The Lyme disease blood test looks for antibodies in the blood to the bacteria that causes Lyme disease. The test is used to help diagnose Lyme disease.
Lyme disease is caused by bacteria called Borrelia burgdorferi. Blacklegged ticks carry these bacteria. The ticks pick up the bacteria when they bite mice or deer that are infected with Lyme disease. You can get the disease if you are bitten by an infected tick, mostly in northeastern states and on the West Coast. The good news is that usually a tick has to be attached to your body for 24 to 36 hours to infect you. The bad news is that blacklegged ticks are so small they're almost impossible to see.
IgM:
IgM antibodies to Borrelia burgdorferi may be detectable within 1 to 2 weeks following the tick bite; they usually peak during the third to sixth week after disease onset, and then demonstrate a gradual decline over a period of months. IgM antibody may persist for months following completion of treatment. IgM antibody results against B burgdorferi should only be considered during the 30 days following exposure and symptom onset.
Negative specimens typically demonstrate antibodies to fewer than 2 of the 3 significant B burgdorferi proteins. Additional specimens should be submitted in 2 to 3 weeks if B burgdorferi exposure has not been ruled out.
IgG:
IgG antibodies to B burgdorferi can be detected approximately 2 weeks after onset of disease and can remain detectable for months to years following completion of therapy.
Normal specimens and false-positive enzyme immunoassay (EIA) specimens generally have antibodies to 4 or fewer proteins. Except for early patients, antibodies from patients with Lyme disease generally bind to 5 or more proteins.
Cautions:
The immunoblot result may be negative in specimens that are weakly positive by enzyme immunoassay (EIA) or in patients with early Lyme disease.
Test results should be used in conjunction with clinical evaluation and information related to tick exposure.
A negative test result does not necessarily rule-out current or recent infection. The specimen may have been collected before demonstrable antibody developed. Patients with early disease often have serum antibody titers below the diagnostic threshold for several weeks following disease onset.
Test results from patients who are immunosuppressed and pregnant women may be difficult to interpret.
Positive test results may not be valid in persons who have received blood or blood product transfusions within the past several months.
Antibiotic therapy administered early following exposure or disease onset may suppress the antibody response to the point that diagnostic threshold levels are never attained.
Lyme disease serology should not be used for monitoring treatment response, as IgG can remain detectable for years post-resolution of infection.
False-positive reactions may occur with patients with other spirochetal diseases (syphilis, yaws, pinta, relapsing fever, or leptospirosis), recent Epstein-Barr virus infection (ie, infectious mononucleosis), influenza, autoimmune disorders (eg, present of extractable nuclear antigens: ENA), multiple sclerosis, or amyotrophic lateral sclerosis.
Lyme Total Antibody CIA
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