DETECTION OF BORRELIA-BURGDORFERI-SPECIFIC ANTIGEN IN ANTIBODY-NEGATIVE CEREBROSPINAL-FLUID IN NEUROLOGIC LYME-DISEASE

Objective: To determine the potential of detection in CSF of specific Borrelia burgdorferi antigen, OspA, as a marker of infection in neurol ogic Lyme disease and compare this with the detection of antibody. Des ign: CSF from 83 neurologic patients in an area highly endemic for Lym e disease was examined prospectively for (1) OspA by antigen capture E LISA and Western blot employing monoclonal antibodies, and for (2) B b urgdorferi antibodies by ELISA. Results: Of the 35 of 83 (42%) patient s who were positive for OspA. antigen in their CSF, 15 (43%) were anti gen positive despite being antibody-negative in CSF. Seven of these 15 (47%) had otherwise normal routine CSF analyses. Six of these 15 (40% ) patients met strict CDC surveillance criteria for Lyme disease; four (27%) patients had seroconversion coincident with new neurologic prob lems; and three (20%) with characteristic syndromes for Lyme disease w ere seronegative, but had complexed antibody to B burgdorferi. The fin al two patients (13%) were seropositive and had unexplained neurologic problems not characteristic of Lyme disease. Conclusions: B burgdorfe ri antigen can be detected in CSF that is otherwise normal by conventi onal methodology, and can be present without positive CSF antibody. Si nce CSF antigen implies intrathecal seeding of the infection, the diag nosis of neurologic infection by B burgdorferi should not be excluded solely on the basis of normal routine CSF or negative CSF antibody ana lyses.