UTIs are caused by bacteria. The bacteria invade the urinary system and multiply. The infection can occur in any part of the urinary system, but usually starts in the urethra. The urethra is a tube that carries the urine out of the body.

In most cases, bacteria begins growing in the urethra. The bacteria comes most often from the digestive tract and rectal area. They cling to the opening of the urethra and begin to multiply. An infection only in the urethra is called urethritis . From there, bacteria move to the bladder, causing a bladder infection ( cystitis ). If the infection is not treated right away, bacteria may then go up the ureters. Ureters are two tubes that carry urine from the kidneys to the bladder. From there the infection can continue into the kidneys ( pyelonephritis ).

Most infections are caused by one type of bacteria called E. coli . E. coli normally lives in the colon. In women, since the rectum and urethra are fairly close to each other, the bacteria can move into the urethra. This makes women more prone to UTIs than men.

UTIs can also be sexually transmitted. This type of infection usually does not spread past the urethra. Both partners need to be treated.

These factors increase your chance of developing a UTI. Tell your doctor if you have any of these risk factors:

• Sex: female
• Being sexually active
• Using a diaphragm for birth control
• Menopause
• Diabetes
• Kidney stones
• Enlarged prostate
• Weak immune system
• Abnormalities of the urinary system, including vesicoureteral reflux , polycystic kidneys
• Paraplegia
• Sickle-cell anemia
• History of kidney transplant
• Bladder catheter in place, or recent device inserted into the urinary system
• Pregnancy

If you have any of these symptoms do not assume they are due to a UTI. These symptoms may be caused by other conditions. Tell your doctor if you have any of these:

• Frequent and urgent need to urinate
• Passing small amounts of urine
• Pain in the abdomen or pelvic area
• Burning sensation during urination
• Cloudy, bad-smelling urine
• Increased need to get up at night to urinate
• Blood in the urine
• Leaking urine
• Low back pain or pain along the side of the ribs
• Fever and chills
• Nausea and poor appetite

Bloody urine, low back pain, high fever, and chills are all signs of a kidney infection . Call your doctor right away if you have these symptoms.

The doctor will ask about your symptoms and medical history. A physical exam will also be done. A sample of your urine will also be tested for blood, pus, and bacteria.

Children and men who have UTIs may need more testing. There may be structural problems of the kidneys, bladder, or tubes that make them likely to have an infection.

UTIs are treated with antibiotic drugs. Standard medical care for a UTI includes taking antibiotics for three days. You most likely will start to feel better after a day or two. However, it is important that you continue to take the entire course of medication.

You may be asked to have your urine checked after you finish taking the antibiotics. This is to make sure that the infection is truly gone.

If you still experience recurrent infections, you may be referred to a specialist.

Pyridium is a medicine that decreases pain and bladder spasm. It may turn your urine, and sometimes your sweat, an orange color.

In some cases, severe UTIs are treated with intravenous or intramuscular antibiotics. Researchers, though, found that oral antibiotics appear to be as effective in treating UTIs as other treatments.

If you are diagnosed with a UTI, follow your doctor's instructions .