title: Treponema pallidum western blot: comparison with the FTA-ABS test as a confirmatory test for syphilis.
abstract: We developed a Treponema pallidum Western blot and compared the results with Treponema pallidum particle agglutination (TPPA) and fluorescent treponemal antibody absorption (FTA-ABS) tests. The Western blot was deemed reactive if the serum reacted with at least three major antigenic bands (TpN47, TpN44.5, TpN17, TpN15). The sensitivities of the Western blot, TPPA and FTA-ABS, were all 100% and the specificities of the Western blot, TPPA and FTA-ABS were 100%, 100% and 94.5% respectively. In 52 problem sera, reactive in only one treponemal test, the agreement between the Western blot and TPPA (61.5%) was significantly better than between Western blot and FTA-ABS (38.5%). The individual sensitivities and specificities of TpN47, TpN44.5, TpN17, TpN15 were 100%, 100%, 96%, 100% and 20%, 96%, 100%, 100% respectively. We conclude that the Western blot is a useful additional confirmatory test or alternative to the FTA-ABS and that a more sensitive and specific criterion for the Western blot would be reactivity with TpN15 and two of the three other major antigens.
authors.affiliation: Centre for Infectious Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research (ICPMR), NSW 2145, Westmead, Australia. job@icpmr.wsahs.nsw.gov.au
authors.forename: J L
authors.initials: JL
authors.lastname: Backhouse
authors.forename: S I
authors.initials: SI
authors.lastname: Nesteroff
mesh_terms: D000372:Agglutination Tests / Q000379:methods; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000097:blood / Q000276:immunology; D015153:Blotting, Western / Q000379:methods*; D016508:Fluorescent Treponemal Antibody-Absorption Test / Q000379:methods; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D012680:Sensitivity and Specificity; D013587:Syphilis / Q000175:diagnosis*; D013588:Syphilis Serodiagnosis; D014210:Treponema pallidum / Q000276:immunology*; D014211:Treponemal Infections / Q000175:diagnosis
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M