Lyme Disease Testing

Lyme disease is caused by the bacterium Borrelia burgdorferi and, to a lesser extent, B mayonii. These Borrelia species are transmitted to humans through the bite of an infected blacklegged (deer) tick, Ixodes scapularis, or the western blacklegged tick, I pacificus.

Diagnosis of Lyme disease is made through clinical assessment or clinical assessment supported by laboratory testing. The presence of an erythema migrans (EM) rash is diagnostic of Lyme disease without laboratory investigation.^1,2

Patients who do not develop a rash but have symptoms suggesting Lyme disease, and have been to areas with a high risk of tick exposure, may undergo laboratory testing to help identify the cause of symptoms.^1,2 For more information, see the Quest Diagnostics Clinical Focus “Tick-borne Diseases: Laboratory Support of Diagnosis and Management” available here.    

One example of a molecular test for Lyme disease at Quest is the Lyme Disease (Borrelia spp) DNA, Qualitative Real-Time PCR, Blood (test code 15777).  Amplification of Borrelia genomic DNA from blood, fluids or tissues can support the diagnosis of Lyme disease.  Click here for a list of this and other molecular tests for Lyme disease at Quest. 

Serologic testing is the principal means of laboratory diagnosis of Lyme disease. Quest offers testing in accordance with the Centers for Disease Control and Prevention (CDC) guidelines for early/acute Lyme testing.³ When laboratory diagnosis is indicated, current recommendations include using a 2-tier testing approach that begins with a sensitive enzyme immunoassay (EIA), followed by a confirmatory immunoassay for specimens yielding positive or equivocal results.³ In the standard 2-tier test (STTT) algorithm, a Western blot or immunoblot assay is used for confirmation. However, on July 29, 2019, the US Food and Drug Administration (FDA) cleared several Lyme disease serologic assays with new indications for use, which allowed an EIA (rather than immunoblot assay) to be used as the confirmatory test in a modified 2-tier testing (MTTT) algorithm.³ The MTTT algorithm is now considered an acceptable approach for the serologic diagnosis of Lyme disease and may be able to assist in the identification of early Lyme disease within the first 30 days of infection.³

Quest offers test options that use both the STTT and the MTTT algorithm:

• STTT: Lyme Disease Ab with Reflex to Blot (IgG, IgM) (test code 6646)
• MTTT: Lyme Disease Antibody with Reflex to Immunoassay (IgG, IgM) (test code 39733)

Click here for a complete list of additional tests for tick-borne infectious diseases available from Quest. 

The MTTT appears to provide similar or improved sensitivity and specificity compared to the STTT. In a 356-sample retrospective study of a heterogenous cohort, specimens from healthy and disease control (without Lyme disease) subjects and patients characterized as having stage I (early acute), stage II (early disseminated), or stage III (late disseminated) Lyme disease were tested with both the STTT and MTTT approach.⁴ The results are summarized in Table 1. The MTTT methodology showed improved sensitivity relative to STTT for Lyme stages I and II, with statistically comparable sensitivity for stage III Lyme disease; specificity did not differ significantly between the 2 methods.⁴

No, not immediately. Lyme disease develops in stages: the early stage, which is divided into early localized infection, early disseminated, and then a late disseminated infection.¹ Spirochetemia occurs early, with widespread dissemination through tissue and body fluids. However, antibodies usually take at least 2 weeks to develop, so patients may be seronegative within 2 weeks of a suspected tick bite.^1-3 The sensitivity of serologic testing increases markedly with the progression of B burgdorferi infection from early to late Lyme disease.

Identification of Borrelia species DNA in the blood by polymerase chain reaction (PCR) may be useful in the first two weeks of infection.¹

As noted above, serologic tests may yield negative results early during infection, before antibodies have reached detectable levels. In addition, serologic assays may give false-positive results in individuals with other conditions, including ^3,5,6

• Pathogenic spirochetal diseases, such as syphilis, yaws, pinta leptospirosis, relapsing fever, and periodontal disease
• Other bacterial and viral infections, such as Rocky Mountain spotted fever, Epstein-Barr virus, and cytomegalovirus
• Connective tissue autoimmune diseases associated with positivity for anti-nuclear antibody, including rheumatoid arthritis and systemic lupus erythematosus

There is no test to prove cure for Lyme disease. Antibodies frequently persist in the blood for months or even years after the infection is resolved, despite absence of detectable/viable B burgdorferi.⁷ Therefore, antibody tests cannot be used to determine a cure. There is no evidence that antibiotics cause Lyme serology blood tests to become negative following treatment.^3,5,6

No. If a person has persistent antibodies from the first Lyme disease infection, there is no way to know, with the current Lyme serology tests available at Quest, if positivity is due to reinfection or persistence of antibodies from prior infection.^8,9

I scapularis (deer) ticks can also carry other human pathogens that have a high degree of symptom overlap, including Borrelia miyamotoi, Anaplasma phagocytophilum, Ehrlichia chaffeensis, and Babesia microti.^2,10-12  Several studies on co-infected ticks indicate as many as 20% of Ixodid ticks can be coinfected with B burgdorferi and one or more of these other tick-borne human pathogens.^10-12

Molecular tests can be useful to detect these organisms in early/acute stages of infection, when genetic material from the pathogen can be detected but antibodies remain below the limit of detection (LoD) of serologic assays.^2,10-12 Quest offers molecular and/or serological tests for B burgdorferi, B miyamotoi, A phagocytophilum, E chaffeensis, and B microti, individually (see Test Directory for individual test codes) and in 2 panels (Table 2).

For information on trends in tick-borne diseases in the United States, please read the Quest Diagnostics Health Trends Lyme Disease report available at QuestDiagnostics.com/dms/Documents/health-trends/Quest_LymeDiseaseTrendsReport_2018.pdf.

Click here for a list of additional tests for tick-borne infectious diseases at Quest.