Here is an “easy explanation” of what the IgG and IgM test is. January 24, 2012September 14, 2012 lisahFor Physicians, Testing I’m sure you have heard people talking about the blood tests for lyme. The terms IgG and IgM get thrown around a lot. Here is an easy to understand explanation of what exactly they mean. http://kidshealth.org/parent/system/medical/test_immunoglobulins.html Share This