Evaluation of the DCL Syphilis-G enzyme immunoassay test kit for the serologic diagnosis of syphilis.

Sera have been submitted to the authors' laboratory for syphilis testing at a dramatically increased rate since the start of the human immunodeficiency virus type 1 epidemic. Thus they were interested in evaluating a new enzyme immunoassay, the DCL Syphilis-G test kit (DCL-G, Diagnostic Chemicals Ltd., Oxford, CT) for detection of immunoglobulin G antibodies to Treponema pallidum. The enzyme immunoassay format, with its potential for automation, is ideally suited for large volume batch testing. Five hundred eighty-five sera collected primarily from pediatric patients were subjected to rapid plasma reagin and DCL-G testing. The patients ranged in age from 1 day to 45 years (mean, 14.4 years). Sera yielding positive or equivocal results in duplicate by either method were tested further for T. pallidum immunoglobulin G and M antibodies by the fluorescent treponemal antibody absorbed test and the DCL Syphilis-M test kit. The sensitivity and specificity of DCL-G, considering the combined rapid plasma reagin and fluorescent treponemal antibody absorbed results as the reference, were 100% and 99.8%, respectively. It was concluded that the DCL-G assay was a simple, efficient, and accurate method for obtaining confirmed serologic evidence of past or present syphilis.