Health Information and Self Care Advice for Scotland

Urinary tract infection

Definition

Urinary tract infection (UTI) is the name given to an infection of any part of the urinary system.

The urinary system is made up of the kidneys, the ureters (the tubes that carry urine from the kidneys to the bladder), the bladder and the urethra. The kidneys remove waste products from the blood to make urine, which then travels through the ureters to the bladder, where it is stored until it leaves the body through the urethra.

The kidneys and the ureters are known as the upper urinary tract. An infection of this part of the urinary system is called pyelonephritis.

The bladder and the urethra are known as the lower urinary tract. An infection of the bladder is called cystitis, while an infection of the urethra is called urethritis.

Urinary tract infection develops when part of the urinary system becomes infected, usually by bacteria. Bacteria can enter the urinary system through the urethra, or, more rarely, though the bloodstream. Bacteria commonly enter the urethra during sexual intercourse or due to poor hygiene.

The symptoms of lower urinary tract infection can include:

• pain or a burning sensation during urination (dysuria),
• needing to urinate frequently or urgently,
• feeling that you are unable to urinate fully,
• cloudy, bloody or bad-smelling urine,
• pain in your lower abdomen, and
• mild fever (a high temperature between 37-38.3°C or 98.6-101.0°F).

The symptoms of upper urinary tract infection can include:

• any of the symptoms of a lower urinary tract infection,
• a high fever (a high temperature over 38.3°C or 101.0°F),
• nausea or vomiting,
• shaking or chills, and
• pain in your back or side, usually on only one side.

Women are more likely to develop UTI than men. This is because in a woman the urethra is situated closer to the anus than in a man, making it easier for bacteria from the anus to reach the urethra. The female urethra is also much shorter than the male urethra (which runs through the penis), so it is easier for bacteria to reach the bladder.

You are more likely to develop a UTI if:

• you have a condition that obstructs or blocks the urinary tract, such as kidney stones,
• you have a condition that prevents you from emptying your bladder fully,
• you have a weakened immune system, for example because you have diabetes or you are undergoing chemotherapy,
• you are female and sexually active, as sexual intercourse can irritate the urethra, allowing bacteria to more easily travel through the urethra into the bladder,
• you use a diaphragm for birth control,
• you are male and have an enlarged prostate gland, or
• you have a urinary catheter.

A urine test may help with the diagnosis of UTIs in children and adult males but is not always necessary for women. Most UTIs can be treated with antibiotics.

There are things you can do to reduce your risk of getting a UTI:

• Drink plenty of liquids, especially water. This should help wash bacteria from the bladder and urinary tract.
• Go to the toilet as soon as you feel the need to urinate, rather than holding it in.
• Wipe from front to back after going to the toilet.
• Practice good hygiene wash your genitals every day and before having sex.
• Empty your bladder after sex.

For more detailed information on urinary tract infections, see our health encyclopaedia articles on:

• Cystitis
• Pyelonephritis

Last updated on 29 April 2009 10:48 AM