Urinary Tract Infection (UTI)
The urinary tract physiology and function
The urinary tract system makes and stores urine, one of the body’s liquid waste products. Urine production takes place in the kidneys, which make 1.5 to 2 quarts of urine every day by removing waste and water from the blood. From the kidneys, urine travels down two narrow tubes called ureters. It is then stored in a balloon-like container called the bladder.
In an adult, the bladder can hold 10 to 20 ounces of urine (about as much liquid as in one can of soda). The urge to urinate may start when the bladder is about half full.
Urine is carried out of the body through the urethra, a tube that begins at the bottom of the bladder. The end of the urethra is near the top of the vagina in women. In men the urethra passes through the prostate gland and exits at the tip of the penis.
Normal urine contains no bacteria, but bacteria do cover your skin and are present in large numbers in the rectal area and in your bowel movements. Bacteria may, at times, get into the urinary tract (and the urine) and may travel up the urethra into the bladder.
When this happens, the bacteria cause infection and inflammation of the bladder. In other words, they multiply, causing irritation, swelling, and pain. Bladder infection, also called cystitis, is the most common urinary tract infection.
If the bacteria travel upward from the bladder through the ureters and reach the kidneys, you may develop a kidney infection, also known as pyelonephritis. Kidney infections are much less common but often more serious than bladder infections.
Causes of UTI
Some people, mainly women, develop urinary tract infections because they are prone to such infections the way other people are prone to getting coughs or colds. Urinary tract infections are much less common in men and children than in adult women.
A number of factors may increase a person’s risk of getting a urinary tract infection. Some of these factors include:
- Having certain diseases (such as diabetes) or an abnormal urinary system.
- Recently having had a medical instrument inserted into the urethra.
- Sexual contact.
A urinary tract infection in a man or child may be the sign of an abnormal urinary tract. For this reason, when men or children are found to have a urinary tract infection, they may be referred to a urologist (a specialist in diseases of the urinary system and the male reproductive system) for additional tests and x-rays.
During a urinary tract infection, the lining of the bladder and urethra becomes irritated just as the inside of the nose or throat does during a cold. The irritation can cause pain in the abdomen and pelvic area and may create the constant sensation of needing to empty the bladder.
The need to urinate may seem urgent, but trying to do so may produce only a few drops of urine. In addition, there may be a burning sensation during urination. It may even be hard to control, and some urine may leak onto clothing. Sometimes the urine has an unpleasant odor or a cloudy look. At times, bladder infections may also cause low back pain, fever, or chills.
Kidney infections produce fever and back pain much more commonly than do bladder infections. If a kidney infection is not treated promptly, the bacteria may spread to the bloodstream and cause a life-threatening infection.
In an infant or young child, the signs of a urinary tract infection may not be clear, especially if the child is too young to describe just how he or she feels. Instead, the child may be irritable, not eat as much as usual, have a fever or loose bowel movements, or just not seem healthy. If the symptoms last more than a day, it is probably time to see a doctor.
Anyone noticing such symptoms in a young child should probably check with a doctor. If there is blood in the urine, a child or adult should see a doctor right away. Because bloody urine is not normally caused by an infection, it may mean a different urinary tract problem.
A doctor first looks for signs of an infection by examining urine samples under a microscope. If an infection is present, the physician may also perform a urine culture, a process in which bacteria from infected urine are grown in a laboratory.
The germs can then be identified and tested to see which drugs will provide the most effective treatment. It often takes a day or two, however, to complete this testing.
Urinary tract infections are treated with antibiotics (infection-fighting drugs), generally taken by mouth. The doctor chooses a drug formulated to treat the bacteria most likely to be causing the infection. Then, once the test results are in, the doctor may switch the patient to another antibiotic, one that is more effective against the particular bacteria found in the urine.
The number of days the patient takes the medication and the number of doses taken each day depend, in part, on the type of infection and its severity. At minimum, medication has to be taken for at least two to three days and possibly for as long as several weeks. The daily treatment schedule depends on the specific drug prescribed. It may call for a single dose each day or up to four daily doses.
