Test Catalog

Test ID: LYWB    
Lyme Disease Antibody, Immunoblot, Serum

Useful For Suggests clinical disorders or settings where the test may be helpful

Aiding in the diagnosis of systemic Lyme disease


This test should not be used as a screening assay.

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

See Acute Tick-Borne Disease Testing Algorithm in Special Instructions.

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Lyme disease is caused by the spirochete Borrelia burgdorferi. The spirochete is transmitted to humans through the bite of Ixodes species ticks. Endemic areas for Lyme disease in the United States correspond with the distribution of 2 tick species, Ixodes dammini (Northeastern and upper Midwestern US) and Ixodes pacificus (West Coast US). In Europe, Ixodes ricinus transmits the spirochete.


Lyme disease exhibits a variety of symptoms that may be confused with immune and inflammatory disorders. Inflammation around the tick bite causes skin lesions. Erythema chronicum migrans (ECM), a unique expanding skin lesion with central clearing, which results in a ring-like appearance, is the first stage of the disease. Any of the following clinical manifestations may be present in patients with Lyme disease: arthritis, neurological or cardiac disease, or skin lesions. Neurologic and cardiac symptoms may appear with stage 2 and arthritic symptoms with stage 3 of Lyme disease. In some cases, a definitive distinction between stages is not always seen. Further, secondary symptoms may occur even though the patient does not recall having a tick bite or a rash.


The Second National Conference on the Serologic Diagnosis of Lyme Disease (1994) recommended that laboratories use a 2-test approach for the serologic diagnosis of Lyme disease. Accordingly, specimens are first tested by the more sensitive enzyme immunoassay (EIA). An immunoblot assay is used to supplement positive or equivocal Lyme (EIA). An immunoblot identifies the specific proteins to which the patient's antibodies bind. Although there are no proteins that specifically diagnose B burgdorferi infection, the number of proteins recognized in the immunoblot assay is correlated with diagnosis.


Culture or polymerase chain reaction (PCR) of skin biopsies obtained near the margins of ECM are frequently positive. In late (chronic) stages of the disease, serology is often positive and the diagnostic method of choice. PCR testing also may be of use in these late stages if performed on synovial fluid or cerebrospinal fluid.


Diagnosis of neuroinvasive Lyme disease (ie, neuroborreliosis) can be achieved by determining the Lyme antibody index value using paired serum and cerebrospinal fluid samples (LNBAB / Lyme Central Nervous System Infection IgG with Antibody Index Reflex, Serum and Spinal Fluid).

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

IgG: Negative

IgM: Negative

Reference values apply to all ages

Interpretation Provides information to assist in interpretation of the test results


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 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 Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

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 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 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.

Clinical Reference Recommendations for in-depth reading of a clinical nature

Theel ES: The past, present and (possible) future of serologic testing for Lyme disease. J Clin Microbiol. 2016;54(5):1191-1196

Special Instructions Library of PDFs including pertinent information and forms related to the test