IMPROVED PERFORMANCE OF PACE-2 WITH MODIFIED COLLECTION SYSTEM IN COMBINATION WITH PROBE COMPETITION ASSAY FOR DETECTION OF CHLAMYDIA-TRACHOMATIS IN URETHRAL SPECIMENS FROM MALES

The Gen-Probe PACE 2 assay (GP) id combination with a modified collect ion system was compared with cell culture (CC) for the detection of Ch lamydia trachomatis in urethral specimens from males. Analysis of disc ordant results was performed by PCR. The modifications, i.e., applicat ion of a more rigid swab type and a 50% reduction in the amount of tra nsport medium, were made to improve the sensitivity of the assay. By u sing the modified GP on 302 urethral specimens from males, a sensitivi ty of 89.5% and a specificity of 100% were determined. In addition, pe rformance of a probe competition assay on all GP samples with a result >0.6 and <1.0 times the cutoff factor (gray zone) detected three more true-positive samples. The sensitivity of GP in combination with the probe competition assay increased to 94.9%, with a specificity of 100% . This was identical to the performance of CC. The modified GP offers a very sensitive and specific alternative to CC.