Urinary Tract Infections in Men

Urinary tract infections are a serious health problem affecting millions of men each year.

Infections of the urinary tract are the second most common type of infection in the body. Urinary tract infections (UTIs) account for about 8.3 million doctor visits each year.*

Approximately 20% of all UTIs occur in men. Between 1988 and 1994, the overall lifetime prevalence of UTI in men was estimated to be 13,689 cases per 100,000 adult men, based on the National Health and Nutrition Examination Survey.

Rates of UTI increased with age and were 1.5 times higher in African American men than in other racial/ethnic groups such as Caucasian or Hispanic. Asian men had the lowest rates of inpatient hospitalization for UTI care, followed by Hispanics and Caucasians. African American men had the highest rates.

The causes of UTI's in men

Normally, urine is sterile. It is usually free of bacteria, viruses, and fungi but does contain fluids, salts, and waste products. An infection occurs when tiny organisms, usually bacteria from the digestive tract, cling to the opening of the urethra and begin to multiply. The urethra is the tube that carries urine from the bladder to outside the body. Most infections arise from one type of bacteria, Escherichia coli (E. coli), which normally lives in the colon.

In many cases, bacteria first travel to the urethra. When bacteria multiply, an infection can occur. An infection limited to the urethra is called urethritis. If bacteria move to the bladder and multiply, a bladder infection, called cystitis, results. If the infection is not treated promptly, bacteria may then travel further up the ureters to multiply and infect the kidneys. A kidney infection is called pyelonephritis.

Microorganisms called Chlamydia and Mycoplasma may also cause UTIs in men, but these infections tend to remain limited to the urethra and reproductive system. Unlike E. coli, Chlamydia and Mycoplasma may be sexually transmitted, and infections require treatment of both male and female partners.

The urinary system is structured in a way that helps ward off infection. The ureters and bladder normally prevent urine from backing up toward the kidneys, and the flow of urine from the bladder helps wash bacteria out of the body. In men, the prostate gland produces secretions that slow bacterial growth and immune defenses also prevent infection. But despite these safeguards, infections still occur.

Bladder outlet obstruction due to benign prostatic hyperplasia (BPH) may be associated with urinary stasis. Even though a causal relationship has been difficult to prove, chronic prostatic obstruction is thought to increase the risk of UTI in older men with BPH.

Men who engage in insertive anal intercourse are more likely to become infected, as are men who are uncircumcised are more likely to get an infection, because the bacteria can build up much more easily in the folds of the extra skin.

The Risk Factor for Men

Some men are more prone to getting a UTI than others. Any abnormality of the urinary tract that obstructs the flow of urine (a kidney stone, for example) sets the stage for an infection. An enlarged prostate gland also can slow the flow of urine, thus raising the risk of infection.A common source of infection is catheters, or tubes, placed in the urethra and bladder. A man who cannot void or who is unconscious or critically ill often needs a catheter that stays in place for a long time. Some men, especially the elderly or those with nervous system disorders who lose bladder control, may need a catheter for life. Bacteria on the catheter can infect the bladder, so hospital staff take special care to keep the catheter clean and remove it as soon as possible.

Men with diabetes have a higher risk of a UTI because of changes in the immune system. Any other disorder that suppresses the immune system raises the risk of a urinary infection. UTIs may occur in infant boys who are born with abnormalities of the urinary tract, which sometimes need to be corrected with surgery. UTIs are more rare in boys and young men than girls and young women.

Recurrent Infections in Men

Usually, the latest infection stems from a strain or type of bacteria that is different from the infection before it, indicating a separate infection. Even when several UTIs in a row are due to E. coli, slight differences in the bacteria indicate distinct infections.

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 NIH-funded study found that bacteria formed a protective film on the inner lining of the bladder in mice. If a similar process can be demonstrated in humans, the discovery may lead to new treatments to prevent recurrent UTIs.

UTIs in men are often a result of an obstruction-for example, a urinary stone or enlarged prostate-or from a medical procedure involving a catheter. The first step is to identify the infecting organism and the drugs to which it is sensitive. Usually, doctors recommend lengthier therapy in men than in women, in part to prevent infections of the prostate gland.

Prostate infections (chronic bacterial prostatitis) are harder to cure because antibiotics are unable to penetrate infected prostate tissue effectively. For this reason, men with prostatitis often need long-term treatment with a carefully selected antibiotic. UTIs in older men are frequently associated with acute bacterial prostatitis, which can have serious consequences if not treated urgently.

The Symptoms of UTI

Not every man with a UTI has symptoms, but most men get at least some symptoms. These may include a frequent urge to urinate and a painful, burning feeling in the area of the bladder or urethra during urination. It is not unusual to feel bad all over-tired, shaky, washed out-and to feel pain even when not urinating. Some men have experienced the feeling of a fullness in the rectum. It is common for a man with a urinary infection to complain that, despite the urge to urinate, only a small amount of urine is passed. The urine itself may look milky or cloudy, even reddish if blood is present. Normally, a UTI does not cause fever if it is in the bladder or urethra. A fever may mean that the infection has reached the kidneys. Other symptoms of a kidney infection include pain in the back or side below the ribs, nausea, or vomiting.

