Health

Urinary Tract Infections: Diagnosis & Treatment

Urinary Tract Infections: Treatment Help

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 only be detected with special bacterial cultures. A doctor suspects one of these infections when a person 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 will order a test that makes images of the urinary tract. One of these tests is an intravenous pyelogram (IVP), 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 are 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.


Treatment

An uncomplicated UTI can be cured with 1 or 2 days of treatment.

UTI’s are treated with antibacterial drugs. The choice of drug and length of treatment depends 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 UTI’s are trimethoprim (Trimpex), trimethoprim/sulfamethoxazole (Bactrim, Septra, Cotrim), amoxicillin (Amoxil, Trimox, Wymox), nitrofurantoin (Macrodantin, Furadantin), and ampicillin.

Often, a UTI can be cured with 1 or 2 days of treatment if the infection is not complicated by an obstruction or nervous system 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 patients 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 patients 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 or a warm bath may also help. Most doctors suggest that drinking plenty of water helps cleanse the urinary tract of bacteria. For the time being, it is best to avoid coffee, alcohol, and spicy foods. (And one of the best things a smoker can do for his or her bladder is to quit smoking. Smoking is the major known cause of bladder cancer.)

Recurrent Infections in Women

Women who have frequent recurrences may benefit from preventive therapy.

About 4 out of 5 women who have a UTI get another in 18 months. Many women have them even more often. A woman who has frequent recurrences (three or more a year) should ask her doctor about one of the following treatment options:

  • Take low doses of an antibiotic such as TMP/SMZ or nitrofurantoin daily for 6 months or longer. (If taken at bedtime, the drug remains in the bladder longer and may be more effective.) NIH-supported research at the University of Washington has shown this therapy to be effective without causing serious side effects.

  • Take a single dose of an antibiotic after sexual intercourse.

  • Take a short course (1 or 2 days) of antibiotics when symptoms appear.

Dipsticks that change color when an infection is present are now available without prescription. The strips detect nitrite, which is formed when bacteria change nitrate in the urine to nitrite. The test can detect about 90 percent of UTI’s and may be useful for women who have recurrent infections.

Doctors suggest some additional steps that a woman can take on her own to avoid an infection:

  • Drink plenty of water every day. Some doctors suggest drinking cranberry juice, which in large amounts inhibits the growth of some bacteria by acidifying the urine. Vitamin C (Ascorbic Acid) supplements have the same effect;

  • Urinate when you feel the need; don’t resist the urge to urinate;

  • Wipe from front to back to prevent bacteria around the anus from entering the vagina or urethra;

  • Take showers instead of tub baths;

  • Cleanse the genital area before sexual intercourse;

  • Avoid using feminine hygiene sprays and scented douches, which may irritate the urethra.

Infections in Pregnancy

A pregnant woman who develops a UTI should be treated promptly to avoid premature delivery of her baby and other risks such as high blood pressure. Some antibiotics are not safe to take during pregnancy. In selecting the best treatments, doctors consider various factors such as the drug’s effectiveness, the stage of pregnancy, the mother’s health, and potential effects on the fetus.

Complicated Infections

Curing infections that stem from a urinary obstruction or nervous system disorder 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.

UTI’s are unusual in men. They usually stem from an obstruction-for example, a urinary stone or enlarged prostate-or 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 recommended lengthier therapy in men than in women, in part to prevent infections of the prostate gland. Prostate infections (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.


Research in Urinary System Disorders

The NIH conducts and supports a variety of research in diseases of the kidney and urinary tract. The knowledge gained from these studies is advancing scientific understanding of why UTI’s develop and is leading to improved methods of diagnosing, treating, and preventing infections.

The National Institute of Diabetes and Digestive and Kidney Diseases, part of the NIH, has established six research centers around the country with the goal of reducing the major causes of kidney and urinary tract diseases through innovative research.