kidney Infections?

Do not hesitate to seek care when you feel something is not right. Untreated kidney infections can lead to serious complications, such as:

• Kidney damage and potentially chronic kidney disease (CKD)
• High blood pressure
• Kidney failure
• Kidney abscess
• Sepsis (infection of the blood)

What Are the Treatment Options for a Kidney Infection?

Treatment for a kidney infection may include:

• Antibiotics, oral or intravenous (IV), if hospitalized, can either kill bacteria or slow the growth.
• Over-the-counter (OTC) pain medications to reduce pain and fever
• Fluids are important to flush bacteria out of your urinary tract. In hospitalized individuals, fluids will be administered through an IV. 
• Rest is also important to help your body fight off an infection. 

While kidney infections are serious conditions, timely treatment significantly reduces the risk of complications and further illness. 

*Seladi-Schulman, J. (2021, April 12). Signs of a Kidney Infection: When Should You Go to the Hospital? Healthline. https://www.healthline.com/health/kidney-health/kidney-infection-when-to-go-to-hospital#outlook