[Detection of anti-Treponema pallidum antibodies with colloidal gold immunoprobes].

BACKGROUND: The aim of this study was to evaluate the usefulness of colloidal gold probes widely used in histochemistry and electronic microscopy for the serologic diagnosis of syphilis. METHODS: One hundred eighty-nine sera which had been submitted to the traditional fluorescent trigenemic absorption (FTA-ABS) test and had later been tested with the new colloidal gold probe method (IAT-ABS). RESULTS: Out of a total of 103 positive samples by FTA-ABS all were positive when tested by gold immunoprobes (sensitivity 100%). Eighty-six samples which were negative by immunofluorescence were all negative by IAT-ABS (specificity 100%). CONCLUSIONS: The new method of colloidal gold probes with the current microscopy is useful for confirming serologic diagnosis of syphilis.