Diagnostics of Chlamydia Trachomatis and Nieserria Gonorrhoeae with Aptima Combo 2 Testing of Self-collecting Vaginal Samples Using Flocked Swabs and an ESwab Collection and Transport System
A significant number of infections with C. trachomatis (CT), and N. gonorrhoeae (GC) are asymptomatic, requiring screening with less invasive sampling. Flocked swabs (FS) and a universal transport media from Copan have been shown to enhance the analytical sensitivity endpoints for detection of CT and GC in contrived specimens using nucleic acid amplification assays. The current studies compared swab types and media transport systems for self-collected vaginal swabs to diagnose CT and GC in a transient youth population.
Following testing of contrived specimens prepared in ESwab Media (ESM) and PBS to determine analytical sensitivity, a total of 291 women self-collected 3 vaginal swabs in a randomized fashion; an APTIMA swab (AS) into APTIMA buffer, a flocked swab (FS) into APTIMA Combo 2 (AC@) assay (Gen-Probe). A patient was considered positive for CT or GC if at least 2 of 3 swabs were positive for an infection.
Results: CT and GC laboratory strains s ten-fold dilutions in PBS or ESM (contrived samples) revealed equal analytical sensitivity endpoints, or were within a ten-fold difference for each organism. In the clinical trial the prevalences of nfection were 12.7% (37/291) for CT, 3.1% (9/291) for GC, and 2.4% (7/291) for CT and GC together. All CT and GC infections were detected equally by the 3 sampling and transport systems, with 100% sensitivity and specificity. The majority of patients found it easy to self-collect 3 vaginal swabs.
Conclusions: Women can easily collect their own vaginal sample. Compared to the AC2 collection and transportation system, flocked swabs in APTIMA buffer and flocked ESwabs in ESM detected all of the patients infected with CT and/or GC. Flocked swabs placed into APTIMA buffer or the ESwab collection kit could be used for the diagnosis of CT or GC using the AC2 assay.