Evaluation of patient-administered tampon specimens for Chlamydia trachomatis and Neisseria gonorrhoeae

Background: The patient-administered tampon specimen has proven to be an ea sy and sensitive method for the diagnosis of genital Chlamydia trachomatis and Neisseria gonorrhoeae infections in women by polymerase chain reaction (PCR), This method avoids the need for endocervical sampling and stringent criteria for transport. Goal: To evaluate two commercial amplification systems for the detection of C trachomatis and N gonorrhoeae from tampon specimens. Study Design: A group of 400 positive and negative tampon specimens tested by an in-house PCR method were selected from a pool of more than 2000 previ ously collected tampons. Overall, 93 C trachomatis-positive and 77 N gonorr hoeae-positive specimens were evaluated. Each specimen was tested by Roche Cobas Amplicor and Abbott LCx (LCR), and results were compared to the in-ho use PCR method, Results: Detection of C trachomatis by both assays was not significantly di fferent from the in-house PCR assay. Fewer tampons were positive for N gono rrhoeae by LCR than either the in-house assay (P = 0.0001) or by Roche Ampl icor (P = 0.01). However, tampon specimens tested by Roche Amplicor require d DNA extraction to achieve comparative sensitivity. Conclusion: Both commercial assays can be applied to tampon-collected speci mens for automated detection of sexually transmitted diseases. The detectio n of C trachomatis was similar to the in-house PCR test for both assays (P = 0.73, 0.68). Detection of N gonorrhoeae resulted in fewer positive tampon specimens when tested by ligase chain reaction than both Roche Amplicor an d in-house PCR.