A late form of neurosyphilis manifesting with psychotic symptoms in old age and good response to ceftriaxone therapy.

Neurosyphilis can present with psychiatric symptoms. The late form can occur in old age with psychosis, paranoid delusions, affective disorders or cognitive impairment. Here we present a case of neurosyphilis in an elderly woman who, over six months, progressively manifested personality changes and paranoid delusions which were initially suspected as Alzheimer's disease. Psychotic symptoms showed a good response to antibiotic treatment. We conclude that neurosyphilis is a relevant differential diagnosis in patients developing severe psychiatric symptoms in old age. As a causal antibiotic treatment is possible this infectious disease should be considered seriously in gerontopsychiatric patients.