TABLE 1

Comparator assays, confirmation methods, Elecsys syphilis assay reagent lots, and samples tested at each of the laboratories

LaboratoryComparator assay(s) usedConfirmation method(s) usedElecsys syphilis assay reagent lots and samples
Laboratory Enders, Stuttgart, GermanyLIAISON Treponema screen; Serodia-TPPA (routinely used at this center)aFTA-ABS-IFA test system IgG, IgM (Zeus Scientific); Treponema+VDRL ViraBlot IgG, IgM (Viramed); recomLine Treponema IgG/IgM (Mikrogen); Oxoid VDRL (Fisher Scientific)a,bLot A: 1,500 routine plasma samples predominantly from antenatal care, 242 positive samples with defined clinical stage (from ZeptoMetrix), 60 confirmed-positive plasma samples with defined clinical stage
Labor Schottdorf, Augsburg, GermanyArchitect syphilis TP; LIAISON Treponema screen (routinely used at this center); Immulite 2000 syphilis screencFTA-ABS-IFA test system IgG, IgM (Zeus Scientific); TPHA (Lab21); VDRL cardiolipin antigen (Siemens)a,d,eLots B and C: 1,000 routine serum samples predominantly from antenatal care; lot A: 1,500 routine serum samples predominantly from antenatal care, 83 confirmed-positive serum samples, 10 samples positive for Epstein-Barr virus, and 10 positive for Lyme disease (potentially cross-reactive)
Central Institute for Blood Transfusion and Immunology, Innsbruck, AustriaArchitect syphilis TP; Enzygnost syphilis (routinely used at this center)cSerodia-TPPA (Fujirebio); recomBlot Treponema IgG/IgM (Mikrogen); recomLine Treponema IgG/IgM (Mikrogen); RPR reditest (Biokit)eLots B and C: 1,049 serum blood donation samples; lot A: 1,506 serum blood donation samples
National Blood Center, Bangkok, ThailandArchitect syphilis TPAlere Determine syphilis TP (Immunochromatographic strip test); RPR (Lab21); TPHA 2000 (Lab21); Virotech T. pallidum LINE IgM immunoblot (Sekisui); Treponema ViraBlot IgG (Viramed); VDRL cardiolipin antigen (Siemens); recomLine Treponema IgG/IgM (Mikrogen)f,gLot A: 1,500 serum blood donation samples, 124 confirmed-positive samples
Ege University, Izmir, TurkeyArchitect syphilis TPcTPHA (Randox Laboratories); FTA-ABS IgG, IgM (Euroimmun); EUROLINE-WB T. pallidum IgG, IgM (Euroimmun); RPR card test (Omega Diagnostics)hLots B and C: 632 plasma blood donation samples
MUC Research GmbH, Munich, GermanyImmulite 2000 syphilis screenTPHA 2000 (Lab21); Virotech T. pallidum LINE IgM immunoblot (Sekisui); Treponema ViraBlot IgG (Viramed); recomLine Treponema IgG/IgM (Mikrogen); VDRL cardiolipin antigen (Siemens)f,gLot A: 225 syphilis-negative plasma samples from patients with confirmed HIV infection, 228 syphilis-positive plasma samples from patients with confirmed HIV coinfection
West China Hospital, Chengdu, ChinaTRUST (Rongsheng Biotech); ELISA kit for TP (InTec [Xiamen]); Serodia-TPPA (Fujirebio)iLot A: 202 confirmed-positive plasma samples with defined clinical stage
Hub Laboratory of the Greater Romagna Area, Pievesestina, ItalyLIAISON Treponema screen (for the routine requested samples); Vitros syphilis TPA (for blood donation samples); Immulite 2000 syphilis screenTPHA kit (FAR Diagnostics); recomLine Treponema IgG/IgM (Mikrogen); Immutrep-RPR (Omega Diagnostics)Lot A: 500 routine serum samples, including antenatal care, 1,574 blood donation serum samples, 218 confirmed-positive samples with defined clinical stage, 81 serum samples positive for Epstein-Barr virus (potentially cross-reactive)
  • a The Serodia-TPPA, FTA-ABS-IFA test system IgG, IgM, Oxoid VDRL, Treponema+VDRL Virablot IgG, IgM, and recomLine Treponema IgG/IgM assays in Stuttgart, as well as the FTA-ABS-IFA test system IgG, IgM and VDRL cardiolipin antigen assays at Augsburg, were used to confirm the samples sent from the laboratory in Bangkok.

  • b The FTA-ABS-IFA test system IgG, IgM and recomLine Treponema IgG/IgM assays in Stuttgart were also used to confirm the samples sent from the laboratory in Innsbruck.

  • c The comparators used for lot B and C testing were the LIAISON Treponema screen at Augsburg, the Enzygnost syphilis assay at Innsbruck, and the Architect syphilis TP assay at Izmir.

  • d The VDRL cardiolipin antigen and FTA-ABS-IFA test system IgG, IgM assays in Augsburg were also used to confirm the samples sent from the laboratory in Munich and Pievesestina.

  • e The recomLine Treponema IgG/IgM assay in Innsbruck was also used to confirm the samples sent from the laboratory in Augsburg.

  • f The TPHA 2000, Virotech T. pallidum LINE IgM immunoblot, Treponema ViraBlot IgG, and VDRL cardiolipin antigen assays for samples from Bangkok and Munich were performed by Medizinische Laboratorien Düsseldorf, Düsseldorf, Germany.

  • g The recomLine Treponema IgG/IgM assays for Bangkok and Munich were performed by Roche Diagnostics, Penzberg, Germany.

  • h These assays were performed by the Düzen Laboratory, Ankara, Turkey.

  • i TRUST, syphilis toluidine red untreated serum test (cardiolipin card test); ELISA, enzyme-linked immunosorbent assay.