Separate serum from cells within 2 hours of collection. Transfer serum from plain red tubes to an Inpeco aliquot tube.
Minimum Volumes
1.0 mL
Other Acceptable Specimens
Red (plain), red/grey SST
Storage/Transport Temperature
Refrigerated
Stability (from collection to initiation)
Refrigerated: 7 days; Frozen: 30 days
Performed
Mon-Fri
Reported
24 hours
Remarks
Positive and equivocal test results will reflex to a non-treponemal antibody test (RPR with reflex to titer).
Performing Lab
Methodist Hospital
Reference Interval
Non Reactive
Interpretive Data
T. pallidum Antibody
RPR
TPPA
Interpretation
Negative
Negative
NA
Negative - No serological evidence of syphilis.
Positive
Positive
NA
Syphilis - current or past – If there is a history of past treated syphilis, RPR titers are important in interpreting whether it has been adequately treated. If syphilis has never been treated, treat.
Positive
Negative
Negative
Negative – syphilis screen is likely a false positive. No definitive evidence of syphilis. If there is high clinical suspicion, recommend retesting in 2 weeks.
Positive
Negative
Positive
If there is a history of past treated syphilis this indicates adequately treated syphilis and no treatment is needed.
If there is no past history of syphilis this could indicate early primary syphilis or late syphilis. Treat as late syphilis unless prior testing was less than 12 months ago. If primary syphilis is suspected, repeat testing in 2 weeks.
Specimens reactive for TRPAB will be sent to an outside reference lab for RPRRR (CPT 86592). If RPRRR is non-reactive TRPA (CPT 86780) will be ordered. If RPRRR is reactive an RPR titer will be completed (CPT 86593).
Collection
Alias
Epic: EP2069
Collect
Gold (SST) tube
Specimen Preparation
Separate serum from cells within 2 hours of collection. Transfer serum from plain red tubes to an Inpeco aliquot tube.
Minimum Volumes
1.0 mL
Other Acceptable Specimens
Red (plain), red/grey SST
Storage/Transport Temperature
Refrigerated
Stability (from collection to initiation)
Refrigerated: 7 days; Frozen: 30 days
Performed
Mon-Fri
Reported
24 hours
Remarks
Positive and equivocal test results will reflex to a non-treponemal antibody test (RPR with reflex to titer).
Performing Lab
Methodist Hospital
Result Interpretation
Reference Interval
Non Reactive
Interpretive Data
T. pallidum Antibody
RPR
TPPA
Interpretation
Negative
Negative
NA
Negative - No serological evidence of syphilis.
Positive
Positive
NA
Syphilis - current or past – If there is a history of past treated syphilis, RPR titers are important in interpreting whether it has been adequately treated. If syphilis has never been treated, treat.
Positive
Negative
Negative
Negative – syphilis screen is likely a false positive. No definitive evidence of syphilis. If there is high clinical suspicion, recommend retesting in 2 weeks.
Positive
Negative
Positive
If there is a history of past treated syphilis this indicates adequately treated syphilis and no treatment is needed.
If there is no past history of syphilis this could indicate early primary syphilis or late syphilis. Treat as late syphilis unless prior testing was less than 12 months ago. If primary syphilis is suspected, repeat testing in 2 weeks.
Specimens reactive for TRPAB will be sent to an outside reference lab for RPRRR (CPT 86592). If RPRRR is non-reactive TRPA (CPT 86780) will be ordered. If RPRRR is reactive an RPR titer will be completed (CPT 86593).
