False-Positive Venereal Disease Research Laboratory Tests in the Cerebrospinal Fluid With Meningeal Carcinomatosis

Abstract

There are many causes of false-positive Venereal Disease Research Laboratory (VDRL) tests in serum, for example, systemic lupus erythematosus, pregnancy, liver disease, intravenous drug abuse. Such patients have a negative serum fluorescent treponemal antibody absorption test. False-positive VDRLs in the cerebrospinal fluid (CSF) are extremely rare. We present a case of suspected neurosyphilis in a patient with a negative serum VDRL and fluorescent treponemal antibody absorption test but with a positive CSF VDRL. This is only the third reported case of a false-positive CSF VDRL, which, in this case, was caused by meningeal carcinomatosis.