Use of cerebrospinal fluid enzyme immunoassay for diagnosis of neurosyphilis.

Neurosyphilis is a difficult clinical stage of syphilis as there is no ideal method for diagnosis and workup requires lumbar puncture which may sometimes provide ambiguous results especially in HIV co-infected patients. Enzyme immunoassay is a widely used screening test for syphilis in serum, but its test performance was not well studied in cerebrospinal fluid. To examine the diagnostic performance of cerebrospinal fluid-enzyme immunoassay (CSF-EIA) in neurosyphilis, we conducted a prospective study for two years.