From the Guidelines
The earliest manifestations of neurosyphilis typically occur within weeks to months after initial syphilis infection and include asymptomatic neurosyphilis, syphilitic meningitis, and meningovascular syphilis. These manifestations can be identified through a combination of reactive serologic test results, abnormalities of cerebrospinal fluid (CSF) cell count or protein, or a reactive VDRL-CSF with or without clinical manifestations 1. The diagnosis of neurosyphilis usually depends on various combinations of these tests, as no single test can be used alone to diagnose the condition 1. Some key clinical presentations include:
- Asymptomatic neurosyphilis, where patients show no clinical symptoms but have abnormal cerebrospinal fluid findings
- Syphilitic meningitis, presenting with headache, neck stiffness, cranial nerve palsies, and occasionally seizures
- Meningovascular syphilis, manifesting as stroke-like symptoms due to inflammation of blood vessels in the brain, typically occurring 5-10 years after initial infection Other early signs may include changes in personality, confusion, and visual disturbances. Diagnosis requires cerebrospinal fluid analysis showing pleocytosis, elevated protein, and positive VDRL or FTA-ABS tests 1. Treatment for neurosyphilis consists of intravenous penicillin G (18-24 million units daily) for 10-14 days, and early recognition and treatment are crucial as these manifestations can progress to more severe forms like general paresis or tabes dorsalis if left untreated 1. The spirochete Treponema pallidum enters the central nervous system early in infection, which explains why neurological manifestations can occur even in primary or secondary stages of syphilis. It is essential to note that the VDRL-CSF is highly specific but insensitive, and most other tests are both insensitive and nonspecific, requiring interpretation in relation to other test results and clinical assessment 1.
From the Research
Earliest Manifestations of Neurosyphilis
The earliest manifestations of neurosyphilis can be grouped into two categories: early and late. The early forms include:
- Asymptomatic neurosyphilis
- Meningeal neurosyphilis
- Meningovascular neurosyphilis 2 These forms can occur within weeks to years of primary infection and primarily involve the meninges. Syndromes include syphilitic meningitis, often accompanied by cranial neuropathies, and meningovascular syphilis with associated ischemic stroke 3.
Clinical Presentation
The clinical presentation of early neurosyphilis can be diverse, including:
- Acute onset of CNS, ocular, and/or otic symptomatology
- Documented seroconverting syphilis serology or a >4-fold increase in rapid plasma reagin (RPR) test titre within the previous 12 months 4
- Syphilitic meningitis
- Meningovascular syphilis
- Asymptomatic neurosyphilis 2, 3
Diagnosis and Treatment
Diagnosis of neurosyphilis is complex and based on the study of cerebrospinal fluid (CSF) and serological tests 2, 5, 3, 6. The treatment of choice for neurosyphilis is penicillin G, although ceftriaxone may be a reasonable alternative therapy 3, 6. It is essential to have a high index of suspicion and awareness of the variable clinical presentations of neurosyphilis to approach this treatable infection effectively 6.