UTI Diagnosis

To find out whether you have a UTI, your doctor will test a sample of urine for pus and bacteria. You will be asked to give a "clean catch" urine sample by washing the genital area and collecting a "midstream" sample of urine in a sterile container. This method of collecting urine helps prevent bacteria around the genital area from getting into the sample and confusing the test results. Usually, the sample is sent to a laboratory, although some doctors' offices are equipped to do the testing.

In the urinalysis test, the urine is examined for white and red blood cells and bacteria. Then the bacteria are grown in a culture and tested against different antibiotics to see which drug best destroys the bacteria. This last step is called a sensitivity test.

Some microbes, like Chlamydia and Mycoplasma, can be detected only with special bacterial cultures. A doctor suspects one of these infections when a man has symptoms of a UTI and pus in the urine, but a standard culture fails to grow any bacteria.

When an infection does not clear up with treatment and is traced to the same strain of bacteria, the doctor may order some tests to determine if your system is normal. One of these tests is an intravenous pyelogram, which gives x-ray images of the bladder, kidneys, and ureters. An opaque dye visible on x-ray film is injected into a vein, and a series of x rays is taken. The film shows an outline of the urinary tract, revealing even small changes in the structure of the tract.

If you have recurrent infections, your doctor also may recommend an ultrasound exam, which gives pictures from the echo patterns of soundwaves bounced back from internal organs. Another useful test is cystoscopy. A cystoscope is an instrument made of a hollow tube with several lenses and a light source, which allows the doctor to see inside the bladder from the urethra.

UTI Treatment

UTIs are treated with antibacterial drugs. The choice of drug and length of treatment depend on the patient's history and the urine tests that identify the offending bacteria. The sensitivity test is especially useful in helping the doctor select the most effective drug. The drugs most often used to treat routine, uncomplicated UTIs are trimethoprim (Trimpex), trimethoprim/sulfamethoxazole (Bactrim, Septra, Cotrim), amoxicillin (Amoxil, Trimox, Wymox), nitrofurantoin (Macrodantin, Furadantin), and ampicillin (Omnipen, Polycillin, Principen, Totacillin). A class of drugs called quinolones includes four drugs approved in recent years for treating UTI. These drugs include ofloxacin (Floxin), norfloxacin (Noroxin), ciprofloxacin (Cipro), and trovafloxin (Trovan).

Often, a UTI can be cured with 1 or 2 days of treatment if the infection is not complicated by an obstruction or other disorder. Still, many doctors ask their patients to take antibiotics for a week or two to ensure that the infection has been cured. Single-dose treatment is not recommended for some groups of patients, for example, those who have delayed treatment or have signs of a kidney infection, patients with diabetes or structural abnormalities, or men who have prostate infections. Longer treatment is also needed by men with infections caused by Mycoplasma or Chlamydia, which are usually treated with tetracycline, trimethoprim/sulfamethoxazole (TMP/SMZ), or doxycycline. A followup urinalysis helps to confirm that the urinary tract is infection-free. It is important to take the full course of treatment because symptoms may disappear before the infection is fully cleared.

Severely ill men with kidney infections may be hospitalized until they can take fluids and needed drugs on their own. Kidney infections generally require several weeks of antibiotic treatment. Researchers at the University of Washington found that 2-week therapy with TMP/SMZ was as effective as 6 weeks of treatment with the same drug in women with kidney infections that did not involve an obstruction or nervous system disorder. In such cases, kidney infections rarely lead to kidney damage or kidney failure unless they go untreated.

Various drugs are available to relieve the pain of a UTI. A heating pad may also help. Most doctors suggest that drinking plenty of water helps cleanse the urinary tract of bacteria. During treatment, it is best to avoid coffee, alcohol, and spicy foods. And one of the best things a smoker can do for his bladder is to quit smoking. Smoking is the major known cause of bladder cancer. Complicated Infections

Curing infections that stem from a urinary obstruction or other systemic disorders depends on finding and correcting the underlying problem, sometimes with surgery. If the root cause goes untreated, this group of patients is at risk of kidney damage. Also, such infections tend to arise from a wider range of bacteria, and sometimes from more than one type of bacteria at a time.

Sources

The National Institute of Health

(Book)-Urinary Tract Infection in Men
Tomas L. Griebling, MD
Associate Professor & Vice Chair of Urology
University of Kansas
Kansas City, Kansas

*Ambulatory Care Visits to Physician Offices, Hospital Outpatient Departments, and Emergency Departments: United States, 1999-2000. Vital and Health Statistics. Series 13, No. 157. Hyattsville, MD: National Center for Health Statistics, Centers for Disease Control and Prevention, U.S. Dept. of Health and Human Services; September 2004.