A negative result does not exclude the possibility of infection with Borrelia burgdorferi.
A positive result is not definitive evidence of infection with Borrelia burgdorferi. It is possible that other disease conditions, including syphylis, periodontal disease, rheumatoid arthritis, systemic lupus erythematosis, and other autoimmune diseases, may produce artifactual reactivity in the assay.
This test should not be used to screen the general population. The predictive value of the assay is a function of the pretest probability of Lyme disease in the population tested. Hence, only patients with clinical symptoms of Lyme disease or suspected exposure to Borrelia burgdorferi should be tested.
The DiaSorin LIASON® Borrelia burgdorferi assay contains antigens from Borrelia burgdorferi and Borrelia ganinii, known to infect populations in Europe and other parts of the world, but not generally detected in US patients. Results from the second-step Western Blot that only detects B. burgdorferi specific antigens should be interpreted with caution. Treatment of these patients for Lyme disease should be based on clinical manifestations present and patient history, including travel outside of the US.
Potential assay interference due to circulating antibodies against Human Erlichiosis (HE) and Tick Borne Relapsing Fever (TBRF) has been found. Interpret results from these patients with caution.
This assay has been tested with samples from individuals vaccinated with a licensed OspA vaccine (LYMErixa – manufactured by GlaxoSmithKline Biologicals). The performance has not been determined on serum samples from recipients of other Lyme vaccines.
Western blot is not useful as a screening assay. WB may be negative in specimens that are weakly-positive by 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 drawn before demonstrable antibody developed. Patients with early stage disease often have serum antibody titers below the diagnostic threshold for several weeks after onset of disease.
Test results from immunosuppressed patients 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 with the past several months.
Antibiotic therapy early in the first-stage disease may blunt antibody response to the point that diagnostic threshold levels are never attained, making disease difficult to detect through serology.
False-positive reactions may occur with patients with other spirochetal diseases (syphilis, yaws, pinta, relapsing fever, and leptospirosis), influenza, auto-immune disorders, MS and ALS.
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