Current practices in the diagnosis of Lyme disease

Lyme disease (LD) is the most prevalent vector-borne disease in the Northern Hemisphere. The bacterial pathogen responsible for the disease is transmitted to humans and other mammals via the arthropod vector Ixodes spp. whose hematophagy lends itself to the acquisition and transmission of this pathogen. The spirochete pathogen responsible for LD belongs to the genus Borrelia burgdorferi sensu lato complex, who can be found in North America, South America, Eurasia, and Africa. The initial clinical presentation of LD typically manifests with an erythema migrans skin lesion (bull's-eye rash), and if left untreated, can develop into disseminated LD that can be accompanied by neuritis, meningitis, carditis, and/or arthritis. Diagnosis of LD is typically done via serological testing in the clinical laboratory. Advances in this area include the characterization and refinement of antigen targets utilized by immunoassays, more recent expansion of the testing algorithm to allow for the use of immunoassays over immunoblots, and the development of highly sensitive assays that readily allow for automation. Research into future directions for diagnostic testing in the clinical laboratory include the application of transcriptomics, proteomics, and metabolomics, many of which demonstrate promise for potential future application. Each of these areas will be discussed in detail to provide a broad understanding of the disease process, the diagnostic testing modalities currently available to the clinical laboratory, and where future research may lead one day.