Pitfalls in cerebrospinal fluid test for the diagnosis of neurosyphilis.

Objective: To determine the usefulness of cerebrospinal fluid tests in the diagnosis of neurosyphilis.

Methods: Two hundred and seven cerebrospinal fluid-Venereal Disease Research Laboratories tests were performed at King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia between 1992 and 1997. The records of 14 cases with progressive neurological disease and reactive serum fluorescent treponemal absorbent antibodies or treponemal pallidum hemagglutination test were reviewed for clinical presentation, cerebrospinal fluid analysis and Venereal Disease Research Laboratories, neuro-imaging abnormalities and compatibility with the diagnosis of neurosyphilis. The diagnosis of neurosyphilis was made if the patient had reactive serum fluorescent treponemal absorbent antibodies or treponemal pallidum hemagglutination, history of progressive neurological disease and increased cerebrospinal fluid cells or protein.

Results: None of the 207 cerebrospinal fluid-Venereal Disease Research Laboratories tests were reactive. The diagnosis of neurosyphilis was made in 10 out of 14 cases with progressive neurological disease and reactive serum rapid plasma reagin, fluorescent treponemal absorbent antibodies and treponemal pallidum hemagglutination.

Conclusion: We conclude that if reactive cerebrospinal fluid-Venereal Disease Research Laboratories is required to confirm or diagnose neurosyphilis, most cases will be overlooked.