P3-S6.03 Seroreversion of treponemal tests in cases meeting Canadian surveillance criteria for confirmed congenital syphilis
Bibliographic record
Abstract
Background Serologic tests for syphilis remain the mainstay of diagnosis. However, diagnosis of congenital syphilis is complicated by the passive transfer of maternal antibodies to the infant. Non treponemal test (NTT) titres should decline by age 3 months and should be non reactive by age 6 months if the infant was not infected or was infected but adequately treated. Limited data exist on the serologic outcome of treponemal tests (TT) in cases with clinical or laboratory evidence of congenital syphilis at birth. Methods Cases meeting Canadian surveillance criteria for confirmed early congenital syphilis [within 2 years of birth] ( http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/09vol35/35s2/Syphilis-eng.php ) were reviewed from the Alberta Health Services Edmonton zone from 2005 to 2010. Under Alberta's Public Health Act, maternal stage, treatment information and serologic follow-up and infant clinical, laboratory and treatment information are obtained and stored in a provincial STI database. Results 22 cases met surveillance criteria for confirmed congenital syphilis: six were either stillborn/deceased at birth, three are still under 18 month serologic follow-up, one had persistently reactive TT (21 months) and four had reactive TT at the end of their follow-up period (ages 11, 12, 13 and 15 months). 3/5 cases with persistently reactive TT were treated with 9–10 days of intravenous penicillin within 0–2 days of birth, 1 at 3 months of age and 1 at 8 months of age. In 4/5 of these cases, the RPR had reverted to non reactive at the end of the follow-up period while in the 5th case (treated at 8 months), the RPR declined from a titre of 1:4096 dilutions at birth to 1:64 dilutions at 11 months of age. The remaining eight cases had negative TTs, as summarised in the table. All were treated with 10 days of intravenous penicillin (except case #2 treated with 9 days) see Abstract P3-S6.03 table 1. Abstract P3-S6.03 Table 1 Seroreversion TT Congenital Syphillis Case* Maternal stage/GA at treatment Neonatal/infant diagnostic features Infant age at treatment (GA at birth) Infant age /final serologic results 1 Primary/postpartum Abnormal CSF (4) Birth (34 weeks) 7 months/RPR NR, TPPA NR, FTA-ABS NR 2 Primary/postpartum Abnormal CSF (3) Birth (unknown) 14 months/RPR NR, TPPA NR Abnormal long bone radiographs Intraventricular haemorrhage Fetal hydrops 3 Primary/postpartum Abnormal CSF (3) Birth (38 weeks) 10 months/syphilis EIA negative 4 Early latent/postpartum Abnormal CSF (3) Birth (30 weeks) 5 months/syphilis EIA negative 5 Early latent/34 weeks GA Abnormal CSF (3) Abnormal long bone radiographs Birth (37 weeks) 12 mos/syphilis EIA negative 6 Primary/postpartum Abnormal CSF (3) Birth (38 weeks) 18 months/syphilis EIA negative 7 Early latent/postpartum Abnormal CSF (4) Birth (36 weeks) 19 months/syphilis EIA negative 8 Secondary/28 weeks GA Abnormal CSF (4) Intrauterine anaemia, hydrops, cardiomegaly, ascites. Positive syphilis PCR from intrauterine fetal blood Birth (36 weeks) 13 months/syphilis EIA negative CSF, cerebrospinal fluid; GA, gestational age; NR, non reactive; R, reactive; EIA, enzyme immunoassay; RPR, rapid plasma reagin; TPPA, Treponema pallidum particle agglutination; FTA-ABS, fluorescent treponemal antibody absorbed; PCR, polymerase chain reaction. * Number of CSF abnormalities (elevated WBC, RBC or protein, low glucose, reactive VDRL). Conclusions As with early treatment of primary syphilis cases, seroreversion of TT can occur in cases meeting clinical and laboratory criteria for congenital syphilis. Seroreversion was observed with older TT such as TPPA and FTA-ABS as well as the newer syphilis EIA.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".