title: Evaluation of recomWell Treponema, a novel recombinant antigen-based enzyme-linked immunosorbent assay for the diagnosis of syphilis.
abstract: OBJECTIVE
  To evaluate the diagnostic performance of an enzyme immunosorbent assay (recomWell Treponema) for the diagnosis of syphilis. The novel recombinant antigens Tpn47, TpN17 and TpN15 were utilized.
  
  
  METHODS
  A total of 782 human serum specimens, belonging to four different categories (blood donors, n = 200; routine laboratory screening for syphilis, n = 400; syphilis patients, n = 122; potential cross-reactors, n = 60), were evaluated to compare the sensitivity and specificity of the recomWell Treponema kit with a standard whole Treponema pallidum cell lysate antigen-based ELISA (Syphilis Screening) and with micro-haemagglutination (MHA-TP).
  
  
  RESULTS
  The overall specificity and sensitivity of the recomWell Treponema IgG was 98.9% and 98.3%, respectively. The specificity and sensitivity of Syphilis Screening ELISA was 98.7% and 98.3%, respectively. The agreement between recomWell Treponema and Syphilis Screening was 100%, 97.8%, 95.9% and 95% among the blood donor specimens, screening samples, syphilis specimens and the potential cross-reactors, respectively. Values of concordance varying from 96.7% to 98.3% were found in the different groups of sera between recomWell Treponema and MHA-TP. In addition, recomWell Treponema demonstrated a good diagnostic performance when used to detect the IgM to T. pallidum. No false-positive sera were identified and, in 17/19 samples from primary infection, an IgM immune response was found.
  
  
  CONCLUSIONS
  recomWell Treponema was shown to be a highly specific and sensitive method in all stages of syphilis screening and it can be considered as alternative to other ELISA tests based on native antigen preparations.
authors: Departments of Microbiology and Dermatology, DMCSS, University of Bologna, St Orsola Hospital, via Massarenti 9, 40138 Bologna, Italy.
authors: V
authors: V
authors: Sambri
authors: A
authors: A
authors: Marangoni
authors: M A
authors: MA
authors: Simone
authors: A
authors: A
authors: D'Antuono
authors: M
authors: M
authors: Negosanti
authors: R
authors: R
authors: Cevenini
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods* / Q000592:standards; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D011933:Reagent Kits, Diagnostic; D011994:Recombinant Proteins / Q000276:immunology; D012680:Sensitivity and Specificity; D013587:Syphilis / Q000097:blood / Q000175:diagnosis*; D013588:Syphilis Serodiagnosis / Q000379:methods* / Q000592:standards; D014210:Treponema pallidum / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011933:Reagent Kits, Diagnostic; D011994:Recombinant Proteins