German guideline on neurosyphilis.

Neurosyphilis is a severe disease which can manifest with various clinical signs. The diagnosis can be challenging. Patients with positive syphilis serology and neurological or psychiatric symptoms should undergo cerebrospinal fluid (CSF) examination. The definite diagnosis is based on CSF findings, including evidence of inflammation, intrathecal production of treponemal antibodies (plus reactive non-treponema specific tests in the CSF). However, these criteria are not always fulfilled and a diagnosis of probable neurosyphilis may be established using less stringent diagnostic criteria. Treatment with intravenous penicillin or ceftriaxone is recommended for neurosyphilis. Here, a short version of the recommendations of the German guidelines on neurosyphilis that were published in 2026 is presented.