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What is a urinary tract infection? | Understanding UTIs, Part 1

This is the first part in Understanding UTIs, an accessible series about urinary tract infections, including their symptoms, causes, medications and more.

Karen, a 50-year-old married nurse with two grown sons, was enjoying her weekly Sunday bike ride when she suddenly felt the urgent need to pee. Over the next two hours, she stopped four times to use the restroom, but she could not get rid of the persistent sensation in her bladder. Each time she produced only a small amount of urine. She quickly recognized a familiar picture and decided to come into the clinic.

Sound familiar?

Urinary tract infections (UTIs) are responsible for more than 8 million visits to health care providers in the United States each year, and 60% of women have at least one UTI in their lifetime. UTIs are very common, but what exactly is a UTI? What are the different types of UTIs? And what symptoms should you be looking out for?

What is a UTI?

A UTI occurs when bacteria infect any part of the urinary tract, which includes the kidneys, ureters, bladder and urethra. Urine produced in each kidney travels down a small tube called a ureter to the bladder where it is stored. Then, urine passes through the urethra to exit the body. UTIs most often affect the bladder.

Are there different types of UTIs?

At the clinic, Karen explained: "I know I have a UTI, bladder infection or kidney infection."

But, as Karen's health care provider explained, those are all types of UTIs. The different names just specify how far up the urinary tract the infection has traveled.

An uncomplicated UTI is an infection in the lower urinary tract, the bladder and urethra. A complicated UTI is when the infection extends beyond the bladder to the kidneys and is more serious. UTIs are also considered complicated during pregnancy, after menopause, and when there are other issues, such as kidney stones.

What are the symptoms of a UTI?

Karen told her primary care physician: "My symptoms are frequently peeing (six to eight times in a workday), the constant need to pee and very little pee coming out. It really slows down my workday at the hospital." These are the most common symptoms of an uncomplicated UTI.

Symptoms of an uncomplicated UTI
  • Painful or difficult urination (dysuria)
  • Urinating many times in a day (urinary frequency)
  • Sudden urge to urinate (urinary urgency)
  • Pain in the lowest part of the abdomen
  • Pink and/or cloudy urine
Additional symptoms found in a complicated UTI
  • Fever
  • Chills
  • Shivering (rigors)
  • Nausea and/or vomiting
  • Marked fatigue or malaise
  • Discomfort in the upper abdomen or back
  • Pain when lightly pounding over the kidneys below the back ribs

Specific combinations of these symptoms are more commonly found with UTIs than other conditions. For example, if someone has painful urination and is urinating many times in a day, but has no vaginal discharge, this raises the chances of the condition being a UTI to more than 90%.

What else could it be?

If the symptoms don't match a UTI, then another condition could be the cause.

"A yeast infection, sexually transmitted infection, or painful bladder syndrome are sometimes mistaken for a UTI," said Stanford primary care physician Kim Chiang, MD. "It's particularly important that you visit your health care provider so they can make an accurate diagnosis to ensure the most appropriate treatment."

Non-UTI symptoms
  • Discharge
  • Itching (vaginal pruritus)
  • Burning at the end of urination

And Karen?

Karen was diagnosed with an uncomplicated UTI and given antibiotic treatment. She felt better within three days; She got back on track at work and was back on her bike for her next Sunday ride.

If you believe you may have a UTI, please contact a health care professional.

This is the first post in the series Understanding UTIs. The goal of this seven-part series is to provide easy-to-understand, scientifically grounded information about UTIs. Patients referenced are composites, compiled from actual patient experiences.

Joanna Langner is a graduate student in Community Health and Prevention Research at Stanford who is interested in health disparities and women's health. She wrote this series with the support of Randall Stafford, MD, PhD, professor of medicine and director of the Program on Prevention Outcomes and Practices, and Kim Chiang, MD, clinical assistant professor of medicine.

Photo by OneSideProFoto

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