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KEY POINTS ABOUT SEROLOGICAL TESTING FOR
LYME DISEASEIMUGEN offers an antibody or serological profile for B. burgdorferi (Bb) infection.
The first test is called antibody capture enzyme immunoassay (EIA) - this is a refinement/improvement of traditional ELISA testing. The goal of this sophisticated methodology is to maximize test sensitivity, especially for early infection.
IMUGEN tests for and reports capture EIA results for three antibody isotypes - IgM, IgG, & IgA. Each of these values contributes significantly to overall test performance, and allows us to make confident statements about certain features of the Lyme infection in your patient.
The second test is the Western Blot (WB), or immunoblot - focusing on IgG. IMUGEN does not perform IgM Western blotting because of major limitations in test sensitivity and specificity, which more often than not causes confusion and contributes nothing useful for the clinician in trying to determine whether or not a patient has Lyme disease.
IgG WB becomes positive only after weeks of Bb infection; therefore it is not - when used alone - sensitive for early infection. There are distinctive patterns of "bands" which correspond to different stages of Lyme disease, allowing this test to assist considerably in distinguishing earlier from later Bb infection, and to allow is to comment as to whether a patient's chronic symptoms are consistent with Lyme disease or not. IMUGEN offers ten years of expertise in correlating such patterns of immunoblot reactivity with clinical presentations.
The combination of EIA and WB maximizes serological test information. We archive every specimen for a minimum of five years, and these retained samples are available to run concurrently with recent specimens to compare results and learn about the progressor resolution of the Bb infection.
Both EIA and WB are available to test with newer strains of Bb which lack OspA expression. This allows us to easily distinguish real Bb infection from exposure to Lyme vaccine.
The most common sources of error and confusion we see are:
The failure to appreciate the distinct performance of EIA in earlier Lyme disease, and of WB in staging Lyme disease
The use of IgM WB, especially in patients with symptoms of greater than 1 month's duration
The failure to appreciate the relatively poor specificity (i.e. considerable number of false positives) of the traditional commercially available ELISA tests
Please feel free to call our professional staff with questions on Lyme disease testing in general, or on any specific patient results.
220 Norwood Park South
Norwood, MA 02062
1-800-246-8436
1-781-255-0770