Has your doctor ordered a tagged or labeled white blood cell scan for you? Here’s what this procedure is used for and what it involves.
There are times when it’s obvious that a person has an infection, but it’s unclear exactly where it’s coming from. To find the source, a doctor often orders a chest x-ray, blood tests, and a urinalysis to check for evidence of infection. Sometimes, despite a thorough search, the source of the infection can’t be found. That’s when a special test called a tagged or labeled white blood cell scan may be helpful.
What is a Tagged or Labeled White Blood Cell Scan?
This is a test used to find hidden sources of infection. When there’s an infection, white blood cells are called to the site of the infection to fight it. This test tracks exactly where the blood cells go, so the source of the infection can be identified. It basically involves tagging white blood cells that are removed from the body with a special radioactive tracer that lights up when scanned with a special camera. The labeled white blood cells are then put back into the body, and the entire body is scanned. This allows the infection to be localized so it can be treated.
How Is a Labeled White Blood Cell Scan Performed?
Blood is taken from a vein and the white blood cells are separated out and mixed with a special radioactive tag. The white blood cells that are tagged are injected back into the body and allowed sufficient time to reach the site of infection. A whole body scan is then performed which picks up the radiation from the tagged white blood cells and helps the doctor locate where the infection is coming from. The scan is usually done on an outpatient basis and requires no anesthesia. It can be a lengthy procedure since once the white blood cells are injected; you may have to return several times for scanning.
Are There Risks Associated with a Labeled White Blood Cell Scan?
The biggest risk of a tagged white blood cell scan is an allergic reaction to the radioactive label which – in extreme cases – can lead to serious symptoms such as a drop in blood pressure and even death. Fortunately, this isn’t common. There’s also the risk associated with radiation exposure. The amount of radioactive tagging material used for this procedure is very small – only a little higher than what you’d get from a standard x-ray. The camera used for scanning only detects radiation – it doesn’t emit it. Other risks include bruising, infection, or bleeding at the injection sites when blood is taken and re-injected. It’s important not to take any antibiotics prior to this procedure since it can alter the results.
The Bottom Line?
Tagged or labeled white blood cell scans involve exposure to small amounts of radiation, but they can help to find sources of infection that might otherwise be difficult to locate. Not treating an infection can be life threatening which should justify the use of this test when necessary. The good news is that this procedure requires no anesthesia and involves no pain other than the needle stick that comes with drawing the blood and injecting it back into the body.