Clinical and laboratory features of the neurosyphilis patients enrolled in this study.

Data are given as median (range), or frequencies.
a“Duration of asymptomatic neurosyphilis” means the period between the patient's high risk behaviors which may be infected with T. pallidum and the confirmed neurosyphilis. “Duration of symptomatic neurosyphilis” means the duration of clinical manifestations;
bincludes 16 subjects with secondary syphilis, 2 subjects with early latent and 22 subjects with latent or unknown duration.