DETECTION OF CHLAMYDIA-TRACHOMATIS BY THE GEN-PROBE AMPLIFIED CHLAMYDIA-TRACHOMATIS ASSAY (AMP CT) IN URINE SPECIMENS FROM MEN AND WOMEN AND ENDOCERVICAL SPECIMENS FROM WOMEN

Molecular biology-based amplification methods are significantly more s ensitive than other methods for the detection of Chlamydia trachomatis . The performance characteristics of the new Gen-Probe AMPLIFIED Chlam ydia Trachomatis Assay (AMP CT) with endocervical and urine specimens were compared to those of culture for patients attending two Baltimore City sexually transmitted disease clinics and a clinic for adolescent s. AMP CT uses transcription-mediated amplification (TMA) and hybridiz ation protection assay procedures to qualitatively detect C. trachomat is by targeting a 23S rRNA. Discrepant results between culture-negativ e and AMP CT-positive specimens were resolved by direct fluorescent-an tibody staining of sedimented culture transport medium for elementary bodies and by TMA with 16S rRNA as a target. Following discrepant anal ysis, for 480 female urine specimens AMP CT had a sensitivity of 93.8% and a specificity of 100%. For 464 male urine specimens, the resolved sensitivity and specificity of AMP CT were 95.6 and 98.7%, respective ly. For the 479 endocervical swab specimens the sensitivity of AMP CT was 100% and the specificity was 99.5%, Resolved culture sensitivities of AMP CT for female and male swab specimens were 52.3 and 58.9%, res pectively. These results demonstrate that AMP CT is highly sensitive f or the detection of C. trachomatis in endocervical specimens and in ur ine specimens from men and women.