Written by Carmen Wolfe
Neurosyphilis is on the rise – brush up on the facts now before you miss it.
The return of the spirochete
Mentally catalog these brief neurosyphilis tidbits.
When should I consider neurosyphilis?
- Now! Rates of syphilis are increasing dramatically, disproportionately affecting Native American, Alaska Native, and African American populations.
- Neurosyphilis can develop during primary, secondary, or tertiary syphilis.
What does neurosyphilis look like?
- Neurosyphilis can be asymptomatic and often resolves even with non-neurosyphilis antibiotic regimens, but a subset will persist and progress to a symptomatic stage.
- Symptomatic neurosyphilis takes various forms at differing time periods after primary infection.
- Meningeal (< 1 yr): acute meningitis, cranial nerve palsies, hydrocephalus
- Meningovascular (5-12 yrs): endarteritis/infarction in brain causing stroke or spinal cord
- Parenchymatous (15-20 yrs): memory loss, disorientation, poor judgment, progressive decline
- Tabes dorsalis (20-25 yrs): posterior column degeneration causing gait disturbances and decreased sensation
- CNS gummas (2-40 yrs): benign cerebral or spinal cord tumors causing symptoms based on location
- Ocular and otic syphilis often overlap with neurosyphilis; if you find one, look closely for the other.
How will I diagnose neurosyphilis?
- If a patient with syphilis has neurologic signs/symptoms, CSF should be obtained and sent for FTA-ABS (sensitive) and VDRL (specific).
- Imaging is only indicated to rule out other diagnoses or evaluate for hydrocephalus.
How do I treat neurosyphilis?
- Admit for penicillin G 3-4 million units IV q4hr x 10-14 days
- In reliable populations, consider outpatient care: penicillin G 2.4 million units IM daily + probenecid 500 mg PO QID for 10-14 days.
- Small studies support using ceftriaxone for anaphylactic penicillin allergies.
How will this change my practice?
Understanding that prevalence is increasing, I will be more astute in considering neurosyphilis in my differential diagnoses, aiming to identify and treat these patients to prevent disease progression and disability.
State-of-the-Art Review: Neurosyphilis. Clin Infect Dis. 2023 Aug 18;ciad437. doi: 10.1093/cid/ciad437. Online ahead of print.