Urinary tract infection (UTI) is a common infection that usually occurs when bacteria enter the opening of the urethra and multiply in the urinary tract. The urinary tract includes the kidneys, the tubes that carry urine from the kidneys to the bladder (ureters), the bladder, and the tube that carries urine from the bladder (urethra). The special connection of the ureters at the bladder help prevent urine from backing up into the kidneys, and the flow of urine through the urethra helps to eliminate bacteria.
Escherichia coli (E. coli) causes about 80% of urinary tract infections (UTIs) in adults. These bacteria are normally present in the colon and may enter the urethral opening from the skin around the anus and genitals. Women may be more susceptible to UTI because their urethral opening is near the source of bacteria (e.g., anus, vagina) and their urethra is shorter, providing bacteria easier access to the bladder.
Other bacteria that cause urinary tract infections include Staphylococcus saprophyticus (5 to 15% of cases), Chlamydia trachomatis, and Mycoplasma hominis. Men and women infected with chlamydia trachomatis or mycoplasma hominis can transmit the bacteria to their partner during sexual intercourse, causing UTI.
Sexual intercourse triggers UTI in some women, for unknown reasons. Women who use a diaphragm develop infections more often, and condoms with spermicidal foam may cause the growth of E. coli in the vagina, which may enter the urethra.
Urinary catheterization (i.e., insertion of a small tube into the bladder through the urethra to drain urine) can also cause UTI by introducing bacteria into the urinary tract. The risk for developing a UTI increases when long-term catheterization is required.
Symptoms of lower UTI (e.g., cystitis, urethritis) in adults can include the following:
- Back pain
- Blood in the urine (hematuria)
- Cloudy urine
- Inability to urinate despite the urge
- Frequent need to urinate
- General discomfort (malaise)
- Painful urination (dysuria)
If you have any of these symptoms please contact us to schedule an appointment at
Treatment for Infections in the Lower Urinary Tract
Bladder infections, kidney infections, and other urinary tract infections are often treated with antibacterial drugs. The type of drug used and the duration of treatment depend on the type of bacteria.