A 30-Min Nucleic Acid Amplification Point-of-Care Test for Genital Chlamydia trachomatis Infection in Women: A Prospective, Multi-center Study of Diagnostic Accuracy

Rapid Point-Of-Care Tests for Chlamydia trachomatis (CT) may reduce onward transmission and reproductive sexual health (RSH) sequelae by reducing turnaround times between diagnosis and treatment. The io® single module system (Atlas Genetics Ltd.) runs clinical samples through a nucleic acid amplification test (NAAT)-based CT cartridge, delivering results in 30min. Prospective diagnostic accuracy study of the io® CT-assay in four UK Genito-Urinary Medicine (GUM)/RSH clinics on additional-to-routine self-collected vulvovaginal swabs. Samples were tested “fresh” within 10days of collection, or “frozen” at −80°C for later testing. Participant characteristics were collected to assess risk factors associated with CT infection. CT prevalence was 7.2% (51/709) overall. Sensitivity, specificity, positive and negative predictive values of the io® CT assay were, respectively, 96.1% (95% Confidence Interval (CI): 86.5–99.5), 97.7% (95%CI: 96.3–98.7), 76.6% (95%CI: 64.3–86.2) and 99.7% (95%CI: 98.9–100). The only risk factor associated with CT infection was being a sexual contact of an individual with CT. The io® CT-assay is a 30-min, fully automated, high-performing NAAT currently CE-marked for CT diagnosis in women, making it a highly promising diagnostic to enable specific treatment, initiation of partner notification and appropriately intensive health promotion at the point of care. •The io® CT assay's sensitivity is comparable to that of laboratory-based assays commonly used for Chlamydia detection.•The specificity as shown is this study is at the lower end of the range reported for laboratory-based assays.•The resulting positive predictive value, in this population, indicates that a targeted testing approach may be optimal. Until now, there have been no ≤30-min point-of-care test (POCT) nucleic acid amplification tests (NAATs) on the market for detecting Chlamydia trachomatis (CT), despite cost-effectiveness analyses demonstrating they may improve Genito-Urinary Medicine (GUM)/Reproductive and Sexual Health (RSH) clinical care pathway efficiencies and patient outcomes. Our evaluation of the 30-min Atlas Genetics io® CT NAAT POCT, on vaginal swabs from women attending four GUM/RSH clinics in England, shows that the test's sensitivity (accurately detecting CT-positive infections) is similar to that of laboratory-based NAATs, and its specificity (accurately detecting CT-negative infections) is at the lower end of the laboratory-based NAAT range.