by Carmack A

The urinary tract is a system of organs. Wastes are filtered from the blood to make urine (pee). It moves through the tract until it passes from the body.

The system is made up of:

  • Two kidneys—filter waste from blood and make urine
  • Two ureters—tubes that move urine from the kidneys to the bladder
  • Bladder—a hollow organ that holds urine until a person is ready to pass it
  • Urethra—a tube that passes urine out of the body from the bladder

A UTI can happen in any of these structures.

The Urinary Tract
Copyright © 2002 Nucleus Communications, Inc. All rights reserved.

This health problem happens when bacteria on the skin, genitals, or rectum get into the urethra. The bacteria can also get to the kidneys and the rest of the system by travelling through the blood. Once there, the bacteria grow and spread. A UTI can also be caused by:

  • A procedure or surgery
  • A catheter (tube) placed through the urethra and into the bladder
  • Sex

Many types of bacteria can cause this health problem. Rarely, they can be caused by fungi. In children, they can be caused by viruses.

What are the risk factors for a urinary tract infection?What are the symptoms of a urinary tract infection?How is a urinary tract infection diagnosed?What are the treatments for a urinary tract infection?Are there screening tests for a urinary tract infection?How can I reduce my risk of getting a urinary tract infection?What questions should I ask my doctor?Where can I get more information about urinary tract infections?


Bladder infection (urinary tract infection)—UTI) in adults. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: Accessed March 30, 2022.

Introduction to urinary tract infections (UTIs). Merck Manual Professional Version website. Available at: Accessed March 30, 2022.

Uncomplicated urinary tract infection (UTI) (pyelonephritis and cystitis). EBSCO DynaMed Plus website. Available at: Accessed March 30, 2022.

Urinary tract infections in adults. Urology Care Foundation website. Available at: Accessed March 30, 2022.

Revision Information