VDRL - Provincial
Discipline
Microbiology
Overview
Description
- VDRL is a non-treponemal test performed on cerebrospinal fluid to aid in the diagnosis of neurosyphilis. Neurosyphilis refers to infection of the central nervous system by Treponema pallidum and can occur at any stage of syphilis.
Ordering Recommendations
- Individuals with positive syphilis serology exhibiting signs or symptoms of neurologic involvement
- Collect CSF before antibiotic treatment is administered
Specimen Information
Specimen types accepted
- Cerebrospinal fluid
Specimen collection container
- White capped sterile conical tube
- CSF collection kit
- Black capped sterile round bottom tube
Collection procedure
- Lumbar puncture
- VDRL should not be performed on the first drawn tube of CSF or on any noticeably blood-tinged or clotted sample
Required volume
- 1 mL
Transport and stability
- Store and transport at approximately 4°C
Testing Information
Relevant clinical history
- VDRL will only be tested on individuals with positive syphilis serology
Performance
Methodology
- Reactive results will be reported with a semi-quantitative titer
- Reactive VDRL in CSF is consistent with neurosyphilis, however non-reactive VDRL in CSF does not rule out neurosyphilis. Sensitivity is estimated to be ~50%.
- Blood-tinged samples may be falsely positive when serum RPR titers are high
Days/times performed
Availability
- All specimens will be tested at RRPL
Maximum laboratory time
Result reporting
- Turnaround time of 24-48 hours from receipt in lab
Specimen retention time
- Specimens are retained for 7 days after initial processing
Other information
Additional resources
- Additional information can be found in the Saskatchewan Communicable Disease Manual
Any additional comments
- Syphilis is a Notifiable Disease. All positive test results will be sent to local Public Health officials.
Last Updated: April 17, 2024