De novo status epilepticus as the presenting sign of neurosyphilis.

Although the incidence of seizures in neurosyphilis ranges from 14 to 60%, status epilepticus (SE) as a presenting complaint of neurosyphilis is definitely rare. A 44-year-old human immunodeficiency virus (HIV)-negative man with no history of epilepsy suddenly presented with acute mental confusion and was diagnosed as having a de novo complex partial nonconvulsive SE. Cerebrospinal fluid (CSF) findings, neuroimaging, and clinical course indicated that SE was the presenting symptom of an undiagnosed syphilitic meningovasculitis. The case is presented with a review of previous reports to emphasize the differential features and to underscore the importance of considering neurosyphilis among the possible causes of de novo SE.