A doctor can sometimes diagnose a bladder infection simply by the symptoms. But in order to confirm the diagnosis, the doctor will collect a midstream urine sample to check for bacteria. To avoid contamination from bacteria outside the body, you need to clean the genital area and catch the urine during midstream. The sample will be examined for bacteria and red and white blood cells. The bacteria are tested for sensitivity to find the antibiotic that will most quickly destroy the bacteria.
If your infection does not clear up with a target antibiotic, other tests may be performed to test for physical abnormalities. By injecting a dye into the veins that produces visible images of the bladder, kidney and uterers on an x-ray film, your doctor will see even subtle changes in the urinary tract that could lead to infection.