Carl R. Darnall Army Medical Center - Health Library

Conditions InDepth: Urinary Tract Infection (UTI)

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

The urinary system is made up of:

  • Two kidneys—filter wastes 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 you’re 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

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A UTI happens when bacteria on the skin, genitals, or rectal area get into the urethra. Once there, they grow and spread. A UTI can also be caused by:

  • A medical procedure or surgery.
  • Placing a catheter—A tube placed through the urethra and into the bladder. Bacteria climb the tube into the bladder.
  • Having sex.

Many types of bacteria can cause a UTI. Rarely, they can be caused by fungi. In children, they can be caused by viruses.

REFERENCES:

Bacterial urinary tract infections (UTIs). Merck Manual Professional Version website. Available at: https://www.merckmanuals.com/professional/genitourinary-disorders/urinary-tract-infections-utis/bacterial-urinary-tract-infections-utis. Updated June 2018. Accessed September 20, 2018.

Definition & facts. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/urologic-diseases/bladder-infection-uti-in-adults/definition-facts. Updated March 2017. Accessed September 20, 2018.

Uncomplicated urinary tract infection (UTI) (pyelonephritis and cystitis). EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T116894/Uncomplicated-urinary-tract-infection-UTI-pyelonephritis-and-cystitis. Updated June 4, 2018. Accessed September 20, 2018.

Urinary tract infections in adults. Urology Care Foundation website. Available at: https://www.urologyhealth.org/urologic-conditions/urinary-tract-infections-in-adults. Accessed September 20, 2018.

Last reviewed September 2018 by EBSCO Medical Review Board Adrienne Carmack, MD  Last Updated: 9/20/2018