What is a UTI?

Diagram of the urinary tract
The urinary tract is made up of the kidneys, urethra and bladder.

A urinary tract infection, or UTI, is an infection caused by bacteria in any or all parts of the urinary tract. The kidneys, bladder and urethra make up the urinary tract. The bacteria can come from 2 places, which are the skin around the rectum (bottom) and genitals and the bloodstream from other parts of the body.

UTIs are common in infants and children, but girls are more likely than boys to get UTIs. Girls have a shorter urethra (the small opening that connects to the bladder so urine can flow out) than boys. This makes it easier for bacteria to enter the urinary tract. Infant boys who are uncircumcised also have a higher risk of getting UTIs because of bacteria that settle under the foreskin.

There are 3 types of UTIs, which are:

  • Urethritis, caused by bacteria in the urethra
  • Cystitis, caused by bacteria in the bladder
  • Pyleonephritis, caused by bacteria that spread to the kidneys. This is a very serious infection that can cause kidney scarring and affect the way the kidneys work.

What Are the Symptoms of a UTI?

The symptoms of a UTI can be uncomfortable for your child. Symptoms include:

  • Having to urinate more often
  • Pain or burning while urinating
  • Not wanting to urinate because it is painful
  • Fever
  • Daytime or nighttime wetting
  • Foul-smelling urine
  • Belly (abdominal) pain
  • Decreased appetite
  • Irritability in infants

Did You Know...?

The bacteria that cause a UTI often come from the intestines (the gut). When children have a bowel movement, these bacteria can stay on their skin if they do not wipe properly.

Rev. 5/2015. Mass General for Children and Massachusetts General Hospital do not endorse any of the brands listed on this handout. This handout is intended to provide health information so that you can be better informed. It is not a substitute for medical advice and should not be used to treatment of any medical conditions.