A few doses of the antibiotic may relieve the need to urinate often and most of the pain from a bladder infection. It may be several days, however, before the bladder infection and its symptoms vanish completely. In any case, it is important to take medications as prescribed and not to stop them simply because the symptoms have gone away. Unless urinary tract infections are fully treated, they frequently return.
Anyone with a urinary tract infection should drink fluids whenever he or she is thirsty. It is not necessary to drink large amounts, but everyone should make certain that the body has the liquid it needs.
If the urinary tract infection is severe, it may involve the kidneys. In that case, antibiotic drugs may have to be injected. Hospital treatment with medication given intravenously (injected directly into the bloodstream) is sometimes necessary.
Preventing urinary tract infections
The following are steps to reduce the risk of a urinary tract infection:
- Don’t postpone – urinate when you feel the urge.
- Don’t rush – take your time when you urinate to empty your bladder completely.
- Respond to your body’s signals of thirst by drinking enough water or other liquids every day.
- Urinate after having sex. (Of course, using condoms during intercourse – practicing safe sex – is wise for many reasons.)
Consult your doctor at the first sign of a problem. Urinary tract infections are very common, and they are easiest to treat if caught before they become severe or spread beyond the bladder.
This information is provided largely by the Bladder Health Council, c/o American Foundation for Urologic Disease. For more information call 1-800-242-2383.
Facts about urinary tract infections
- Every year, 8 to 10 million visits to doctors occur because of urinary tract infections.
- The bacteria that cause urinary tract infections are treated with bacteria-fighting drugs called antibiotics.
- Women are usually more prone to urinary tract infections than men or children are.
- One to 2 percent of children develop urinary tract infections.
- Young children have the greatest risk for kidney damage due to urinary tract infections.
- Certain people who get one or more urinary tract infections may need further testing to make sure that they do not have other health problems.
FAQs about UTI
Will I need further tests after the infection is gone?
Once an infection has cleared, a doctor may recommend additional tests. The tests are performed to assure that there are no abnormalities in the urinary tract that might result in kidney damage from urinary tract infections. Certain types of patients are most likely to need the tests. These include:
- Young children
- Anyone with urinary tract infections that are frequent or won’t go away with treatment
- Anyone who has had fever with the infection
- Anyone who have had blood in the urine
What else can cause similar symptoms?
The symptoms of a urinary tract infection may resemble those of other urinary tract diseases. If no infection can be found or the infection won’t go away, a primary-care doctor may refer the patient to a urologist to find out why. Other problems that a urologist may look for are:
- Urethritis may be either an inflammation or an infection of the urethra. When infection is present in the urethra, the condition often is due to bacteria passed by sexual contact.
- Interstitial cystitis is a bladder irritation found mainly in adult women; its cause is not known.
- Urinary stones sometimes develop in the bladder, irritating it and causing symptoms similar to those of a urinary tract infection. On occasion, the stones have bacteria inside that trigger hard-to-cure infections.
- Bladder tumors (cancerous or noncancerous growths), when present, may irritate the bladder. The symptoms often include a frequent need to urinate and possibly blood in the urine.
- Prostatitis is an inflammation or infection of the male gland, the prostate, which surrounds the urethra just below the bladder. In adult males, prostate disorders may cause symptoms that resemble those of urinary tract infections.
Do urinary tract infections have long-term effects?
Urinary tract infections in most adults can be successfully treated without causing long-term problems.
Young children have the greatest risk for kidney damage from urinary tract infections. Such damage may lead to poor kidney function, high blood pressure, and other problems. For this reason, it is important that children with urinary tract infections receive prompt treatment and careful checkups.
Pregnant women with a history of repeated urinary tract infections should have their urine tested often. Urinary tract infections during pregnancy can cause serious kidney infections in the mother and possible risks for the baby.
Contact us if you are experience urinary tract infection symptoms to schedule an appointment with our one of our board certified urologists in the San Francisco East Bay Area.