DefinitionA white blood cell (WBC) scan is an imaging test that uses a radioactive substance (called a tracer) to look for areas of infection or inflammation in the body.See also: Nuclear scanAlternative NamesLeukocyte scanHow the test is performedBlood will be taken from one of your veins. White blood cells are separated from the rest of the blood sample and then mixed with a small amount of a radioactive material (radioisotope) called indium-111. The cells with the radioactive material are considered "tagged."About 2 or 3 hours later, the tagged white blood cells are returned to your body through injection into a vein. The tagged cells gather in areas of inflammation or infection.Approximately 6 to 24 hours later, your body is scanned. You lie on a table. The scanner looks like an x-ray