General Description
Urinary tract infections (UTIs), which include infections of the
kidneys, bladder, and urethra, are among the most common types of
infection, accounting for about 9.6 million doctor visits per year
in the United States.1 UTIs occur when microorganisms
(usually bacteria from the digestive tract) cling to the opening
of the urethra and begin to multiply. Most UTIs are caused by E.
coli, a type of bacteria that normally live in the colon. Infection
limited to the urethra, where most UTIs begin, is known as urethritis.
From there, bacteria often move on to the bladder, causing bladder
infection (cystitis). If the infection is not promptly treated,
bacteria may move up the ureters to infect the kidneys (pyelonephritis).
UTIs occur more often in women than in men; one out five women will
develop a UTI during her lifetime. Many women suffer from recurrent
UTIs. Although UTIs in men are less common, they can be very serious
when they occur.
Although not everyone with a UTI has symptoms, in most cases
there are signs such as pain or pressure above the pubic bone,
a frequent urge to urinate, and a painful, burning feeling in
the area of the bladder or urethra during urination. The urine
itself may look milky or cloudy, even reddish if blood is present.
If the infection reaches the kidneys, there may be other symptoms
such as fever, back pain, nausea, or vomiting. Symptoms of UTIs
in children are often overlooked or attributed to another disorder.
In children, UTIs may cause irritability, loss of appetite, incontinence,
or persistent fever. To determine whether a UTI is present, doctors
test a urine sample for pus and bacteria.
Contributing factors
The urinary system is structured in a way that helps ward off
infection. The ureters and bladder normally prevent urine from
backing up into the kidneys, and the flow of urine from the bladder
helps wash bacteria out of the body. The immune system also helps
protect against UTIs. Any disorder that interferes with the immune
system (e.g., diabetes, AIDS) or obstructs the flow of urine (e.g.,
kidney stones) raises the risk for UTI. There is also an increased
risk for UTI in people who have catheters, or tubes, placed in
the bladder. Certain forms of birth control, including diaphragms
and spermicidal foam, are also associated with increased risk
for UTIs.1
Research funded by the National Institutes of Health (NIH) suggests
that one factor behind recurrent UTIs may be the ability of bacteria
to attach to cells lining the urinary tract. A recent study has
shown that women with recurrent UTIs tend to have certain blood
types. Some scientists speculate that women with these blood types
are more prone to UTIs because the cells lining the vagina and
urethra may allow bacteria to attach more easily.1
Further research may show if this association is sound and proves
useful in identifying women at high risk for UTIs.
Conventional treatment
UTIs are normally treated with antibiotics. In what is known as
a sensitivity test, bacteria from urine samples are grown in a
culture and tested against different antibiotics to determine
which drug best destroys the bacteria. The choice of drug and
length of treatment period depend on the patient's history and
the results of the sensitivity test. Often, a UTI can be cured
in 1 or 2 days of treatment if the infection is not complicated
by an obstruction or nervous system disorder. However, many doctors
ask their patients to take antibiotics for a week or two in order
to ensure that the infection has been cured. In addition, UTIs
caused by certain types of bacteria, such as Mycoplasma and Chlamydia,
can take longer to clear than others. Kidney infections generally
require several weeks of antibiotic treatment.
Nutritional/lifestyle considerations
There are several dietary and behavioral measures women can take
to decrease their risk of UTIs. A balanced diet rich in antioxidants
helps keep the immune system strong, to fight off harmful bacteria.
Drinking plenty of fluids helps maintain regular urine flow to
flush bacteria out of the urinary tract. Wiping from front to
back helps to prevent bacteria from the anus from entering the
vagina or urethra. Other hygienic practices such as cleansing
the genital area after intercourse and taking showers instead
of baths can also help prevent infection. Scented douches and
feminine hygiene sprays can irritate the urethra and should be
avoided.1
With the growing concern about the overuse of antibiotics, interest
in alternative treatments for UTIs has increased. Several herbs,
including cranberry, bearberry leaf, garlic, buchu leaf, parsley,
Java tea, goldenseal, and nettle have traditionally been used
to fight UTIs, but most of these lack scientific evidence supporting
their use. Some of these, like nettle, buchu leaf, and parsely,
have diuretic effects while others such as garlic, bearberry,
and goldenseal have antibacterial activity. Several studies have
shown that cranberry juice helps protect against UTIs, apparently
by inhibiting the ability of bacteria to adhere to the walls of
the urinary tract.4-8 Germany's Commission
E has approved bearberry leaf and Java tea for the treatment of
UTIs,9 and these herbs are used widely throughout
Europe for urinary ailments. |
