Urinary-tract infections are the most common of all bacterial infections in the United States, accounting for more than 8 million health-care visits a year, according to the Centers for Disease Control and Prevention. As many as 80 percent of women will get at least one UTI, and 20 to 30 percent of those who have had one will suffer recurrent bouts.

The infection can be caused by sexual activity that transmits microbes into a woman’s urinary tract. Other causes include certain spermicides that irritate the skin’s bacterial defenses, and diaphragms that slow the urinary flow that helps rid the urethra of microbes. For both men and women, conditions such as diabetes, which weakens the body’s natural immune defenses, and the use of urinary catheters boost the risk of infection because bacteria can travel through or around the tubes into the bladder.

After age 50, men tend to get UTIs at rates similar to those of women. That’s probably because in middle age a man’s prostate, which sits near the base of the bladder, can become enlarged, slowing urine flow. Bacteria can stick to the wall of the urethra or bladder and multiply, increasing the likelihood that bacteria will form colonies and trigger an infection.

Research indicates that Escherichia coli (E. coli) — bacteria that are normally found in the bowel and that cause most UTIs — and other microbes are becoming increasingly resistant to the reliably active antibiotics available to fight them. The emergence of drug-resistant bacteria is a serious health concern, sometimes causing doctors to try several antibiotics.

Here are some steps you can take to avoid, identify and treat UTIs.

To help flush bacteria from the lower urinary tract, drink plenty of water: six to eight eight-ounce glasses a day. (Bigstock)
Symptoms and diagnosis

Symptoms might include a strong urge to urinate often (though you might pass only small amounts of urine), pain or burning during urination, and cloudy or bloody urine that might have a foul odor. Older women and men are more likely to have symptoms that are vague, such as feeling tired and weak, sometimes with muscle aches and abdominal pain.

Instead of talking about their symptoms with a doctor, some people use at-home tests when they suspect that they have a urinary-tract infection. But positive test results are helpful only if a doctor is willing to order a prescription for antibiotics without seeing you first, something many are reluctant to do. And if your self-test is negative but your symptoms continue, you should see a doctor for additional tests, such as a urine culture.

Preventing infection

Some patients are prescribed antibiotics to prevent infections. Women who tend to get UTIs after intercourse may need to take a single dose before sex to prevent flare-ups. Others may need to take preventive regimens daily for six to 12 months. That may help cut the number of UTIs, but it may also increase the risk of adverse effects, including digestive problems, rashes and vaginal fungal infections. Moreover, extended antibiotic use may contribute to the rise of antibiotic-resistant bacteria.

The ability of E. coli to resist such antibiotics as ciprofloxacin (Cipro and similar generics), for example, increased from 3 percent in 2000 to 17 percent in 2010, according to a report last year in the Medical Letter on Drugs and Therapeutics.

Preliminary research has sparked interest in studying whether anti-inflammatories such as ibuprofen (Advil, Motrin and their generics) might help fight UTIs. Other studies have examined whether probiotics, such as lactobacillus strains of bacteria, might bolster the body’s defenses against E. coli.

To try to prevent UTIs, the National Kidney and Urologic Diseases Information Clearinghouse, a service of the National Institutes of Health, offers these recommendations:

●Drink plenty of water to help flush bacteria from the lower urinary tract. Most healthy individuals should try for six to eight eight-ounce glasses a day.

●Don’t “hold it in.” Instead, urinate when the urge arises. And don’t be in a hurry. That can result in incomplete bladder emptying. Infection-causing bacteria can grow when urine stays in the bladder for too long.

●Urinate shortly after sex to flush out bacteria that might have entered the urethra during intercourse.

Copyright 2013. Consumers Union of United States Inc.

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