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Urinary Tract Infections

Urinary tract infections (UTIs) are a common medical complaint. It is estimated that up to 40 percent of women will have a UTI at some time in their lives. Also called bladder infections or cystitis, a UTI occurs when bacteria enter the bladder, usually through the urethra (urine tube), and begin to multiply.

Urine contains fluids, salts and waste products but is sterile or free of bacteria, viruses and other disease-causing organisms. A UTI occurs when bacteria from another source, such as the nearby anus, gets into the urethra. The most common bacteria found to cause UTIs is Escherichia coli (E. coli). Other bacteria can cause UTI, but E. coli is the culprit about 90 percent of the time.

E. coli normally lives harmlessly in the human intestinal tract, but it can cause serious infections if it gets into the urinary tract. In women, the trip from the anus to the urethra is a short one. This is the reason why "wiping front to back" after using the toilet is helpful in preventing UTI.

An untreated UTI can move up to the kidneys and cause an even more serious infection, so prompt diagnosis and treatment is important. Sexually active women, pregnant women and older women all may be at increased risk for UTI.

The symptoms of UTI can include:

  • Pain or burning with urination
  • Lower abdominal pain or pressure
  • The need to urinate frequently
  • The urine may look cloudy or darker in color or it may appear bloody

A fever, flank pain, nausea or vomiting accompanying any of these symptoms could signal that the infection has reached the kidneys, and you should seek immediate medical attention.

However, some women, especially older women, may have very subtle or no symptoms. If you experience a sudden increase in the need to urinate often, or start to leak urine involuntarily, UTI could be the cause — especially if this is a new problem.

If you have UTI symptoms, notify your health care provider. You may be advised to come into the office for a urine test, especially if this is the first time you've had these symptoms, or if you've had a number of infections in the past year. A urine sample given at the office can be tested rapidly for the presence of pus (white blood cells), bacterial residue (nitrites) and traces of blood. If the test is positive, your health care provider will discuss the appropriate treatment.

The urine also may be sent for culture and sensitivities. A culture can identify the kind of bacteria growing in the bladder and urine and can help determine which antibiotics are most effective. Because this test can take one or two days, you will begin treatment right away with an antibiotic commonly used to treat UTI.

For an uncomplicated UTI, a three- to seven-day course of antibiotics will provide rapid relief. You may also receive a prescription for pyridium, a medication that eases bladder pain while the antibiotic is taking effect. For recurrent or more serious infections, treatment may be extended to 10 to 14 days.

Patients with four or more infections a year may need to take small doses of antibiotics daily or with intercourse for several months to allow the bladder to heal. Vaginal estrogen cream also may prevent recurrent UTIs in postmenopausal women.

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Reviewed by health care specialists at UCSF Medical Center.