LABORATORY DIAGNOSTIC METHODS IN LYME BORRELIOSIS

With the discovery of Borrelia burgdorferi in 19821 the development of specific laboratory tests for Lyme borreliosis became possible. The need for appropriate and reliable diagnostic tests is obvious considering that currently every year at least 2 to 3 million Lyme antibody tests are performed in the United States and in Europe. This enormous and increasing request for diagnostic tests causes serious problems because the currently used techniques have a number of limitations, such as lack of diagnostic specificity and sensitivity, resulting in both over- and underdiagnosis of this condition. This article reviews the laboratory methods available to confirm the clinical diagnosis of Lyme borreliosis (LB) and focuses on the practical performance and limitations of these methods for clinical use. The different approaches are summarized in Table 1. Direct methods aim to detect either the spirochete itself or components of it in clinical specimens. Indirect methods refer to assays that measure a specific immune response to B. burgdorferi. The fundamental problem for all diagnostic tests in LB is the extremely small number of spirochetes in pathologic lesions and body fluids. The B. burgdorferi cell density is so low that even the latest, extremely sensitive methods for DNA detection seem to be at the threshold of sensitivity. © 1993.