An ELISA and Western blot testing are the leading tests for detecting Lyme disease. The lab must examine a series of blot and determine if the pattern is characteristic of Lyme disease.

The laboratory performs two types of Western blots, the IgG and IgM. The IgG pattern indicates late Lyme disease and IgM indicates early Lyme disease.

There are many people with Lyme disease who do not hav a positive Western Blot test. The Western blot is not sensitive. Most Lyme disease patients evaluated for the National Institute of Health (NIH) trial a Columbia did not have a positive IgG Western blot test.