Testing for blood in the urine is usually a painless urine test. Follow-up testing to find the cause of blood in the urine can be more complex. One test to check for problems causing blood in the urine is a computed tomography (CT) scan of the urinary tract, which includes the kidney and bladder. Another test, called cystoscopy, involves inserting a thin tube with a camera into the bladder to check for problems. These tests can cause side effects, such as discomfort, anxiety, and even life-threatening reactions. They are also costly for patients. It is important that these tests are only done when needed.