Asymptomatic or early syphilis
Asymptomatic syphilis, has no clinical manifestations but is defined by the presence of abnormalities in the cerebrospinal fluid in the absence of other findings of neurologic disease. The usual abnormalities include 10-100 WBC/mm3 (nearly all of which are lymphocytes), a protein of 50-100mg/dl and in, 90% of cases, a reactive nontreponemal antibody test in the cerebral spinal fluid. Blood serology (VDRL or rapid plasma reagin (RPR) is usually but not invariable positive.
The likelihood of finding cerebrospinal fluid abnormalities in persons with untreated syphilis increases until 12-18 months after initial infection, and the likelihood that neurosyphilis will develop increases in proportion to the extent of the abnormalities. Conversely, a completely normal CSF examination after 2 years of latent untreated syphilis affords reasonable assurance that neurosyphilis will not develop. Thus, because asymptomatic neurosyphilis trends, in the absence of therapy, to resolve or to progress, its frequency tends to decrease with the passage of time. In the absence of treatment, 87% of persons who had persistent CSF abnormalities for 5 years after infection went on to develop neurosyphilis.