To find out whether a person has a UTI, the health care provider will ask about urinary symptoms and then test a sample of urine for the presence of bacteria and white blood cells, which are produced by the body to fight infection. Because bacteria can be found in the urine of healthy individuals, a UTI is diagnosed based both on symptoms and a laboratory test. The person 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 health care providers offices are equipped to do the testing. For people with recurring infections and patients in the hospital, the urine may be cultured. The culture is performed by placing part of the urine sample in a tube or dish with a substance that encourages any bacteria present to grow. Once the bacteria have multiplied, which usually takes 1 to 3 days, they can be identified. The health care provider may also order a sensitivity test, which tests the bacteria for sensitivity to different antibiotics to see which medication is best for treating the infection.
                
If a person has recurrent UTIs, the health care provider may order some additional tests to determine if the persons urinary tract is normal.
                
Kidney and bladder ultrasound. Ultrasound uses a device, called a transducer, that bounces safe, painless sound waves off organs to create an image of their structure. The procedure is performed in a health care providers office, outpatient center, or hospital by a specially trained technician, and the images are interpreted by a radiologista doctor who specializes in medical imaging; anesthesia is not needed. The images can show abnormalities in the kidneys and bladder. However, this test cannot reveal all important urinary abnormalities or measure how well the kidneys work.
                
Voiding cystourethrogram. This test is an x-ray image of the bladder and urethra taken while the bladder is full and during urination, also called voiding. As the person lies on the x-ray table, a health care provider inserts the tip of a thin, flexible tube called a catheter through the urethra into the bladder. The bladder and urethra are filled with a special dye called contrast medium, to make the structures clearly visible on the x-ray images. The x rays are taken from various angles while the bladder is full of contrast medium. The catheter is then removed and x-ray images are taken during urination. The procedure is performed in a health care providers office, outpatient center, or hospital by an x-ray technician. The technician is supervised by a radiologist while the images are taken. The radiologist then interprets the images. Anesthesia is not needed, but light sedation may be used for some people. This test can show abnormalities of the inside of the urethra and bladder. The test can also determine whether the flow of urine is normal when the bladder empties.
                
Computerized tomography (CT) scan. CT scans use a combination of x rays and computer technology to create three-dimensional (3-D) images. A CT scan may include the injection of contrast medium. CT scans require the person to lie on a table that slides into a tunnel-shaped device where the x rays are taken. The procedure is performed in an outpatient center or hospital by an x-ray technician, and the images are interpreted by a radiologist; anesthesia is not needed. CT scans can provide clearer, more detailed images to help the health care provider understand the problem.
                
Magnetic resonance imaging (MRI). MRI machines use radio waves and magnets to produce detailed pictures of the bodys internal organs and soft tissues without using x rays. An MRI may include an injection of contrast medium. With most MRI machines, the person lies on a table that slides into a tunnel-shaped device that may be open ended or closed at one end; some newer machines are designed to allow the person to lie in a more open space. The procedure is performed in an outpatient center or hospital by a specially trained technician, and the images are interpreted by a radiologist; anesthesia is not needed though light sedation may be used for people with a fear of confined spaces. Like CT scans, MRIs can provide clearer, more detailed images.
                
Radionuclide scan. A radionuclide scan is an imaging technique that relies on the detection of small amounts of radiation after injection of radioactive chemicals. Because the dose of the radioactive chemicals is small, the risk of causing damage to cells is low. Special cameras and computers are used to create images of the radioactive chemicals as they pass through the kidneys. Radionuclide scans are performed in a health care providers office, outpatient center, or hospital by a specially trained technician, and the images are interpreted by a radiologist; anesthesia is not needed. Radioactive chemicals injected into the blood can provide information about kidney function. Radioactive chemicals can also be put into the fluids used to fill the bladder and urethra for x ray, MRI, and CT imaging.
                
Urodynamics. Urodynamic testing is any procedure that looks at how well the bladder, sphincters, and urethra are storing and releasing urine. Most of these tests are performed in the office of a urologista doctor who specializes in urinary problemsby a urologist, physician assistant, or nurse practitioner. Some procedures may require light sedation to keep a person calm. Most urodynamic tests focus on the bladders ability to hold urine and empty steadily and completely. Urodynamic tests can also show whether the bladder is having abnormal contractions that cause leakage. A health care provider may order these tests if there is evidence that the person has some kind of nerve damage.
                
Cystoscopy. Cystoscopy is a procedure that uses a tubelike instrument to look inside the urethra and bladder. Cystoscopy is performed by a doctor in a health care providers office, outpatient facility, or hospital with local anesthesia. However, in some cases, sedation and regional or general anesthesia are needed. Cystoscopy may be used to look for swelling, redness, and other signs of infection.