Borrelia burgdorferi Antibody, IgG by Immunoblot

This test should be used for confirmation of an equivocal or positive B. burgdorferi Total Antibodies, IgG and/or IgM test performed on patients greater than 4 weeks after disease onset. A negative result indicates that the immunoblot evaluation for the Lyme antibody demonstrates no antibodies unique to B. burgdorferi and is, therefore, not supportive of Lyme disease.

A positive result indicates that the immunoblot evaluation for B. burgdorferi antibody is consistent with the presence of antibody produced by patients in response to infection by B. burgdorferi and suggests the presence of Lyme disease. Although the test has been shown to have a high degree of reliability for diagnostic purposes, laboratory data should always be correlated with clinical findings.

Current CDC recommendations for the serological diagnosis of Lyme disease are to screen with a polyvalent ELISA test and confirm equivocals and positives with immunoblot. Both IgM and IgG immunoblots should be performed on samples obtained less than 4 weeks after appearance of erythema migrans. Only IgG immunoblot is to be performed on samples greater than 4 weeks after disease onset. IgM immunoblot in the chronic stage is not recommended and does not aid in the diagnosis of neuroborreliosis or chronic Lyme disease.