Useful For
Suggests clinical disorders or settings where the test may be helpful
Diagnosing syphilis
Highlights
This test is for the diagnosis of syphilis infection.
Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.
Test Id |
Reporting Name |
Available Separately |
Always Performed |
RPRT4 |
RPR, Titer, S |
No
|
No |
RTPPA |
Syphilis Ab, TP-PA, S |
Yes, (Order TPPA)
|
No |
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
If this test is positive, then the rapid plasma reagin titer will be performed at an additional charge.
If this test is negative, then the Treponema pallidum particle agglutination test will be performed at an additional charge.
For more information see Syphilis Serology Algorithm.
Method Name
A short description of the method used to perform the test
RPRT3, RPRT4: Flocculation/Agglutination
RTPPA: Particle Agglutination
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Yes
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
RPR w/ Reflex to TP-PA, S
Aliases
Lists additional common names for a test, as an aid in searching
Rapid Plasma Reagin Test (RPR)
RPRT3
Syphilis G
Syphilis Serology (RPR)
Treponema pallidum (T. pallidum)
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
If this test is positive, then the rapid plasma reagin titer will be performed at an additional charge.
If this test is negative, then the Treponema pallidum particle agglutination test will be performed at an additional charge.
For more information see Syphilis Serology Algorithm.
Specimen Type
Describes the specimen type validated for testing
Serum
Ordering Guidance
This assay should only be used following an initial reactive treponemal antibody assay result as part of the reverse syphilis testing algorithm.
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.3 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
If not ordering electronically, complete, print, and send an Infectious Disease Serology Test Request (T916) with the specimen.
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
See Specimen Required
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
Gross hemolysis Reject
Thawing Cold OK; Warm reject
Gross lipemia Reject
Specimen Type |
Temperature |
Time |
Special Container |
Serum |
Refrigerated (preferred) |
14 days |
|
|
Frozen |
14 days |
|
Useful For
Suggests clinical disorders or settings where the test may be helpful
Diagnosing syphilis
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
If this test is positive, then the rapid plasma reagin titer will be performed at an additional charge.
If this test is negative, then the Treponema pallidum particle agglutination test will be performed at an additional charge.
For more information see Syphilis Serology Algorithm.
Syphilis is caused by infection with the spirochete Treponema pallidum subspecies pallidum. The infection is systemic, and the disease is characterized by periods of latency. These features, together with the fact that T pallidum cannot be isolated in culture, mean that serologic techniques play a major role in the diagnosis and follow-up of treatment for syphilis.
Historically, the serologic testing algorithm for syphilis included an initial nontreponemal screening test, such as the rapid plasma reagin (RPR) or the VDRL tests. Because these tests measure the host's immune response to nontreponemal antigens, they lack specificity. Therefore, a positive result by RPR or VDRL requires confirmation by a treponemal-specific test, such as the fluorescent treponemal antibody-absorption (FTA-ABS) or microhemagglutination (MHA-TP) assay. Although the FTA-ABS and MHA-TP assays are technically simple to perform, they are labor intensive and require subjective interpretation by testing personnel.
As an alternative to the traditional syphilis screening algorithm, many laboratories utilize the reverse syphilis screening algorithm. This algorithm starts with an automated treponemal assay to detect antibodies specific to T pallidum. If this screening assay is positive, the sample is reflexed for testing by RPR, which, if positive, is reported with a titer and is indicative of active or recent syphilis infection. If the RPR is negative, the sample is reflexed to a second treponemal assay, such as the T pallidum particle agglutination (TP-PA) assay. If the TP-PA is positive, this would indicate previously treated or late-stage syphilis infection. Alternatively, if the TP-PA is negative, the initial positive screen is interpreted as a false positive result.
Patients with primary or secondary syphilis are typically tested by RPR to their monitor response to treatment. Typically, RPR titers decrease following successful treatment, but this may occur over a period of months to years. Additionally, testing of maternal and neonate serum, collected concurrently, by RPR can be used as an aid to diagnose congenital syphilis.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Negative
Reference values apply to all ages.
Interpretation
Provides information to assist in interpretation of the test results
Negative:
Non-treponemal antibodies not detected. Testing on a new specimen collected in 2 to 3 weeks is recommended if acute infection is suspected. Sample reflexed for detection of Treponema pallidum specific antibodies by the T pallidum particle agglutination assay.
Positive:
Specimen reflexed to determine rapid plasma reagin titer.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Biological false-positive reactions with cardiolipin-type antigens have been reported in diseases such as infectious mononucleosis, leprosy, malaria, lupus erythematosus, vaccinia, and viral pneumonia.
Pregnancy, autoimmune diseases, and narcotic addictions may give false-positive results. Pinta, yaws, bejel, and other treponemal diseases may also produce false-positive results with this test.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Tuddenham S, Katz SS, Ghanem KG. Syphilis Laboratory Guidelines: Performance characteristics of nontreponemal antibody tests. Clin Infect Dis. 2020;71(Suppl 1):S21-S42. doi:10.1093/cid/ciaa306
2. Park IU, Tran A, Pereira L, Fakile Y. Sensitivity and specificity of treponemal-specific tests for the diagnosis of syphilis. Clin Infect Dis. 2020;71(Suppl 1):S13-S20. doi:10.1093/cid/ciaa349
3. Theel ES, Katz SS, Pillay A. Molecular and direct detection tests for Treponema pallidum subspecies pallidum: A review of the literature, 1964-2017. Clin Infect Dis. 2020;71(Suppl 1):S4-S12. doi:10.1093/cid/ciaa176
4. Ortiz DA, Shukla MR, Loeffelholz MJ. The traditional or reverse algorithm for diagnosis of syphilis: Pros and cons. Clin Infect Dis. 2020;71(Suppl 1):S43-S51. doi:10.1093/cid/ciaa307
Method Description
Describes how the test is performed and provides a method-specific reference
If the rapid plasma reagin (RPR) screen is reactive, the RPR titer is performed. The RPR titer test is a macroscopic screening assay done with unheated serum. Reagin reacts with nontreponemal antigen containing colloidal charcoal particles. This reaction results in a visual flocculation of the black particles against the white card background. The test yields a positive or negative result, and all positive samples are titered to determine the highest positive dilution.(Huber TW, Storms S, Young P, et al. Reactivity of microhemagglutination, fluorescent treponemal antibody absorption, Venereal Disease Research Laboratory, and rapid plasma reagin tests in primary syphilis. J Clin Microbiol. 1983;17[3]:405-409; Kaur G, Kaur P. Syphilis testing in blood donors: an update. Blood Transfus. 2015;13[2]:197-204)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
No
Monday through Saturday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Same day/1 to 4 days
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
14 days
Rochester
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
86592
86593- (if appropriate)
86780- (if appropriate)
Test Id |
Test Order Name |
Order LOINC Value
|
RPRT3 |
RPR w/ Reflex to TP-PA, S |
20507-0 |
Result Id |
Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
616970 |
RPR w/ Reflex to TP-PA, S |
20507-0 |