Lissauer form of paretic neurosyphilis with a cerebral mass lesion.

A 40-year-old male patient with progressive dementia presented adversive seizures, and CT scan showed an enlarging focal mass lesion in the right cerebral hemisphere. Cerebrospinal fluid examination and brain biopsy confirmed the diagnosis of neurosyphilis. After a course of penicillin therapy there was disappearance of the cerebral mass lesion and the CT scan showed focal atrophy in the right cerebral hemisphere. This case suggests that Lissauer form of paretic neurosyphilis may present as a focal mass lesion.