What Is a Urinary Tract Infection?

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A urinary tract infection (UTI) is a common infection that can affect any part of the urinary system, including the kidneys, bladder, and urethra (the tube through which urine exits the body). Sexual activity is a common cause, though not the only one. While as many as 60 percent of women will experience a UTI, men and children can also be affected. A urinalysis is usually used to confirm a UTI and antibiotics are used to treat symptomatic infections. Symptoms may include pelvic pain, an increased urge to urinate and pain with urination, and blood in the urine.

While the majority of UTIs are not serious, some can lead to kidney impairment, pregnancy complications, and a potentially life-threatening complication known as sepsis.

Fortunately, most are treated effectively, and prevention strategies can help fend off future infections.

Urinary Tract Infection Symptoms

Urinary tract infections don't always cause symptoms. When they do, they can affect the lower urinary tract (the urethra and bladder) or the upper urinary tract (the kidneys). Those that involve the kidneys tend to be more severe.

The signs and symptoms of a UTI may include:

  • A persistent urge to urinate (urinary urgency)
  • Burning or pain when urinating (dysuria)
  • Passing frequent, small amounts of urine
  • Cloudy urine (caused by pus in urine, or pyuria)
  • Pink, red, or brownish urine (caused by blood in urine, or hematuria)
  • Strong-smelling urine
  • Pelvic pain in women
  • Fever, nausea, and vomiting (most often due to a kidney infection)
Urinary Tract Infection Symptom
Verywell / Gary Ferster

The most common symptoms in babies are fever and fussiness. Similarly, in the elderly, the symptoms can be often vague and non-specific, such as fatigue or incontinence.

If left untreated, a UTI can lead to rare but serious complications, such as acute or chronic kidney infections (pyelonephritis), the narrowing of the male urethra (stricture), preterm birth, or potentially deadly, the whole-body inflammatory response known as sepsis.


Urinary tract infections typically occur when bacteria enter the urethra and migrate to the bladder and kidneys. While the immune system can usually neutralize these microbes, there are conditions by which they can take hold and multiply into a full-blown infection.

The most common cause of UTIs is the transfer of bacteria from the rectum or vagina to the urethra.

Around 80 percent are caused by E. coli bacteria commonly found in the gut or feces. Others, like Staphylococcus saprophyticus, are naturally found in the vagina and can be transferred to the urethra during sexual intercourse.

Among the most common causes and risk factors:

  • The female anatomy places a woman at greater risk due to the shorter distance from the opening of the urethra to the bladder.
  • Sexually active women are at greater risk than non-sexually active women, with the risk rising in tandem with the frequency of sex.
  • Diaphragms can promote the growth of coliform bacteria like E. coli.
  • Spermicidal lubricants can trigger genital inflammation.
  • An enlarged prostate or kidney stones can obstruct the flow of urine and allow bacteria in the bladder to establish an infection.
  • Uncircumcised men may harbor harmful bacteria under the foreskin.
  • Diabetes can increase urine glucose that bacteria feed on.
  • Menopause can alter the protective flora in the vagina.
  • Catheters can instigate infection due to non-sterile or prolonged use.
  • Douching and feminine deodorants may give bacteria a chance to invade.
  • Potty training can also lead to UTIs, most especially in girls but also in uncircumcised boys.

There are even genetic conditions that may predispose a person to a urinary tract infection.


Those who have had a UTI before commonly say that they know exactly when another one has arrived. However, evaluation by a doctor is necessary before starting treatment to ensure that that hunch is indeed correct.

In addition to reviewing your symptoms, a doctor can use a number of common diagnostic tests or procedures to confirm a UTI:

  • A urinalysis can check for blood, pus, glucose, and other abnormalities in the urine.
  • A urine culture can be used to identify the bacterial strain in urine.
  • Magnetic resonance imaging (MRI) or computed tomography (CT) scans may be used to detect abnormalities in the urinary tract.
  • A cystoscope, a long flexible viewing device, can be inserted into the urethra to get an up-close view of the bladder.

Additional test may be performed to see whether there may be other explanations for the symptoms, including a yeast infection, interstitial cystitis, or a sexually transmitted disease like gonorrhea or chlamydia (especially in young men).


Uncomplicated urinary tract infections are standardly treated with a short course of antibiotic drugs, including:

  • Trimethoprim/sulfamethoxazole (TMP-SMX)
  • Fosfomycin
  • Nitrofurantoin
  • Cephalexin
  • Ceftriaxone

Depending on the choice of drug and the severity and/or recurrence of the infection, the duration of treatment can be as short as three days or last longer than a week. Severe infections, such as those affecting the kidneys, may require a longer course of oral or intravenous antibiotics.

Asymptomatic UTIs (UTIs without symptoms) are usually not treated. The only exception is during pregnancy in which a seven-day course of antibiotics may decrease the risk of preterm birth and low birth weight.

While there are no alternative remedies able to treat a UTI, foods high in vitamin C may help bolster the immune response, while unsweetened cranberry juice may support the normalization of the kidney function.


While urinary tract infections are common, there are things you can do to significantly decrease your risk. They typically involve changes in your personal hygiene and sexual habits.

The primary aim is to avoid the introduction of harmful bacteria into your urinary tract. The secondary aim is to maintain your urinary tract health and make it far less vulnerable to infection.

Some of the more effective means of prevention include:

  • Drinking plenty of water—at least eight glasses per day—to promote urination and kidney health
  • Never holding urine in
  • Cleaning your genitals before and after sex; urinating after sex to help clear the urinary tract
  • Using condoms
  • Avoiding spermicides and diaphragms
  • Wiping from front to back to avoid the transfer of fecal bacteria from the anus to the vagina
  • Cleaning under the foreskin daily, if you are uncircumcised
  • Wearing breathable cotton underwear to reduce moisture build-up


UTIs are often fleeting, but some people may have recurrent infections that can be quite disruptive to their day.

To better cope with UTIs, increase your fluid intake and go to the restroom often to help "flush out" the infection. For pain, consider using a heating pad or mind-body techniques to take your thoughts off of your discomfort. You may also find it helpful to discuss your diagnosis with a close friend. UTIs are very common, and she may not only be able to offer you some advice but give you a much-needed moment of commiseration. 

A Word From Verywell

If you or someone you love is experiencing symptoms of a UTI, make an appointment to see a primary care physician or OB/GYN for treatment. Leaving an infection like this alone, however mild, is never a good idea. On rare occasion, it can lead to a more serious illness that will not only be harder to treat but may cause permanent, irreversible damage.

If you do start antibiotic therapy, never stop halfway through—even if your symptoms clear. Doing so can lead to the development of an antibiotic-resistant bacteria, making it all the more difficult to re-treat a UTI should it recur.

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Article Sources
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  1. Urology Care Foundation. American Urologic Association. Urinary Tract Infections in Adults

  2. American Academy of Pediatrics. healthychildren.org. Recurrent Urinary Tract Infections (UTIs) in Children

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