Test Details
Methodology
Charcoal flocculation and immunoassay
Result Turnaround Time
1 - 2 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
This test can be used to screen individuals who are eligible for or who are receiving pre-exposure prophylaxis for HIV (PrEP) for syphilis infection. This test aligns with the CDC-supported traditional serologic testing algorithm for syphilis using a combination of both treponemal and nontreponemal antibody tests. The traditional syphilis testing algorithm begins with the RPR (nontreponemal) test with positive samples reflexing to RPR titer and treponemal antibody testing. Interpretation of results obtained must take into account patient symptoms and clinical history.
Special Instructions
PrEP use only. Contains CPT code modifier for CARES Act.
Reactive samples reflex to RPR Titer and Treponemal Antibody testing at an additional charge.
Limitations
Biological false positive results (RPR-reactive, treponemal antibody-negative) have been associated with infections other than syphilis, as well as recent immunization, autoimmune disorders, pregnancy and injection drug use.
Custom Additional Information
RPR | RPR titer | Treponemal Ab (TPAb) | Interpretation |
|---|---|---|---|
Nonreactive | Not performed | Not performed | No laboratory evidence of syphilis. If recent exposure is suspected, submit a new sample for testing in 2-4 weeks. |
Reactive | 1:1 or higher | Nonreactive | Nontreponemal antibodies detected. Syphilis unlikely; biological false positive possible. Clinical evaluation should be performed to identify current signs and symptoms or past history of infection or treatment. If recent exposure is suspected, submit a new sample for testing in 2-4 weeks. |
Reactive | 1:1 or higher | Reactive | Treponemal and nontreponemal antibodies detected. Consistent with past or current (potentially early) syphilis. Clinical evaluation should be performed to identify current signs and symptoms or past history of infection or treatment. |
Specimen Requirements
Specimen
Serum
Volume
2 mL
Minimum Volume
1 mL (Note: This volume does not allow for repeat testing.)
Container
Red-top tube or gel-barrier tube
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 14 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Storage Instructions
Room temperature
Causes for Rejection
Hemolysis; lipemia; gross bacterial contamination; plasma specimen
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 006403 | PrEP: RPR w/Reflex Titer+TPAb | 20507-0 | 006072 | RPR | 20507-0 | |
| Order Code | 006403 | |||||
| Order Code Name | PrEP: RPR w/Reflex Titer+TPAb | |||||
| Order Loinc | 20507-0 | |||||
| Result Code | 006072 | |||||
| Result Code Name | RPR | |||||
| UofM | ||||||
| Result LOINC | 20507-0 |
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 006464 | RPR, Quant. | 006464 | RPR, Quant. | titer | 31147-2 |
| Reflex 1 | ||||||
| Order Code | 006464 | |||||
| Order Name | RPR, Quant. | |||||
| Result Code | 006464 | |||||
| Result Name | RPR, Quant. | |||||
| UofM | titer | |||||
| Result LOINC | 31147-2 | |||||
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 006404 | PrEP: RPR Qn+TP Abs | 006464 | RPR, Quant. | titer | 31147-2 |
| Reflex 1 | ||||||
| Order Code | 006404 | |||||
| Order Name | PrEP: RPR Qn+TP Abs | |||||
| Result Code | 006464 | |||||
| Result Name | RPR, Quant. | |||||
| UofM | titer | |||||
| Result LOINC | 31147-2 | |||||
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 006404 | PrEP: RPR Qn+TP Abs | 082371 | Treponema pallidum Antibodies | 47236-5 | |
| Reflex 1 | ||||||
| Order Code | 006404 | |||||
| Order Name | PrEP: RPR Qn+TP Abs | |||||
| Result Code | 082371 | |||||
| Result Name | Treponema pallidum Antibodies | |||||
| UofM | ||||||
| Result LOINC | 47236-5 | |||||
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 006404 | PrEP: RPR Qn+TP Abs | 010002 | Interpretation: | 93479-4 | |
| Reflex 1 | ||||||
| Order Code | 006404 | |||||
| Order Name | PrEP: RPR Qn+TP Abs | |||||
| Result Code | 010002 | |||||
| Result Name | Interpretation: | |||||
| UofM | ||||||
| Result LOINC | 93479-4 | |||||