What laboratory test supports the diagnosis of Lyme disease?

The diagnosis of Lyme disease is primarily supported through serologic antibody testing. This type of testing helps detect the presence of antibodies, specifically IgM and IgG, which the immune system produces in response to the Lyme borreliosis-causing bacterium, Borrelia burgdorferi. Typically, serologic tests are performed when a patient presents with signs and symptoms consistent with Lyme disease, such as erythema migrans or flu-like symptoms.

Antibody testing is most reliable a few weeks after the initial infection, allowing for adequate immune response, and is crucial for confirming Lyme disease when clinical signs are present or when there is a history of potential tick exposure in endemic areas.

KOH preparation of skin scrapings is primarily used for diagnosing fungal infections rather than Lyme disease. Blood cultures are not a preferred method for diagnosing Lyme disease, as Borrelia burgdorferi is difficult to culture from blood. RAST testing is mainly utilized for identifying allergies and is not related to the diagnosis of Lyme disease. Therefore, serologic antibody testing is the standard laboratory method for confirming the diagnosis of this condition.