Comparative Clinical Evaluation of the Alinity m STI Multiplex PCR Assay for Diagnosis and Surveillance of Chlamydia trachomatis, Neisseria gonorrhea, Trichomonas vaginalis, and Mycoplasma genitalium

BackgroundChlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are routinely tested and reported; however, Trichomonas vaginalis (TV) is the most common STI in the US and the prevalence of Mycoplasma genitalium (MG) infections is likely higher than estimated. We examined the clinical performance of the Alinity m STI assay for detection and surveillance of CT/NG/TV/MG in urine specimens from patients at a large academic medical center. MethodsPrevalence of mono- and co-infections on Alinity m STI pathogens and predictors of a positive result were identified. Alinity m STI and Aptima Combo 2 CT/NG and TV assay (Panther System) results were compared, with discrepant results run on the cobas 6800 CT/NG, TV and MG assays. Analyzer turnaround times (TAT) were determined for Alinity m and Panther systems. Results199 urine specimens were included. Age [≥]25 years, collection outside the emergency department (ED), and asymptomatic status were predictive of TV or MG infection; symptomatic status was the only predictor of CT or NG infection. Overall agreement rates for the Alinity m, Aptima, and cobas assays ranged from 86.4% to 99.5% for the four pathogens. TV and MG infections comprised 54% of the positive samples and were more often asymptomatic than CT and NG infections. Analyzer TAT (onboard to result reporting) was 4 hours 45 minutes for the Aptima CT/NG, 3 hours 25 minutes for Aptima TV, and 1 hour 55 minutes for Alinity m STI assay. ConclusionsThe Alinity m STI assay allows for fast and simultaneous detection of the four major STI pathogens, which can facilitate surveillance and provide accurate results to help clinicians diagnose for initiation of appropriate treatment.