RPR, Serum (Syphilis Serology)

Tube Type

Test ID   LAB494
EPIC Order
CPT Code(s)   86592, (86593 if positive)
Group/Individual Test   Group
Laboratory   Clinical Immunology
Tube Station   30
Specimen Routine: 2 ml blood/Serum Separator Tube/Gold Top
Availability Routine: Monday-Friday
  STAT: Stat requests require phone call to lab: 984-974-1815 (Mon-Sat, 8am-4pm); 984-974-1805 (after hours)
Turnaround Time   1-3 Days (Routine); 1-2 Hours (STAT)
Reference Range Normal: Non-Reactive;  See Important Comments.

The Rapid Plasma Reagin (RPR) test is a nontreponemal test detecting antibodies (reagin) reacting with the cardiolipin-lecithin-cholesterol antigen.    The RPR is performed with undiluted serum.  Results are reported as non-reactive or reactive.   Reactive samples are serially diluted and retested to determine the endpoint titer that is reported with the reactive result.  Reactive results are reflexed to TP-PA confirmation if the patient has not been previously confirmed.  TP-PA reflex is not conducted on patients that have a documented previously positive treponemal test result. 

RPR titers can decline with time during late syphilis.  Additionally, titers can be used to monitor the response to therapy.  The RPR is not to be used for testing CSF.   The CSF VDRL test is offered for detection of non-treponemal antibodies in CSF.

Reviewed by jcarr on November 30, 2021

Note: Reference ranges provided on this web site are for guidance only, and may not reflect the most recent changes. Refer to laboratory reports for current reference data.

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514