Rapid Plasma Reagin Screen with Reflex to Titer, Serum
Use
This test aids in the diagnosis of infection with Treponema pallidum and is used for rapid plasma reagin testing following a positive treponemal antibody test. It is important in the diagnosis and follow-up of syphilis treatment. The RPR is a macro-flocculation test which, if positive, indicates the presence of nonspecific antibodies in the patient's serum suggesting active syphilis. In the context of syphilis testing, the RPR is used as part of the reverse syphilis screening algorithm to confirm the presence of infection after a positive syphilis IgG result. However, RPR is not useful as a screening or confirmatory test for blood donor specimens, due to its limited specificity in these contexts.
Special Instructions
Not provided.
Limitations
The test may produce false negatives in severely immunosuppressed patients, such as those with AIDS. Serologic tests might also be negative in very early cases of primary syphilis or untreated late or latent syphilis. Additionally, this test is nonspecific and cannot differentiate between active and past treated syphilis if using treponemal assays. The presence of antibodies can persist even after effective treatment, thus interpretation in the context of clinical and historical data is crucial for accurate diagnosis.
FDA ApprovedNew York Approved
Methodology
Other (Flocculation/Agglutination)
Biomarkers
Treponema pallidum
Microorganism
LOINC Codes
- 20507-0 - RPR Ser Ql
- 20507-0 - RPR Ser Ql
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.4 mL
Container
Plastic vial
Collection Instructions
Centrifuge and aliquot serum into a plastic vial. Use either a serum gel (preferred) or red top tube for collection.
Causes for Rejection
Gross hemolysis, gross lipemia, heat-inactivated specimen.
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 14 days |