Urinary Tract Infections (UTI)
See also:
Bladder Infection
What
is it?
The term urinary tract infection (UTI) is
used to describe an infection that begins in the urinary system. UTIs
can be painful and annoying. They can also become a serious health
problem if the infection spreads to the kidneys.
Urinary tract infection (UTI) refers to a group of inflammations of
the urethra, bladder, or kidneys. The urinary tract consists of the
kidneys, ureters, bladder, and urethra. The kidneys filter waste
materials from the blood, and these waste materials become urine. The
ureters carry the urine from the kidneys to the bladder, where it is
held until you go to the bathroom. The tube that carries the urine from
the bladder and outside of your body is called the urethra. Urine is
usually sterile, which means it doesn’t contain any bacteria or
infectious organisms. However, these types of organisms sometimes get
into the urinary tract and cause an infection.
Who
gets it?
Urinary tract infections are more common in women than in men. In
fact, 1 in 5 women will develop one during her lifetime, and many will
have more than one. The male urethra is long, so it is harder for
bacteria to get to the bladder. Men are more likely to get a UTI once
past the age of 50. People with kidney stones, urinary tract
abnormalities, weakened immune systems, spinal cord injuries, and
diabetes are more likely to get UTIs, as are patients who have been
catheterized to drain urine directly from the bladder.
What
causes it?
Urinary tract infections can be caused by bacteria, viruses, fungi,
or some types of parasites. The most common types of urinary tract
infections are bladder infections, called cystitis; kidney infections,
called pyelonephritis; and infections of the urethra, called urethritis.
They are caused by bacteria that are normally present in your digestive
system and on the skin around the rectum and vagina. This bacteria can
pass through the urethra and up into the bladder. Urinary tract
infections are not contagious. However, bacteria in the area of the
vagina can get pushed into the urethra during sexual intercourse.
Infections can also be caused by irritation to your genital area, such
as using a diaphragm or spermicides as contraception, wearing tight
pants, and using perfumed soaps. Children, especially girls, are more
likely to get UTIs from bubble baths and other irritants. Men are more
likely to get UTIs when an enlarged prostate gland presses on the
bladder and prevents it from emptying completely, or because of kidney
stones.
Cystitis commonly occurs in women as a
result of sexual intercourse. But even sexually inactive girls and women
are susceptible to lower urinary tract infections because the anus, a
constant source of bacteria, is so close to the female urethra. More
than 90 percent of cystitis cases are caused by Escherichia coli (E.
coli) , a species of bacteria commonly found in the rectal area.
Risk Factors
Some people appear to be more likely than
others to develop UTIs. Women are one such group. Up to 20 percent will
develop a bladder infection over a lifetime. A key reason is their
anatomy. Women have a shorter urethra than men have, which cuts down on
the distance bacteria must travel to reach the bladder.
Women who are sexually active tend to have
more UTIs because sexual intercourse can result in bacteria being pushed
into the urethra. Studies have also shown that women who use diaphragms
for birth control may be at higher risk. After menopause UTIs may become
more common because tissues of the vagina, urethra and the base of the
bladder become thinner and more fragile due to loss of estrogen.
Other risk factors include anything that
impedes the flow of urine, such as an enlarged prostate or a kidney
stone . Changes in the immune system, which can occur with conditions
like diabetes , also can increase the risk of UTIs. So can the prolonged
use of bladder catheters, which may be needed by the chronically ill or
older adults.
New research funded by the National
Institutes of Health suggests that a woman's blood type may play a role
in her risk of recurrent UTIs. Bacteria may be able to attach to cells
in the urinary tract more easily in those with certain blood factors.
But more research is needed to determine whether an association exists
and whether it could be useful in identifying people at risk of
recurrent UTIs.
What
are the symptoms?
Not everyone with a UTI will develop
symptoms, but most people have some. They can include:
- A strong persistent urge to urinate
- A burning sensation when urinating
- Passing frequent, small amounts of urine
- Pain in the lower part of your abdomen or lower back
- Blood in the urine (hematuria) or cloudy, strong-smelling urine
A man with a urinary tract infection may have a
discharge from his penis. A kidney infection is
more serious. Its symptoms include a burning
sensation when you urinate, abdominal and lower
back pain, fever, chills, nausea, the frequent
need to urinate, and cloudy or bloody urine. Some
sexually transmitted diseases can cause symptoms
that look like a UTI. For example, the chlamydia
organism can cause urethritis. For this reason, it
is important to see a doctor for diagnosis if you
have any symptoms of a urinary tract infection.
Symptoms will also get worse if not treated.
Untreated UTIs can spread to the blood and cause a
serious infection that can be fatal.
There are more specific signs and symptoms
for each type of UTI. In addition to the symptoms listed above you may
experience the following:
- Acute pyelonephritis may cause flank pain, high fever, shaking
chills and nausea or vomiting.
- Cystitis may result in pressure in the lower abdomen and
strong-smelling urine.
- Urethritis may lead to pus in the urine. In men, urethritis may
cause penile discharge.
How
is it diagnosed?
