Diagnostics of early forms of syphilis by the chemiluminescence immunoassay method

Goal. Assessment of the diagnostic efficacy of the chemiluminescence immunoassay (CLIA) method for early forms of acquired syphilis. Materials and methods. The authors examined 237 blood serum samples taken from patients suffering from primary (49), secondary (116) and latent early (72) syphilis as well as from 61 healthy blood donors and 20 persons with false-positive results of serological tests for syphilis. Blood serum samples were tested with the use of CLIA, EIA, passive hemagglutination test, immunofluorescence test and microprecipitation test methods. Results. The authors established that the CLIA method used for diagnostics of early forms of acquired syphilis (when the IMMULITE® 2000 Syphilis Screen test system is used) is characterized by high sensitivity (99.6%), specificity (95.1%), diagnostic efficacy (98.3%), predictive value of positive (95.1%) and negative (98.3%) results, which is sufficient for recommending this method as the screening method for diagnostics of syphilis to be used in large diagnostic centers. The CLIA method may also be used to confirm the diagnosis of syphilis. Conclusion. Based on these results, the authors developed a reverse algorithm for diagnostics of early forms of acquired syphilis beginning with the use of the CLIA method with further use of the nontreponemal method (microprecipitation reaction or other nontreponemal method).