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"What does blood test for a swollen lymph node test or check for?"

ZocdocAnswersWhat does blood test for a swollen lymph node test or check for?


For instance, if someone got a blood test because of a swollen lymph node, would the results show if that person was HIV positive, had a certain type of cancer, or show if it was just caused by a cold?


There are many different tests that can be run for someone who has a swollen lymph node, and certainly the history surrounding the swelling is important to understand. One of the most likely tests for your doctor to have ordered is a CBC, or complete blood count. This will show levels of red blood cells, platelets, and infection fighting cells in your body. This is important if you have a swollen lymph node for several reasons. First, if your level of infection fighting cells is high, this can often be a sign of an infection, which would lead your doctor to suspect that perhaps there is a smoldering infection somewhere that needs to be treated to make sure that you can get back to your usual state of health. Additionally, this same test can tell you if other parts of your blood cells, say your white blood cells (which usually fight infection, as above) or your platelets (which help with clotting) are abnormally elevated which could indicate different types of blood malignancies. There are, of course, many other tests that your doctor could order that could give more specific information depending on what he or she was thinking. Please speak with your doctor about your questions.

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