Definition

A urinary tract infection (UTI) is an infection in any part of the urinary system. Most UTIs start in the lower urinary tract in the bladder or urethra. The urethra is the tube that carries urine out of the body. A UTI can also include an infection in the upper urinary system, including the kidneys.

There are different names for infections in different parts of the urinary system, including:

• Uretheral infection—urethritis
• Bladder infection—cystitis
• Kidney infection—pyelonephritis

The infection may also occur in the tube connecting the bladder to the kidney (ureter). All of these infections are considered to be UTIs.

Causes

UTIs are caused by bacteria that most often come from the digestive tract or rectal area. The bacteria cling to the opening of the urethra and begin to multiply. If the infection is not treated right away, bacteria may move up the urinary system to the kidneys.

Most infections are caused by a bacteria that normally lives in the colon. The bacteria may move from the rectal area to the urethra.

UTIs can also be sexually transmitted. This type of infection usually does not spread past the urethra. Both partners need to be treated.

Risk Factors

UTIs are more common in women because the rectum and urethra are close to each other, making infection more likely.

Other factors that may increase your chance of a UTI include:

• Being sexually active
• Using a diaphragm for birth control
• Menopause
• Diabetes
• Kidney stones
• Enlarged prostate
• Weak immune system
• Abnormalities of the urinary system, such as vesicoureteral reflux or polycystic kidneys
• Paraplegia or quadriplegia
• Sickle-cell anemia
• History of kidney transplant
• Bladder catheter in place, or recent device inserted into the urinary system
• Pregnancy

Symptoms

UTIs may cause:

• Frequent and urgent need to urinate
• Passing small amounts of urine
• Pain in the abdomen or pelvic area
• Burning sensation during urination
• Cloudy, bad-smelling urine
• Increased need to get up at night to urinate
• Leaking urine
• Fever and chills
• Nausea and poor appetite

An infection in the kidney can be more serious. Call your doctor right away if you have symptoms of a kidney infection, such as:

• Bloody urine
• Low back pain or pain along the side of the ribs
• High fever and chills

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will also be done. A sample of your urine will be tested for blood, pus, and bacteria.

In general, children and men are less likely to get UTIs. Their infections are more likely to be caused by structural problems of the kidneys, bladder, or tubes. As a result, children and men may need more testing to determine the cause of a UTI.

Treatment

UTIs are treated with antibiotics. Standard medical care for a UTI includes taking antibiotics for 3 days. You will probably start to feel better after 1-2 days. It is important that you continue to take the entire course of medication, even if you feel better.

You may have your urine checked after you finish taking the antibiotics. This is to make sure that the infection is truly gone. If you have recurrent infections, you may be referred to a specialist.

The infection may cause pain and spasms in the bladder. Your doctor may recommend a medication called phenazopyridine. It may turn your urine, and sometimes your sweat, an orange color.

Severe UTIs may need a strong initial dose of antibiotics. You may be given antibiotics through an IV or an injection.

Prevention

To help keep bacteria out of your urinary tract:

• Drink plenty of fluids throughout the day. Cranberry juice is a good choice.
• Urinate when you feel the need and do not resist the urge.
• Empty your bladder completely and drink a full glass of water after having sex.
• Wash genitals daily.
• If you are a woman, always wipe from the front to the back after having a bowel movement.
• Avoid using douches and feminine hygiene sprays.

National Kidney and Urologic Diseases Information Clearinghouse http://kidney.niddk.nih.gov

Women’s Health Matters http://www.womenshealthmatters.ca

Jepson RG, Craig JC. Cranberries for preventing urinary tract infections. Cochrane Database Syst Rev. 2008;(1):CD001321.

Uncomplicated urinary tract infection (UTI) (pyelonephritis and cystitis). EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed
Updated June 24, 2015. Accessed September 1, 2015.

Urinary tract infections in adults. Urology Care Foundation website. Available at:
http://www.urologyhealth.org/urology/index.cfm?article=47
Accessed September 1, 2015.

Urinary tract infections in adults. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at:
http://kidney.niddk.nih.gov/kudiseases/pubs/utiadult
Updated May 24, 2012. Accessed September 1, 2015.

Urinary tract infection (UTI) in men. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed
Updated June 27, 2014. Accessed September 30, 2014.

12/5/2007 DynaMed’s Systematic Literature Surveillance
http://www.ebscohost.com/dynamed:
Pohl A. Modes of administration of antibiotics for symptomatic severe urinary tract infections. Cochrane Database of Syst Rev. 2007;(4):CD003237.

5/6/2011 DynaMed’s Systematic Literature Surveillance
http://www.ebscohost.com/dynamed:
Barbosa-Cesnik C, Brown MB, Buxton M, Zhang L, DeBusscher J, Foxman B. Cranberry juice fails to prevent recurrent urinary tract infection: results from a randomized placebo-controlled trial. Clin Infect Dis. 2011;52(1):23-30.