Urinary Tract Infection (UTI) is a common name for infectious diseases that affect the kidneys and urinary tract.
Background
Infections of the urinary tract are the second most common type of infection in the body and accounts for about 8.3 million doctor visits each year. Women are especially at risk of developing UTIs and it was estimated that one woman in five develops a UTI during her lifetime.
The urinary system consists of the kidneys, ureters, bladder, and urethra. The key elements in the system are the kidneys, a pair of purplish-brown organs located below the ribs toward the middle of the back. The kidneys remove excess liquid and wastes from the blood in the form of urine, keep a stable balance of salts and other substances in the blood, and produce a hormone that aids the formation of red blood cells. Narrow tubes called ureters carry urine from the kidneys to the bladder, a sack-like organ in the lower abdomen. Urine is stored in the bladder and emptied through the urethra.
The average adult passes about a quart and a half of urine each day. The amount of urine varies, depending on the fluids and foods a person consumes. The volume formed at night is about half that formed in the daytime.
Causes
Women tend to get them more often because their urethra is shorter and closer to the anus. Elderly people (especially those in nursing homes) and people with diabetes also get more UTIs due to decreased immunity.
Some children develop UTIs. In boys, they are most common before the first birthday. In young girls, UTIs are most common around age 3, overlapping with the toilet training period. Cystitis in children can be promoted by abnormalities in the urinary tract. Therefore, children with cystitis, especially those under age 5, should be carefully examined to make sure that there are no complications of the condition.
The following risk factors increase the chances of developing a UTI:
- Bowel incontinence;
- Catheterization, for example, in disabled or seriously ill individuals;
- Kidney stones;
- Immobility (for example, during recovery from a hip fracture);
- Menopause;
- Narrowed urethra for example due to strictures;
- Not drinking enough fluids;
- Pregnancy;
- Prostate inflammation or enlargement;
- Multiple sexual partners.
- Using a diaphragm for birth control.
Symptoms
Lower urinary tract infection (cystitis) develops when the lining of the urethra and bladder becomes inflamed and irritated. This results in pain or burning sensation during peeing, more frequent urination (or waking up at night to go to the loo), the sensation of not being able to hold urine, the sensation of not being able to urinate easily or completely (or feeling that you have to urinate but only a few drops of urine come out) and cloudy, bad smelling, or rarely bloody urine. It may be also associated with lower abdominal pain and mild fever and “just not feeling well” (malaise).
Upper urinary tract infection (pyelonephritis) symptoms develop rapidly and may or may not include the symptoms of a lower urinary tract infection. Generalized symptoms such as fever, chills, nausea, vomiting, and flank pain may be present in pyelonephritis.
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 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 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 an 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.
Treatment
A mild urinary tract infection may go away on its own without treatment. However, antibiotics are usually recommended because there is a risk that the infection can spread to the kidneys. Antibiotics are taken by mouth, usually from 3 to 7 days. It is important that you finish all the medication.
Commonly used antibiotics include amoxicillin or augmentin, nitrofurantoin, trimethoprim-sulfamethoxazole and quinolones (should not be used in children). Your doctor may also recommend drugs to relieve the burning pain and urgent need to urinate and to decrease bacteria in your urine such as acidifying medications and Phenazopyridine hydrochloride (Pyridium). In severe cases, a person may require hospital admission for intravenous medication.
Some people have urinary tract infections that keep coming back or that do not go away with treatment. Such infections are called chronic UTIs. If you have a chronic UTI, you may need antibiotics for a long period of time, perhaps as long as 6 months to 2 years, or stronger antibiotics may be prescribed. If a structural (anatomical) problem is causing the infection, surgery may be recommended.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.