Your health care professional will determine whether you have a urinary tract infection based on your symptoms, a physical examination and the result of a laboratory test of your urine. You will be asked to urinate into a small cup. The urine will be examined under a microscope for bacteria and for a large amount of white blood cells, which fight infection. A urine culture may be done in which the bacteria in the urine are encouraged to grow. The bacteria can then be identified and may be tested to see which antibiotic drug best kills them. If you are having recurrent symptoms of infections despite treatment, it is important that your urine be cultured BEFORE you are placed on antibiotics. Repeated treatment of presumed infections without urine culture should be avoided.
Some bacteria, such as chlamydia, can only be found with special urine cultures. A health care professional may suspect these infections when a woman has urinary tract infection symptoms, but a standard culture doesn't grow the bacteria.
If you have recurring urinary tract infections, your health care professional may suggest other tests to look for obstructions or other problems that might trap urine in the tract and cause infection:
- Intravenous pyelography (IVP) is a test in which a dye that is visible on an X-ray is injected into a vein. As the dye enters the kidneys, ureters and bladder, several X-rays are taken.
- A computed tomography scan (CT scan), a type of X-ray test used to capture images of different structures in the body, may be appropriate in some patients instead of, or in addition to, an IVP.
- Ultrasound uses sound waves to produce images of the urinary tract. No radiation is involved in this test.
- Cystoscopy is a test using a thin telescope-like instrument that allows your health care professional to see inside the urethra and bladder and examine them for problems.