Prospective comparison of the Gen-probe PACE 2 Assay and the Abbott Ligase Chain Reaction for the direct detection of Chlamydia trachomatis in a low prevalence population

In a prospective study, the Gen-Probe PACE 2 (GP) assay was compared with Abbott Laboratories’ ligase chain reaction (LCR) assay for the detection of Chlamydia trachomatis. A total of 493 female patients consented to collection of two cervical samples; a first-void urine (FVU) sample was collected also from 446 of the participants. Cervical samples were tested by both GP and LCR; 16 samples (3.1%) tested positive by both methods and no discrepant results were observed. All but one of the FVU samples collected from patients with a positive cervical sample was positive for C. trachomatis by LCR. The stability of FVU samples over time in the LCR test was also evaluated and proved to be significantly longer than the 4 days stated by the manufacturer. While LCR proved to be highly sensitive in detecting chlamydial infection in FVU samples, no difference was noted between LCR and GP in the detection of cervical C. trachomatis infection in this study population.