What are urinary tract infections?
First, there’s the seemingly constant feeling of having to go to the bathroom and then there’s the burning feeling when you do urinate. Those who have had one—or more—recognize these as classic symptoms of a urinary tract infection (UTI), the most common infection in the United States.
Though the symptoms are unpleasant and sometimes embarrassing, UTIs are usually resolved quickly with a course of antibiotics. Still, they lead to millions of medical office visits and billions of dollars spent in diagnosis and treatment. And for some people, UTIs keep coming back (recurring) with frustrating frequency.
A UTI occurs in part of the urinary system, which includes the urethra, bladder, ureters, and kidneys. Nearly all UTIs are bacterial, most frequently caused by Escherichia coli, which normally plays a vital role in keeping the digestive system healthy, but can cause infection if it enters the urinary tract. Smaller numbers of UTIs may be caused by yeast, a type of fungus.
Bladder infections (lower UTIs), which lead to more than 10.5 million medical office visits each year in the United States, are also known as acute cystitis. Bladder infections are more common than kidney infections (upper UTIs), but kidney infections tend to be more severe and more likely to lead to hospitalization. Each year, about 250,000 Americans are diagnosed with kidney infection, also called pyelonephritis.