If you have any symptoms of a urinary
infection, contact your physician as soon as possible. To diagnose
a UTI, your doctor will look at your medical history, ask about your
symptoms, and perform a physical exam that includes pressing on your
abdomen to check for tenderness. If a UTI is
suspected, your physician will most likely ask for a urine sample to
determine if bacteria are present in your urine. You will wash your
genital area with a disposable wipe, then urinate into a sterile cup.
Your doctor will ask you to begin urinating in the toilet, then stop and
continue urinating into the cup. This is so any bacteria outside the
vagina or on the end of the penis is washed away and not included in the
sample. This sample will be tested for bacteria and other causes of UTIs.
Although no simple test can differentiate between an upper and lower
urinary tract infection, the presence of fever and flank pain may
indicate that the infection involves the kidneys. If you have
repeated infections, your doctor may order additional tests such as an
ultrasound study of your abdomen; intravenous pyelography (IVP), which
is an x-ray of the urinary tract; or a cystoscopy, which involves
inserting a tube into the urethra for a close view of the urethra and
bladder. If you are a man, your doctor will also perform a prostate exam
to check for any tenderness or enlargement. He or she will also check
for and take a sample of any discharge from the penis.
When treated promptly and properly, UTIs
rarely lead to complications. But if they are left untreated, a lower
urinary tract infection can become something more serious than a set of
uncomfortable symptoms.
Untreated UTIs can lead to potentially
life-threatening complications, such as acute or chronic pyelonephritis,
which could permanently damage your kidneys. Young children and older
adults are at the greatest risk of kidney damage due to UTIs because
their symptoms are often overlooked or mistaken for other conditions.
Women who have UTIs while pregnant may also have an increased risk of
delivering low birth weight or premature infants.
What
is the treatment?
Urinary tract infections are usually easy to treat, but it’s
important to begin treatment right away. If you have a mild bladder
infection, drinking plenty of fluids may be enough to wash away the
bacteria and let your body do the rest. In most cases, your doctor will
prescribe antibiotics to fight the infection. If you have a lot of pain
in the abdominal area, your doctor may give you a different medication
for that. Medications for UTIs usually make your urine bright orange.
Follow your doctor’s instructions and take all medications until they
are gone. If you do not, all the bacteria may not be killed and you may
get the infection again. Make sure you drink plenty of fluids everyday.
Research has shown that cranberry juice is also effective in treating
urinary tract infections and even in preventing them. If you are
sexually active, you should avoid sexual intercourse until your symptoms
have been gone for at least two weeks.
Usually, UTI symptoms clear up within a few
days of treatment. But you'll likely need to stay on antibiotics for a
week or more. Indeed, it's important to take the entire course of
antibiotics recommended by your doctor to ensure that the infection is
completely eradicated. For an uncomplicated UTI that occurs when you're
otherwise healthy, your doctor may recommend a shorter treatment with a
double-strength version of a prescription drug. But this will depend on
your particular symptoms and history.
If you have recurrent UTIs, your doctor may
recommend longer antibiotic treatment or refer you to a urologist or
nephrologist for an evaluation to see if urologic abnormalities may be
causing the infections. If abnormalities of the urinary tract are not to
blame, taking a single dose of antibiotic each time after sexual
intercourse may be helpful.
For severe UTIs hospitalization and
treatment with intravenous antibiotics may be required. When recurrences
are frequent or a kidney infection becomes chronic, it's important to
have a urologic evaluation because an underlying physical problem may
require treatment.
Self-care
tips
You can prevent urinary tract infections by making sure you always
empty your bladder completely when you go to the bathroom. Women, in particular, may benefit from the
following:
- Drink plenty of liquids, especially water. Cranberry juice may have
infection-fighting properties.
- Urinate frequently, and avoid retaining your urine for a long time
after you feel the urge to void.
- Wipe from front to back after a bowel movement to prevent bacteria
in the anal region from spreading to the vagina and urethra.
- Take showers rather than bubble baths.
- Wash the skin around the vagina and anus daily.
- Empty your bladder as soon as possible after intercourse, and drink
a full glass of water to help flush bacteria.
- Avoid using deodorant sprays or feminine products such as douches
in the genital area that could irritate the urethra.
- Wear cotton underwear
- If you are sexually active, make sure you wash your genital area
and urinate after intercourse. This will help to remove any bacteria
that could travel up the urethra.
Men can prevent UTIs by wearing condoms during
intercourse. If you are uncircumcised, make sure
you wash carefully under your foreskin each time
you bathe.
UTIs can be painful, but you can take steps
to ease your discomfort until antibiotics clear the infection. Sometimes
a heating pad placed over the abdomen can help minimize feelings of
stomach pressure or pain. It's also a good idea to avoid coffee,
alcohol, soft drinks with caffeine, citrus juices and spicy foods until
you have finished a course of antibiotics. These items can irritate the
bladder and aggravate the frequent or urgent need to urinate.
If recurrent bladder infections are a
problem, make sure your physician is aware of this. Together, you can
develop a strategy to reduce recurrences and the discomfort they can
bring into your life. Call your doctor if symptoms return after
treatment, or do not get better after a few days of treatment.
References from Medline
Plus
Physicians who treat this condition
This information has been designed as a comprehensive and quick reference
guide written by our health care reviewers. The health information written
by our authors is intended to be a supplement to the care provided by your
physician. It is not intended nor implied to be a substitute for
professional medical advice.
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