Efficacy of an RNA detection test kit in the diagnosis of genital chlamydial infection

A nucleic acid amplification method based on DNA detection, the current standard method for the diagnosis of genital infection by Chlamydia trachomatis, has been shown to potentially yield false-positive results after treatment in the clinical setting. RNA detection methods are more appropriate because viable organisms have multiple RNA copies that are surely detected by the method. In this study, we evaluated the efficacy of a new RNA detection test kit, the VIDAS PROBE CT test, in the diagnosis of genital chlamydial infection. For comparison, the standard DNA detection method, Amplicor STD-I, was also used in the study. First voided-urine samples and urethral smears from male patients with urethritis, and first voided-urine samples and cervical smears from female patients with cervicitis served as samples for the detection of C. trachomatis. Of the 60 first voided-urine samples from male patients, 21 were positive and 39 negative with the VIDAS PROBE CT test. Amplicor STD-I achieved exactly the same result. In female patients with cervicitis, the two test kits produced the same result, with 2 positive cervical smears and 38 negative. These results suggest that the VIDAS PROBE CT test is as efficient as Amplicor STD-I in the detection of C. trachomatis. While studies including a greater number of patients will be needed for revealing the unique advantages of the new RNA detection test kit, VIDAS PROBE CT, we concluded from the current study that the test may be clinically useful in the diagnosis of genital chlamydial infection.