The cobas CT/NG v2.0 test for Chlamydia trachomatis and Neisseria gonorrhoeae performed well when tested for sensitivity and specificity, according to results published in Sexually Transmitted Infections.
Sensitivity and specificity of the cobas test using 3 sample types (vaginal swab, endocervical swab, and urine) was estimated by comparison with infection status determined from 2 US Food and Drug Administration-cleared nucleic acid tests. Urogenital swabs, urine, and cervical cytology samples in PreservCyt solution were collected from 5266 symptomatic and asymptomatic women, 202 of whom were pregnant, as well as 738 men.
Among the 6004 participants 487 C trachomatis (8.1%) infections and 159 N gonorrhoeae (2.6%) infections were identified. The estimates of sensitivity for C trachomatis in women ranged from 91.2% to 97.6%, depending on sample type, and 95.6% to 100.0% for N gonorrhoeae. The results of urine samples collected from men yielded findings of sensitivity for C trachomatis at 98.4%, and for N gonorrhoeae at 100.0%. Specificity for C trachomatis ranged from 99.2% to 99.7%, and for N gonorrhoeae they ranged from 99.3% to 100.0%.
The cobas test performed well in this study; sensitivity, specificity, positive predictive value, and negative predictive value for all sample types were greater than 90%. The study also demonstrated the utility of the test in both asymptomatic populations and as a diagnostic for symptomatic patients. According to investigators, “availability of new assays such as the cobas CT/NG v2.0 test provides laboratories with a comprehensive approach to genital tract [C trachomatis and N gonorrhoeae] infection testing.”
Funding for this study was provided by Roche Molecular Systems, Pleasanton, CA.
Nye MB, Osiecki J, Lewinski M, et al. Detection of Chlamydia trachomatis and Neisseria gonorrhoeaewith the cobas CT/NG v2.0 test: performance compared with the BD ProbeTec CT Qx and GC Qx amplified DNA and Aptima AC2 assays [published online August 20, 2018]. Sex Transm Infect. doi: 10.1136/sextrans-2018-053545