Comparison between Aptima® assays (Hologic) and the CoBAS® 6800 system (Roche) for the diagnosis of sexually transmitted infections caused by Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium

Nowadays, it is of utmost importance to use fully validated assays for molecular-based diagnosis. In the field of sexually transmitted disease (STD), Roche and Hologic provide assays for diagnosing Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), and Trichomonas vaginalis (TV). A total of 212 clinical samples were tested. Aptima (R) Combo 2 (detecting CT and NG), Aptima (R) M. genitalium and the Aptima (R) T. vaginalis on the Panther (R) system were compared to CoBAS (R) CT/NG and CoBAS (R) TV/MG running on the CoBAS (R) 6800 system. To solve the discrepancies, Allplex (TM) STI Essential assay (Seegene (R)) and/or Sanger DNA sequencing were used. The diagnostic performance was calculated by mean of the sensitivity and specificity parameters. Aptima (R) (sensitivity: 98.90%, specificity: 100%), CoBAS (R) (sensitivity 100%, specificity: 96.67%). The CoBAS (R) combo (CT/NG) failed detecting NG from an anal/rectum specimen, which is not included into the validated specimens of the assay. Aptima (R) combo 2 produced two false positives (CT and NG), not detected by the third tests. All the assays showed an optimal diagnostic capacity, meeting the requirements for IVD DNA-based assays. All products work optimally on automatic platforms, minimizing time and risk of contamination during handling.

Automated summary

It is crucial to use fully validated assays in molecular-based diagnosis, especially in the field of STD. Roche and Hologic provide effective assays for diagnosing CT, NG, MG, and TV, with different sensitivity and specificity parameters on their respective platforms. All assays demonstrated optimal diagnostic capacity to meet IVD DNA-based assay requirements.