Evaluation of the Hybrid Capture 2 CT/GC DNA tests and the GenProbe PACE 2 tests from the same male urethral swab specimens.

Background: A previous study demonstrated that Digene's Hybrid Capture 2 (HC2) DNA tests for detection of Chlamydia trachomatis and Neisseria gonorrhoeae (CT/GC) could be performed using cervical swab specimens collected in GenProbe transport media with significantly greater sensitivity for the detection of C trachomatis than with the GenProbe PACE 2 system. Goal: The goal was to assess the performance of HC2 tests in comparison with GenProbe PACE 2 tests for the detection of CT/GC in male urethral swab specimens. Study Design: A total of 1202 male urethral swab specimens were collected in GenProbe PACE transport medium. All specimens were first tested with the PACE 2 system, followed by masked HC2 CT/GC testing. The GenProbe AMPLIFIED CT Assay (AMP CT) and PCR/SHARP Signal System (SHARP) were used for adjudication of discrepant results. Results: The prevalence rates for this population were 8.4% for C trachomatis and 14.6% for N gonorrhoeae, based on the adjudicated results. The relative sensitivity and specificity for the detection of C trachomatis were 97.0% and 99.8% for HC2 and 69.3% and 98.3% for PACE 2, respectively. The relative sensitivities for the detection of N gonorrhoeae were 98.9% for HC2 and 99.4% for PACE 2, with the same specificity of 99.9% for both tests. Agreement between the two testing methods was 95.4% for C trachomatis and 99.6% for N gonorrhoeae. Conclusion: The HC2 test is compatible with the GenProbe collection medium, with significantly greater sensitivity than the GenProbe PACE 2 test for detecting C trachomatis and similar sensitivities for detecting N gonorrhoeae.